Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.

[Q]: Abstract: Twenty years of published experience with the Workman-Armstrong equation for predicting walking VO2 is reviewed. The equation is reexpressed in currently accepted terminology, and it is shown that the equation serves well as a basic model of normal walking. Employing this model to analyze VO2/step leads to the elaboration of a three-compartment model of the metabolic cost of walking. This three-compartment model provides a rational estimate of the fraction of walking's metabolic cost that powers the actual walking movement. Doubt is expressed that "comfortable speed of walking" is definable in energy terms. It is suggested that the requirements of maintaining balance while walking may determine both the comfortable speed of walking and the curvilinearity of the relationship between ground-speed and freely chosen step frequency of walking.
[A]: Metabolic cost of walking: equation and model.

[Q]: Abstract: The clostridial neurotoxins tetanus and botulinum toxin type A are known to block transmitter release from nerve terminals, probably by interfering with some essential process controlling exocytosis after the entry of Ca2+ ions. Although exocytosis occurs in many secretory cells, these toxins show a high specificity for neurones and the secretory response of cultured bovine adrenal medullary cells is not inhibited by exposure to medium containing tetanus or botulinum toxin type A (although it is by botulinum toxin type D). Here we report that when tetanus toxin and botulinum neurotoxin type A are injected intracellularly into chromaffin cells they strongly inhibit secretion, as revealed by the measurement of cell capacitance. These results indicate that these toxins are normally ineffective in chromaffin cells because they are not bound and internalized, so do not reach their site of action. Furthermore, we have localized the secretion-blocking effects of the toxin to a fragment comprising the light chain covalently linked to part of the heavy chain, suggesting that this part of the molecule contains the active site.
[A]: Intracellularly injected tetanus toxin inhibits exocytosis in bovine adrenal chromaffin cells.

[Q]: Abstract: Both halothane and nitrous oxide can be reduced at the cathode of a polarographic oxygen electrode, causing the electrode current to drift upward and report falsely high oxygen tension. Because transcutaneous oxygen tension is measured by a heated oxygen electrode, there is a potential for significant upward drift of these values. To examine the clinical significance of this drift, the following study was performed. Transcutaneous oxygen tension sensors were calibrated at oxygen tensions of 0 mm Hg and 157 mm Hg (room air) just before clinical use during anesthesia. This calibration was rechecked immediately upon removal of the sensor from the patient at the end of the anesthesia. The predominant anesthetic agent used and the duration of monitoring were noted from the record. Data were collected from 208 patients representing a total of 463.6 hours of anesthesia. The patients were divided into five groups based on anesthetic administered: halothane, enflurane, isoflurane, nitrous oxide-narcotic, and local/regional. The mean zero point recalibration value was 0.4 mm Hg or less for all agents except halothane, for which it was 1.8 +/- 3.2 mm Hg. This halothane drift was significantly greater than that for the other agents (P less than 0.01). Room air recalibration was not significantly different in any of the five groups, varying from 160 +/- 4.9 mm Hg for halothane to 157 +/- 4.9 mm Hg for enflurane. All these drift values are within the manufacturer's specifications. We conclude that the drift of the transcutaneous oxygen tension sensor due to anesthetic agents is not clinically significant. However, caution should be exercised when halothane is used during an extremely long period of anesthesia.
[A]:
Effects of anesthetic agents on the drift of a transcutaneous oxygen tension sensor.