Status of the Lawrence Berkeley Laboratory and Lawrence Livermore National Laboratory free electron laser (FEL)

A description of the FEL experiment underway at the 10 kA, 5 MeV Experimental Test Accelerator (ETA) is described. The facility has been designed to investigate the high-gain operation of an FEL

MBE-4, a heavy ion multiple-beam experiment

MBE-4, a heavy-ion multiple beam induction linac being built at LBL in FY85/86, will model many features of a much longer device. It will accelerate four space-charge-dominated cesium ion beams from, for example, 0.2 MeV, 5 mA/beam, 3.0 ..mu..sec, 1.6 m length at injection to approx.0.8 MeV, 15 mA/beam, 1.0 ..mu..sec, 1.1 m length at the exit. It will permit study of simultaneous focussing, acceleration, current amplification and emittance growth of multiple space-charge-dominated ion beams. Some features of this accelerator are described. 11 refs., 5 figs

The Protective Effects of Sense of Community, Multigroup Ethnic Identity, and Self-Esteem Against Internalizing Problems Among Dominican Youth: Implications for Social Workers

This study examined the risk and protective factors associated with internalizing problems among Dominican adolescents (N = 500; 58% female) attending high school (grades 9-12) in a Northeastern, high poverty, urban community. Using a path analysis, this study found that depression and anxiety are complex mental health constructs and there are many factors that contribute to their developmental trajectory. Findings revealed that greater disorganization in one\u27s neighborhood, perception of availability of drugs and handguns in one\u27s community, and overall drug use and violent behaviors were linked with depression and anxiety. Conversely, higher levels of sense of community, which was linked to positive multigroup ethnic identity, and higher levels of self-esteem had a protective effect against depression and anxiety. Implications for social workers are discussed