scholarly journals THE RELATIONSHIP OF THE "SPHERE CHROMATOPHILE" TO THE FATE OF DISPLACED HISTONES FOLLOWING HISTONE TRANSITION IN RAT SPERMIOGENESIS

1966 ◽  
Vol 31 (2) ◽  
pp. 257-278 ◽  
Author(s):  
Jack C. Vaughn
Keyword(s):  
Basic Protein ◽  
Close Association ◽  
Protein Component ◽  
Spermatogenic Cells ◽  
Albino Rat ◽  
Spermatid Nucleus ◽  
Histone Synthesis ◽  
Different Origins ◽  
Relationship Of ◽  
The Relationship

Cytochemical, radioautographic, and microspectrophotometric studies bearing on the relationship of histone transition to the origin and development of the protein and RNA components of the "sphère chromatophile" in the developing spermatogenic cells of the albino rat are presented. These studies show that the sphère chromatophile has many features in common with somatic nuclei: it contains histonelike basic proteins rich in lysine, with lesser amounts of arginine. No evidence is found for the presence of a protamine in this granule. The sphère chromatophile is rich in RNA, but contains no DNA. The failure of a positive reaction with basic protein stains, unless the RNA is first removed, indicates either a chemical bonding or a very close association between the RNA and basic protein. The basic protein and RNA components of the sphère chromatophile appear to have different origins in the cell. A sequence of stages in the development of the lysine-rich basic protein component of this structure commences with the appearance of tiny grains in those spermatid nuclei which are beginning to replace lysine-rich histones with arginine-rich histones. Subsequently, similar-staining cytoplasmic grains appear, which coalesce to form the sphère chromatophile in the cytoplasm. Labeling studies show that the basic protein component is synthesized at about the time of the last premeiotic DNA (and histone) synthesis. The results of the microspectrophotometric measurements support the idea that the basic protein lost from the spermatid nucleus is the source of the basic protein in the sphère chromatophile.

scholarly journals The Relationship of Megazoobenthos Association with Seagrass Ecosystem Conditions in Ujung Genteng Waters, Sukabumi

2020 ◽  
pp. 1-10
Author(s):  
Gilang Primanagita Rachman ◽  
Indah Riyantini ◽  
Zahidah Hasan ◽  
Herman Hamdani
Keyword(s):  
Diversity Index ◽  
Close Association ◽  
Strong Relationship ◽  
Survey Method ◽  
Association Pattern ◽  
Seagrass Ecosystem ◽  
Relationship Of ◽  
The Relationship ◽  
Seagrass Density ◽  
Diadema Setosum

Seagrass beds in Ujung Genteng waters are one of the shallow marine ecosystems that have relatively high biodiversity. Seagrass ecosystem as one of the coastal ecosystems in these waters has a diversity of marine life that is associated with it. The purpose of this study was to establish the association pattern and the correlation of mega zoobenthos to seagrass ecosystem conditions. The method used was a survey method by conducting a survey direct observation of the stations that have been determined.  Three seagrass species were identified, namely: Thallasia hemprichii, Cymodoceae rotundata and Enhalus acoroides. The highest density of seagrass was found in station 2 with the type of seagrass Thallasia hemprichii as much as 207 ind/m2. Fifteen mega zoobenthos species were identified representing 3 phyla. Species Mega zoobenthos which is most commonly found in Ujung Genteng waters is Ophiothrix fragilis, Ophiocoma erinaceus, and Diadema setosum. The mega zoobenthos Diversity Index at the observation station is included in the medium category that is 2.33-2.66 and the evenness index is 0.63-0.84. Correlation of seagrass density with mega zoobenthos obtained by 0.92 shows that there is a very strong relationship between seagrass density with mega zoobenthos. The result shows that there are 4 patterns of close association and 2 patterns of very close association. Ophiocoma erinaceus of the ophiuroidea class has a pattern of very close positive associations with seagrass Cymodoceae rotundata and Dendrodoris sp of the order nudibranchia has a pattern of very close negative associations with seagrass Cymodoceae rotundata.

Studies on Graminicolous Species of Phyllachora Fckl. III.. The relationship of certain Scolecospores to species of Phyllachora

1963 ◽  
Vol 11 (2) ◽  
pp. 141 ◽  
Author(s):  
DG Parbery ◽  
RFN Langdon
Keyword(s):  
Close Association ◽  
Relationship Of ◽  
The Relationship ◽  
Test Plants ◽  
Mature Colony

