A high-sensitivity drinkometer circuit with 60-Hz filtering

This article describes a drinkometer circuit designed to (1) detect licks even if the resistance of the skin on the animal’s feet becomes quite high due to low humidity, (2) automatically adjust its triggering threshold and increase its gain so that it will continue to detect licks when the water delivery spout is partially shorted to ground by high ambient humidity, (3) reject 60-Hz signals so they will not be treated as rapid licks by the data-recording system, and (4) tolerate the high voltages that can occur if the subject receives an electric shock while drinking. This lickometer will be especially useful in situations where it is not practical to monitor for possible signal failure due to high or low humidity, or where 60-Hz artifacts may contaminate the signal provided to a recording computer.     

An electromechanical analyzer using histogram techniques

In behavioral studies it is often necessary to classify events and store the number of events occurring in each classification. The classification requirements may be either functions of amplitude (i.e., intensity, force, peaks, etc.) or time (i.e., duration, interval, etc.). The following describes an analyzer capable of classifying events according to their duration, interval, or time of occurrence, and storing and displaying the number of such events in each classification.     

A circuit to permit an electronic drinkometer to operate during footshock

A circuit to permit an electronic drinkometer to operate during footshock is described. The circuit employs a diode matrix that allows all grid bars to be connected at one point to form one electrode of the drinkometer; it is isolated at another point so as not to shortcircuit the impressed footshock.     

Interfacing the DEC LPS 11 to electromechanical laboratory apparatus

A hardware-software extension to the DEC LPS 11 facilitates interfacing the PDP 11 to external instruments. The hardware component consists of eight relay drivers and relays, four contact conditioners, and an interrupt pulse former. FORTRAN-callable RT-11 MACRO subroutines control the device, service interrupts, and transfer control to FORTRAN completion routines.     

Piezoelectric and electromechanical coupling constants for GaxIn1-xSb semiconducting alloys

The compositional dependence of piezoelectric stress and strain constants and electromechanical coupling coefficient of Ga_xIn_1-xSb have been investigated. The calculations were performed using a pseudopotential approach combined with the Adachi model where different concepts of ionicity are considered. Our results are compared with the available data and found to be in good accord with each other. Our findings show that as the Ga content varies, the piezoelectric and related constants and transport properties of the alloy system of interest are significantly affected.     

Reaction times and electromechanical delay in reactions of increasing and decreasing force

The purpose of this study was to compare reaction times and electromechanical delay between reactions to increase force from rest and reactions to decrease force from an active state in the quadriceps femoris of healthy young adults. Force, position, and electromyographic data were recorded from 35 subjects reacting to a forced knee-flexion perturbation. Electromechanical delay was assessed through cross-correlation of the filtered EMG and force data. Reaction time to increase force (M= 159.9 msec., 95% CI= 149.9-169.9 msec.) was significantly longer than RT to decrease force (M= 124.4 msec., 95% CI= 118.7-130.1 msec.). This difference was partially caused by a difference in electromechanical delay (RT to increase force electromechanical delay was 63 msec., 95% CI=60-67 msec., greater than the RT to decrease force electromechanical delay of 49 msec., 95% CI=46-52 msec.). This difference in reaction time could be important in identifying and interpreting physiologically meaningful changes in muscle force and in intermuscular coordination during movement.     

Is An Agreement An Exchange of Intentions?

Abstract: Margaret Gilbert has argued that an agreement is not exchange of promises, since no such exchange plays all the roles she claims are distinctive of agreements. After briefly discussing the notion of intention and the principles governing intentions, I argue that a certain type of exchange of intentions – in which one person forms a conditional intention to act if the other does, and the other forms an unconditional intention to act on the presumption that the first will do what they have said – plays all these roles, and so conclude that an agreement is in fact an exchange of intentions.