Sensory Receptors and Epidermal Structures of a Meiofaunal Turbellarian (Proseriata, Monocelididae, Minoninae)

1995 ◽  
Vol 43 (1) ◽  
pp. 69 ◽  
Author(s):  
K Rohde ◽  
NA Watson
Keyword(s):  
Basal Body ◽  
High Energy ◽  
The Body ◽  
Lateral Part ◽  
Basal Bodies ◽  
Sensory Receptors ◽  
Ecological Requirements ◽  
Morphological Studies ◽  
Epidermal Surface ◽  
Eastern Australia

The senogram (set of sensory receptors) of a proseriate turbellarian from the meiofauna of a high-energy beach in south-eastern Australia is described, based on serial ultrathin sections. It comprises a pair of rhabdomeric eyes that lack a pigment cup, a statocyst located ventro-anteriorly to the brain and consisting of one lithocyte with a single ovoid statolith in the electron-lucent cytoplasm, several parietal and accessory cells and nerve fibres penetrating the statocyst capsule, and at least eight (and possibly eleven) types of epidermal receptors: A, an anterior and antero-lateral receptor with basal bodies and strongly branched processes (modified cilia); B, an 'insunk' collar receptor in all parts of the body surface, with eight microvilli surrounding the single cilium; C, a ciliary bundle arising from basal bodies at the base of a deep pit, in anterior third of body; D, a bundle of dendrites, reaching the surface, in anterior third of body, possibly a protonephridial pore; E, a multiciliate receptor with long branched ciliary rootlets, in anterior and antero-lateral part of body; F, as for E but with a single rootlet; G, as for F but with a vertical and an oblique rootlet arising from the basal body (F and G are possibly modifications of E); H, a receptor with a single cilium and short rootlet, somewhat raised above the epidermal surface; I, a pharyngeal receptor with a short cilium; J, a pharyngeal receptor with a long cilium; K, an anterior receptor with a bulbous cilium. A single cilium or up to three cilia surrounded by a cytoplasmic tube may constitute a further receptor type. Most epidermal perikarya are 'insunk', and epidermal cilia have large anteriorly directed, very thin vertical rootlets and short 'spurs' at the basal body. Bundles of rootlets of epidermal cilia converge towards their tips, some tips located close to the epidermal surface; it is suggested that they may be directly stimulated by mechanical stimuli. The variety of receptors indicates that the animal must respond to a complex array of stimuli. It is stressed that morphological studies of sensory receptors are the basis for an understanding of their function and of the ecological requirements of a species.

Studies on the epidermis of Tamnocephala II. Epidermal sensory receptors of Temnocephala novae-zealandiae

1977 ◽  
Vol 25 (2) ◽  
pp. 187 ◽  
Author(s):  
JB Williams
Keyword(s):  
The Body ◽  
Sensory Receptors ◽  
Epidermal Surface ◽  
Striated Rootlet ◽  
Fibre Pattern

Uniciliate receptors occur on the body, tentacles and attachment disc of T. novae-zealandiae, often grouped in tufts or clusters. The free ends of the associated nerve processes project above the epidermal surface. Elongated microvilli are associated with the ciliary tufts. The receptive cilium has the typical 9+2 fibre pattern and a striated rootlet.

A localized region of basal body proliferation in growing cells of Dileptus visscheri (ciliata, gymnostomate)

1976 ◽  
Vol 20 (1) ◽  
pp. 115-133
Author(s):  
J. Kink
Keyword(s):  
Cell Size ◽  
Basal Body ◽  
Growth Zone ◽  
The Body ◽  
Basal Bodies ◽  
Large Numbers

In the ciliate Dileptus organisms are completely organized at the time of excystation. They grow intensively, increasing in volume several times, before they reach the trophic cell size. The growth includes both the somatic part of the body as well as the oral parts, consisting of the cytostomal field and the ventral band of the proboscis. From the time of excystation, during the growth of the cell, the oral apparatus is able to capture and ingest food. Growth of an oral apparatus while functioning has not previously been reported in cilates. The proliferation of new oral kinetosomes in the growing oral apparatus occurs only in the cytostomal field. There is no proliferation of ciliature in the oral kineties of the growing proboscis. In those regions of the somatic kineties bordering the cytostomal field an extensive proliferation of somatic ciliature takes place. The zone of proliferation common to the oral and somatic ciliature supplies new kinetosomes for the elongating proboscis, the growing oral apparatus and the growth of the rest of the body. The mode of proliferation of the oral kinetosomes differs from that of the somatic kinetosomes. The oral kinetosomes form randomly in large numbers, appearing similar to an anarchic field such as is found in other ciliates. The somatic kinetosomes always arise singly and in a defined position in relation to the mature kinetosome. The proliferation of basal bodies in a defined area in Dileptus suggests the existence of a growth zone localized around the cytostomal field.

