Electrode for selective recording of electromyograms from intercostal muscles

1989 ◽  
Vol 67 (5) ◽  
pp. 2125-2128 ◽  
Author(s):  
W. A. Whitelaw ◽  
D. R. Markham
Keyword(s):  
Animal Experiments ◽  
The Other ◽  
Bipolar Electrode ◽  
Metal Foil ◽  
Intercostal Muscle ◽  
Recording Electrode ◽  
Electrical Field ◽  
Single Motor Unit ◽  
Minimal Trauma ◽  
Wire Hook

An electromyogram-recording electrode is described that makes it possible to record separately the electrical signals generated within two closely approximated muscle layers. The device consists of two bipolar wire hook electrodes embedded in opposite faces of a thin laminated plastic wafer. The middle lamina of the wafer is a sheet of metal foil that shields the electrical field on one side of the wafer from the bipolar electrode on the other side. The device was tested by inserting it from the inside of the chest wall between the internal and external intercostal muscle layers. Signals from the two muscle layers were clearly separated. Single motor unit spikes were attenuated by factors ranging from 41 to 2.4. The device can be implanted with minimal trauma to surrounding muscles and is suitable for chronic animal experiments.

Us and Them : Scientists' and Animal Rights Campaigners' Views of the Animal Experimentation Debate

1995 ◽  
Vol 3 (1) ◽  
pp. 1-21 ◽  
Author(s):  
Elizabeth S. Paul
Keyword(s):  
Decision Making ◽  
Animal Rights ◽  
Animal Experiments ◽  
Animal Experimentation ◽  
The Other ◽  
Decision Making Processes ◽  
Opposing Group ◽  
Relative Capacity ◽  
Extreme View

AbstractAnimal rights campaigners and scientists working with animals completed anonymous questionnaires in which they were asked to report, not only on their own beliefs and ideas about the animal experimentation debate, but also on those they perceived the opposing group to hold. Both groups of participants tended to have a negative and somewhat extreme view of the other. But they did have an accurate grasp of the arguments and defenses commonly offered on both sides of the debate, and showed some agreement concerning the relative capacity of different animals to suffer. Differences appeared in the level of the phylogenetic hierarchy at which participants thought animals might be capable of suffering, and in their decision-making processes regarding the admissibility of animal experiments.

scholarly journals Supraperiosteal Flap Technique versus Mucoperiosteal Flap Technique in Cleft Palate Surgery

1996 ◽  
Vol 33 (6) ◽  
pp. 501-506 ◽  
Author(s):  
Thomas S. Leenstra ◽  
Gen-Iku Kohama ◽  
Anne M. Kuijpers-Jagtman ◽  
Hans Peter M. Freihofer
Keyword(s):  
Clinical Study ◽  
Animal Experiments ◽  
The Other ◽  
Future Research ◽  
Deciduous Dentition ◽  
Postoperative Course ◽  
Flap Technique ◽  
Alveolar Development ◽  
Different Types ◽  
Mucoperiosteal Flap

Recent animal experiments have shown that palatal repair without denudation of bone leads to a superior dento-alveolar development. The aim of this clinical study was to evaluate the peri- and postoperative course and the dento-alveolar development of the deciduous dentition in Japanese ULCP, and CP patients up to 5 years after two different types of palatal repair. One of the methods, the Kohama (1991) supraperiosteal flap technique, Is performed without denudation of the bony palate, while the other, the Wardill (1937) push-back technique, results in areas of denuded bone. It was concluded that the supraperiosteal technique can be performed successfully in approximately the same amount of time as the push-back technique. Re-epithelialization of the wound areas after supraperiosteal repair takes about 1 week, which is one third of the time associated with healing after the push-back technique. Arch depth of the deciduous dentition after the supraperiosteal technique is superior compared to the push-back technique. The question of whether or not the supraperiosteal technique produces more favorable dento-alveolar development than the mucoperiosteal technique in the permanent dentition in humans has to be elucidated in future research.

