Training to test interval as a determinant of a temporally graded ECS-produced response decrement in rats.

To identify determinants of HIV seroconversion among injection drug users (IDUs) during a period of rising prevalence, a case-control investigation was conducted. Cases were IDUs with a new positive test after 1 January 1994, and a negative test within the prior 18 months. Controls required 2 negative tests during the same period. Subjects completed a questionnaire on demographic, psychosocial, and behavioural factors. Eighty-nine cases and 192 controls were similar with respect to gender, age, ethnicity and inter-test interval. Multivariate analyses of events during the inter-test interval showed borrowing syringes (adj. OR=2.96; P 0.006), unstable housing (adj. OR=2.01; P =0.03) and injecting 4 times daily (adj. OR=1.71; P =0.06) to be independently associated with seroconversion. Protective associations were demonstrated for sex with opposite gender (adj. OR=0.36; P =0.001) and tetrahydrocannabinol use (adj. OR=0.41; P =0.001). There is a need to evaluate programmes dealing with addiction, housing and the social underpinnings of risk behaviours in this population. <

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RESPONSE PROPERTIES OF INTERNEURONS OF THE CRICKET CERCAL SENSORY SYSTEM ARE CONSERVED IN SPITE OF CHANGES IN PERIPHERAL RECEPTORS DURING MATURATION

Journal of Experimental Biology ◽

10.1242/jeb.164.1.205 ◽

1992 ◽

Vol 164 (1) ◽

pp. 205-226 ◽

Cited By ~ 1

Author(s):

AKIRA CHIBA ◽

GÜNTER KÄMPER ◽

R. K. MURPHEY

Keyword(s):

Sensory Neurons ◽

Sensory System ◽

Postembryonic Development ◽

Response Decrement ◽

Response Properties ◽

Hair Sensilla ◽

Intensity Response ◽

The Central Nervous System ◽

Constant Output ◽

Rate Of Response

During postembryonic development of the cricket, the total number of filiform hair sensilla in the cereal sensory system increases approximately 40-fold. In addition, individual receptor hairs grow in size, changing the transducer properties of the sensilla and, thereby, the information transmitted to the central nervous system (CNS) by the sensory neurons. Interneurons MGI and 10–3 receive monosynaptic inputs from these sensory neurons and send outputs to anterior ganglia. We show that, in spite of the changes in the periphery, the response properties of these interneurons are relatively constant during development. The two interneurons differ in their frequency response, intensity response and rate of response decrement. Their respective response properties are conserved during the postembryonic period. The results suggest that systematic rearrangement of the sensory neuron-to-interneuron synapses plays an important role in maintaining a constant output of this sensory system to higher centers of the CNS during maturation of the cricket.

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The Effects of Test Interval on Safety Instrumented Function (SIF) According to Safety Integrity Level (SIL) Value on Three Phase Separator Application

10.2118/176307-ms ◽

2015 ◽

Author(s):

Totok R. Biyanto ◽

Andika D. S. Natawiria ◽

Franky Kusuma ◽

Ali Musyafa ◽

Ronny D. Noriyati ◽

...

Keyword(s):

Test Interval ◽

Safety Integrity Level ◽

Three Phase ◽

Phase Separator

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An Acridid Auditory Interneurone

Journal of Experimental Biology ◽

10.1242/jeb.51.1.247 ◽

1969 ◽

Vol 51 (1) ◽

pp. 247-260

Author(s):

C. H. FRASER ROWELL ◽

J. M. McKAY

Keyword(s):

Complete Recovery ◽

Significant Negative Correlation ◽

Slight Reduction ◽

Central Control ◽

Response Decrement ◽

Descending Inhibition ◽

Response Level ◽

Short Pulses ◽

Prothoracic Ganglion ◽

Central Lesions

1. The alpha neurone habituates to repetitive short (40 msec.) or long (2-3 sec.) pulses of sound. The response decrement to 10 short pulses at 1/sec. is exponential. Twenty-five minutes is required for complete recovery to 20 short pulses at 1/sec. No dishabituation followed various changes in stimulus repetition. 2. The C.N.S. affects both response level and habituation. In 13% of all animals the neurone was completely inhibited by the head ganglia and was disinhibited by decapitation. Progressive lesions reveal strong inhibition by the head ganglia, and possibly weaker inhibition by the abdominal chain; the prothoracic ganglion has no apparent effect. 3. Removal of the head ganglia almost halves the habituation rate; further removal of the abdominal chain may give a further slight reduction; the prothoracic ganglion has no effect. 4. There is a significant negative correlation between response level and habituation. This could be partially explained if the absolute response decrement is independent of response level. The remaining decrease in habituation observed suggests either a further link between response level and habituation at the synapse, or possibly independent central control of both. Central control affects habituation more than response level. 5. Spontaneous variation in response level is unaffected by the various central lesions. It thus arises in the posterior thoracic ganglia, and not as descending inhibition or excitation from higher centres. 6. These findings are related to the animal's biology and to previous work.

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