Ciliary coordination in newt lung cells requires microtubule-based linkages between basal bodies: A correlative light and EM study

1992 ◽  
Vol 50 (1) ◽  
pp. 570-571
Author(s):  
Robert Hard ◽  
Gerald Rupp ◽  
Matthew L. Withiam-Leitch ◽  
Lisa Cardamone
Keyword(s):  
Basal Body ◽  
Untreated Control ◽  
Beat Frequency ◽  
Primary Cultures ◽  
Living Cells ◽  
Power Stroke ◽  
Ultrastructural Changes ◽  
Lung Cells ◽  
Basal Bodies ◽  
Ciliated Cells

In a coordinated field of beating cilia, the direction of the power stroke is correlated with the orientation of basal body appendages, called basal feet. In newt lung ciliated cells, adjacent basal feet are interconnected by cold-stable microtubules (basal MTs). In the present study, we investigate the hypothesis that these basal MTs stabilize ciliary distribution and alignment. To accomplish this, newt lung primary cultures were treated with the microtubule disrupting agent, Colcemid. In newt lung cultures, cilia normally disperse in a characteristic fashion as the mucociliary epithelium migrates from the tissue explant. Four arbitrary, but progressive stages of dispersion were defined and used to monitor this redistribution process. Ciliaiy beat frequency, coordination, and dispersion were assessed for 91 hrs in untreated (control) and treated cultures. When compared to controls, cilia dispersed more rapidly and ciliary coordination decreased markedly in cultures treated with Colcemid (2 mM). Correlative LM/EM was used to assess whether these effects of Colcemid were coupled to ultrastructural changes. Living cells were defined as having coordinated or uncoordinated cilia and then were processed for transmission EM.

Digestibility of nutrients and milk productivity of cows when using the concentrate mixture with the inclusion of rapeseed presscake

2020 ◽  
pp. 48-53
Author(s):  
L. Yarmots ◽  
G. Yarmots ◽  
A. Belenkaya
Keyword(s):  
Protein Digestibility ◽  
High Energy ◽  
Negative Influence ◽  
The Body ◽  
Milk Productivity ◽  
Lactating Cows ◽  
Low Protein ◽  
Concentrate Mixture ◽  
Almost All ◽  
Experimental Group

For ruminants, especially high-yielding animals in addition to the complete supply of animals with protein, its digestibility in the rumen is important. With low protein digestibility in the rumen, the released ammonia will be more effectively used by the rumen microflora, and the undigestible protein in the subsequent sections of the digestive tract can serve as a source of amino acids for the body. The use of concentrate mixtures with the inclusion of local, affordable and cheaper grain feeds, in particular a high-energy and protein ingredient- rapeseed presscake makes it possible to increase the milk productivity of cows throughout lactation. These presscakes are well balanced in their amino acid composition and belong to feeds whose protein has a low degree of digestibility in the rumen. The purpose of the researches was to study the digestibility of nutrients and milk productivity of cows when using the concentrate mixture with the inclusion of rapeseed presscake. In the scientific and economic experiment has been carried out on lactating cows, where the cows of the experimental group in the concentrate mixture of peas has been replaced with rapeseed presscake the digestibility of nutrients in the ration, energy metabolism and milk productivity have been studied. Studies have shown that almost all the nutrients were significantly better digested by the animals of the experimental group. Energy in milk was more allocated by cows of the experimental group by 6,29 MJ. From cows of the experimental group for 100 and 305 days of lactation has been obtained more milk by 6,27 and 7,06 %, respectively, than from control herdmates. The biochemical parameters of blood were within the limits of the physiological norm in animals of both groups. Thus, the replacement of peas with rapeseed presscake in the concentrate mixture did not have a negative influence on the metabolic processes and helped to increase the milk productivity of cows.

scholarly journals Spectral Decomposition and Sound Source Localization of Highly Disturbed Flow through a Severe Arterial Stenosis

2021 ◽  
Vol 8 (3) ◽  
pp. 34
Author(s):  
Fardin Khalili ◽  
Peshala T. Gamage ◽  
Amirtahà Taebi ◽  
Mark E. Johnson ◽  
Randal B. Roberts ◽  
...  
Keyword(s):  
Spectral Decomposition ◽  
Pressure Fluctuations ◽  
Flow Analysis ◽  
High Energy ◽  
Arterial Stenosis ◽  
Epidermal Surface ◽  
Flow Through ◽  
Processing Techniques ◽  
Proper Orthogonal ◽  
Signal Processing Techniques