Experimental Study of Melt Electrospinning in Parallel Electrical Field

2011 ◽  
Vol 221 ◽  
pp. 111-116 ◽  
Author(s):  
Ming Feng Hao ◽  
Yong Liu ◽  
Xue Tao He ◽  
Peng Cheng Xie ◽  
Wei Min Yang
Keyword(s):  
Experimental Study ◽  
Field Strength ◽  
Electric Field ◽  
Electric Field Strength ◽  
Melt Spinning ◽  
Fiber Diameter ◽  
The Other ◽  
Electrical Field ◽  
Melt Electrospinning ◽  
Plate Area

In this paper, self-designed electrospinning equipment was used to make a series of electrospinning experiments with materials of polypropylene. The influences of the receiver area, the upper plate area, and the overlapping area between the receiver and the upper plate, on the melt spinning electric field, the spinning efficiency, and the fiber diameter, were investigated respectively. The results showed that when the other parameters were kept unchanged, with the increase of the receiver’s diameter, the electric field strength and spinning efficiency increased, and the fiber diameter increased at first and then decreased; the bigger the overlapping area between the receiver and the upper plate, the more stable the vertical spinning path.

Design of a Lengthening Element for a Modular Femur Endoprosthetic System

1989 ◽  
Vol 203 (2) ◽  
pp. 97-102 ◽  
Author(s):  
G J Verkerke ◽  
H Schraffordt Koops ◽  
R P H Veth ◽  
J Oldhoff ◽  
H K L Nielsen ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Early Stage ◽  
Animal Experiments ◽  
Malignant Tumour ◽  
The Other ◽  
University Hospital ◽  
In Vitro Tests ◽  
Adjacent Tissue ◽  
Non Invasive

A malignant tumour may develop around the knee joint of a child. In the majority of cases it will then be necessary to resect the involved bone with adjacent tissue. A joint team of Groningen University Hospital and University of Twente is currently working on the project of developing a modular endoprosthetic system to bridge the defect resulting from the resection. Since the other, normal, leg continues to grow, the endoprosthetic system will have to include an element the length of which can be adjusted non-invasively. The main conditions to be met by the lengthening element are non-invasive continuous adjustability and a maximum total lengthening of 114 mm. This was achieved by using an external magnetic field. Animal experiments showed that the lengthening element worked well, although moisture infiltrated the telescopic tubes and the lengthening element was covered by proliferating bone at an early stage. Also, the necessary magnetic field proved to be larger than calculated. In a revised design, these problems are resolved. In vitro tests show that the new lengthening element meets all requirements.

scholarly journals POLARIZED INTERCELLULAR BRIDGES IN OVARIAN FOLLICLES OF THE CECROPIA MOTH

1973 ◽  
Vol 58 (1) ◽  
pp. 172-188 ◽  
Author(s):  
Richard I. Woodruff ◽  
William H. Telfer
Keyword(s):  
Nurse Cell ◽  
Electrical Potential ◽  
The Other ◽  
Rabbit Serum ◽  
Nurse Cells ◽  
Recording Electrode ◽  
Serum Globulin ◽  
Intercellular Bridges ◽  
Apical Cytoplasm ◽  
Unidirectional Movement

Fluorescein-labeled rabbit serum globulin was injected into vitellogenic oocytes of the cecropia moth. Though the label spread throughout the ooplasm in less than 30 min, it was unable even after 2 h to cross the complex of intercellular bridges connecting the oocyte to its seven nurse cells. After injection into a single nurse cell, fluorescence was detected in the oocyte adjacent to the bridge complex within 3 min and had spread throughout the ooplasm in 30 min. Here also, the cell bodies of the six uninjected nurse cells remained nonfluorescent. Four of the nurse cells are not bridged directly to the oocyte but only through the apical ends of their siblings. Unidirectional movement must therefore occur in the apical cytoplasm of the nurse cells, as well as in the intercellular bridges. The nurse cells of healthy follicles had an intracellular electrical potential -40 mV relative to blood or dissecting solution, while oocytes measured -30 mV. A mV difference was also detected by direct comparison between a ground electrode in one cell and a recording electrode in the other. Three conditions were found in which the 10 mV difference was reduced or reversed in polarity. In all three cases fluorescent globulin was able in some degree to cross the bridges from the oocyte to the nurse cells.

