Bangia

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Zhen Weng - One of the best experts on this subject based on the ideXlab platform.

Wendy A. Nelson - One of the best experts on this subject based on the ideXlab platform.

  • History of the typification of conserved and rejected names, including an account of the typification of Bangia Lyngb. (Bangiaceae, Rhodophyta)
    TAXON, 2008
    Co-Authors: Paul C. Silva, Wendy A. Nelson
    Abstract:

    The provision for conserved and rejected generic names entered the botanical code of nomenclature 25 years before the type method was adopted. All conserved and rejected generic names approved by an international botanical congress prior to 1954 were applied in accordance with circumscriptions. Bringing the lists of names into accordance with the type method resulted in the finding that many names had been unnecessarily conserved, Bangia Lyngb. among them. Silva's choice of Conferva fuscopurpurea Dillwyn as generitype must be rejected in favor of Pfeiffer's previous choice of C. atropurpurea Mert. ex Roth. Bangiadulcis W.A. Nelson, based on C. atropurpurea, is thus rendered a superfluous name for Bangia Lyngb. The latter name when properly typified applies to a genus that currently comprises a single freshwater species. Generic limits remain to be established among the phylogenetically diverse marine populations currently assigned to Bangia.

  • Bangiadulcis gen. nov.: a new genus for freshwater filamentous Bangiales (Rhodophyta)
    TAXON, 2007
    Co-Authors: Wendy A. Nelson
    Abstract:

    A new monotypic genus, Bangiadulcis (Bangiales, Rhodophyta) is described to accommodate the freshwater, filamentous species found in Europe, North America, and Japan, previously known as Bangia atropurpurea (Roth) C. Agardh. Bangiadulcis can be distinguished from other members of the Bangiales on the basis of cytological, reproductive, and ecological characters. Phylogenetic analyses of molecular sequence data have provided strong support for this distinct lineage.

  • Unusual Rhizoidal Development in Bangia (Bangiales, Rhodophyta) -Another Form of Vegetative Reproduction?
    ALGAE, 2007
    Co-Authors: Christian Boedeker, Tracy J. Farr, Wendy A. Nelson
    Abstract:

    The gametophytic filaments of two genetically distinct taxa of Bangia from New Zealand showed unusual rhizoidal development in comparative culture experiments. In the past Bangia has been reported to possess simple, colourless rhizoids that extend from the basal cells of the unbranched filaments, whereas in this study the rhizoids observed became pigmented and multicellular. A reversal of growth direction occurred and filamentous extensions developed from the rhizoids under some culture conditions. These extensions were either prostrate or resembled new gametophytic filaments. This is the first report for filamentous members of the Bangiales of the development of such stolon-like rhizoids, apparently serving as a form of vegetative reproduction. ﾖ⨀ጊ츀Ѐ㔹〻Ԁ䭃䑎䷙᜕ಢ5㤰⸵㬅K䍄乍

  • Phylogeny of the Bangia flora of New Zealand suggests a southern origin for Porphyra and Bangia (Bangiales, Rhodophyta)
    Molecular Phylogenetics and Evolution, 2004
    Co-Authors: Judy E. Broom, Tracy J. Farr, Wendy A. Nelson
    Abstract:

    Analysis of nuclear small subunit ribosomal RNA gene (18S rDNA) sequence data from 123 samples of the red algal genus Bangia from mainland New Zealand has revealed diversity exceeding that reported for the genus from any other region in the world. Our study resolves two New Zealand Bangia taxa basal to the order Bangiales, and five clades of Bangia, four of which include New Zealand members. The basal taxa are separated from each other by 139 bp and differ from all other Bangia taxa in the New Zealand region by 103-163 bp over approximately 1750 bp 18S rDNA sequence data. Our results reveal a Bangia flora of previously unsuspected richness, and show that the simple morphology of these organisms obscures significant levels of genetic diversity. The presence of high diversity and retention of basal taxa in New Zealand Bangia raises the prospect that the southern hemisphere, and particularly eastern Gondwana, is not only a centre of diversity, but a centre of origin for the modern Bangiales.

