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1. 1.A thermal shuttle box was used to determined the high and low body temperatures at which the desert iguana, Dipsosaurus, shuttles between a cold and hot environment. The high and low body temperatures at shuttling, designed HBTS and LBTS, respectively, were recorded for 1 to 3 days. 2. 2.The mean and standard deviation of the HBTS's and LBTS's for each lizard is reported. The average mean HBTS is 41.7 ± 1.66°C and the average mean LBTS is 36.41 ± 1.12°C. The average of the standard deviation of the mean LBTS of each lizard (1.91 ± 0.40 S.D.) for 36 Dipsosaurus is 1.5 times the average of the S.D. of the mean HBTS (1.21 ± 0.29 S.D.). 3. 3.A linear regression analysis was done of the high and low body temperatures at shuttling for each lizard, to determine if the previous HBTS determined the subsequent LBTS (HBTS-LBTS correlation pair) and if the previous LBTS determined the following HBTS (LBTS-HBTS correlation pair). These two correlation pairs compose a correlation pair type for each lizard. Fifteen lizards regulated their high and low body temperatures at shuttling independently of each other. Thirteen lizards demonstrated at least one positive correlation pair while only eight lizards displayed at least one negative correlation pair. Different correlation pair types do occur in the same lizard between runs. The correlation pair types are independent of the ambient air temperature of the hot or cold sides of the shuttle box. 4. 4.The data obtained from the behavioral response of Dipsosaurus in a thermal shuttle box were combined with information from studies of the reptilian nervous system in order to propose a hypothetical neural model of behavioral thermoregulation.

Rabbits at ambient temperatures within the thermal neutral zone show two different metabolic responses to preoptic cooling. One response type is defined by a preoptic thermal sensitivity that shifts with ambient temperature and a 'set point' that remains constant. The other response type is defined by a set point that shifts with ambient temperature and a preoptic thermal sensitivity that remains constant. Both response types can be modeled by a single equation. Nonmetabolic thermoregulatory responses are not significantly different between the two response types.

In a pre- and posttest design an attempt was made to quantify sand flipping in the behaviorally aroused Northern elephant seal ( Mirounga angustirostris ). Following pretest a seal was approached by the experimenter in order to induce a conflict between attack and escape tendencies. Sand flipping occurred more frequently when a seal was aroused than when it was resting regardless of the amount of solar radiation, degree of wetness, wind speed, etc.

1. 1. Electrocardiograms were obtained from two unrestrained tuataras at body temperatures from 7 to 26°C. 2. 2. Heart rates were lower than previously reported for resting Sphenodon , but were similar to resting rates of large lizards. 3. 3. EGG intervals (P–R, R–T, P i –T f ) did not differ greatly from those of Iguana iguana , except that duration of ventricular depolarization was more sensitive to temperature in Sphenodon . 4. 4. In general, the electrocardiology of Sphenodon closely resembles that of squamate reptiles. 5. 5. An unusual feature was an occasional increase in the absolute duration of R–T when heart rate increased slightly in response to disturbance.

Moths ‘warm-up’ prior to flight at mean rates of 4·06° C./min. in Celerio lineata and 2·5° C./min. in Rothschildia jacobae. The abdominal temperature rises only 2−3° C. during activity. Oxygen consumption of torpid sphinx moths increases by a factor of 2·27 as temperature changes from 26° to 36° C. Oxygen consumption during ‘warm-up’ increases with duration of ‘warm-up’ from about 1000μl./g. min during the initial 30 sec. to nearly 1600μl./g. min. during the 3rd min. This increase compensates for increasing heat loss from the thorax during ‘warm-up’. When the moths are regulating thoracic temperature, oxygen consumption increases with decreasing air temperature from a mean of about 400 μl./g. min at 31° C. to about 650 μl./g. min. at 26° C Values of O2 consumption calculated from the cooling curve of C. lineata are about 85 % of the measured values of O2 consumption. The giant silk moth, Rothschildia jacobae, regulates thoracic temperature during activity between about 32° and 36°C. at ambient temperature from 17°to 29° C. Moths kept at high temperatures are active longer, have more periods of activity and expend more energy for thermoregulation than moths kept at low temperatures. Large moths increase metabolism during active periods to offset heat loss and thereby maintain a relatively constant internal temperature. In this regard they may be considered endothermic, like birds and mammals. We estimate that male moths use 10% of their stored fat for thermoregulation, while females may use 50 %.

The transition from the warm-up motor pattern to the flight motor pattern in the saturnid moth H. cecropia, is described. The transition from warm-up to flight was found to be dependent on the temperature of the thoracic ganglia. A model to account for the two different motor output patterns and the transition of the warm-up pattern to the flight pattern is proposed.

