Surface salinity fields in the Arctic Ocean and statistical approaches to predicting anomalies and patterns

Significant salinity anomalies have been observed in the Arctic Ocean surface layer during the last decade. Using gridded data of winter salinity in the upper 50 m layer of the Arctic Ocean for the period 1950-1993 and 2007-2012, we investigated the inter-annual variability of the salinity fields, attempted to identify patterns and anomalies, and developed a statistical model for the prediction of surface layer salinity. The statistical model is based on linear regression equations linking the principal components with environmental factors, such as atmospheric circulation, river runoff, ice processes, and water exchange with neighboring oceans. Using this model, we obtained prognostic fields of the surface layer salinity for the winter period 2013-2014. The prognostic fields demonstrated the same tendencies of surface layer freshening that were observed previously. A phase portrait analysis involving the first two principal components exhibits a dramatic shift in behavior of the 2007-2012 data in comparison to earlier observations

Nuclear burst plasma injection into the magnetosphere and resulting spacecraft charging

The passage of debris from a high altitude ( 400 km) nuclear burst over the ionospheric plasma is found to be capable of exciting large amplitude whistler waves which can act to structure a collisionless shock. This instability will occur in the loss cone exits of the nuclear debris bubble, and the accelerated ambient ions will freestream along the magnetic field lines into the magnetosphere. Using Starfish-like parameters and accounting for plasma diffusion and thermalization of the propagating plasma mass, it is found that synchronous orbit plasma fluxes of high temperature electrons (near 10 keV) will be significantly greater than those encountered during magnetospheric substorms. These fluxes will last for sufficiently long periods of time so as to charge immersed bodies to high potentials and arc discharges to take place

Heterogeneous chemistry related to Antarctic ozone depletion: Reaction of ClONO2 and N2O5 on ice surfaces

Laboratory studies of heterogeneous reactions of possible importance for Antarctic ozone depletion were performed. In particular, the reactions of chlorine nitrate (ClONO2) and dinitrogen pentoxide (N2O5) were investigated on ice and HCl/ice surfaces. These reactions occur on the surfaces of polar stratospheric clouds (PSCs) over Antarctica. One reaction transforms the stable chlorine reservoir species (ClONO2 and HCl) into photochemically active chlorine in the form of HOCl and Cl2. Condensation of HNO3 in the reactions removes odd nitrogen from the stratosphere, a requirement in nearly all models of Antarctic ozone depletion. Other reactions may also be important for Antarctic ozone depletion. Like the reactions of chlorine nitrate, these reactions deplete odd nitrogen through HNO3 condensation. In addition, one reaction converts a stable chlorine reservior species (HCl) into photochemically active chlorine (ClNO2). These reactions were studied with a modified version of a Knudsen cell flow reactor

Teaching the discrimination between fact and opinion in grades four and five

Thesis (Ed.M.)--Boston Universit

Attitudes and reported practice of paediatricians and child psychiatrists regarding the assessment and treatment of ADHD in Ireland

Objectives. This mixed-method national survey has obtained original data on attention deficit hyperactivity disorder (ADHD) attitudes, assessment and treatment regimes reported by paediatricians and child psychiatrists; and has compared their clinics. It has examined the extent of involvement of Irish paediatricians in the management of ADHD. Methods. A questionnaire was designed, based on a review of literature and ADHD guidelines, and piloted by expert clinicians. Universal recruitment was conducted among Child and Adolescent Mental Health Services (CAMHS) consultants (n = 71) and community/general paediatric consultants (n = 72). Quantitative and qualitative data was collected and analysed. Results. There was an overall response rate of 43%. A dedicated ADHD clinic is offered in 79% of CAMHS services, but only in one paediatric service. Participants reported that the assessment of ADHD involves multidisciplinary work and this was only established in CAMHS clinics. Medication is initiated by 82% of child psychiatrists and only 22% of paediatricians. Conclusions. This first national study of ADHD attitudes and practices presents comprehensive data regarding the management of children with ADHD in CAMHS and paediatric settings in Ireland. Paediatricians reported a minor role in managing ADHD. Study limitations are related to subjective reporting rather than case note audit, and a moderate response rate for the paediatricians’ participants

Research and education in management of large- scale technical programs Semiannual progress report

Research and education in management of large scale technical programs - education and integration of interdisciplinary tea