Ultrastructure of the basal body apparatus in epidermal cells of a sponge larva (Aplysilla SP: Demospongiae)

1992 ◽  
Vol 50 (1) ◽  
pp. 928-929
Author(s):  
R.L. Pinto ◽  
R.M. Woollacott
Keyword(s):  
Sodium Bicarbonate ◽  
Epoxy Resin ◽  
Basal Body ◽  
Phosphate Buffer ◽  
Similar Data ◽  
Basal Apparatus ◽  
Striated Rootlet ◽  
The Common ◽  
Basal Foot ◽  
Sexually Mature

The basal body and its associated rootlet are the organelles responsible for anchoring the flagellum or cilium in the cytoplasm. Structurally, the common denominators of the basal apparatus are the basal body, a basal foot from which microtubules or microfilaments emanate, and a striated rootlet. A study of the basal apparatus from cells of the epidermis of a sponge larva was initiated to provide a comparison with similar data on adult sponges.Sexually mature colonies of Aplysillasp were collected from Keehi Lagoon Marina, Honolulu, Hawaii. Larvae were fixed in 2.5% glutaraldehyde and 0.14 M NaCl in 0.2 M Millonig’s phosphate buffer (pH 7.4). Specimens were postfixed in 1% OsO4 in 1.25% sodium bicarbonate (pH 7.2) and embedded in epoxy resin. The larva ofAplysilla sp was previously described (as Dendrilla cactus) based on live observations and SEM by Woollacott and Hadfield.

scholarly journals THE THREE-DIMENSIONAL STRUCTURE OF THE BASAL BODY FROM THE RHESUS MONKEY OVIDUCT

1972 ◽  
Vol 54 (2) ◽  
pp. 246-265 ◽  
Author(s):  
Richard G. W. Anderson
Keyword(s):  
Basal Body ◽  
Three Dimensional ◽  
Longitudinal Axis ◽  
Scale Model ◽  
Dimensional Structure ◽  
Transverse Axis ◽  
Longitudinal Edge ◽  
Striated Rootlet ◽  
Basal Foot ◽  
Base View

The structure of the oviduct basal body has been reconstructed from serial, oblique, and tangential sections This composite information has been used to construct a three-dimensional scale model of the organelle The walls are composed of nine equally spaced sets of three tubules, which run from base to apex pitched to the left at a 10°–15° angle to the longitudinal axis. The transverse axis of each triplet set at its basal end intersects a tangent to the lumenal circumference of the basal body at a 40° angle (triplet angle). As the triplet set transverses from base to apex, it twists toward the lumen on the longitudinal axis of the inner A tubule; therefore, the triplet angle is 10° at the basal body-cilium junction. Strands of fibrous material extend from the basal end of each triplet to form a striated rootlet. A pyramidal basal foot projects at right angles from the midregion of the basal body. In the apex, a 175 mµ long trapezoidal sheet is attached to each triplet set. The smaller of the two parallel sides is attached to all three tubules while the longitudinal edge (one of the equidistant anti-parallel sides) is attached to the C tubule. The sheet faces counterclockwise (apex to base view) and gradually unfolds from base to apex; the outside corner merges with the cell membrane.

Developments in the Field of Rapid Prototype Production

2008 ◽  
Vol 589 ◽  
pp. 421-425 ◽  
Author(s):  
Norbert Krisztián Kovács ◽  
József Gábor Kovács
Keyword(s):  
Mechanical Strength ◽  
Porous Structure ◽  
Epoxy Resin ◽  
Rapid Prototype ◽  
Post Treatment ◽  
3D Printer ◽  
Infiltration Depth ◽  
3D Printed ◽  
The Common ◽  
Polymer Engineering

Characteristics of 3D printed specimens are porous structure and low mechanical strength. Due to porous structure post treatment is possible, and in most cases infiltration with an epoxy resin, wax or cyanoacrylate material takes place. As a result of post treatment, the mechanical strength can be increased by 100%, although this is strongly influenced by the infiltration depth that depends on the porous structure and the resin viscosity. In the framework of the common research of the Department of Polymer Engineering, BME and Varinex Zrt. the applicability of a 3D printer is examined in the field of direct tool making. As the first step, the resin uptake ability of specimens prepared with a Z810 3D printer is examined.