For the early detection of atherosclerosis, it is imperative to explore the capabilities of new, effective noninvasive diagnosis techniques to significantly reduce the associated treatment costs and mortality rates. In this study, a multifaceted comprehensive approach involving advanced computational fluid dynamics combined with signal processing techniques was exploited to investigate the highly turbulent fluctuating flow through arterial stenosis. The focus was on localizing high-energy mechano-acoustic source potential to transmit to the epidermal surface. The flow analysis results showed the existence of turbulent pressure fluctuations inside the stenosis and in the post-stenotic region. After analyzing the turbulent kinetic energy and pressure fluctuations on the flow centerline and the vessel wall, the point of maximum excitation in the flow was observed around two diameters downstream of the stenosis within the fluctuating zone. It was also found that the concentration of pressure fluctuation closer to the wall was higher inside the stenosis compared to the post-stenotic region. Additionally, the visualization of the most energetic proper orthogonal decomposition (POD) mode and spectral decomposition of the flow indicated that the break frequencies ranged from 80 to 220 Hz and were correlated to the eddies generated within these regions.

scholarly journals Innovative concepts for the usage of veneer-based hybrid materials in vehicle structures

2021 ◽  
pp. 146442072199839
Author(s):  
DB Heyner ◽  
G Piazza ◽  
E Beeh ◽  
G Seidel ◽  
HE Friedrich ◽  
...  
Keyword(s):  
Steel Strip ◽  
High Energy ◽  
The Body ◽  
Vehicle Body ◽  
Material System ◽  
Laminated Veneer Lumber ◽  
Hybrid Beam ◽  
Bending Load ◽  
The Impact ◽  
Very High

A promising approach for the development of sustainable and resource-saving alternatives to conventional material solutions in vehicle structures is the use of renewable raw materials. One group of materials that has particular potential for this application is wood. The specific material properties of wood in the longitudinal fiber direction are comparable to typical construction materials such as steel or aluminum. Due to its comparatively low density, there is a very high lightweight construction potential especially for bending load cases. Structural components of the vehicle body are exposed to very high mechanical loads in the case of crash impact. Depending on the component under consideration, energy has to be absorbed and the structural integrity of the body has to be ensured in order to protect the occupants. The use of natural materials such as wood poses particular challenges for such applications. The material characteristics of wood are dispersed, and depend on environmental factors such as humidity. The aim of the following considerations was to develop a material system to ensure the functional reliability of the component. The test boundary conditions for validation also play a key role in this context. The potential of wood–steel hybrid design based on laminated veneer lumber and steel was investigated for use in a component subjected to crash loads such as the door impact beam. The chosen solution involves a separation of functions. A laminated veneer lumber-based beam was hybridized with a steel strip on the tension side. The steel strip was designed to compensate the comparatively low elongation at fracture of the wood and to ensure the integrity of the beam. The wooden component was designed for high energy absorption due to delamination and controlled failure during the impact, while maintaining the surface moment of inertia, i.e. the bending stiffness of the entire component. This approach was chosen to ensure the functional safety of the component, avoid sudden component failure and utilize the high potential of both materials. The tests carried out provided initial functional proof of the chosen solution. The hybridization achieved significantly higher deformations without sudden failure of the beam. In addition, bending capabilities were increased significantly compared to a beam without hybridization. In comparison with a state-of-the-art steel beam, the hybrid beam was not able to achieve the maximum deformation and the target weight of the hybrid beam. Further optimization of the hybrid beam is therefore necessary.

Body Composition Modifications Due to the “Search, Rescue and Survival Training” in Male Military Firefighter Cadets

2021 ◽  
Author(s):  
Thiago Ramos de Barros ◽  
Verônica Pinto Salerno ◽  
Thalita Ponce ◽  
Míriam Raquel Meira Mainenti
Keyword(s):  
Body Composition ◽  
Body Weight ◽  
Repeated Measures ◽  
Food Restriction ◽  
Physical Exertion ◽  
High Energy ◽  
The Body ◽  
Fat Free Mass ◽  
Sleep Restriction ◽  
Fat Percentage

