Observations of stratigraphy and volcanism from guinevere and sedna planitiae, venus

Detailed mapping, using recently acquired full resolution photo-products and synthetic stereo data from the Magellan spacecraft, is used to investigate the stratigraphy and formation of landforms observed on Venus. The research focuses on two large contiguous plains, Guinevere and Sedna Planitiae. It has been suggested that distinct volcanic and deformational processes have operated throughout Venus within specific time periods. For example tesserae are considered to have only formed relatively early on in the visible venusian rock record. New observations of volcanic landforms within Guinevere and Sedna Planitia support a non-directional stratigraphy. Contrary to earlier models for the evolution of coronae, those in the study area have had a protracted history. Both Idem-Kuva and Heng-o display multiple phases of annulus formation (previously thought to occur during a specific stage of corona formation). Furthermore, annulus formation and rim topography formation do not necessarily coincide in space and time, as seen at Idem-Kuva, indicating that both large and small-scale deformational processes at coronae can be protracted. The amount and style of volcanism associated with the coronae studied here varies considerably. Predicted early stage volcanism is not observed at Idem-Kuva, Nissaba or Silvia Coronae, while Benten Corona shows multiple phases of volcanism which decrease in volume over time. A study of Sif and Gula Montes shows the two large shield volcanoes have a different overall morphology, summit structure and associated flow fields. Sif Mons is approximately circular in plan view, with a prominent summit caldera, with morphologically varying flow fields. In contrast, Gula Mons in elongate in plan view, surmounted by a rift joining two modified calderas, and is surrounded by more sinuous flows. Using terrestrial volcanoes as analogies, especially Mt. Etna, it is shown that the morphological differences between the two volcanoes may be a consequence of different internal and surrounding stress regimes

Effects of suspended sediments on the development of eggs and larvae of striped bass and white perch

The possible ecological effects of suspended sediments are manifold. Briefly, suspended sediments may cause an increased surface for microorganism growth, fewer temperature fluctuations, chemical adsorption or absorption, blanketing, mechanical-abrasive actions, and light penetration reduction (Cairns, 1968). Sherk and Cronin (1970) have pointed out that the above effects have been little studied in the estuarine environment. The ecological effects of suspended sediments on fish eggs and larvae may be of prime importance t o the C and D Canal area, an important spawning and primary nursery area for a variety of estuary: e species (Johnson,1972). This section discusses the effects of suspended sediment on the eggs and larvae of striped bass and white perch

Preparing for professional practice: how well does professional training equip health and social care practitioners to engage in evidence-based practice?

This paper reports on the findings of a study that aimed to explore how relevant initial training is in relation to evidence-based practice, and explore the perceptions of recently qualified practitioners about their confidence to engage in evidence-based practice. A cross-sectional postal survey was used to ascertain the views of nurses, social workers, occupational therapists and physiotherapists who had been qualified no longer than two years prior to the survey, and had qualified at one of three London Universities. Fifty questionnaires were sent out to each professional group (a sample of 200 overall) and there was a 43% response rate achieved. The results show a clear discrepancy between what are generally positive attitudes towards evidence-based practice and the value of research evidence and the infrequency with which they actually do make use of research resources and engage in evidence-based practice. A number of constraints to engagement in accessing and utilising evidence were identified

Adherence to Antibiotic Prophylaxis in Children with Vesicoureteral Reflux

Vesicoureteral reflux (VUR) affects approximately 1% of children and may predispose a child with a bladder infection to develop pyelonephritis and renal scarring. To prevent these potential sequelae, one accepted treatment option for VUR includes low-dose continuous antibiotic prophylaxis (CAP) to maintain urine sterility until the condition resolves. Despite the widespread use of CAP, little data exists regarding adherence to long-term antibiotic therapy. Not only will poor adherence to CAP potentially preclude the intended benefit, but also nonadherence with antibiotic regimens may carry untoward effects including unnecessary treatment changes for presumed antibiotic failure, emergence of resistant organisms, and compromised clinical trial outcomes. We present an overview of medication adherence in children with VUR, discuss possible consequences of nonadherence to antibiotic prophylaxis, and suggest ways to improve adherence. We raise awareness of issues related to nonadherence relevant to healthcare providers, investigators, and the community

Batman Meets Gagne: Analyzing Commercial Video Game Instruction through the Lens of Instructional Design

This paper will examine how Gagne’s Nine Events of Instruction (1992) may appear, perhaps inadvertently, within commercial games that guide the user from novice to expert player. By employing a qualitative artifact analysis methodology, we examine a popular action adventure video game to determine if game designers encourage players to build game expertise by employing similar events to Gagne’s instructional design model. We demonstrate that our artifact of analysis does consistently employ Gagne’s events, though often in a manner unique to a digitally mediated space. We conclude that an experiential game setting has the potential to be a platform for instructional delivery

The surface ectoderm exhibits spatially heterogenous tension that correlates with YAP localisation during spinal neural tube closure in mouse embryos

The single cell layer of surface ectoderm (SE) which overlies the closing neural tube (NT) plays a crucial biomechanical role during mammalian NT closure (NTC), challenging previous assumptions that it is only passive to the force-generating neuroepithelium (NE). Failure of NTC leads to congenital malformations known as NT defects (NTDs), including spina bifida (SB) and anencephaly in the spine and brain respectively. In several mouse NTD models, SB is caused by misexpression of SE-specific genes and is associated with disrupted SE mechanics, including loss of rostrocaudal cell elongation believed to be important for successful closure. In this study, we asked how SE mechanics affect NT morphology, and whether the characteristic rostrocaudal cell elongation at the progressing closure site is a response to tension anisotropy in the SE. We show that blocking SE-specific E-cadherin in ex utero mouse embryo culture influences NT morphology, as well as the F-actin cable. Cell border ablation shows that cell shape is not due to tension anisotropy, but that there are regional differences in SE tension. We also find that YAP nuclear translocation reflects regional tension heterogeneity, and that its expression is sensitive to pharmacological reduction of tension. In conclusion, our results confirm that the SE is a biomechanically important tissue for spinal NT morphogenesis and suggest a possible role of spatial regulation of cellular tension which could regulate downstream gene expression via mechanically-sensitive YAP activity