scholarly journals Maintenance of genetic and morphological identity in two sibling Syrrhopodon species (Calymperaceae, Bryopsida) despite extensive introgression

2019 ◽  
Vol 57 (4) ◽  
pp. 395-403 ◽  
Author(s):  
Marta R. Pereira ◽  
Alice Ledent ◽  
Patrick Mardulyn ◽  
Charles E. Zartman ◽  
Alain Vanderpoorten
Keyword(s):  
Morphological Identity

Locality and Logophoricity

2019 ◽  
Author(s):  
Isabelle Charnavel
Keyword(s):  
Binding Theory ◽  
Long Distance ◽  
The Cross ◽  
Morphological Identity

Anaphors such as English herself, French elle-même, and Mandarin ziji are usually claimed to obey locality requirements stated by Condition A of Binding Theory. But we observe that in various languages, the same anaphors can be exempt from these locality requirements under certain conditions. The goal of this book is to describe and explain this widespread dual behavior of anaphors on the basis of French, English, Mandarin, Korean, and Icelandic. First, several strategies are proposed for distinguishing between the two possible behaviors of anaphors. Plain instances of anaphors require local and exhaustive binding, as well as sloppy readings in ellipsis. Exempt instances of anaphors, however, only require a logophorical interpretation, that is, to occur in phrases expressing the first-personal, mental perspective of their antecedent. Second, a new theory of exempt anaphora is proposed, which consists in deriving all properties distinguishing exempt from plain anaphors to one: the presence of a silent, syntactically represented logophoric operator introducing a local, perspectival binder for superficially exempt anaphors. This hypothesis parsimoniously reduces exempt to plain anaphors obeying Condition A, thus directly accounting for the cross-linguistically widespread morphological identity of plain and exempt anaphors. Under this proposal, the reason why exempt anaphors appear to escape locality requirements is that their binder is implicit, and their mandatory logophoric interpretation derives from the nature of this binder. Finally, several diagnostics are provided for testing the hypothesis that so-called long-distance anaphors can be analyzed just like exempt instances of anaphors.

Patch-clamp study of neurons and glial cells in isolated myenteric ganglia

2000 ◽  
Vol 278 (4) ◽  
pp. G644-G651 ◽  
Author(s):  
M. Hanani ◽  
M. Francke ◽  
W. Härtig ◽  
J. Grosche ◽  
A. Reichenbach ◽  
...  
Keyword(s):  
Patch Clamp ◽  
Glial Cells ◽  
Muscle Layer ◽  
Membrane Receptors ◽  
Delayed Rectifier ◽  
Longitudinal Muscle Layer ◽  
Inward Currents ◽  
Morphological Identity ◽  
Clamp Study ◽  
Myenteric Ganglia

Most of the physiological information on the enteric nervous system has been obtained from studies on preparations of the myenteric ganglia attached to the longitudinal muscle layer. This preparation has a number of disadvantages, e.g., the inability to make patch-clamp recordings and the occurrence of muscle movements. To overcome these limitations we used isolated myenteric ganglia from the guinea pig small intestine. In this preparation movement was eliminated because muscle was completely absent, gigaseals were obtained, and whole cell recordings were made from neurons and glial cells. The morphological identity of cells was verified by injecting a fluorescent dye by micropipette. Neurons displayed voltage-gated inactivating inward Na+ and Ca2+currents as well as delayed-rectifier K+ currents. Immunohistochemical staining confirmed that most neurons have Na+ channels. Neurons responded to GABA, indicating that membrane receptors were retained. Glial cells displayed hyperpolarization-induced K+ inward currents and depolarization-induced K+ outward currents. Glia showed large “passive” currents that were suppressed by octanol, consistent with coupling by gap junctions among these cells. These results demonstrate the advantages of isolated ganglia for studying myenteric neurons and glial cells.

scholarly journals GENETIC IDENTIFICATION OF AQUATIC INVERTEBRATES OF KAZAKHSTAN AS INDICATORS OF ORGANIC POLLUTANTS

2018 ◽  
pp. 139-148
Author(s):  
Alexandr Anatoljevich Volkov ◽  
Larisa Anatoljevna Kovaljova ◽  
Tatjana Timofeevna Troshina ◽  
Zhanara Omirbekovna Mazhibaeva ◽  
Dmitrij Valerjevich Pilin ◽  
...  
Keyword(s):  
Dna Barcoding ◽  
Phylogenetic Trees ◽  
Aquatic Invertebrates ◽  
Species Abundance ◽  
Ecological Status ◽  
Taxonomic Status ◽  
Organic Pollution ◽  
Water Bodies ◽  
Genetic Identification ◽  
Morphological Identity

