Sense of competence, autonomy and relatedness during primary-secondary transition: children express their own experiences

This paper contributes a greater understanding of the importance of a sense of competence, autonomy and relatedness to children experiencing the primarysecondary schooling transition, drawing on the perspectives of the young people themselves. We address how the perspectives of transitioning children can further substantiate and illuminate Ryan and Deci’s Self Determination Theory (SDT; Ryan and Deci, 2019). SDT claims that satisfaction of a person’s needs for competence (attainment and confidence), autonomy (self-direction and capacity to critique) and relatedness (feeling affectively bonded to others) allows them to achieve ‘positiveexperience and wellness outcomes’ (p.219). We draw on data from two research projects, one a survey study of 288 transitioning children; and one a life-history study of 23 transitioning children. Our findings illustrated the potential benefits of policymakers giving priority to a wider range of conceptions of competence beyond attainment in mathematics/English, in order to support transitioning children’s sense of competence including their self-confidence. Findings also highlighted the need to nurture children’s capacity to recognise and direct their own schooling trajectories more autonomously, directing their energies into engagement with learning and relationships rather than into riling against controls or seeking to avoid humiliation and punishment. Most positively, our data manifested children’s high levels of relatedness to both peers and teachers as they transitioned to new secondary schools. And above all, our data emphasised and exemplified the need for relatedness to accompany children’s strong sense of competence and autonomy during transition

A discrete slug population model determined by egg production

Slugs are significant pests in agriculture (as well as a nuisance to gardeners), and it is therefore important to understand their population dynamics for the construction of efficient and effective control measures. Differential equation models of slug populations require the inclusion of large (variable) temporal delays, and strong seasonal forcing results in a non-autonomous system. This renders such models open to only a limited amount of rigorous analysis. In this paper, we derive a novel batch model based purely upon the quantity of eggs produced at different times of the year. This model is open to considerable reduction; from the resulting two variable discrete-time system it is possible to reconstruct the dynamics of the full population across the year and give conditions for extinction or global stability and persistence. Furthermore, the steady state temporal population distribution displays qualitatively different behavior with only small changes in the survival probability of slugs. The model demonstrates how small variations in the favorability of different years may result in widely different slug population fluctuations between consecutive years, and is in good agreement with field data

The TANAMI Program

TANAMI (Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry) is a monitoring program to study the parsec-scale structures and dynamics of relativistic jets in active galactic nuclei (AGN) of the Southern Hemisphere with the Long Baseline Array and associated telescopes. Extragalactic jets south of -30 degrees declination are observed at 8.4 GHz and 22 GHz every two months at milliarcsecond resolution. The initial TANAMI sample is a hybrid radio and gamma-ray selected sample since the combination of VLBI and gamma-ray observations is crucial to understand the broadband emission characteristics of AGN.Comment: Confernce Proceedings for "X-ray Astronomy 2009" (Bologna), 3 pages, 3 figures, needs cls-fil

Polaron and bipolaron dispersion curves in one dimension for intermediate coupling

Bipolaron energies are calculated as a function of wave vector by a variational method of Gurari appropriate for weak or intermediate coupling strengths, for a model with electron-phonon interactions independent of phonon wave vectors and a short-ranged Coulomb repulsion. It is assumed that the bare electrons have a constant effective mass. A two-parameter trial function is taken for the relative motion of the two electrons in the bipolaron. Energies of bipolarons are compared with those of two single polarons as a function of wave vector for various parameter values. Results for effective masses at the zone center are also obtained. Comparison is made with data of other authors for bipolarons in the Hubbard-Holstein model, which differs mainly from the present model in that it has a tight-binding band structure for the bare electrons.Comment: 11 pages including six figures. Physical Review B, to be publishe

