Influence of temperature on the reproduction of Damalinia equi (Denny)

1963 ◽  
Vol 11 (2) ◽  
pp. 183 ◽  
Author(s):  
MD Murray
Keyword(s):  
Skin Temperature ◽  
High Temperatures ◽  
Atmospheric Temperature ◽  
Early Spring ◽  
The Body ◽  
The Sun ◽  
Hair Coat ◽  
Influence Of Temperature ◽  
Influence Of Temperature On

No development of the egg within the female Damalinia equi (Denny) occurred at 16�C. Most eggs were laid at 36�C at R.H.'s of 75% or less, but after an exposure to 44.5�C for only 1 hr females did not lay eggs. Morphogenesis proceeded to an advanced state from 27-39�C, but its completion and the subsequent hatching of the embryo only took place from 31-39�C provided the R.H. was less than 90%. A R.H. of 90% prevented hatching of the eggs. Exposure of eggs to 49�C for 2 hr was lethal. The skin temperature of the horse is influenced considerably by atmospheric temperature. The abundance of D. equi on the bodies of horses in early spring is probably due to the temperatures near the skin of the body being continuously favourable for reproduction of D. equi during the winter. Exposure to the sun can cause the temperatures within the hair coat on the upper aspects of the body to become higher than 44.5�C for more than an hour and thus can retard reproduction. The accumulative effect of repeated high temperatures could prevent an increase in the numbers of D. equi during the summer.

scholarly journals THE INFLUENCE OF TEMPERATURE ON THE ACTION OF STRYCHNIN IN FROGS

1913 ◽  
Vol 18 (3) ◽  
pp. 300-309 ◽  
Author(s):  
Thomas Stotesbury Githens
Keyword(s):  
Low Temperature ◽  
High Temperatures ◽  
Low Temperatures ◽  
Room Temperature ◽  
Drug Action ◽  
The State ◽  
Great Caution ◽  
Influence Of Temperature ◽  
Influence Of Temperature On

In order to establish the influence of temperature upon the effect of varying doses of strychnin injected into frogs, the animals must be kept under observation for several days and at various definite degrees of temperature. Statements that the animal was kept "cold," "at room temperature," or "warm" are insufficient. With a certain dose tetanus may result constantly at 30° C. yet never appear at 21° C., and either of these temperatures might be described as warm, when compared to a room temperature of 15° C. Furthermore an animal may apparently fail to respond in the cold to an injection of certain doses of strychnin and yet be found in tetanic convulsions the next day. That an animal may have late, long lasting, or strong tetanus while kept at such a low temperature as 5° C. after an injection of a dose of strychnin smaller than 0.01 of a milligram per frog emphasizes the fact that great caution must be exercised in formulating laws as to the influence of temperature on drug action. The main results of this investigation may be summarized as follows: Doses of strychnin amounting to 0.0006 of a milligram per gram of frog will cause tetanus at all temperatures between 5° C. and 30° C., although at low temperatures the tetanus may appear late. A dose of 0.0003 of a milligram per gram of frog will frequently produce tetanus at 5° C. as well as at 30° or 27° C., but may nevertheless fail to produce any reaction at such an intermediary temperature as 21° C. Smaller doses, 0.0002 of a milligram per gram, will cause tetanus in the cold but not at high temperatures. It may be stated in general that in frogs kept at low temperatures the tetanic state sets in later, continues longer, and each tetanic attack is of longer duration, while in the interval between the attacks the state of tonus is higher and the animals are more irritable than when they are kept at higher temperatures.

The distribution of the eggs of Mammalian Lice on their hosts. 3. The distriubtion of the eggs of Damalinia ovis (L) on the sheep.

1957 ◽  
Vol 5 (2) ◽  
pp. 173 ◽  
Author(s):  
MD Murray
Keyword(s):  
Vertical Distribution ◽  
Skin Temperature ◽  
Fibre Diameter ◽  
Atmospheric Temperature ◽  
The Body ◽  
Lateral Distribution ◽  
Temperature Zone ◽  
The Face ◽  
The Vertical Distribution ◽  
Main Factor