1. 1. Ground squirrels respond to heating of the preoptic area by decreasing metabolism and body temperature (Tb) 2. 2. The transient change in heat balance during preoptic heating indicates increased heat loss at air temperatures of 8 and 22°C but no change at 33°C. These effects are reversed after long-term displacements of preoptic temperature (Tp). 3. 3. Cooling of the preoptic area causes increased metabolism and body temperature with little change in heat balance at air temperatures of 8 and 22°C but marked decreases in heat balance at 33°C. 4. 4. Responses to changes in preoptic temperature are reversed when body temperature changes significantly because the preoptic thermoregulatory signal is somehow reset or over-ridden by input from deep-body receptors.

1. 1. Bats subjected to internal heating allow their body temperatures to rise passively. 2. 2. At an average body temperature of 35·6† C the blood vessels of the wings dilate and excess heat is transported out of the body. 3. 3. When the internal heat loading ceases, the wing temperature quickly falls to ambient temperature. 4. 4. This mechanism undoubtedly forms an important channel for heat dissipation in flying bats.

SYNOPSIS. Some insects adjust heat production and heat loss, while others depend upon adjustments in location and posture to regulate body temperature. Many activities oE insects are tuned to internal temperature. These two features predict that the nature and form of temperature control in insects interact strongly in adaptation to climate, energy demand, niche specialization, and population size of insects.

Definition of words and terms is basic to communication and understanding in crop science. This report cites the relevant articles and lists published in related fields and includes the previously published reports issued as mimeographs or articles on definitions by the Crop Terminology Committee

The alcoholysis of cellulose in solutions of sulfuric acid in ethanol and n-butanol is described; emphasis is placed on the reactions of a cellulose that is 97% disordered, as measured by an infrared-deuteration technique, but the reactions of several partially ordered celluloses are also investigated. Alcoholysis produces only very slight increases in hydrogen-bond order, and the rate of reaction is roughly related to the degree of hydrogen-bond disorder in the starting material. The reactivity of the 97% disordered cellulose is dependent upon the method of freeing the film from the non-aqueous media used in its preparation. This variable reactivity is not associated with differences in hydrogen-bond order or in the surface area of internal voids, capillaries, etc., as measured by nitrogen sorption and a nonswelling oxidation technique, but could be due to the existence of a very fine pore structure in some of the films.

The central nervous control of temperature regulation in the bat, Eptesicus fuscus, was evaluated by heating the preoptic-anterior hypothalamus (PO/AH) of active, unanaesthetized bats. Because bats are metabolically very variable, change in body temperature was used as the criterion of change in heat balance in response to change in brain temperature and change in wing temperature as an indicator of vasomotor changes.

1. Cloacal temperature was monitored via a thermocouple in unrestrained house sparrows before and after lesions were placed in and near the anterior hypothalamic/preoptic area (AH/POA). 2. Bilateral lesions in the AH/POA of house sparrows significantly impaired maintenance of constant body temperature below the thermoneutral zone. 3. Since this thermoresponsive area is required for thermoregulation, some degree of homology between the AH/POA of birds and mammals must exist.

Thoracic temperature in the moth, Hyalophora cecropia, is correlated with gross patterns of behaviour. The animal warms up to a minimum of 34·8 °C body temperature before initiating flight. The rate of warm-up is linear and the duration of the warm-up period increases with decreasing air temperature. Thoracic temperature at the initiation of flight and during maintained flight remain constant at any given air temperature, however, decreases 0·25 °C per °C gradient as air temperature is decreased. Distribution of the maximum and minimum thoracic temperatures during active periods indicate that the animal maintains its body temperature within a favourable range. The animal uses behavioural mechanisms to maintain the thoracic temperature within this range when the body temperature reaches the limits, 33·4 and 37·8 °C. The minimum thoracic temperature for flight (34·8 °C) and the shade-seeking temperature (38·5 °C) correspond closely to the limits predicted from the maximumminimum distribution of thoracic temperatures. The theoretical minimum and maximum rates of oxygen consumption were calculated from cooling curves and warm-up curves. Both rates increase when the gradient between body temperature and air temperature increases (air temperature is lowered, body temperature remains relatively constant). Directly measured rates of oxygen consumption in flying animals increase as air temperature decreases. These values fall within the calculated maximum and minimum in all cases. Oxygen consumption measured in torpid animals indicates a normal poikilo-thermic response, increasing with increased air temperature. The Q10 for this response is 2·25 over the range 20–30 °C. A model for the regulation of body temperature in active moths is discussed.

