Efficient method for controlling the spatial coherence of a laser.

An efficient method to tune the spatial coherence of a degenerate laser over a broad range with minimum variation in the total output power is presented. It is based on varying the diameter of a spatial filter inside the laser cavity. The number of lasing modes supported by the degenerate laser can be controlled from 1 to 320,000, with less than a 50% change in the total output power. We show that a degenerate laser designed for low spatial coherence can be used as an illumination source for speckle-free microscopy that is nine orders of magnitude brighter than conventional thermal light.

Integration of silicon nanocrystals and erbium ring cavities for a silicon pumped Er:SiO2 laser.

In this work we present a novel two-stage approach to achieve electrically pumped lasing on a CMOS compatible material platform in the telecom region. The proposed design consists of an electrically pumped silicon nanocrystal (Si-nc) light source acting as an optical pump for an Erbium doped silicate (Er:SiO2) lasing cavity. The integrated design, based on concentric disks of Si-nc and Er:SiO2, provides a means of coupling the Si-nc pump signal to the Er ions without requiring overlap of the Er based lasing mode with the Si-nc material. We present an electromagnetic analysis of the pump and lasing modes in the proposed configuration. We also present fabrication and characterization of Si-nc and Er:SiO2 microdisks as components of the integrated design.

Knowledge and attitudes of registered nurses toward perinatal substance abuse.

OBJECTIVE: To explore the knowledge and attitudes of registered nurses employed in perinatal nursing and to determine the relationships between selected demographic variables and registered nurses' knowledge and attitudes toward perinatal substance abuse. DESIGN: Descriptive, using a convenience sample. SETTING: Perinatal units at 10 hospitals on the west coast of Florida. PARTICIPANTS: 392 registered nurses employed on perinatal units. MAIN OUTCOME MEASURE: Identification of knowledge and attitudes of registered nurses toward perinatal substance abuse, using the 34-item adapted Attitudes About Drug Abuse in Pregnancy (AADAP) questionnaire. RESULTS: Knowledge scores for the sample ranged from 6 to 18 (M = 12.14) out of a possible score of 20. Attitude scores ranged from 16 to 56 (M = 35.81) out of a possible range of 14 to 70. Scores at the lower end of the scale indicate punitive, negative attitudes. Significant relationships were found among several demographic variables and knowledge and attitude scores for the total sample. CONCLUSIONS: Registered nurses demonstrated limited knowledge about substance exposure, addiction, and its effects. They also held attitudes that were more punitive and negative than positive or supportive toward women who abused substances during the perinatal period.

Determination of water permeability coefficient and its activation energy for rabbit spermatozoa.

Critical tonicity (tonicity at which 50% of cells swell beyond their maximum volume-to-surface area ratio and lyse) of rabbit spermatozoa was measured as 45.6 mOsm at 22 degrees C. To determine the temperature effect on critical tonicity, cells were equilibrated to 15, 25, and 35 degrees C and critical tonicity was measured as 52.9, 42.2, and 32.4 mOsm, respectively. The time taken for rabbit sperm to achieve lysis at these temperatures was measured by exposing cells for increasing times to distilled water. From these results values for the permeability coefficient of rabbit spermatozoa to water (Lp) and its activation energy (Ea) were calculated. At 25 degrees C, Lp was 0.63 micron/min/atm and was clearly temperature dependent; Ea was 17.8 kcal/mol. Rabbit spermatozoa appear to have a low Lp and high Ea, the opposite of the situation seen with spermatozoa from all other species examined to date which have high Lp and low Ea. Nevertheless, the values obtained permit modeling of cooling rates for cell survival during cryopreservation in keeping with cooling rates commonly employed.

Perinatal substance abuse: assessment and management of the pregnant woman and her children.

The use and abuse of alcohol and other drugs by women during the childbearing years continues to be an area of concern. Knowledge of the effects of drugs on the developing fetus and the child postnatally is essential for the NP. This report presents information on the assessment and screening of the pregnant woman who abuses substances. Interventions for mothers and children affected by perinatal substance abuse are also offered.

Evaluating clinical skills of RN students.

A clinical performance examination was developed for basic baccalaureate nursing students and used to validate the clinical skills of registered nurses entering a baccalaureate degree program. With few exceptions, RNs returning to school demonstrated clinical competence in the secondary care area as measured by this examination. Therefore, another means of validating RN clinical skills was developed based on the evaluation criteria used for the clinical performance examination. Using employer and colleague validation, students individually documented competence in the area of practice. There was a decrease in student stress, an increase in self-esteem, conservation of the time and energy of students and faculty, and more effective use of program resources.

A survey of nursing care for parents and infants with cleft lip and palate.

This survey of the hospital nurse's role in patient care when a child is born with an orofacial cleft included nursing assistance offered new parents, identification of specialists for habilitation of the child, and inservice nursing education programs. Findings from 52 hospitals indicated that adequate assistance and information concerning special services for parents and child were not available. Some hospitals offered inservice nursing education in care of parents and children with facial clefts. Suggestions are made concerning nursing education programs in cleft lip and palate.