The present study and a survey of literature showed that of the various spore types associated with species of Phyllachora, scolecospores typical of the form genus Leptostromella were most common. Examination has shown that certain spore types claimed as imperfect states of Phyllachora species are actually spores of hyperparasites. Evidence that the scolecospores belong to the Phyllachora species with which they are associated has been gathered. Studies on the development of P. parilis showed that the scolecospores associated with the perithecia of this species were genetically related to it. Attempts to germinate the scolecospores associated with three species of Phyllachora were unsuccessful. Similarly, when scolecospores 'were used as inoculum, test plants did not become infected. When ascosporic inoculum were used, however, infection occurred. Only one type of mycelium was found in each infection court, and pycnidia and perithecia developed from this in close association. Consequently, although the scolecosporous pycnidia developed prior to the perithecia, both types of fructification occurred in individual Phyllachora colonies. Within each mature colony the tissues of the pycnidia, perithecia, and clypeus became fused and were indistinguishable from one another. The development of the pycnidium and scolecospores is described, and it is shown that a different species of Leptostromella is associated with each different Phyllachora species. The Leptostromella species can be distinguished especially by the morphology of their sporophores. When it was shown that the morphology of the Leptostromella associated with each Phyllachora species was distinctive and constant, it was possible to assess the frequency and distribution of these associations. With some species of Phyllachora the association occurred in all specimens, while in others it was not as frequent. Always, however, the distribution of the association was as widespread as the species of Phyllachora concerned. It was noted that hyperparasites were able to parasitize the Leptostromella states as readily as the ascal states of various species of Phyllachora. The function of the scolecospores is not known, but it is suggested that they may be spermatia.

scholarly journals Investigation of the red algal parasites Rhodophyllis parasitica sp. nov. and Pterocladiophila hemisphaerica from New Zealand

2021 ◽  
Author(s):  
◽  
Maren Preuss
Keyword(s):  
Phylogenetic Analysis ◽  
New Zealand ◽  
Parasite Species ◽  
Nuclear Dna ◽  
Morphological Characteristics ◽  
Close Relationship ◽  
Red Algal ◽  
Different Origins ◽  
Relationship Of ◽  
The Relationship

<p>Red algal parasites are common within red algae and most parasites are closely related to their host. Red algal parasites can switch hosts and their development is unique. Red algal parasites are poorly known in New Zealand. There are only four parasites described in New Zealand and those are based on morphological characteristics. This thesis focuses on the two red algal parasites Rhodophyllis parasitica sp. nov. and Pterocladiophila hemisphaerica from New Zealand. First, development and phylogeny and distribution of an undescribed red algal parasite growing on Rhodophyllis membranacea was investigated. Microscopy, molecular markers (ITS2, cox1, cox2-3 spacer) and phylogenetic analysis, and herbarium sampling were used to address these questions. The parasite, described as Rhodophyllis parasitica sp. nov. shows a close relationship of all genomes to Rhodophyllis membranacea, which suggests that the parasite evolved from its hosts. The parasite is widely distributed throughout New Zealand. The second parasite, Pterocladiophila hemisphaerica was grouped taxonomically, based on morphology, in the order Gracilariales and parasitizes Pterocladia lucida in the order Gelidiales. Molecular marker were used to reveal the relationship of Pterocladiophila hemisphaerica to its host: if the parasite is grouped in the Gracilariales or the Gelidiales; if host switches might have occurred; and if atp8 is present in the parasite. Nuclear DNA (SSU rRNA, LSU rRNA), mitochondrial (cox1) and plastid regions (rbcL-rbcS spacer) from the parasite were sequenced and phylogenetic analysis performed. New primer were designed to amplify atp8 and genetic analysis performed. Pterocladiophila hemisphaerica evolved in the Florideophytes but neither in the Gracilariales or Gelidiales and the parasite possibly switched hosts at least two times, which was shown by three different origins of chloroplast, mitochondria and nuclear DNA. Atp8 in the parasite is present but probably a pseudogene. Rhodophyllis parasitica sp. nov. is the first described red algal parasite species in New Zealand in 55 years and Pterocladiophila hemisphaerica is the first parasite with organelles and nuclei with different histories of origin.</p>

Some Cytological Features of Epididymal Cells in the Rat

1958 ◽  
Vol s3-99 (47) ◽  
pp. 295-314
Author(s):  
B. L. REID
Keyword(s):  
Golgi Apparatus ◽  
Living Cell ◽  
Phase Contrast ◽  
Close Association ◽  
Fixed Material ◽  
Close Study ◽  
Cytological Features ◽  
Living Material ◽  
Relationship Of ◽  
The Relationship

Living material was photographed by phase-contrast miocroscopy. Fixed material was stained for mitochondria or post-osmicated. The findings show a close conformity between the pictures in living and fixed cells, except that the so-called Golgi apparatus, whilst very apparent in some zones by both techniques, in other zones is well represented after osmication but not in the living cell. Reasons for this are proposed. Studies by earlier workers on the mitochondrial pattern are confirmed. There is an increased density and decreased length of rods down the length of the epididymalduct. The relationship of the chondriome to the osmiophil material varies in the different zones; in some, close association with permeation is found, while in others the separation is complete. General observations upon living epididymal cells are recorded. These include the effects of different suspending media and the changes undergone by the cells after their isolation. A close study has been made of the free (stereociliated) border of the cells.