Experimental results indicate that certain configurations of discrete charges may be more stable than continuous distributions possessing the same charge and corresponding symmetries. A model of N identical infinitely long negatively charged rods rotating under the influence of a uniform applied magnetic field is here investigated for stability of perturbations about an equilibrium configuration and compared to a continuous charged sheet. For the continuous sheet, a countably infinite number of modes of oscillation are possible of which only a finite number may be stable. The finite number of stable modes are those corresponding to the longer wavelengths and the growth rates of the infinite number of unstable modes increase as the wavelength decreases. In contrast, the discrete distribution may support only 2N‐3 modes of oscillation. The first modes to become unstable when critical parameters are adjusted are those corresponding to the shortest wavelengths. These also have the highest growth rates. The most significant result of this investigation is that the discrete distribution may have all vibrational modes stable while this is impossible for the continuous distribution. Application of the discrete‐charge theory to explain the stability of experimentally observed vortex patterns in unneutralized electron beams is also discussed.

MODELS describing the central nervous control of thermoregulation1,2 are based at present on the discharge characteristics of temperature rate-sensitive neurones in the preoptic (PO) area and the hypothalamus. These neurones are believed to be involved in thermoregulation because they are anatomically located in an area affecting thermoregulatory control3–5 and respond to both local6–8 and peripheral9–11 temperature change. Examination of the temporal distribution of interspike intervals from PO neurones in our experiments suggests that temperature rate-insensitive PO neurones also process thermoregulatory information.

Sulfamethazine was administered to 8- to 10-week-old turkey poults intravenously (IV) at the dose level of 71.5 mg/kg of body weight, orally at the dose level of 143 mg/kg of body weight, or in the drinking water at the concentration of 0.1% over a 6-day period. The concentrations of free sulfamethazine in blood, muscle, skin, kidney, and liver were determined and semilogarithmic plots of concentration vs time for the various tissues indicated that the curve had a linear portion within the first 72-hour period of drug withdrawal. The rates of disappearance of sulfamethazine from the various tissues were proportional to the concentration in the tissues. After 72 hours of withdrawal and for as long as 14 days, sulfamethazine concentrations in kidney, liver, and skin of turkeys given the drug in the drinking water fluctuated between 0.1 and 0.4 ppm. Only 8.6% of the oral dose (143 mg/kg) and 16.5 to 17% of the IV dose (71.5 mg/kg) were recovered in urine and feces as the parent compound during the initial 72-hour period.

Recent investigations of physiological systems have demonstrated that even minor chemical constituents can play a major role in mediating physiological responses. Recognizing this, the investigator seeks to isolate or selectively quantify the concentration of a specific drug or hormone that is available to target tissue. Today, as drugs are developed which are more and more potent, greater demands are made on analytical methodology for ever more sensitive yet specific techniques of quanification. The techniques of vapor phase analysis such as gas chromatography, especially in combination with mass spectrometry, offer great promise to investigative pharmacology/toxicology. Some of the potentials and limitations of vapor phase analysis will be described. More detailed descriptions of basic gas chromatography (McNair and Bonelli, 1969; Ettre and McFadden, 1969) and combined gas chromatography-mass spectrometry (McFadden, 1973) can be found elsewhere.

Processes to remove jet fuel components harmful to fuel cell performance were tested in simulated and actual cyclic operation using improved molecular sieves. Improved aromatic absorption performance on the lithium X sieve was achieved by pretreating the sieve with high water loading at elevated temperatures. The adsorption performance of processes using displacing agents, as opposed to burning, for desorption was simulated by preloading sieves with displacing agents. An investigation was also made of the feasibility of reforming high molecular weight fuels in the liquid phase for hydrogen generation for fuel cells. The effects of temperature, pressure, hydrocarbon and water feed rates, hydrocarbon drop size and catalyst geometry on the performance of a fixed bed liquid phase reforming reactor were examined. Good selectivity for hydrogen production has been achieved at low hydrocarbon conversion levels. Preliminary data on the use of palladium diffusers to separate the hydrogen product directly from the condensed phase stream leaving the reforming reactor show substantially lower hydrogen extraction rates are obtained from the liquid phase reformer effluent compared with diffusion from a clean hydrogen stream.

Manduca sexta can behaviourally regulate its temperature, but the temperature level is not determined by a simple thermal set-point. Thermoregulation is not localized in a cephalic nervous centre. Both of these characteristics distinguish thermoregulation in M. sexta from thermoregulation as seen in vertebrates. Sustained high temperature is a requisite for flight activity, but regulation of internal temperature is a secondary feature in M. sexta subserving efficient tuning of the flight system.