TANAMI - Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry

We present a summary of the observation strategy of TANAMI (Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry), a monitoring program to study the parsec-scale structure and dynamics of relativistic jets in active galactic nuclei (AGN) of the Southern Hemisphere with the Australian Long Baseline Array (LBA) and the trans-oceanic antennas Hartebeesthoek, TIGO, and O'Higgins. TANAMI is focusing on extragalactic sources south of -30 degrees declination with observations at 8.4 GHz and 22 GHz every ~2 months at milliarcsecond resolution. The initial TANAMI sample of 43 sources has been defined before the launch of the Fermi Gamma Ray Space Telescope to include the most promising candidates for bright gamma-ray emission to be detected with its Large Area Telescope (LAT). Since November 2008, we have been adding new sources to the sample, which now includes all known radio- and gamma-ray bright AGN of the Southern Hemisphere. The combination of VLBI and gamma-ray observations is crucial to understand the broadband emission characteristics of AGN and the nature of relativistic jets.Comment: Conference proceedings "2009 Fermi Symposium" eConf Proceedings C09112

Photorespiration: metabolic pathways and their role in stress protection

Photorespiration results from the oxygenase reaction catalysed by ribulose-1,5-bisphosphate carboxylase/ oxygenase. In this reaction glycollate-2-phosphate is produced and subsequently metabolized in the photorespiratory pathway to form the Calvin cycle intermediate glycerate-3-phosphate. During this metabolic process, CO2 and NH3 are produced and ATP and reducing equivalents are consumed, thus making photorespiration a wasteful process. However, precisely because of this ine¤ciency, photorespiration could serve as an energy sink preventing the overreduction of the photosynthetic electron transport chain and photoinhibition, especially under stress conditions that lead to reduced rates of photosynthetic CO2 assimilation. Furthermore, photorespiration provides metabolites for other metabolic processes, e.g. glycine for the synthesis of glutathione, which is also involved in stress protection. In this review, we describe the use of photorespiratory mutants to study the control and regulation of photorespiratory pathways. In addition, we discuss the possible role of photorespiration under stress conditions, such as drought, high salt concentrations and high light intensities encountered by alpine plants

Phase Fluctuations and Pseudogap Properties: Influence of Nonmagnetic Impurities

The presence of nonmagnetic impurities in a 2D ``bad metal'' depresses the superconducting Berezinskii-Kosterlitz-Thouless transition temperature, while leaving the pairing energy scale unchanged. Thus the region of the pseudogap non-superconducting phase, where the modulus of the order parameter is non-zero but its phase is random, and which opens at the pairing temperature is substantially bigger than for the clean system. This supports the premise that fluctuations in the phase of the order parameter can in principle describe the pseudogap phenomena in high-$T_c$ materials over a rather wide range of temperatures and carrier densities. The temperature dependence of the bare superfluid density is also discussed.Comment: 11 pages, LaTeX, 1 EPS figure; final version to appear in Low.Temp.Phy

Geochemical Processes and Controls Affecting Water Quality of the Karst Area of Big Creek near Mt. Judea, Arkansas

Karst regions typically are considered to be vulnerable with respect to various land-use activities, owing to the intimate association of surface and groundwater and lack of contaminant attenuation provided by most karst aquifers. Inasmuch as the soluble rocks of the karst landscape can be dissolved to create large, rapid-flow zones that compete successfully with surface streams, groundwater and subsurface flow represent a much larger component of the hydrologic budget in karst regions than in areas where non-soluble rocks predominate. Karst areas typically are distinguished by being unique, but some general approaches can be applied to characterize the hydrology of the area. These approaches include an evaluation of the degree of karstification, the hydrologic attributes of the groundwater flow system, the baseline water quality, the time-of-travel through the karst flow system, and the general flux moving through the system. The nature of potential contaminants and their total mass and range of concentrations are critical to understanding the potential environmental risk. This study describes the characterization of the baseline water quality of the shallow karst Boone aquifer and surface streams and springs to determine major processes and controls affecting water quality in the region, and to assess 2 years of waste spreading. Parameters evaluated include major constituents, contaminants and their breakdown products from the industrial operation of a concentrated animal-feeding operation (CAFO) on Big Creek, the indicator pathogen, E. coli, dissolved oxygen, selected trace metals, and other ancillary water-quality attributes that are directly observable in the environment. Determination of pre-CAFO water quality was accomplished by sampling approximately 40 sites that included wells, springs, and streams