The article deals with carrying out DNA barcoding of aquatic invertebrates of Kazakhstan to identify their taxonomic status as organic pollution indicators. 33 species of the Balkhash-Alakol basin and the Zhayik river were analyzed. 21 species correlate (95-100%) with previously published sequences of invertebrates with well-known classifications in the GenBank and BOLD databases. The taxonomic discrepancy in morphometric and genetic parameters in certain species has been revealed. The discrepancy may be caused by the morphological identity in chironomids at a larval stage. The phylogenetic trees of the investigated species within the families Chironomidae and Moinidae have been indicated. Chironomids are represented by ten clades of different types of genetic polymorphism of DNA gene. Genetic links of Moinidae are detected in four groups including a cryptic species from Lake Alakol. It has been stated that in distribution of cryptic taxons in Moina family factors of salinity and depth of the lake are important, as well as differences in depth. Molecular DNA-barcoding of invertebrates of Kazakhstan should be continued with covering a greater number of species and several replications, with qualified primary fixation of subjects of research and a sufficient number of samples. Authenticity of composition defining, species abundance, species characteristics of aquatic invertebrates from the water bodies of poorly explored arid regions is necessary for using them as indicators of the ecological status of water bodies.

scholarly journals STUDIES ON AN UNCOMPLICATED CORYZA OF THE DOMESTIC FOWL

1936 ◽  
Vol 64 (5) ◽  
pp. 749-758 ◽  
Author(s):  
John B. Nelson
Keyword(s):  
Microscopic Examination ◽  
Domestic Fowl ◽  
Living Cells ◽  
Fetal Membranes ◽  
Tissue Cultures ◽  
Morphological Identity

The coccobacilliform bodies of fowl coryza were successfully cultivated in the fetal membranes of fertile eggs. Microscopic examination indicated growth in approximately 50 per cent of 94 eggs inoculated on the 3rd to 4th day of incubation. Growth was generally inhibited, however, in eggs inoculated on the 10th day. One strain of the specific bodies was maintained through 11 successive passages in 4 day eggs. A more consistent growth of the coccobacilliform bodies was obtained in tissue cultures. One strain, originally isolated in November, 1935, has been carried through 100 successive subcultures at intervals of 1–3 days. The specific bodies fail to maintain their morphological identity for any length of time in this medium. It is noted that growth of the coccobacilliform bodies in fertile eggs and in tissue cultures is not dependent on the presence of living cells.

Organelle morphogenesis by active membrane remodeling

Soft Matter ◽  
2015 ◽  
Vol 11 (12) ◽  
pp. 2387-2393 ◽  
Author(s):  
N. Ramakrishnan ◽  
John H. Ipsen ◽  
Madan Rao ◽  
P. B. Sunil Kumar
Keyword(s):  
Membrane Trafficking ◽  
Eukaryotic Cells ◽  
Membrane Remodeling ◽  
Active Membrane ◽  
Internal Membrane ◽  
Membrane Bound ◽  
Morphological Identity ◽  
Non Equilibrium

Eukaryotic cells are characterized by having well defined internal membrane bound organelles with distinct morphological identity. We explore the issue of morphogenesis in the context of organelles subject to intense membrane trafficking and show that non-equilibrium driven processes are at the heart of organelle morphogenesis.

