Control of Arabidopsis apical-basal embryo polarity by antagonistic transcription factors.

Plants, similarly to animals, form polarized axes during embryogenesis on which cell differentiation and organ patterning programs are orchestrated. During Arabidopsis embryogenesis, establishment of the shoot and root stem cell populations occurs at opposite ends of an apical-basal axis. Recent work has identified the PLETHORA (PLT) genes as master regulators of basal/root fate, whereas the master regulators of apical/shoot fate have remained elusive. Here we show that the PLT1 and PLT2 genes are direct targets of the transcriptional co-repressor TOPLESS (TPL) and that PLT1/2 are necessary for the homeotic conversion of shoots to roots in tpl-1 mutants. Using tpl-1 as a genetic tool, we identify the CLASS III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIP III) transcription factors as master regulators of embryonic apical fate, and show they are sufficient to drive the conversion of the embryonic root pole into a second shoot pole. Furthermore, genetic and misexpression studies show an antagonistic relationship between the PLT and HD-ZIP III genes in specifying the root and shoot poles

Modelling the relationship between planning, control, perception and execution behaviours in interactive worksystems

This paper presents a model of planning carried out by interactive worksystems which attempts: 1. To describe the relationship between planning, control, perception and execution behaviours; 2. To make explicit how these may be distributed across the user and physically separate devices. Such a model, it is argued, is more suitable to support HCI design practice than theories of planning in cognitive science which focus on problem-solving methods and representations. To demonstrate the application of the model to work situations, it is illustrated by examples drawn from an observational study of secretarial office administration

Macromolecular separation through a porous surface

A new technique for the separation of macromolecules is proposed and investigated. A thin mesh with pores comparable to the radius of gyration of a free chain is used to filter chains according to their length. Without a field it has previously been shown that the permeability decays as a power law with chain length. However by applying particular configurations of pulsed fields, it is possible to have a permeability that decays as an exponential. This faster decay gives much higher resolution of separation. We also propose a modified screen containing an array of holes with barb-like protrusions running parallel to the surface. When static friction is present between the macromolecule and the protrusion, some of the chains get trapped for long durations of time. By using this and a periodic modulation of an applied electric field, high resolution can be attained.Comment: 18 pages latex, 6 postscript figures, using psfi

Marine exploration

Less than 50 years ago knowledge of the geology of the UK continental shelf (UKCS) was extremely limited. The BGS marine geoscience programme began about 40 years ago in response to the development of the UK oil and gas industry. The BGS was funded by the then Department of Energy to carry out a national mapping programme based on geophysical data, seabed samples and boreholes. By the 1990s, geological maps at a scale of 1:250 000 were published for the shelf regions showing seabed sediments, Quaternary geology and bedrock. The deeper water areas to the north and west continue to be explored with support from the oil industry. A series of regional reports, the offshore equivalent of the BGS regional guides, were published and reports for the Atlantic Margin will be published in 2010. MAREMAP is a new multidisciplinary environmental mapping programme designed to underpin the new marine industries and environmental issues

Climate change and heritage : responding to the crisis

Climate change poses a major threat to heritage of all kinds. Yet much of the work so far on climate change and heritage replicates aspects of the global heritage system, tending to emphasise a European perspective and focusing on the preservation of tangible heritage. We call for a broader understanding of climate change, particularly as it affects heritage in the developing world, especially that of indigenous peoples and small Island states. This is also a call for political engagement by heritage practitioners. We argue that in the struggle against climate change heritage practitioners can make a worthwhile contribution by arguing for a de-commodified form of heritage practice emphasizing the involvement of local communities and recognition of their cultural resources; that resists being coopted into economic growth strategies unless they supplant other forms of unsustainable development; that focuses on heritage as an alternative way of viewing resources and their use

Gemini Planet Imager Observational Calibrations II: Detector Performance and Calibration

The Gemini Planet Imager is a newly commissioned facility instrument designed to measure the near-infrared spectra of young extrasolar planets in the solar neighborhood and obtain imaging polarimetry of circumstellar disks. GPI's science instrument is an integral field spectrograph that utilizes a HAWAII-2RG detector with a SIDECAR ASIC readout system. This paper describes the detector characterization and calibrations performed by the GPI Data Reduction Pipeline to compensate for effects including bad/hot/cold pixels, persistence, non-linearity, vibration induced microphonics and correlated read noise.Comment: 11 pages, 6 figures. Proceedings of the SPIE, 9147-28

