Angular distribution of neutrons from deuterated cluster explosions driven by femtosecond laser pulses.

We have studied experimentally the angular distributions of fusion neutrons from plasmas of multi-keV ion temperature, created by 40 fs, multi-TW laser pulses in dense plumes of D2 and CD4 clusters. A slight anisotropy in the neutron emission is observed. We attribute this anisotropy to the fact that the differential cross section for DD fusion is anisotropic even at low collision energies, and this, coupled with the geometry of the gas jet target, leads to beam-target neutrons that are slightly directed. The qualitative features of this anisotropy are confirmed by Monte Carlo simulations.

The primal scene and Picasso's Guernica.

The author examines a group of works by Picasso dating from the late 1930s in terms of the artist's experiences as documented by his biographers and of primal-scene fantasies as described in the field of psychoanalysis by, in particular, Freud and Klein. Pointing out that the artist himself is on record as inviting such a consideration, he contends that these fantasies constitute the latent motivating force behind one of Picasso's most famous paintings, the mural Guernica, and a number of other productions from the same period. Biographical accounts are drawn upon to show how aspects of his inner world are revealed in the specific works described and reproduced in this paper. The role of women is shown to have been particularly relevant. The author demonstrates how Picasso's constant pattern of triangular relationships culminated in his personal crisis of 1935, which, together with the Spanish Civil War, reflecting as it did the conflicts of his internal and external relations, contributed to the production of the works in this group. The artist is seen as attempting to work through and make reparation for envious attacks on the parental objects, but it is pointed out that art works should not be assessed by the criterion of therapeutic change.

Older adults and assistive devices: use, multiple-device use, and need.

Responses of older adults ( greater than 65 years) from the 1990 National Health Interview Survey and Assistive Device Supplement are analyzed to determine if selected demographic and health variables are associated with the use of assistive devices, multiple-device use, and the expressed need for such devices. Bivariate and multi-variate analyses show that, in general, poorer health is consistently associated with the use of assistive devices, multiple-device use, and expressed need. Demographic characteristics, however, vary in their relationships to assistive device use and need. Findings support the importance of considering multiple-device use and expressed need in studying assistive devices and older adults.

Unstable angina: relationship of clinical presentation, coronary artery pathology, and clinical outcome.

Patients with unstable angina are heterogeneous with respect to presentation, coronary artery morphology, and clinical outcome. Subclassification of these patients based on clinical history has been proposed as a means of identifying individuals at increased cardiac risk. We applied such a classification system to 129 patients discharged from a coronary care unit with a diagnosis of acute myocardial ischemia. Patients were then assessed for cardiac events (recurrent angina requiring revascularization, myocardial infarction, death) 12 months following hospital discharge. Patients were classified as recent onset unstable angina preinfarction (n = 42), crescendo unstable angina preinfarction (n = 48), and unstable angina postinfarction (n = 39). Within each of these groups, the patients were further subclassified based on the occurrence of angina on effort, at rest, or both. No attempt was made to subset patients taking anti-ischemic drugs at the time of clinical presentation to the physician. Coronary angiographic pathology (morphology and number of vessels involved) was similar in the subgroups, but coronary artery thrombus was statistically more likely to be found in patients with crescendo rest angina preinfarction or with frequent anginal episodes at rest postinfarction. Mortality was significantly higher for patients with unstable angina postinfarction (7.7%) than preinfarction (1.1%). No statistical differences were noted between the subgroups with respect to the occurrence of myocardial infarction or recurrent unstable angina requiring revascularization. These data suggest that subclassification of unstable angina patients based on clinical characteristics at presentation is not useful to predict subsequent myocardial infarction or recurrent angina requiring revascularization.(ABSTRACT TRUNCATED AT 250 WORDS)

External stabilization of flail chest using continuous negative extrathoracic pressure.

On rare occasions after total sternectomy, patients develop persistent flail chest deformities requiring long-term mechanical respiratory assistance. We report the use of a temporary external chest shell to deliver constant negative extrathoracic pressure (CNEP) to a long-term ventilated patient with flail chest. The patient's anterior thoracic cage stabilized, and significant improvement in pulmonary function was observed. With these data in hand, an operation was done to permanently stabilize the anterior chest wall by bone grafting.

Midazolam-associated alterations in cardiorespiratory function during colonoscopy.

Twenty patients undergoing clinically indicated elective colonoscopy were prospectively monitored noninvasively for alterations in cardiorespiratory function. Most of the patients were elderly and many had either cardiac or pulmonary disease. All subjects were premedicated with intramuscular meperidine and continuously monitored with ECG, blood pressure, earlobe pulse oximetry, nasal air flow by thermistor probe, and impedance pneumography. Any use of additional analgesic or sedative was determined by the endoscopist, who was blinded to the physiologic tracings, and dosages of medications given were titrated to each patient's tolerance of the procedures as assessed by the endoscopist. Seventeen patients (85%) required additional sedation with the benzodiazepine, midazolam. These patients exhibited frequent episodes of hypotension (reductions in mean arterial blood pressure of 23 +/- 12 mm Hg from baseline, means +/- SD) and respiratory depression (as noted by the greater number of apneas and arterial oxygen desaturation as low as 7.1 +/- 2% from baseline, means +/- SD). In addition, elderly patients and patients with an underlying history of cardiac or pulmonary disease had a greater incidence of potentially untoward cardiorespiratory events.