  • CONFUSING CONVERGENT MORPHOLOGIES: DIVERSITY AND DIFFICULTIES IN NEW ZEALAND ERYTHROPELTIDALES AND BangiaLES
    Journal of Phycology, 2000
    Co-Authors: Wendy A. Nelson, J. E. Broom, Tracy J. Farr
    Abstract:

    An examination of New Zealand species of Porphyra and Bangia has led to the discovery of unexpectedly high diversity. In excess of 30 species of Porphyra and 5 species of Bangia can be distinguished, based on 18S rDNA sequence data. It is possible to develop a workable taxonomic framework to distinguish species of Porphyra found within this geographic region using a range of characters (morphological, anatomical, biochemical, physiological, life history characteristics). However, the taxonomic distinctions do not necessarily reflect phylogenetic relationships revealed by sequence analyses: convergence in character states is obscuring relationships. In the course of our work we have discovered that four species, originally described on the basis of traditional morphological and anatomical characters as Porphyra or Bangia, are more closely related to members of the order Erythropeltidales than to the Bangiales. These results are challenging us to consider new ways of describing and defining these organisms. We are finding convergence in character states, not only within Porphyra sens. lat. But spanning both the Bangiales and Erythropeltidales, which confounds both taxonomic distinctions and also phylogenetic hypotheses based on morphology and anatomy. This confusion could be countered effectively by the inclusion of molecular sequence data based on vouchered or type material in descriptions of taxa in the orders Bangiales and Erythropeltidales. This would allow conclusive identification of collected material by appropriate molecular tests, which are quicker and more direct identification tools than, for example, using characters drawn from the growth of these organisms under controlled culture conditions.

Mohammad Nurul Huda - One of the best experts on this subject based on the ideXlab platform.

  • MLN-based Bangla ASR using context sensitive triphone HMM
    International Journal of Speech Technology, 2011
    Co-Authors: Foyzul Hassan, Mohammed Rokibul Alam Kotwal, Ghulam Muhammad, Mohammad Nurul Huda
    Abstract:

    Building a continuous speech recognizer for the Bangla (widely used as Bengali) language is a challenging task due to the unique inherent features of the language like long and short vowels and many instances of allophones. Stress and accent vary in spoken Bangla language from region to region. But in formal read Bangla speech, stress and accents are ignored. There are three approaches to continuous speech recognition (CSR) based on the sub-word unit viz. word, phoneme and syllable. Pronunciation of words and sentences are strictly governed by set of linguistic rules. Many attempts have been made to build continuous speech recognizers for Bangla for small and restricted tasks. However, medium and large vocabulary CSR for Bangla is relatively new and not explored. In this paper, the authors have attempted for building automatic speech recognition (ASR) method based on context sensitive triphone acoustic models. The method comprises three stages, where the first stage extracts phoneme probabilities from acoustic features using a multilayer neural network (MLN), the second stage designs triphone models to catch context of both sides and the final stage generates word strings based on triphone hidden Markov models (HMMs). The objective of this research is to build a medium vocabulary triphone based continuous speech recognizer for Bangla language. In this experimentation using Bangla speech corpus prepared by us, the recognizer provides higher word accuracy as well as word correct rate for trained and tested sentences with fewer mixture components in HMMs.

  • generation of attributes for bangla words for universal networking language unl
    International Journal of Advanced Computer Science and Applications, 2011
    Co-Authors: Muhammad F Mridha, Manoj Banik, Mohammad Nurul Huda
    Abstract:

    The usage of native language through Internet is highly demanding now a day due to rapidly increase of Internet based application in daily needs. It is important to read all information in Bangla from the internet. Universal Networking Language (UNL) addressed this issue in most of languages. It helps to overcome the language barrier among people of different nations to solve problems emerging from current globalization trends and geopolitical interdependence. In this paper we propose a work that aims to contribute with morphological analysis of those Bangla words from which we obtain roots and Primary suffixes and developing of grammatical attributes for roots and Primary suffixes that can be used to prepare Bangla word dictionary and Enconversion/Deconversion rules for Natural Language Processing(NLP).

  • structure of dictionary entries of bangla morphemes for morphological rule generation for universal networking language
    Computer Information Systems and Industrial Management Applications, 2010
    Co-Authors: Muhammad F Mridha, Mohammad Nurul Huda, Md Sadequr Rahman, Chowdhury Mofizur Rahman
    Abstract:

    Dictionary plays a crucial role in any machine translation (MT) system. The Universal Networking Language (UNL) is an artificial language developed for conveying linguistic expressions in order to represent websites information into a standard form. In order to integrate Bangla into this platform it is necessary to develop both a dictionary and a grammar. This paper focuses on the development of a Structure of Dictionary Entries and Analysis of Grammatical Attributes of Bangla words such as Bangla Roots, Krit Prottoy (primary suffix) and Kria Bivokti (verb suffix). The goal is to make possible Bangla sentence encoversion to UNL and vice-versa. The theoretical analysis of our model proves that the proposed work is successfully able to prepare Universal words for Bangla roots, Krit Prottoy and Kria Bivokti along with their grammatical attributes for UNL.