Distribution of Urokinase Among the Common Mammals

1957 ◽  
Vol 192 (1) ◽  
pp. 186-190 ◽  
Author(s):  
Stanley R. Mohler ◽  
D. Robert Celander ◽  
M. Mason Guest
Keyword(s):  
Phosphate Buffer ◽  
Borate Buffer ◽  
Assay System ◽  
Distilled Water ◽  
Two Stage ◽  
Cold Acetone ◽  
The Common

Urokinase, a principle capable of activating profibrinolysin to fibrinolysin, has been found in the urine of the cat, rat, cow, rabbit, man, dog and hamster. Soluble concentrates of this activator were prepared by precipitation of urine with equal volumes of cold acetone, suspension of the precipitate in borate buffer and sequential dialysis of the suspension against borate buffer (ph 9.2), distilled water and phosphate buffer (ph 7.25). The ability of the urokinase concentrates from the urine of a given species to activate the profibrinolysin of its own and various other species was measured in a two-stage assay system which is described. The activation of profibrinolysin by urokinase was limited by definite species specificities and did not appear to involve the intermediation of a plasma prokinase.

scholarly journals EXPERIMENTAL OBSERVATIONS ON THE PATHOGENESIS OF GALL-BLADDER INFECTIONS IN TYPHOID, CHOLERA, AND DYSENTERY

1916 ◽  
Vol 24 (5) ◽  
pp. 497-514 ◽  
Author(s):  
Henry J. Nichols
Keyword(s):  
Gall Bladder ◽  
Sodium Bicarbonate ◽  
Common Duct ◽  
Portal System ◽  
Mesenteric Vein ◽  
The Common ◽  
Prevention And Cure

1. The theory of the production of gall-bladder lesions in typhoid, by descending infection of the bile from the liver receives support from investigations with the common duct fistula method in the rabbit. More bacilli appear in the bile with increased doses and more gall-bladder infections are obtained by increased doses. More bacilli appear in the bile after mesenteric vein injection than after ear vein injection and more lesions result under the first condition. More bacilli appear in the bile after injection of the same dose in immunized animals than in normal animals and more lesions also result in immunized animals. In cholera and dysentery the same mechanism is suggested with the additional factor of a portal system septicemia. 2. After the appearance of microorganisms in rabbit bile, their fate is apparently largely determined by the antiseptic properties of the bile. 100 per cent infections cannot be secured by intravenous doses large enough to insure the presence of microorganisms in the bile. Rabbit bile in vitro may be antiseptic to the microorganisms considered. The antiseptic action is largely due to its alkalinity. It is apparently possible to protect the rabbit to some degree against gall-bladder infection by a previous injection of sodium bicarbonate. 3. Alkaline therapy is suggested in the prevention and cure of gall-bladder carriers.

Kinetic studies on carbohydrates in alkaline conditions III. Interconversion of D-glucose, D-fructose and D-mannose in feebly alkaline solution

1955 ◽  
Vol 228 (1172) ◽  
pp. 100-119 ◽  
Keyword(s):  
Sodium Bicarbonate ◽  
Alkaline Solution ◽  
Kinetic Studies ◽  
Alternative Mechanism ◽  
Bicarbonate Buffer ◽  
First Order ◽  
Alkaline Conditions ◽  
The Common ◽  
Singly Charged ◽  
Reducing Substances

