Hybridly-pumped continuous-wave optical parametric oscillator.

We present the first to our knowledge continuous-wave singly-resonant optical parametric oscillator (SROPO) generating tunable signal and idler waves with less than 100 mW single-frequency pump power. This low threshold is achieved by an additional intracavity gain medium that is pumped incoherently. The idler power with respect to the single-frequency pump power shows a bistable behavior which depends strongly on the pumping of the additional amplifier. Furthermore, we demonstrate that such a setup allows a SROPO to be completely diode pumped.

Home environment and adaptive social behavior among premature, low birth weight children: alternative models of environmental action.

Used data from 465 premature, low birth weight children representing three major sociocultural groups (Caucasian, African American, Hispanic) to examine the relation between children's home environments and their adaptive social behavior. Results showed low to moderate associations between scores on the HOME Inventory at 1 and 3 years and scores on two measures of adaptive social behavior at 30 to 36 months, the Adaptive Social Behavior Inventory, and observations of mother-child interaction in a structured laboratory situation. Results indicated that responsive, nurturant care at both 1 and 3 years are related to child adaptive social behavior, as are cognitively stimulating experiences and materials. However, canonical correlational analysis indicated that only Acceptance and Variety of Experience, measured at age 3, and Variety of Experience measured at age 1 accounted for independent amounts of variance in adaptive social behavior as perceived by mothers. Also, only sociocultural group status and Learning Materials at 36 months contributed to the prediction of persistence and enthusiasm as observed in the laboratory setting.

Medical students' understanding of ethical issues in the ambulatory setting.

BACKGROUND: The education of medical students concerning ethical issues focuses mainly on critically ill hospitalized patients. However, in the outpatient setting physicians encounter many problems that require ethical decision making. The present study is an assessment of medical students' awareness and understanding of ethical issues commonly encountered in the ambulatory setting. METHODS: A questionnaire was designed to evaluate general knowledge of medical ethics using 12 clinical vignettes. These vignettes depict situations in the ambulatory setting which involve ethical problems. The questionnaire was distributed to medical students who were asked to state whether an ethical issue was present, its significance, and what the specific issue was. RESULTS: Students' abilities to identify that an ethical issue was involved in each vignette ranged from 34.2% to 96.4%. A majority of students identified the presence of an ethical dilemma in seven out of 12 vignettes. The significance rating varied from 2.8 to 4.4 on a scale of 1 to 5. The results indicate that traditional education in medical ethics does not necessarily prepare students to recognize these problems in the clinical setting. CONCLUSIONS: The medical students surveyed for this study seem to be variably prepared to recognize obvious ethical dilemmas in the ambulatory setting. Medical education must prepare students to recognize and appropriately manage these commonly encountered situations.

Remembering and constructing an order.

The purpose of this study was to determine whether children who could recognize a linear order would be able to use this recognition to answer new questions about the linear order. Three-, 4-, 5-, and 6-year-old children were trained to choose a series over a nonseries, a series over a series ordered in the opposite direction, or one nonseries over another nonseries. They were also given a standard seriation task. Children could recognize a series before being able to construct one, but recognition of a series was not correlated with construction of a series. Although children did not use the linear order to construct a series, they could use it to make choices between two similar stimuli, only one of which contained a feature identical to the linear order. The comparison between seriation and recognition of one nonseries over another revealed that performance on these two tasks was correlated and that one common feature between them was systematicity, which occurred either in searching for relationships or constructing them.