Horizontal flow fields observed in Hinode G-band images II. Flow fields in the final stages of sunspot decay

We present a subset of multi-wavelengths observations obtained with the Japanese Hinode mission, the Solar Dynamics Observatory (SDO), and the Vacuum Tower Telescope (VTT) at Observatorio del Teide, Tenerife, Spain during the time period from 2010 November 18-23. Horizontal proper motions were derived from G-band and Ca II H images, whereas line-of-sight velocities were extracted from VTT Echelle H-alpha 656.28 nm spectra and Fe I 630.25 nm spectral data of the Hinode/Spectro-Polarimeter, which also provided three-dimensional magnetic field information. The Helioseismic and Magnetic Imager on board SDO provided continuum images and line-of-sight magnetograms as context for the high-resolution observations for the entire disk passage of the active region. We have performed a quantitative study of photospheric and chromospheric flow fields in and around decaying sunspots. In one of the trailing sunspots of active region NOAA 11126, we observed moat flow and moving magnetic features (MMFs), even after its penumbra had decayed. We also noticed a superpenumbral structure around this pore. MMFs follow well-defined, radial paths from the spot all the way to the border of a supergranular cell surrounding the spot. In contrast, flux emergence near the other sunspot prevented it from establishing such well ordered flow patterns, which could even be observed around a tiny pore of just 2 Mm diameter. After the disappearance of the sunspots/pores a coherent patch of abnormal granulation remained at their location, which was characterized by more uniform horizontal proper motions, low divergence values, and diminished photospheric Doppler velocities. This region, thus, differs significantly from granulation and other areas covered by G-band bright points. We conclude that this peculiar flow pattern is a signature of sunspot decay and the dispersal of magnetic flux.Comment: 13 pages, 11 figures, accepted for publication in Astronomy and Astrophysic

Point interaction in dimension two and three as models of small scatterers

In addition to the conventional renormalized--coupling--constant picture, point interactions in dimension two and three are shown to model within a suitable energy range scattering on localized potentials, both attractive and repulsive.Comment: 6 pages, a LaTeX fil

Earth Potential Electrodes in Permafrost and Tundra

Introduction : During the past two years, the authors installed a number of electrodes in the permafrost and tundra area of Point Barrow to obtain earth potential data. As ground temperatures decreased during the winter, the resistances of the first set of electrodes increased by several orders of magnitude and thus became useless. A second set of electrodes, with sodium chloride incorporated in the fill, proved entirely adequate for recording earth potentials. The installations and procedure for determining electrode resistances are described herein. Electrode resistance data versus time and ground temperatures are also presented.Ye

Development of generalized index-removal models, with particular attention to catchability issues

The index-removal method estimates abundance, exploitation and catchability coefficient, given surveys conducted before and after a known removal. The method assumes a closed population between surveys. Index-removal has seldom been applied due to its strong assumption of constant survey catchabilities. This work generalizes the method to allow multiple years of data to be incorporated, and the assumptions of the original model to be relaxed. If catchability is constant across years, precision can be improved by analyzing multi-year data simultaneously. Two multiple-year models were developed: the first, 1qIR, assumes constant catchability within and among years; the second, 2qIR, allows catchability to change between surveys within years, but assumes survey-specific catchability constant across years. The new models were tested by Monte Carlo simulation then applied to data from two southern rock lobster (Jasus edwardsii) populations. The 1qIR model produced reasonable estimates in one application, but the 2qIR model was required to produce reasonable estimates for the second population. A likelihood ratio test found 1qIR to be the most parsimonious model, even when, the assumption of constant survey catchability appeared to be violated. In that case, diagnostic plots suggested that the 2qIR model provided the most reliable estimates. However, when the constant catchability assumption is tenable, the 1qIR model offers the greatest precision for parameter estimates. Size- and sex-specific heterogeneity of catchability introduces bias in model estimates. Field experiments were performed to test whether the catchability of small lobster was constant for southern rock lobster during two seasons when fishing occurs. No evidence of heterogeneous catchability was observed during the spring. However, significantly more small lobster were caught in control traps and traps seeded with one large adult male lobster than were caught in traps seeded with one large adult female during the summer, when females are preparing to molt and reproduce in Tasmania. Because heterogeneous catchability occurred during the summer, but not the spring, an index of recruitment based on the catch of lobsters one molt size below legal size might be developed for the spring, however, more sampling is needed to resolve the annual timing of sex- and size-specific catchability changes

ATTITUDES OF STAKEHOLDERS TOWARD THE INCLUSION AND TEACHING OF SEXUALITY EDUCATION IN NDOLA URBAN SECONDARY SCHOOLS OF COPPERBELT PROVINCE, ZAMBIA

This study investigated the attitudes of stakeholders toward school sexuality education in Ndola Urban District Secondary Schools. The descriptive qualitative research design was adopted for the study. Eight secondary schools, 377 teachers and 5, 737 pupils formed the population for the study. The sample for the study consisted of ninety (90) teachers, ninety (90) pupils and ninety (90) parents (with pupils in the schools) who were randomly selected. The instrument used for data collection was a close ended questionnaire of the five point Likert scale designed by the researcher. The instrument was both face and content validated by experts at Solusi University. To test the reliability of the instrument, a pilot study was carried out in two schools in the neighbouring Masaiti District using 40 respondents. The reliability of the instrument was determined using the Cronbach’s alpha reliability method and a reliability coefficient of 0.840 was obtained. Data collected was coded and analysed using the Statistical Package for Social Sciences. Descriptive statistics and the one-way analysis of variance were employed for data analysis. The result of the study revealed that the stakeholders (teachers, pupils and parents) in general had positive attitude toward the inclusion of sexuality education in the school curriculum. However, the teachers, pupils and parents had a negative attitude on the inclusion of topics like sexual pleasure and enjoyment, homosexuality as well as premarital sex as topics in the curriculum. There existed significant differences in the attitudes of stakeholders toward the inclusion of sexuality education in the curriculum as well as on the role of sexuality education in adolescent issues as revealed by the analysis of variance. The multiple comparisons showed that there existed significant differences in the attitudes of teachers and parents as well as in the attitudes of pupils and parents as it related to the role of sexuality education in adolescent issues an indication that pupils and teachers were in better agreement than their parents counterparts. In view of the positive attitude of stakeholders toward the inclusion and teaching of sexuality education in the school curriculum coupled with its benefits to adolescent sexual issues, it was recommended that sex education should be compulsory in schools

Explosive events - swirling transition region jets

In this paper, we extend our earlier work to provide additional evidence for an alternative scenario to explain the nature of so-called `explosive events'. The bi-directed, fast Doppler motion of explosive events observed spectroscopically in the transition region emission is classically interpreted as a pair of bidirectional jets moving upward and downward from a reconnection site. We discuss the problems of such a model. In our previous work, we focused basically on the discrepancy of fast Doppler motion without detectable motion in the image plane. We now suggest an alternative scenario for the explosive events, based on our observations of spectral line tilts and bifurcated structure in some events. Both features are indicative of rotational motion in narrow structures. We explain the bifurcation as the result of rotation of hollow cylindrical structures and demonstrate that such a sheath model can also be applied to explain the nature of the puzzling `explosive events'. We find that the spectral tilt, the lack of apparent motion, the bifurcation, and a rapidly growing number of direct observations support an alternative scenario of linear, spicular-sized jets with a strong spinning motion.Comment: 9 pages, 3 figures, accepted for publication in Solar Physic