Comparative study of β-tricalcium phosphate mixed with platelet-rich plasma versus β-tricalcium phosphate, a bone substitute material in dentistry

2003 ◽  
Vol 51 (4) ◽  
pp. 475-484 ◽  
Author(s):  
Katalin Kovács ◽  
N. Velich ◽  
T. Huszár ◽  
G. Szabó ◽  
G. Semjén ◽  
...  
Keyword(s):  
Tricalcium Phosphate ◽  
Bone Substitute ◽  
Platelet Rich Plasma ◽  
Autologous Blood ◽  
Animal Experiments ◽  
The Other ◽  
Beagle Dogs ◽  
Bone Substitute Material ◽  
Substitute Material

Animal experiments were carried out with osteoconductive bone substitute β-tricalcium phosphate (β-TCP), with the aim of assessing the effects of the growth factors synthesised by thrombocytes on the speed of β-TCP incorporation and on the quality of newly formed bone. The question to be answered was the extent to which platelet-rich plasma (PRP) accelerated the resorption of β-TCP and the formation of new bone. Two teeth were removed symmetrically from each side of the mandible of 12 Beagle dogs; the resulting cavities were filled on one side with β-TCP alone, and on the other side with a mixture of β-TCP + PRP (obtained from autologous blood). The quality of the newly formed bone and the effects of this PRP were studied by histological and histomorphometric methods. In week 6, bone formation was already more effective when PRP was applied in comparison with β-TCP alone, and in week 12 the growth was significantly greater. The results demonstrate that the use of PRP accelerates the remodelling of new bone created by β-TCP.

scholarly journals OBSERVATIONS ON MIXTURES OF ELEMENTARY BODIES OF VACCINIA AND COATED COLLODION PARTICLES BY MEANS OF ULTRACENTRIFUGATION AND ELECTROPHORESIS

1940 ◽  
Vol 72 (5) ◽  
pp. 523-529 ◽  
Author(s):  
J. E. Smadel ◽  
E. G. Pickels ◽  
T. Shedlovsky ◽  
T. M. Rivers
Keyword(s):  
The Other ◽  
Rabbit Serum ◽  
Soluble Antigen ◽  
Normal Rabbit Serum ◽  
Electrical Field ◽  
Heat Stable ◽  
Other Hand ◽  
Single Boundary

It has been shown experimentally that mixtures of two types of particles, namely, elementary bodies of vaccinia and collodion particles coated with protein, sediment with a single boundary in the analytical centrifuge. Such mixtures have been shown to develop one or two boundaries on electrophoresis in the Tiselius apparatus, depending on the type of coating on the surface of the collodion particles. When covered with the heat-stable soluble antigen of vaccinia, collodion particles migrate in the electrical field at the same rate as elementary bodies. On the other hand, if they are coated with a component of normal rabbit serum, they migrate at a different rate. The estimation of purity of preparations of virus by means of data obtained by ultracentrifugation and electrophoresis is discussed.

The Significance of Dopamine for the Mode of Action of Neuroleptics and the Pathogenesis of Schizophrenia

1977 ◽  
Vol 130 (5) ◽  
pp. 463-474 ◽  
Author(s):  
H. M. van Praag
Keyword(s):  
Side Effects ◽  
Clinical Research ◽  
Mode Of Action ◽  
Chemical Structure ◽  
Animal Experiments ◽  
The Other ◽  
Therapeutic Effects ◽  
Supporting Evidence ◽  
Pathogenetic Mechanism ◽  
The One

