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Optical metasurfaces are regular quasi-planar nanopatterns that can apply diverse spatial and spectral transformations to light waves. However, metasurfaces are no longer adjustable after fabrication, and a critical challenge is to realise a technique of tuning their optical properties that is both fast and efficient. We experimentally realise an ultrafast tunable metasurface consisting of subwavelength gallium arsenide nanoparticles supporting Mie-type resonances in the near infrared. Using transient reflectance spectroscopy, we demonstrate a picosecond-scale absolute reflectance modulation of up to 0.35 at the magnetic dipole resonance of the metasurfaces and a spectral shift of the resonance by 30 nm, both achieved at unprecedentedly low pump fluences of less than 400 μJ cm-2. Our findings thereby enable a versatile tool for ultrafast and efficient control of light using light.Metasurfaces are not adjustable after fabrication, and a critical challenge is to realise a technique of tuning their optical properties that is both fast and efficient. Here, Shcherbakov et al. realise an ultrafast tunable metasurface with picosecond-scale large absolute reflectance modulation at low pump fluences.

Objective: To examine the test-retest reliability of a new interviewer-based psychiatric diagnostic measure (the Preschool Age Psychiatric Assessment) for use with parents of preschoolers 2 to 5 years old. Method: A total of 1,073 parents of children attending a large pediatric clinic completed the Child Behavior Checklist 1 1/2-5. For 18 months, 193 parents of high scorers and 114 parents of low scorers were interviewed on two occasions on an average of 11 days apart. Results: Estimates of diagnostic reliability were very similar to those obtained from interviews with parents of older children and adults, with kappas ranging from 0.36 to 0.79. Test-retest intraclass correlations for DSM-IV syndrome scale scores ranged from 0.56 to 0.89. There were no significant differences in reliability by age, sex, or race (African American versus non-African American). Conclusions: The Preschool Age Psychiatric Assessment provides a reasonably reliable standardized measure of DSM-IV psychiatric symptoms and disorders in preschoolers for use in both research and clinical service evaluations of preschoolers as young as 2 years old. (Contains 1 figure and 5 tables.)

A micromachined accelerometer device structure with diffraction-based optical detection and integrated electrostatic actuation is introduced. The sensor consists of a bulk silicon proof mass electrode that moves vertically with respect to a rigid diffraction grating backplate electrode to provide interferometric detection resolution of the proof-mass displacement when illuminated with coherent light. The sensor architecture includes a monolithically integrated electrostatic actuation port that enables the application of precisely controlled broadband forces to the proof mass while the displacement is simultaneously and independently measured optically. This enables several useful features such as dynamic self-characterization and a variety of force-feedback modalities, including alteration of device dynamics in situ. These features are experimentally demonstrated with sensors that have been optoelectronically integrated into sub-cubic-millimeter volumes using an entirely surface-normal, rigid, and robust embodiment incorporating vertical cavity surface emitting lasers and integrated photodetector arrays. In addition to small form factor and high acceleration resolution, the ability to self-characterize and alter device dynamics in situ may be advantageous. This allows periodic calibration and in situ matching of sensor dynamics among an array of accelerometers or seismometers configured in a network. [2007-0122] Index Terms--Acceleration measurement, diffraction, feedback system, optical interferometry.

Poverty may be a direct cause of some types of mental illness, according to a study of 1,420 children in western North Carolina before and after a casino opened on an Indian reservation. The families of some of the Indian children in the study began receiving income from the casino, which moved 14% of the families out of poverty. The children in these families had fewer psychiatric symptoms after the casino opened than they did before it opened.

Objectives. To identify age-related trajectories of obesity from childhood into adolescence, and to test the association of these trajectories with the development of psychiatric disorders (conduct disorder, oppositional defiant disorder, attention-deficit/hyperactivity disorder, substance abuse, depression, and anxiety). Methods. White children (N = 991) 9 to 16 years old from the Great Smoky Mountains Study, a representative sample of rural youth, were evaluated annually over an 8-year period for height, weight, psychiatric disorder, and vulnerabilities for psychiatric disorder. Longitudinal analyses on the repeated measures data were conducted using developmental trajectory models and generalized estimating equation models. Results. Obesity was 3 to 4 times more common than expected from national rates using Centers for Disease Control And Prevention 2000 criteria. Four developmental trajectories of obesity were found: no obesity (73%), chronic obesity (15%), childhood obesity (5%), and adolescent obesity (7%). Only chronic obesity was associated with psychiatric disorder: oppositional defiant disorder in boys and girls and depressive disorders in boys. Conclusions. In a general population sample studied longitudinally, chronic obesity was associated with psychopathology. Pediatrics 2003;111:851-859; obesity, psychopathology, developmental trajectories, depression, conduct disorder., ABBREVIATIONS. GSMS, Great Smoky Mountains Study; BMI, body mass index; NHANES, National Health Interview Survey; CAPA, Child and Adolescent Psychiatric Assessment; ADHD, attention-deficit/hyperactivity disorder; SPMM, semiparametric mixture model; GEE, Generalized [...]

This article discusses the prevalence and psychosocial effects of attention deficit hyperactivity disorder and oppositional defiant disorder in youth. An analysis of social interaction, interpersonal relations, academic achievement, and family relations is presented.

Directional coronary atherectomy may cause more complications than coronary angioplasty in patients with coronary artery disease. Atherectomy is a procedure that involves the direct removal of lipid-containing plaques from the inside of the coronary artery. Angioplasty is a procedure that uses a balloon catheter to flatten plaques against an artery wall. Among 1,012 patients with coronary artery disease, 512 had atherectomy and 500 had angioplasty. Eighty-nine percent of the patients who had atherectomy had a 50% or more reduction in the narrowing of their arteries, compared with 80% of those who had angioplasty. Eleven percent of the patients in the atherectomy group developed early complications, compared with 5% of those in the angioplasty group. The risk of a heart attack or death six months after treatment was higher for patients who had a atherectomy. In-hospital costs were also higher for the patients in the atherectomy group.