Biomedical subjects

M H Dunn

Publications and source records attributed to M H Dunn.

3 recordsLinked to original sources

PubMed2003

Compact, continuous-wave, singly resonant optical parametric oscillator based on periodically poled RbTiOAsO4 in a Nd:YVO4 laser.

We describe a compact all-solid-state continuous-wave, singly resonant optical parametric oscillator (SRO) based on periodically poled RbTiOAsO4. The SRO is pumped at 1.064 microm by a Nd:YVO4 laser, which is itself pumped by a 3-W diode laser. Using the intracavity technique produced an oscillation threshold for the SRO of only 1.6 W (diode-laser power). For 3 W of diode pump power some 65 mW was obtained in the (nonresonant) idler (wavelength 3.52 microm). Temperature tuning over the range 10-100 degrees C resulted in tuning ranges of 1.52-1.54 and 3.41-3.54 microm for the signal and the idler waves, respectively. Importantly, relaxation oscillations were absent.

Journal Article↗

PubMed1996

Insanity defense pleas in Baltimore City: an analysis of outcome.

OBJECTIVE: The authors studied all defendants in Baltimore City's circuit and district courts who pleaded not criminally responsible, Maryland's version of the not guilty by reason of insanity plea, during a 1-year period. The study was designed to compare the perception that the insanity plea is misused to actual outcome data. METHOD: The cohort of defendants who pleaded not criminally responsible in both the circuit and district courts during calendar year 1991 was identified. Data on demographic characteristics, crimes committed, diagnoses, and psychiatrists' opinions on criminal responsibility were collected. Trial outcome data were obtained through a search of the circuit and district court computer systems. RESULTS: Of the 60,432 indictments filed in the two courts, 190 defendants (0.31 per 100 indictments) entered a plea of not criminally responsible. All but eight defendants (0.013 per 100 indictments) dropped this plea before trial. For these eight cases, both the state and the defense agreed that the defendant should be found not criminally responsible, and the plea was uncontested at trial. The remaining defendants had their charges dropped before trial, remained not competent to stand trial at the time of the study, or withdrew their pleas of not criminally responsible before trial. CONCLUSIONS: There were no trials that contested the plea of not criminally responsible. The state and defense agreed with each other for all of the defendants who actually retained the plea at trial. The perception that the insanity defense is overused and misused is not borne out by data.

Adult↗

PubMed1975

Diurnal fluctuations of testosterone and LH in the ram: effect of HCG and gonadotrophin-releasing hormone.

To examine a possible relationship between the release of LH and increasing testosterone levels, blood samples were collected at 2-hr intervals for 24 hr from six mature rams with indwelling jugular cannulae. Although high levels of LH often preceded increases of testosterone, a consistent time relationship between these two hormones was not observed, nor was a diurnal rhythm established for either hormone. The following day, two rams were each injected intravenously with saline, 500 i.u. HCG, or 100 mug synthetic gonadotrophin-releasing hormone (Gn-RH) respectively. Immediately after the injection, blood was collected every 15 min for approximately 4 hr. After Gn-RH, the plasma LH rose 25- to 50-fold within 12 min and was elevated for more than 3 hr. A twofold rise of plasma testosterone followed this increase of LH and testosterone remained high until the end of the experiment. After HCG treatment, the level of testosterone rose threefold within 30 min and did not decline during the experiment, but there was no effect on the LH level. Saline treatment did not influence levels of LH or testosterone. It was concluded that daily fluctuations of testosterone and LH may occur independently, and no pattern is common to all rams. Treatment with Gn-RH results in a rise in both the testosterone and LH levels, but only testosterone is affected by HCG.

Animals↗