SummaryAnimal experiments have demonstrated the likelihood that all known neuroleptics inhibit transmission in central CA-ergic systems, regardless of their chemical structure and via different mechanisms. For clinical psychiatry this fact prompts a number of questions: (1) is this phenomenon also to be found in human individuals; (2) if so, is it of importance for the clinical (side) effects of neuroleptics; (3) do patients with (schizophrenic) psychoses show signs of central CA-ergic hyperactivity ? This article presents a survey of clinical research focused on these questions which, for the sake of brevity, is confined to DA metabolism. The available data indicate the plausibility of a correlation between inhibition of DA-ergic transmission on the one hand, and on the other hand the therapeutic effects of neuroleptics and the occurrence of hypokinetic-rigid symptoms. The hypothesis that DA-ergic hyperactivity is an important pathogenetic mechanism in schizophrenic psychoses can be based only on indirect arguments; direct studies of the DA metabolism have so far failed to reveal supporting evidence. The possible causes of this failure are discussed.

Experimental Investigations on Microwave-Current Assisted Sintering Process and Oxidation of Graphite Die at High Temperature

2021 ◽  
Vol 18 (2) ◽  
Author(s):  
H. K. M. Al-Jothery ◽  
Thar M. Albarody ◽  
P. S. M. Megat-Yusof ◽  
N. Al-Shaibani ◽  
H. G. Mohammed
Keyword(s):  
Tensile Strength ◽  
High Temperature ◽  
High Ratio ◽  
The Other ◽  
Experimental Investigations ◽  
Sintering Process ◽  
High Melting Point ◽  
Electrical Field ◽  
Lack Of Information ◽  
Graphite Structure

In the current-assisted sintering technique, graphite is mainly used to fabricate die and other components (such as electrodes and spacers) because of its excellent thermoelectric properties, high melting point and high ratio of the tensile strength to the compressive strength. As widely known, graphite is one of the brittle materials, and the failure is difficult to be anticipated before it happens. Besides, there is a lack of information about the effects of sintering process, environment and impurity on the graphite structure of the furnace, especially the die, which is the weakest part of the graphite structure. Therefore, the effects of electrical field and oxidation on the graphite die of microwave-current assisted sintering apparatus were investigated at a high temperature of 600-1900 °C based on physical characteristics and mechanical strength. In this article, the spark discharge phenomenon was experimentally proved during the sintering process of nonconductive material. The tensile strength of the upper punch after the sintering process was 20.2% higher than the pristine one because of the transforming of micro-graphite to carbon nanotubes which increased with increasing the temperature. On the other hand, the tensile strengths of graphite lower punch and sleeve were slightly dropped. While, the oxidation of GW-6S graphite in the air caused a mass loss that led to the reduction in tensile and compressive strengths.

Problems in Applying Teratologic Observations in Animals to Man

PEDIATRICS ◽  
1974 ◽  
Vol 53 (5) ◽  
pp. 820-820
Author(s):  
Josef Warkany
Keyword(s):  
Congenital Malformations ◽  
Animal Studies ◽  
Animal Experiments ◽  
Strain Differences ◽  
The Other ◽  
Human Beings ◽  
Vitamin Deficiencies ◽  
Long Time ◽  
Genetic And Environmental Factors ◽  
Experimental Teratology

In teratology you will have to deal with the question of the relation between animal experiments and legislative regulation. As one who has long been interested in human malformations and who has been in experimental teratology for 35 years, I will tell you about the application of animal experiments to human situations. Thirty-five years ago it was discovered that vitamin deficiencies were reliable teratogenic procedures, yet I have not seen any comparable effects in human beings. In 1959 we found that salicylates are excellent teratogens in rats. I still have not seen a child who was deformed by salicylates. With thalidomide, the situation is the other way around; its teratogenicity was first discovered in man and then one had to find susceptible animals. These experiences exemplify how cautious one must be in applying animal observations to man. I do not say that the animal studies were in vain. They gave us important concepts about general principles of teratogenesis, but one cannot simply apply observations in mice, rats, or monkeys to man. Yet, it is done all the time. We have also learned from experimentation about the variability of response in different species, and even within species there are strain differences in susceptibility. Furthermore, we have learned that a combination of genetic and environmental factors play an important role in the production of congenital malformations, as has been well demonstrated in mice in which cleft palate was produced by cortisone in certain but not all strains. Those who have been in the field for a long time are most hesitant in applying animal results to man.

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