The interconversion of glucose, fructose and mannose in sodium carbonate-sodium bicarbonate buffer at pH 10.14 has been studied kinetically at 35 and 50° C. Degradation and the formation of other reducing substances also occur at significant rates and consideration of these reactions was necessary. The ratios of the three sugar concentrations become constant after a sufficient interval of time, and in these conditions the ratio [mannose]/ [glucose + fructose + mannose] was found to be 0.18 approximately, which is higher than has been previously reported. The reactions are shown to be first order in the concentrations of the three sugars, and the results are consistent with a mechanism in which these sugars form a common intermediate. The alternative mechanism, in which fructose is an intermediate in the interconversion of glucose and mannose, is not supported. A comparison with the experiments at much higher alkaiinities reported in parts I and II identifies the common intermediate with the singly charged enolate ion XH 2 - previously described. The comparison has enabled all the relevant velocity constants to be calculated. From these constants the rates of autoxidation of the sugars under the present conditions may be estimated; the results are shown to be in satisfactory agreement with observation. This supplies an additional check on the validity of the proposed mechanism. The latter is also shown to be consistent with the results of recent investigations on deuterium exchange in interconversion.

Seasonal Variations in Fecundity and Egg Size of The Common Goby, Pomatoschistus Microps

1989 ◽  
Vol 69 (3) ◽  
pp. 535-543 ◽  
Author(s):  
S.I. Rogers
Keyword(s):  
Breeding Season ◽  
Adult Life ◽  
Male Fish ◽  
Adult Life Span ◽  
The Common ◽  
Building Activities ◽  
Iteroparous Species ◽  
Sexually Mature ◽  
Brackish Water Fish ◽  
Common Goby

The common goby Pomatoschistus microps (Krøyer), is a small and abundant brackish water fish, which becomes sexually mature after the first winter of life and usually survives for only a single breeding season (Miller, 1975). During a protracted breeding season from approximately mid-April to August or September, the goby can produce up to 9 or 10 separate batches of eggs. It is therefore considered to be an iteroparous species, but because of the short adult life-span during which spawning occurs, this species has been termed an abbreviate iteropare (Miller, 1984). The nest-building activities of the male fish, courtship behaviour and subsequent brood-care are well documented (Vestergaard, 1976).

Data mining techniques

Acta Numerica ◽  
2001 ◽  
Vol 10 ◽  
pp. 313-355 ◽  
Author(s):  
Markus Hegland
Keyword(s):  
Data Mining ◽  
Efficient Algorithms ◽  
Data Sets ◽  
Mathematical Framework ◽  
Similar Data ◽  
Functional Relationships ◽  
New Methods ◽  
The Common ◽  
Data Objects ◽  
Data Collections

Methods for knowledge discovery in data bases (KDD) have been studied for more than a decade. New methods are required owing to the size and complexity of data collections in administration, business and science. They include procedures for data query and extraction, for data cleaning, data analysis, and methods of knowledge representation. The part of KDD dealing with the analysis of the data has been termed data mining. Common data mining tasks include the induction of association rules, the discovery of functional relationships (classification and regression) and the exploration of groups of similar data objects in clustering. This review provides a discussion of and pointers to efficient algorithms for the common data mining tasks in a mathematical framework. Because of the size and complexity of the data sets, efficient algorithms and often crude approximations play an important role.

scholarly journals THE FORMATION OF BASAL BODIES (CENTRIOLES) IN THE RHESUS MONKEY OVIDUCT

1971 ◽  
Vol 50 (1) ◽  
pp. 10-34 ◽  
Author(s):  
Richard G. W. Anderson ◽  
Robert M. Brenner
Keyword(s):  
Rhesus Monkey ◽  
Basal Body ◽  
Wall Material ◽  
Basal Bodies ◽  
Major Pathway ◽  
Tubule Formation ◽  
Body Formation ◽  
Body Production ◽  
Basal Foot ◽  
Section Analysis