Depletion and refilling of intracellular Ca2+ stores induce oscillations of Ca2+ current

1993 ◽  
Vol 264 (4) ◽  
pp. H1319-H1322 ◽  
Author(s):  
L. Vaca ◽  
D. L. Kunze
Keyword(s):  
Patch Clamp ◽  
Vascular Endothelium ◽  
Close Association ◽  
Specific Inhibitor ◽  
Intracellular Store ◽  
Tert Butyl ◽  
Relationship Of ◽  
The Relationship

An agonist-induced Ca2+ influx pathway in vascular endothelium and other nonexcitable cells is closely aligned with the depletion of microsomal Ca2+ stores. The mechanism by which this occurs is unknown. In these studies 2',5',-di(tert-butyl-1,4-benzohydroquinone, a specific inhibitor of the microsomal Ca(2+)-adenosinetriphosphatase, and patch-clamp recordings were used to evaluate the relationship of inward Ca2+ current to the depletion of intracellular Ca2+ stores. The results demonstrate that depletion and refilling of Ca2+ stores control the amplitude of an electrogenic influx pathway in vascular endothelium. Prominent fluctuations in Ca2+ current occur when there is an imbalance between depletion and refilling of the stores. Furthermore, the studies suggest that the Ca2+ influx pathway is spatially in close association with the intracellular store.

Spatial orientation of the facial nerve in relation to parotid tumours

2006 ◽  
Vol 120 (5) ◽  
pp. 371-374 ◽  
Author(s):  
D W Aird ◽  
P Puttasiddaiah ◽  
S Berry ◽  
C Spyridakou ◽  
M Kumar
Keyword(s):  
Facial Nerve ◽  
Close Association ◽  
District General Hospital ◽  
The Body ◽  
Pleomorphic Adenomas ◽  
Lower Division ◽  
Parotid Tumours ◽  
A Prospective Study ◽  
Relationship Of ◽  
The Relationship

Objective: The aim of this study was to identify the distribution of parotid tumours within the gland in relation to the facial nerve branches. Documentation revealing such a relationship has not been reported previously.Method: A prospective study involving 111 patients was carried out over a period of 18 years in a specialist otolaryngology unit within a district general hospital. The relationship of the facial nerve to the tumour was graded into six types. The grading system was then employed to categorize each case.Results: More than two-thirds of the tumours were pleomorphic adenomas. The majority of these were located in the body and not in the tail of the parotid gland. In 50 per cent of these cases, the tumour was in close association with the two major divisions of the facial nerve. In the case of Warthin's tumours, 47 per cent were located in the tail, below the lower division of the facial nerve.

The Relationship of Physics to Aeronautical Research

1926 ◽  
Vol 30 (191) ◽  
pp. 668-675
Author(s):  
H. E. Wimperis
Keyword(s):  
Close Association ◽  
Linear Motion ◽  
Applied Physics ◽  
Intake Pressure ◽  
Definition Of ◽  
Relationship Of ◽  
The Relationship

Aeronautics is a youthful study—a mere Cinderella of the Sciences, distinguished from her sisters by her tender years, by her guileless and impetuous disregard of the pinch of the financial shoe, and by her beauty.That it is Applied Physics is to me the most inspiring definition of engineering; and if this be true for engineering in general, as I think it is, especially true is it of aeronautics. To illustrate the close association of these new studies with the work of physicists, I shall select a few of the more striking results of recent research.Aviation is now entering upon a new and intensely interesting phase—one which will call for every scientific resource at our command. The materials of -construction are changing : wood is giving place to metal. The engine proves ito have most unexpected possibilities ahead of it through the increase of intake pressure; whilst the very lifting structure itself promises to change, for some purposes at least, from linear motion to rotary.

scholarly journals Entangled Legalities Beyond the State

2021 ◽  
Keyword(s):  
Financial Markets ◽  
International Law ◽  
Political Theory ◽  
Coherent System ◽  
Theoretical Approaches ◽  
Wide Range ◽  
Corporate Social ◽  
Different Origins ◽  
Relationship Of ◽  
The Relationship

Law is usually understood as an orderly, coherent system, but this volume shows that it is often better understood as an entangled web. Bringing together eminent contributors from law, political science, sociology, anthropology, history and political theory, it also suggests that entanglement has been characteristic of law for much of its history. The book shifts the focus to the ways in which actors create connections and distance between different legalities in domestic, transnational and international law. It examines a wide range of issue areas, from the relationship of state and indigenous orders to the regulation of global financial markets, from corporate social responsibility to struggles over human rights. The book uses these empirical insights to inform new theoretical approaches to law, and by placing the entanglements between norms from different origins at the centre of the study of law, it opens up new avenues for future legal research. This title is also available as Open Access.

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