The masses, radii and luminosities of the components of U Geminorum

We present a phase-resolved spectroscopic study of the secondary star in the cataclysmic variable U Gem. We use our data to measure the radial velocity semi-amplitude, systemic velocity and rotational velocity of the secondary star. Combining this with literature data allows us to determine masses and radii for both the secondary star and white dwarf which are independent of any assumptions about their structure. We use these to compare their properties with those of field stars and find that both components follow field mass-radius relationships. The secondary star has the mass, radius, luminosity and photometric temperature of an M2 star, but a spectroscopic temperature of M4. The latter may well be due to a high metallicity. There is a troubling inconsistency between the radius of the white dwarf inferred from its gravitational redshift and inclination and that inferred from its temperature, flux, and astrometric distance. We find that there are two fundamental limits to the accuracy of the parameters we can derive. First the radial velocity curve of the secondary star deviates from a sinusoid, in part because of its asphericity (which can be modelled) and in part because the line flux is not evenly distributed over its surface. Second we cannot be certain which spectral type is the best match for the lines of the secondary star, and the derived rotational velocity is a function of the spectral type of the template star used.Comment: 12 pages, 10 figures. Accepted for MNRA

Podium Presentation: Promoting Holistic Health: Impact of Vocati on the Spiritual and Moral Development in Youth

Background: Approximately one out of every six individuals are adolescents between the ages of 10 to 19. Promoting health and reducing risks for this age group has life-long health and societal consequences. Evidence suggests positive and negative risk-taking behaviors cluster in this population. Models for the promotion of positive youth development have shifted in focus from avoidance of risk-taking behaviors to emphasis on psychosocial competence and holistic well-being. Evidence suggests spiritual wellbeing, regardless of conceptual definition, is more often than not associated with positive health outcomes and development in youth. However, few studies have included spiritual and moral constructs in program interventions and outcome metrics in this population. Purpose/Aims: The purpose of this project is to discuss the impact of Vocati, a youth theological institute intervention on adolescent moral and spiritual formation as a component of holistic health promotion. Methods/Approach: This study used a mixed-methods design. In 2016-2020, 4 cohorts of adolescents (n=57), age 15 - 18 years, from 3 states participated in a week-long theological summer intensive followed by a year-long monthly online discussion culminating in the implementation of a service/missional project. The Defining Issues Test, Version 2 (DIT-2) based on Kohlberg\u27s Stages of Moral Development and the Vocati Instrument Questionnaire (VIQ) a Likert-type questionnaire with open-ended questions were administered at baseline and program endpoints. Results: Data were analyzed using a mixed-model approach. The DIT2 mean scores between baseline and program endpoint were analyzed from matched pairs using a paired sample t-test for statistical analysis. The results supported N2 mean scores differences to be significantly higher, medium effect size at program end as compared to baseline (M = -5.85, SD = 10.95), t (36) = -3.25, p = .002, d = -.535). N2 score represents the most sophisticated level of moral judgment and corresponds to Kohlberg\u27s stage 5-6. The Vocati N2 mean scores were significantly higher (M=33.17. SD=11.51), t (1.14) compared to National Normative scores (M=30.97), t (.89), F(1.660), (p=.02). Statistically significant changes from empirical data from VIQ scores also supported significant differences in mean scores in five of six areas of spiritual development. Narrative themes were analyzed using a descriptive interpretive approach and were linked to positive prosocial competence skills reported in the literature. Conclusions: Youth participating in Vocati experienced a statistically significant increase in spiritual and moral development from baseline to program endpoint and national norms. Moral reasoning increased in N2 scores, reflecting, according to Kohlberg\u27s stages of moral development, the most sophisticated shift in moral reasoning and in the measures associated with spiritual formation. This finding is of particular importance as the N2 mean scores significantly changed from baseline to program end and were also statistically higher than the national norm of this measurement in youth. Clinical Implications: Findings from Vocati suggest the positive role exposure to theological content and spiritual formation practices may play in accelerating the development of moral reasoning and social competence skills associated with youth well-being. Further incorporation of these constructs within nursing interventions aimed at holistic health promotion activities targeting youth should be considered