Information Optimization in Coupled Audio-Visual Cortical Maps

Barn owls hunt in the dark by using cues from both sight and sound to locate their prey. This task is facilitated by topographic maps of the external space formed by neurons (e.g., in the optic tectum) that respond to visual or aural signals from a specific direction. Plasticity of these maps has been studied in owls forced to wear prismatic spectacles that shift their visual field. Adaptive behavior in young owls is accompanied by a compensating shift in the response of (mapped) neurons to auditory signals. We model the receptive fields of such neurons by linear filters that sample correlated audio-visual signals, and search for filters that maximize the gathered information, while subject to the costs of rewiring neurons. Assuming a higher fidelity of visual information, we find that the corresponding receptive fields are robust and unchanged by artificial shifts. The shape of the aural receptive field, however, is controlled by correlations between sight and sound. In response to prismatic glasses, the aural receptive fields shift in the compensating direction, although their shape is modified due to the costs of rewiring.Comment: 7 pages, 1 figur

Gravitationally lensed radio emission associated with SMM J16359+6612, a multiply imaged submillimeter galaxy behind A2218

We report the detection of discrete, lensed radio emission from the multiply imaged, z=2.516 submillimetre selected galaxy, SMM J16359+6612. All three images are detected in deep WSRT 1.4 GHz and VLA 8.2 GHz observations, and the radio positions are coincident with previous sub-mm SCUBA observations of this system. This is the widest separation lens system to be detected in the radio so far, and the first time that multiply imaged lensed radio emission has been detected from a star forming galaxy -- all previous multiply-lensed radio systems being associated with radio-loud AGN. Taking into account the total magnification of ~45, the WSRT 1.4 GHz observations suggest a star formation rate of 500 Solar mass/yr. The source has a steep radio spectrum (alpha -0.7) and an intrinsic flux density of just 3 microJy at 8.2 GHz. Three other SCUBA sources in the field are also detected by the WSRT, including SMMJ16359+66118, a singly imaged (and magnified) arclet at z=1.034. Higher resolution radio observations of SMMJ16359+6612 (and other highly magnified star forming galaxies) provide a unique opportunity to study the general properties and radio morphology of intrinsically faint, distant and obscured star forming galaxies. They can also help to constrain the technical specification of next generation radio telescopes, such as the Square Kilometre Array.Comment: 5 pages, 2 figures, to appear in A&A letter

The lost sunspot cycle: New support from Be10 measurements

It has been suggested that the deficit in the number of spots on the surface of the Sun between 1790 and 1830, known as the Dalton minimum, contained an extra cycle that was not identified in the original sunspot record by Wolf. Though this cycle would be shorter and weaker than the average solar cycle, it would shift the magnetic parity of the solar magnetic field of the earlier cycles. This extra cycle is sometimes referred to as the 'lost solar cycle' or 'cycle 4b'. Here we reanalyse Be10 measurements with annual resolution from the NGRIP ice core in Greenland in order to investigate if the hypothesis regarding a lost sunspot cycle is supported by these measurements. Specifically, we make use of the fact that the Galactic cosmic rays, responsible for forming Be10 in the Earth's atmosphere, are affected differently by the open solar magnetic field during even and odd solar cycles. This fact enables us to evaluate if the numbering of cycles earlier than cycle 5 is correct. For the evaluation, we use Bayesian analysis, which reveals that the lost sunspot cycle hypothesis is likely to be correct. We also discuss if this cycle 4b is a real cycle, or a phase catastrophe, and what implications this has for our understanding of stellar activity cycles in general.Comment: accepted for publication in A&

A survey of the state of teacher effectiveness in four South Jersey high schools

The purpose of this study was to investigate teachers\u27 subjective perception of their teaching effectiveness and the factors that facilitate and/or inhibit their sense of efficacy in four South Jersey high schools. In addition, two problems were examined as to the impact of class size on teaching efficacy and does experience in teaching affect a teacher\u27s sense of effectiveness? The sample was selected from high school teachers in a two county area in southern New Jersey. Teachers were given a questionnaire to complete which was designed to identify important attitudes toward teaching efficacy. A total of 275 questionnaires were distributed and 136 were returned. Data were reported in means, modes, and frequencies for teacher effectiveness; and inferential statistics for comparing the efficacy of experienced versus new teachers. Findings confirmed that teachers in the area are confident in their ability to teach. Two concerns surfaced that reflected a problem: class size and adequate teacher training. The most positive responses were a teacher\u27s ability to adapt to curricular changes, the ability to re-adjust an assignment to a student\u27s level of difficulty, and the ability to redirect a noisy student. There were no statistical differences between experienced and new teachers and their attitudes toward efficacy

The relationship of locus of control, self-esteem, and level of social play

The purpose of this study was to determine whether there was a relationship among children\u27s internal or external locus of control, self-esteem, and level of social play. The study, conducted early in the year to minimize the effect of the classroom environment on test results, included 39 children enrolled in either the morning or afternoon sections of the author\u27s kindergarten class. Eight days after the start of school the following instruments were administered individually to each child by trained volunteers: the Preschool and Primary Nowicki-Strickland Internal-External Control Scale (PPNS-IE) by Stephen Nowicki, Jr., and Marshall P. Duke to assess locus of control and the Preschool Self-Concept Picture Test (PSCPT) by Rosestelle B. Woolner to assess self-esteem. After school was in session for 10 days, trained volunteers observed and coded children\u27s play behavior on a rating scale in which values were assigned to the following behavior categories: unoccupied behavior, solitary play, onlooker behavior, parallel play, associative play, and cooperative play. In addition, a scale reflecting negative, positive, and neutral affect was used. The schedule for coding was arranged so that each child was observed twice during a 60 minute play period on 4 different days over a 2 week interval. The variables in this study included self-esteem, locus of control, play category, affective category, age in years, and sex of child. The relationship among the variables was assessed in two ways, correlational analysis and analyses of variance. Results of this study indicated that there were no significant relationships among locus of control, self-esteem, and level of social play. However, correlations were found between play category and age, play category and affective category, and sex of child and self-esteem. A two-way analysis of variance using self-esteem scores, with sex of child and age group as factors, revealed that age group was highly significant and sex of child by age group interaction was also significant. The ANOVA of the play category scores, with sex of child and age group as factors, revealed that age group was nearly significant. In the analysis of self-esteem scores, with sex of child and locus of control group as factors, sex of child was significant

Policy instruments in the Common Agricultural Policy

Policy changes in the Common Agricultural Policy (CAP) can be explained in terms of the exhaustion and long-term contradictions of policy instruments. Changes in policy instruments have reoriented the policy without any change in formal Treaty goals. The social and economic efficacy of instruments in terms of evidence-based policy analysis was a key factor in whether they were delegitimized. The original policy instruments were generally dysfunctional, but reframing the policy in terms of a multifunctionality paradigm permitted the development of more efficacious instruments. A dynamic interaction takes place between the instruments and policy informed by the predominant discourses