The eggs of Damalinia ovis (L.) are attached to the wool and hair fibres of the sheep and have a vertical and lateral distribution, i.e. they may be laid at different distances from the skin and their distribution over the body of the sheep may vary. The vertical distribution of the newly laid eggs of D. ovis is determined by the distance to which the temperature zone suitable for oviposition extends from the skin. This is regulated mainly by skin temperature, skin topography, the depth of the air blanket trapped within the fleece, and atmospheric temperature. Usually the eggs are laid within 1/4 in. of the skin. The factors which influence the lateral distribution are the presence of suitable fibres and temperatures for oviposition. Eggs are not laid on the bare areas of the body because fibres are absent. There are, however, few bare areas on the sheep. The bases of certain hairs on the face, legs, and axilla and inguinal regions are too large in diameter for oviposition but mingled with them are many fibres which are suitable. As there are no areas on the sheep which are entirely covered with hairs of unsuitable diameter for oviposition, fibre diameter has little influence on the lateral distribution of the eggs of D. ovis. When sheep are exposed to low atmospheric temperatures, the skin temperature of the extremities falls below that at which D. ovis can oviposit. Skin temperature is the main factor which determines the lateral distribution of the eggs of D. ovis on the sheep.

Influence of Temperature on Rate of Regeneration in the Time-graded Regeneration Field in Planarians

Development ◽  
1961 ◽  
Vol 9 (1) ◽  
pp. 159-166
Author(s):  
Agnes Brøndsted ◽  
H. V. Brøndsted
Keyword(s):  
The Body ◽  
Influence Of Temperature ◽  
High Point ◽  
Know How ◽  
Influence Of Temperature On ◽  
Temperature Levels ◽  
Species Specific ◽  
Head Regeneration

There exists in planarians a time-graded regeneration field for head regeneration (Brøndsted, 1946, 1956; A. & H. V. Brøndsted, 1952). The characteristics of this field, expressed by rate of regeneration, are species-specific. The existence of this field ensures harmonious regeneration from cuts everywhere in the body, as a cut will always expose a ‘high point’ where regeneration of a head starts with greatest speed, thus taking the lead in organization and at the same time inhibiting head-forming tendencies elsewhere in the blastema (Brøndsted, 1956). The factors underlying these characteristics of the field are unknown; the problems involved are being attacked from several angles in our laboratory. For the sake of this work it is of some interest to know how the different rates of regeneration at various levels in the time-graded fields might be influenced by various temperature levels. Material and Methods The experiments were carried out on two species differing greatly in the characteristics of their time-graded regeneration fields.

The Dynamic of an Autoparametrical System With Two Coupled Pendulums Connected by SMA Spring

2008 ◽  
Author(s):  
Danuta Sado ◽  
Krzysztof Gajos
Keyword(s):  
Shape Memory Alloys ◽  
Shape Memory ◽  
Equations Of Motion ◽  
Type System ◽  
The Body ◽  
System Response ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
Resistive Forces ◽  
Sma Spring

The nonlinear dynamics of a three degree of freedom autoparametric system with two pendulums connected by SMA (Shape Memory Alloys) spring in the neighborhood internal and external resonance is presented in this works. The system consists of the body of mass m1 which is hung on a spring and a damper, and two connected by SMA spring pendulums of the length 1 and masses m2 and m3 mounted to the body of mass m1. It is assumed, that the motion of the pendulums are damped by resistive forces. Shape memory alloys have ability to change their material properties, for example stiffness. The equations of motion have been solved numerically and there was studied the influence of temperature on the energy transfer between modes of vibrations. Solutions for the system response are presented for specific values of the parameters of system. It was shown that in this type system one mode of vibrations may excite or damp another mode, and that except different kinds of periodic vibrations there may also appear chaotic vibrations. It depends on various amplitudes of excitation, frequencies ratio and different system parameters. Also fundamental is the influence of temperature on response of the system. For the identification of the responses of the system various techniques, including chaos techniques such as bifurcation diagrams and time histories, power spectral densities (FFT), Poincare` maps and exponents of Lyapunov may be use.

scholarly journals ACOUSTIC EMISSION UNDER TEMPERATURE TESTS OF MATERIALS

Aviation ◽  
2005 ◽  
Vol 9 (4) ◽  
pp. 24-28 ◽  
Author(s):  
Vitalii Babak ◽  
Sergay Filonenko ◽  
Viktor Kalita
Keyword(s):  
Plastic Deformation ◽  
Acoustic Emission ◽  
High Temperatures ◽  
Low Temperatures ◽  
Theoretical Research ◽  
Influence Of Temperature ◽  
Intermediate Area ◽  
Influence Of Temperature On