  • automatic speech recognition for bangla digits
    Annual Conference on Computers, 2009
    Co-Authors: Ghulam Muhammad, Yousef Ajami Alotaibi, Mohammad Nurul Huda
    Abstract:

    In this paper, we introduce a system for Bangla digit automatic speech recognition (ASR). Though Bangla is one of the largely spoken languages in the world, only a few works on Bangla ASR can be found in the literature, especially on Bangladeshi accented Bangla. In this work, the corpus is collected from natives in Bangladesh. Mel-frequency cepstral coefficients (MFCCs) based features and hidden Markov model (HMM) based classifiers are used for recognition. Experimental results show comparatively high recognition performance (more than 95%) for first six digits (0 – 5) and low performance (less than 90%) for the next four digits (6 – 9). We notice two confused pairs of digits: one with (6) and (9), and the other with (7) and (8), in the experiments. We also find that different dialects in Bangladesh have a greater role on this confusion.

  • Automatic Speech Recognition for Bangia Digits
    2009
    Co-Authors: Ghulam Muhammad, Yousef Ajami Alotaibi, Mohammad Nurul Huda
    Abstract:

    In this paper, we introduce a systemfor Bangia digit automatic speech recognition (ASR). Though Bangia is one ofthe largely spoken languages in the world, only a few works on Bangia ASR can befound in the literature, especially on Bangladeshi accented Bangia. In this work, the corpus is collected from natives in Bangla­ desh. Mel-frequency cepstral coefficients (MFCCs) based features and hidden Markov model (HMM) based classifiers are used for recognition. Experimental re­ sults show comparatively high recognition performance (more than 95%) for first six digits (0 - 5) and low performance (less than 90%) for the next four digits(6 ­ 9). We notice tlVo confusedpairs ofdigits: one with 'c,' (6) and ';,' (9), and the other with ''/' (7) and 'y' (8), in the experiments. We alsofind that different dialects in Bangladesh have a greater role on this confusion.

Min Cao - One of the best experts on this subject based on the ideXlab platform.

Kirsten M. Müller - One of the best experts on this subject based on the ideXlab platform.

  • Distribution, seasonality and putative origin of the non-native red alga Bangia atropurpurea (Bangiales, Rhodophyta) in the Laurentian Great Lakes
    Journal of Great Lakes Research, 2014
    Co-Authors: Troina B. Shea, Robert G. Sheath, Aline Chhun, Morgan L. Vis, Wayne B. Chiasson, Kirsten M. Müller
    Abstract:

    Abstract Bangia atropurpurea was first observed in Lake Erie in 1964 and subsequently spread to the lower Laurentian Great Lakes by the mid to late 1970s. The present study was initiated to examine the recent distribution of B. atropurpurea in the Great Lakes, the seasonal variation of the alga and the putative origin of this species based on DNA sequence analysis. From surveys in 1995 and 2002, this species has clearly spread, with newly identified populations observed in Lakes Huron, Michigan, Georgian Bay and the St. Lawrence River. Morphological analyses showed that Great Lakes populations from individual lakes or neighboring populations did not group together in cluster analyses. Correlation analysis, however, revealed significant relationships between the presence or absence of Bangia among the studied sites with pH and specific conductance as those locations that had stable populations had a mean pH and conductance of 8.2 and 353 μS·cm − 1 respectively. Seasonal variation in morphology of a population from Burlington, Ontario (Lake Ontario, Canada) was examined monthly for one year. Maximum filament length occurred in April, with the greatest diameter and archaeospore production observed in May. Significant correlations were also noted for many morphological characteristics with water temperature, population height on the shoreline relative to the waterline and total phosphorus. Collections of B. atropurpurea analyzed from the Great Lakes were observed to be identical in sequence to collections of European freshwater Bangia in the cox2–3 gene spacer, the nuclear internal transcribed spacers (ITS 1 and 2) and the 5.8S rRNA gene (between the small and large subunits of the rRNA gene). These results suggest a recent European origin; however, further global collections of B. atropurpurea and microsatellite analyses are necessary to confirm this hypothesis.

