RESUMEN
We report on the first timescale based entirely on optical technology. Existing timescales, including those incorporating optical frequency standards, rely exclusively on microwave local oscillators owing to the lack of an optical oscillator with the required frequency predictability and stability for reliable steering. We combine a cryogenic silicon cavity exhibiting improved long-term stability and an accurate ^{87}Sr lattice clock to form a timescale that outperforms them all. Our timescale accumulates an estimated time error of only 48±94 ps over 34 days of operation. Our analysis indicates that this timescale is capable of reaching a stability below 1×10^{-17} after a few months of averaging, making timekeeping at the 10^{-18} level a realistic prospect.
RESUMEN
It has been estimated that between 3% and 7% of children suffer from attention deficit hyperactivity disorder (ADHD). It is probable, therefore, that these children will present in any dental office. ADHD is characterized by inattention, overactivity and impulsivity. Such symptoms can be quite severe and often present challenges in the dental setting. ADHD symptoms are often managed by medication; and it is important for the clinician to be familiar with these medications to determine when to schedule dental appointments. In dealing with ADHD children, adjunctive behavioral strategies are often useful. Several basic techniques are discussed here.
Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Conducta Infantil , Atención Odontológica/psicología , Relaciones Dentista-Paciente , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/uso terapéutico , Niño , Humanos , Padres , Relaciones Profesional-Familia , Refuerzo en PsicologíaRESUMEN
ADHD is a common disorder that affects individuals of all ages. A thorough evaluation is necessary to make an accurate diagnosis. Symptoms of the disorder can be managed by pharmacological and psychosocial interventions. Due to the high baserate of the disorder as well as its chronic nature, ADHD patients are likely seen frequently in any dental practice. Accordingly, it is necessary for the clinician to be familiar with the disorder as well as with strategies for managing it.