The theoretical research of the influence of temperature on the parameters of the alteration of acoustic emission signals from plastic deformation is considered. It is shown that increasing temperatures cause an increase in the amplitude of acoustic emission signals in an area of low temperatures and a decrease in an area of high temperatures. At the same time, there is an intermediate area of temperatures in which the amplitude of acoustic emission signals remains constant when temperature is increased. As shown in the article, this fact is connected with the alteration of the process of plastic deformation.

scholarly journals Influence of Temperature on the Global Spread of COVID-19

2020 ◽  
Author(s):  
Indrani Roy
Keyword(s):  
East Asia ◽  
Cost Effective ◽  
Atmospheric Temperature ◽  
South East Asia ◽  
Influence Of Temperature ◽  
Cool Environment ◽  
Fast Spreading ◽  
Influence Of Temperature On ◽  
The Usa ◽  
Spreading Disease

This article investigated whether the atmospheric temperature had any role in the spread and vulnerability to COVID-19 worldwide and how that knowledge can be utilized to contain the fast-spreading disease. It highlighted that temperature was an important factor in transmitting the virus, and a moderately cool environment was the most favourable state for its susceptibility. In fact, the risk from the virus is reduced significantly in high temperature environment. Warm countries and places were likely to be less vulnerable. We identified various degrees of vulnerability based on temperature and specified countries for March and April. The maximum reported case, as well as death, was noted when the temperature was in the range of around 275°K (2°C) to 290°K (17°C). Countries like the USA, UK, Italy and Spain belonged to this category. The vulnerability was moderate when the temperature was less than around 275°K (2°C) and countries in that category were Russia, parts of Canada and few Scandinavian countries. For temperature 300°K (27°C) and above, a significantly lesser degree of vulnerability was noted. Countries from SAARC, South East Asia, the African continent and Australia fell in that category. In fact, when the temperature was more than 305°K (32°C), there was a unusually low number of reported cases and deaths. For warm countries, further analyses on the degree of vulnerability were conducted for the group of countries from SAARC and South East Asia and individual countries were compared. We also showed countries can switch from one vulnerability state to another based on the variability of temperature. We provided maps of temperature to identify countries of different vulnerability states in different months of the year. That influence of temperature on the virus and previous results of clinical trials with similar viruses gave us a useful insight that regulating the level of temperature can provide remarkable results to arrest and stop the outbreak. Based on that knowledge, some urgent solutions are proposed, which are practically without side effects and very cost-effective too.

Carvallo. Influence de la temperature sur la fatigue des nerfs moteurs de la grenouille. Journ. de Physiol. et. de pat-hol. generale. T II p. 549 1900. Influence of temperature on fatigue of motor nerves of a frog

1901 ◽  
Vol IX (2) ◽  
pp. 205-207
Author(s):  
D. Polumordvinov
Keyword(s):  
The Body ◽  
Influence Of Temperature ◽  
Body Tissues ◽  
Influence Of Temperature On ◽  
Motor Nerves

At the present time, there is a clearly expressed tendency to examine the activity of the nerves subject to other laws than those that govern the activity of the rest of the body tissues. Since the time of the study of Bernstein, Vvedensky and Bovdich, most of the physiologists speak out for the fatigue of the nerves.

Weiss. Influence des variations de temperature sur les periodes latentes du muscle, du nerf et de la moelle. Compt. rend, hebdom. des seances de la Societe de Biologie T. III No. 3 p. 51 1900. About the influence of temperature on the latent period of irritation of muscle, nerve and spinal cord

1901 ◽  
Vol IX (2) ◽  
pp. 204-205
Author(s):  
D. Polumordvinov
Keyword(s):  
Spinal Cord ◽  
Latent Period ◽  
High Temperatures ◽  
Muscle Tissue ◽  
Low Temperatures ◽  
Chemical Processes ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
Muscle Nerve ◽  
Living Tissues

The intensity of the chemical processes occurring in living tissues undergoes significant changes, the temperature of these tissues changes; on muscle tissue, this law can be demonstrated with greater clarity; It is known that when the temperature rises or falls, the muscle curve shrinks sharply, and the latent period of irritation lengthens for low temperatures and shortens for high temperatures. The duration of the latent period is thus associated with the rapidity of the appearance of chemical changes in the muscles and can serve, to a certain extent, as yardstick.

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