Sequence heterogeneity of the small subunit ribosomal RNA genes among Blastocystis isolates

Parasitology ◽  
2003 ◽  
Vol 126 (1) ◽  
pp. 1-9 ◽  
Author(s):  
N. ARISUE ◽  
T. HASHIMOTO ◽  
H. YOSHIKAWA
Keyword(s):  
Ribosomal Rna ◽  
Phylogenetic Reconstruction ◽  
Small Subunit ◽  
Higher Order ◽  
Variable Regions ◽  
Small Subunit Ribosomal Rna ◽  
Statistical Confidence ◽  
Sequence Patterns ◽  
Genes Encoding ◽  
Morphological Identity

Genes encoding small subunit ribosomal RNA (SSUrRNA) of 16 Blastocystis isolates from humans and other animals were amplified by the polymerase chain reaction, and the corresponding fragments were cloned and sequenced. Alignment of these sequences with the previously reported ones indicated the presence of 7 different sequence patterns in the highly variable regions of the small subunit ribosomal RNA. Phylogenetic reconstruction analysis using Proteromonas lacertae as the outgroup clearly demonstrated that the 7 groups with the different sequence patterns are separated to form independent clades, 5 of which consisted of the Blastocystis isolates from both humans (B. hominis) and other animals. The presence of 3 higher order clades was also clearly supported in the phylogenetic tree. However, a relationship among the 4 groups including these 3 higher order clades was not settled with statistical confidence. The remarkable heterogeneity of small subunit ribosomal RNAs among different Blastocystis isolates found in this study confirmed, with sequence-based evidence, that these organisms are genetically highly divergent in spite of their morphological identity. The highly variable small subunit ribosomal RNA regions among the distinct groups will provide useful information for the development of group-specific diagnostic primers.

scholarly journals The Morphology of the Traditional Fallujah Market between 1870 and 1958

2020 ◽  
Author(s):  
Hasan Al janabia ◽  
Alaa Al Anib
Keyword(s):  
Ottoman Empire ◽  
Transport Infrastructure ◽  
Urban Identity ◽  
Heating And Cooling ◽  
Architectural Styles ◽  
The People ◽  
Traditional Market ◽  
Morphological Identity ◽  
The City

This study analyses the regional and autonomous components of the emergence and development of the traditional market of the city of Fallujah, initially a simple and modest commercial centre that evolved into a major urban hub by the end of the Ottoman empire. In particular, the article considers the use of traditional Arab architectural styles where, owing to the lack of modern methods of lighting, heating and cooling, architects sought to utilise the sun, moon and air currents. The role of the city as a vital nexus in the region;s transport infrastructure is also considered, as these transport links served as a catalytic external force which drove the expansion of the Fallujah marketplace and profoundly im[acted its urban identity. By studying the morphological reality of the market of the city of Fallujah in terms of origin and internal composition as well as urban fabric, this study hopes to offer new insights into the morphological identity of the city. It was necessary to follow and adopt a methodology for research through the descriptive-analytical method based on the collection of information, both from the sources that addressed the city and field study through direct observation and question the people of the city, especially the centenarians and officials in the municipality and a questionnaire. Keywords: Architectural styles, Khans, Fallujah market, commercial establish- ments, morphology

Complexity in Polyploid Species Origin and Establishment: Arctostaphylos mewukka (Ericaceae)

2021 ◽  
Author(s):  
Steven Serkanic ◽  
V. Thomas Parker ◽  
Kristina Schierenbeck
Keyword(s):  
Sierra Nevada ◽  
Woody Plant ◽  
Genome Duplication ◽  
Sequence Data ◽  
Western Slope ◽  
Target Species ◽  
Molecular Sequence Data ◽  
Interspecific Gene Flow ◽  
Molecular Sequence ◽  
Morphological Identity

Lineage recombination is an important source of genetic and morphological variation in species-rich groups of plants. Tetraploids that are intermediate in morphology and ecology with respect to sympatric diploids are regularly hypothesized to be the products of hybridization. Arctostaphylos mewukka is one such intermediate tetraploid long regarded as the result of hybridization and genome duplication among divergent and geographically overlapping diploids widely distributed across the western slope of the Sierra Nevada. Here we set out to test this hypothesis leveraging the notion that allopolyploids arise repetitively and may show signs of reciprocal organellar exchange among species between maternal and paternal progenitors. We compared nuclear ribosomal and plastid sequence data acquired from samples within and outside this target species complex. Molecular sequence data show striking patterns indicative of widespread reticulation and chloroplast captureevents across the genus Arctostaphylos. Results support the notion that outcrossing, long-lived woody plant species such as members of the genus Arctostaphylos can retain a secured morphological identity despite ongoing influence of interspecific gene flow that would otherwise render speciesboundaries vulnerable to dissolution.

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