Effects Of Rate Changes Research Articles

Rate-change effects during a pre-schedule-change stimulus.

Rate-change effects during a pre-schedule-change stimulus.

Credit Availability, Interest Rates, and Monetary Policy

One important strand of the new theory of monetary control (sometimes called the doctrine) is the argument that the effectiveness of monetary policy does not depend solely on changes in interest rates and the impact of rate changes on the demand for loanable funds. Changes in the availability of credit, it is alleged, can reinforce the effects of changes in the rate of interest. This theory has been criticized on the grounds that changes in availability, if they occur, are bound to be temporary and are therefore of no great consequence in stemming (or stimulating) the demand for loanable funds. A further possibility-one curiously neglected by the critics of the availability doctrine, although it appears to have been much in the minds of earlier writers on credit rationing-is that changes in credit availability might be in a direction to offset rather than to reinforce the effects of changes in interest rates.

Renal regulation of urea excretion in sheep.

In order to elucidate the renal mechanism for the regulation of urea excretion the urea clearance and the GFR were studied in sheep during normal and low protein intake in a range of urine flows from extreme osmotic diuresis to minimal flows. Differences in the effects of osmotic and water diureses and the effects of abrupt changes in rate of urine flow were also studied. In sheep on normal protein intake the urea/inulin clearance ratio was constant in the range of urine flows corresponding to inulin U/P ratios from 10 to 500. On low protein intake the urea/inulin clearance ratio decreased markedly with decreasing urine flow. At extremely high urine flows no difference was found between the urea/inulin clearance ratios on different diets. Regulation was found to be independent of GFR, plasma urea concentration and osmotic load and must therefore be on the tubular level. Observations during abrupt changes in urine flow showed that the urea clearance is not only abnormally high during increasing flows but also abnormally low during a sudden decrease in flow. The first phenomenon is known as ‘exaltation,’ and we have termed the latter phenomenon ‘abatement.’ The data on exaltation and abatement and on the effects of urine flow are consistent with a previously suggested hypothesis that the excretion of urea in the mammalian kidney is brought about through a regulated active transport of urea, accentuated by a countercurrent multiplier system represented by Henle's loops and vasa recta.

The ventricular gradient in space

1. 1. A simple, geometric method of determining the spherical coordinates of the ventricular gradient is presented. 2. 2. Electrocardiograms of eight normal subjects are thus analyzed, using the cube method of electrode placement. Mean magnitude, azimuth and elevation are found to be 47 microvolt-seconds, 16 ° and 52 °, respectively. 3. 3. The theory of the gradient is discussed. 4. 4. The role of the RS-T segment is elucidated and a method of evaluating its significance is suggested. 5. 5. Gradients are imposed on hypothetic muscle strips by means of a suitable equation, and the effects of change in rate and direction of activation on the form and area of the ventricular complex are demonstrated. It is concluded that these do not influence net area. 6. 6. A block diagram of an instrument for instantaneous determination of the gradient is included.

Influence of temperature and rate on the contractility of isolated turtle myocardium.

The effects of changes in rate of stimulation on contractile force of turtle myocardium were studied at various temperatures. At 38°C an increase in rate produced an increase in the contractile force (positive treppe). At 14°C increasing the rate produced a decrease in the contractile force (negative treppe). At intermediate temperatures an increase in rate produced first a positive followed by a negative treppe. Under anaerobic conditions the results were qualitatively the same although contractility was reduced by 50–75%. The increase in contractile force seen after an episode of rapid stimulation (poststimulation contraction) was studied at different temperatures. An increase in the rapid stimulation rate produced an increase in poststimulation potentiation at all temperatures studied except at 14°C where an increase in rate produced a decrease in potentiation. Some of these results can be explained on the basis of energy production which is probably depressed at low temperatures. On the other hand some other factor related to rate of stimulation must influence contractile force. This factor may be related to the active state of A. V. Hill or may be related to ionic movements postulated by Hajdu and Szent-Gyorgyi.

Effect of Heart Rate on Cardiac Membrane Potentials and the Unipolar Electrogram

Effect of Heart Rate on Cardiac Membrane Potentials and the Unipolar Electrogram

Notes on the Effect of Changes in Rates of Interest on the Bonus-Earning Power of an Office Paying a Uniform Compound Reversionary Bonus

SynopsisThe Paper discusses the general problem of appreciation and depreciation, with special reference to the relation between maturing assets and maturing liabilities, and describes a method of calculating the bonus-earning power of different classes of policy. This method is used to test the effect on bonus-earning power of two types of changes in interest rates:–(a)a change, such as that caused by the War Loan conversion of 1932, which takes effect gradually; and(b)a subsequent change, due to a rise in the rate of income tax, which has an immediate effect on the income from existing as well as investments.