Basal body replication during estrogen-driven ciliogenesis in the rhesus monkey (Macaca mulatta) oviduct has been studied by stereomicroscopy, rotation photography, and serial section analysis. Two pathways for basal body production are described: acentriolar basal body formation (major pathway) where procentrioles are generated from a spherical aggregate of fibers; and centriolar basal body formation, where procentrioles are generated by the diplosomal centrioles. In both pathways, the first step in procentriole formation is the arrangement of a fibrous granule precursor into an annulus. A cartwheel structure, present within the lumen of the annulus, is composed of a central cylinder with a core, spoke components, and anchor filaments. Tubule formation consists of an initiation and a growth phase. The A tubule of each triplet set first forms within the wall material of the annulus in juxtaposition to a spoke of the cartwheel. After all nine A tubules are initiated, B and C tubules begin to form. The initiation of all three tubules occurs sequentially around the procentriole. Simultaneous with tubule initiation is a nonsequential growth of each tubule. The tubules lengthen and the procentriole is complete when it is about 200 mµ long. The procentriole increases in length and diameter during its maturation into a basal body. The addition of a basal foot, nine alar sheets, and a rootlet completes the maturation process. Fibrous granules are also closely associated with the formation of these basal body accessory structures.

scholarly journals A state-of-the-art survey on semantic similarity for document clustering using GloVe and density-based algorithms

2021 ◽  
Vol 22 (1) ◽  
pp. 552
Author(s):  
Shapol M. Mohammed ◽  
Karwan Jacksi ◽  
Subhi R. M. Zeebaree
Keyword(s):  
Semantic Similarity ◽  
State Of The Art ◽  
Clustering Algorithms ◽  
Document Clustering ◽  
Accuracy Evaluation ◽  
Similar Data ◽  
Document Similarity ◽  
Density Based Clustering ◽  
Data Points ◽  
The Common

<p><span>Semantic similarity is the process of identifying relevant data semantically. The traditional way of identifying document similarity is by using synonymous keywords and syntactician. In comparison, semantic similarity is to find similar data using meaning of words and semantics. Clustering is a concept of grouping objects that have the same features and properties as a cluster and separate from those objects that have different features and properties. In semantic document clustering, documents are clustered using semantic similarity techniques with similarity measurements. One of the common techniques to cluster documents is the density-based clustering algorithms using the density of data points as a main strategic to measure the similarity between them. In this paper, a state-of-the-art survey is presented to analyze the density-based algorithms for clustering documents. Furthermore, the similarity and evaluation measures are investigated with the selected algorithms to grasp the common ones. The delivered review revealed that the most used density-based algorithms in document clustering are DBSCAN and DPC. The most effective similarity measurement has been used with density-based algorithms, specifically DBSCAN and DPC, is Cosine similarity with F-measure for performance and accuracy evaluation.</span></p>

Ultrastructure of the flagellar roots in Chlamydomonas gametes

1984 ◽  
Vol 67 (1) ◽  
pp. 133-143
Author(s):  
R.L. Weiss
Keyword(s):  
Basal Body ◽  
Direct Contact ◽  
The Other ◽  
Basal Bodies ◽  
Flagellar Roots ◽  
Mating Structure ◽  
Membrane Extension ◽  
Microtubular Root ◽  
Basal Apparatus ◽  
Microtubular System

The cytoskeleton of Chlamydomonas reinhardtii gametes has been studied by electron microscopy. The microtubular system, consisting of four flagellar roots inserted into the basal apparatus, is shown to include two daughter basal bodies and two striated fibres, newly described in this report. One new fibre associates with the 3-over-1 root and is similar to its counterpart, the striated fibre of the 2-member root. These similar root fibres connect each daughter basal body to the V-shaped microtubular root pair. The other new striated fibre joins the daughter basal body to both flagellar roots and is similar to the proximal striated fibre. In mt+ gametes, the conventional root microtubules make direct contact with the doublet zone of the non-activated mating structure. During activation, doublet zone microfilaments associate with the daughter basal body and the finely striated fibre of the 3-over-1 root. These observations suggest that the cytoskeleton acts as a scaffolding for membrane extension by the mt+ mating structure microfilaments.

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