  • Phylogenetic position and ISSR-estimated intraspecific genetic variation of Bangia maxima (Bangiales, Rhodophyta)
    Phycologia, 2008
    Co-Authors: Michael D. Lynch, Robert G. Sheath, Kirsten M. Müller
    Abstract:

    Abstract The red alga Bangia maxima, in addition to its large size (up to 35 cm long × 6 mm in diameter), was found in this study to be distinguishable from other species of Bangia by the character of mature filament apices containing elongate, separated vegetative cells. The phylogenetic position of B. maxima was resolved using both the rbcL and nuclear small subunit rRNA (nSSU rRNA) gene sequences and the genetic variation within a population was studied using an inter-simple sequence repeat (ISSR) polymerase chain reaction (PCR)-based DNA fingerprint analysis. In phylogenetic analyses of the plastid rbcL gene region and nSSU rRNA, B. maxima grouped with local populations of concurrently collected B. vermicularis and B. fuscopurpurea as well as other collections of B. fuscopurpurea from California in a clade of predominantly eastern Pacific isolates. Banding patterns from 13 male filaments from seven littoral boulders for five ISSR primers were used to develop both band presence or absence and distance ...

  • A molecular phylogenetic analysis of the Bangiales (Rhodophyta) and description of a new genus and species, PseudoBangia kaycoleia
    Phycologia, 2005
    Co-Authors: Kirsten M. Müller, Jamie J. Cannone, Robert G. Sheath
    Abstract:

    Abstract A red alga collected from the Virgin Islands (VIS7) superficially resembles Bangia but was found to have characteristics distinct from known members of the Bangiales. This alga is distinguished by having multiple chloroplasts per cell; as many as nine were observed in one cell. Each chloroplast has a single pyrenoid. In the 18S ribosomal RNA (rRNA) gene sequence analyses, this entity is well supported as being a member of the Bangiales. The relationship between this collection and other Bangialean collections is unclear; it appears to be associated with a clade of B. fuscopurpurea from the Atlantic and the Pacific, but this relationship is only moderately supported by neighbour-joining bootstrap. The sequence divergence between the VIS7 collection and other collections of Bangia and Porphyra ranged from 6.9% to 12.6%. This amount of divergence is greater than that observed within many of the clades in the 18S rRNA gene sequence analyses and is slightly less than that noted between the Bangiales a...

  • Systematics of Bangia (Bangiales, Rhodophyta) in North America. II. Biogeographical trends in karyology: chromosome numbers and linkage with gene sequence phylogenetic trees
    Phycologia, 2003
    Co-Authors: Kirsten M. Müller, Kathleen M. Cole, Robert G. Sheath
    Abstract:

    An extensive karyological analysis was carried out on marine and freshwater Bangia from North America (70°N to c. 23°N), including 40 collections from the Pacific, 39 from the Atlantic, 8 from the Laurentian Great Lakes and also 2 freshwater collections from Europe for comparison with the Great Lakes material. Chromosome numbers were determined and linked to gene trees derived from DNA sequence analyses of the chloroplast rbcL and nuclear small-subunit (SSU) rRNA genes. For the first time in one continent, five different chromosomal types were observed among marine populations, viz. monosporic plants with three (n), tour (n) or six (2n) chromosomes and sexual plants with three (n)/six (2n) or four (n)/eight (2n) chromosomes. These types were also characterized with respect to seasonality and distribution. Freshwater Bangia filaments were all monosporic, with three chromosomes and a distinctive chromosome morphology: the third chromosome is very mach smaller than that in marine three-chromosome collections. Based on these observations and DNA sequence analyses in which freshwater collections of Bangia are positioned on a separate and well-supported branch, we propose resurrecting the name B. atropurpurea to represent this lineage. There also appear to be some distinct entities among the marine Bangia occurring along North American coastlines, judging by chromosome numbers and gene trees. For example, there is a transarctic group of monosporic three-chromosome plants that have identical sequences for vbcL and very similar nuclear SSI rRNA gene sequences. However, populations of Bangia along the mid to southern coasts of North America with the same chromosome number were not always found to cluster together in gene trees, suggesting a mixing of multiple species brought about possibly by vector-assisted transport. At this time, marine populations should continue to he recognized as B. fuscopurpurea until their complex relationships can be resolved.

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