ABSTRACT Introduction To train and prepare cadets for a career as firefighters in Rio de Janeiro, the second-year students of the Officers Training Course are submitted to a Search, Rescue, and Survival Training (SRST) course, which is characterized by long periods of high physical exertion and sleep restriction during a 9-day instruction module, and food restriction during a 7-day survival module. The present study investigated changes in the body composition of 39 male cadets submitted to SRST during training and 4 weeks of recovery with no restrictions in food consumption. Materials and Methods Each cadet was evaluated by anthropometric measurements at six time points: pre-SRST; after the first module; after the second module; and after 1, 2, and 4 weeks of recovery. Measurements included body girths and skinfolds, to estimate trunk (chest and waist) and limbs (arm and thigh) dimensions, as well as body composition. Repeated measures ANOVA and Friedman test were applied (depending on each data distribution). Results Statistically significant decreases in body weight (76.2; 69.8-87.2 to 63.9; 58.9-73.5 kg) and fat free mass (FFM, 69.2; 63.7-77.2 to 60.1; 56.2-68.0 kg) were observed following the second module of SRST. Following a single week of recovery, the FFM returned to pre-SRST values. Body weight returned to pre-training levels in 2 weeks. Body fat percentage and mass also significantly decreased during SRST (9.0; 7.7-12.3 to 6.5; 5.1-9.3% and 6.9; 5.6-10.0 to 6.9; 5.6-10.0 kg, respectively), which showed a slower and more gradual recovery that reached pre-SRST values after 4 weeks. The girths of arm, thigh, chest and waist significantly decreased due to SRST. The girths of the limbs (arm and thigh) returned to pre-training values after one month of recovery, while the girths of the trunk (chest and waist) did not return to pre-SRST values during the study period. Conclusions The findings suggest that men who experience periods of high energy demands and sleep restriction followed by a period of food restriction will endure unavoidable physical consequences that can be mostly reversed by a 1-month recovery.

scholarly journals MORPHOLOGICAL STUDIES IN EXPERIMENTAL CRETINISM

1913 ◽  
Vol 17 (6) ◽  
pp. 636-652 ◽  
Author(s):  
Arthur L. Tatum
Keyword(s):  
Adrenal Glands ◽  
The Body ◽  
The Other ◽  
Degenerative Changes ◽  
Morphological Studies ◽  
Cellular Changes ◽  
Anatomical Basis ◽  
Parenchymatous Organ ◽  
Islands Of Langerhans

In summarizing the findings of this paper it may be said that degenerative changes have been noted in practically every parenchymatous organ. Among these the most striking has been that of serous imbibition by the most active cells of these organs. In regard to the changes in the glands of internal secretion, the findings corroborate the statements of Cushing in regard to hypophysectomy, that removal of one gland of internal secretion results in changes in all the other glands. In this case, degenerative changes predominate in the hypophysis, thymus, ovary, and testis, while hyperplasia is seen in the islands of Langerhans and the medullas of the adrenal glands. Finally, in the rabbit athyroidism is responsible for grave degenerative changes in practically all organs and tissues of the body, and many of the symptoms of cretinism have an anatomical basis in organic cellular changes.

scholarly journals A Ten-Year Review of Primary School Flexible Learning Environments: Interior Design and IEQ Performance

Buildings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 183
Author(s):  
Diksha Vijapur ◽  
Christhina Candido ◽  
Özgür Göçer ◽  
Shirley Wyver
Keyword(s):  
Primary School ◽  
Learning Environments ◽  
Interior Design ◽  
High Energy ◽  
The Body ◽  
Learning Activities ◽  
Indoor Environmental Quality ◽  
Flexible Learning ◽  
Physical Infrastructure ◽  
And Performance

Flexible Learning Environments (FLEs) arose as enablers for implementation of student-centric pedagogical approaches. Interior design is the key to the success of FLEs, providing the physical infrastructure needed for students to engage on several learning activities, from individual to group work, which take place in a variety of zones ranging from low to high energy. Therefore, a harmonious synergy between the interior design and subsequent Indoor Environmental Quality (IEQ) performance of FLEs’ physical configuration and learning activities is needed. The objective of this paper is to systematically review (in accordance with the PRISMA method) existing literature related to FLEs within primary school settings, typically catering to children aged 5–12 years old, to understand the body of work investigating the design and performance of FLEs over the last decade (2010–2020). Key findings suggest that the proximity and acoustic and visual permeability of zones found in FLEs may give rise to inadequate IEQ conditions delivered to students. In addition, it could be inferred from the results of the literature review that interior design and IEQ have not been sufficiently investigated in an integrated manner.

Structural Analysis of Basal Bodies of The Isolated Oral Apparatus of Tetrahymena Pyriformis

1970 ◽  
Vol 6 (3) ◽  
pp. 679-700
Author(s):  
J. WOLFE
Keyword(s):  
Structural Analysis ◽  
Cell Membrane ◽  
Basal Body ◽  
Structural Integrity ◽  
Tetrahymena Pyriformis ◽  
Basal Plate ◽  
Basal Bodies ◽  
The Third ◽  
Ionic Detergent

The oral apparatus of Tetrahymena pyriformis was isolated using a non-ionic detergent to disrupt the cell membrane. The mouth consists largely of basal bodies and microfilaments. Each basal body is attached to the mouth by a basal plate which is integrated into the meshwork of microfilaments that confers upon the oral apparatus its structural integrity. Each basal body is composed of 9 triplet microtubules. Two of the 3 tubules, subfibres ‘A’ and ‘B’ are composed of filamentous rows of globules with a spacing of 4.5nm. The third tubule, subfibre ‘C’, is only one-third the length of the basal body.

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