Delivering authentic online practical science teaching – geoscience perspectives from the OpenScience Laboratory

Teaching practical science at a distance is challenging – how do you give students studying online a meaningful practical experience? In July 2013, the Open University (OU) launched the Wolfson OpenScience Laboratory (OSL) to deliver a wide a range of authentic practical science activities for their distance learning undergraduates. Prompted by the recognition that modern science is increasingly conducted via a computer screen (e.g. remote sensing, Martian fieldwork), the OSL presents a variety of opportunities for students to observe, investigate, gather and analyse data. The rationale is to foster problem-based, active learning, which has been proven effective by numerous studies. Simulation is kept to a minimum; most activities either generate or use real data, with authentic anomalies and ‘noise’ included – an aspect valued by the students. Geoscience is rooted in raw data collected during practical investigations, notably fieldwork. A key skill is observation, so the OSL includes digital collections of minerals, rocks and fossils, as zoomable, high resolution images and 360° videos for the 3D perspective. The Virtual Microscope enables petrographic examination of thin sections using high-quality zoomable images, in both plane- and cross polarised light, with rotation of the sample for certain points of interest. There is a virtual field trip based in a multi-user virtual environment (MUVE), as well as an exercise on maps and landforms. Developed primarily for OU undergraduates, many of the assets in the OSL are being made more openly accessible, with free registration. We are developing partnerships with other universities and schools, both as users and contributors to further assets (e.g. thin section collections). We have also gathered feedback from several surveys of OU undergraduates, as well as external users. Feedback on the pedagogical aspects of the OSL is broadly positive, with some assets (e.g. the virtual microscope) garnering particular praise; respondents value the potential for interaction with experts but also desire an explicit connection to the materials’ original field context. However, technological issues at times present a barrier to learning – perhaps reflecting the high diversity of OU cohorts, especially in terms of their individual hardware, software and IT skills. Some students resent the time investment required to master specialised scientific software, though it could be argued that acquiring such IT skills is an essential part of practising modern science

Diel variation in vertical distribution of an offshore ichthyoplankton community off the Oregon coast

We examined the diel ver-tical distribution, concentration, and community structure of ichthyoplank-ton from a single station 69 km off the central Oregon coast in the northeast Pacific Ocean. The 74 depth-stratified samples yielded 1571 fish larvae from 20 taxa, representing 11 families, and 128 fish eggs from 11 taxa within nine families. Dominant larval taxa were Sebastes spp. (rockfishes), Stenobra-chius leucopsarus (northern lampfish), Tarletonbeania crenularis (blue lan-ternfish), and Lyopsetta exilis (slender sole), and the dominant egg taxa were Sardinops sagax (Pacific sardine), Icichthys lockingtoni (medusafish), and Chauliodus macouni (Pacific viperfish). Larval concentrations generally increased from the surface to 50 m, then decreased with depth. Larval concentrations were higher at night than during the day, and there was evidence of larval diel vertical migration. Depth stratum was the most important factor explaining variability in larval and egg concentrations

Egg parasitoid exploitation of plant volatiles induced by single or concurrent attack of a zoophytophagous predator and an invasive phytophagous pest

Zoophytophagous insect predators can induce physiological responses in plants by activating defence signalling pathways, but whether plants can respond to facultative phytophagy by recruiting natural enemies remains to be investigated. In Y-tube olfactometer bioassays, using a system including a Vicia faba plant, the zoophytophagous predator Podisus maculiventris and the egg parasitoid Telenomus podisi, we first demonstrated that T. podisi females are attracted by broad bean plants damaged by feeding activity of P. maculiventris and on which host egg masses had been laid, while they are not attracted by undamaged plants or plants damaged by feeding activity alone. In a second experiment, we evaluated the impact of the invasive phytophagous pest Halyomorpha halys on this plant volatile-mediated tritrophic communication. Results showed that the invasive herbivorous adults do not induce plants to recruit the native egg parasitoid, but they can disrupt the local infochemical network. In fact, T. podisi females are not attracted by volatiles emitted by plants damaged by H. halys feeding alone or combined with oviposition activity, nor are they attracted by plants concurrently infested by P. maculiventris and H. halys, indicating the specificity in the parasitoid response and the ability of the invasive herbivore in interrupting the semiochemical communication between plants and native egg parasitoids. To the best of our knowledge, this is the first study showing that zoophytophagous predator attacks induce indirect plant defences similarly to those defence strategies adopted by plants as a consequence of single or concurrent infestations of herbivorous insects

Control of the Onset of Filamentation in Condensed Media

Propagation of intense, ultrashort laser pulses through condensed media like crystals of BaF$_2$ and sapphire results in the formation of filaments. We demonstrate that the onset of filamentation may be controlled by rotating the plane of polarization of incident light. We directly visualize filamentation in BaF_2 via six-photon absorption-induced fluorescence and, concomitantly, by probing the spectral and spatial properties of white light that is generated.Comment: To appear in Phys. Rev.

Adolescent Pregnancy and Loneliness

This descriptive study explored loneliness among pregnant adolescents in a southeastern metropolitan area. Numerous psychosocial variables of the special population of pregnant teens remain to be studied. One such variable is loneliness, a feeling often experienced by adolescents. The present study hypothesized that loneliness may occur during adolescent pregnancy. To date, one study exists (Diiorio & Riley, 1988) of loneliness and adolescent pregnancy. The problem statement was: Does loneliness exist among pregnant adolescents? Three research questions were addressed: Within this sample: 1. To what extent does loneliness exist? 2. Is loneliness more frequent during certain ages? 3. Do pregnant black and white adolescents differ in the extent to which they experience loneliness? Participants between the ages of 14 and 18 receiving prenatal care in public health clinics and a university affiliated obstetric clinic were selected for the study. The final sample size was 78. The loneliness study was conducted as part of a larger longitudinal study, Nursing Role Supplementation for Adolescent Parents (NIH #1R01NR01939-01A1). The dependent variable, loneliness, was measured by the Revised UCLA Loneliness Scale (Russell, Peplau, & Cutrona, 1980), a 20-item Likert-type instrument. Possible scores on the tool ranged from 20 to 80, with 80 constituting the loneliest end of the continuum. The extent of loneliness was determined by the summation of numerical responses. Data were analyzed by two methods: (a) analysis of variance (ANOVA), to determine any differences between age and loneliness score, and (b) the t-test for two independent samples, in order to examine differences in mean loneliness scores between blacks and whites in the sample. Scores ranged from 25 to 58. Low to moderate loneliness existed among the sample; however, loneliness did not exist in greater amplitude than among nonpregnant adolescents in other studies reviewed. No significant relationship was found between age of participants and loneliness scores. Furthermore, differences in loneliness scores between blacks and whites were not statistically significant. Finally, pregnancy may not intensify loneliness for adolescents. On the other hand, pregnancy did not diminish loneliness among pregnant adolescents in this sample

Highly charged ions in Penning traps, a new tool for resolving low lying isomeric states

The use of highly charged ions increases the precision and resolving power, in particular for short-lived species produced at on-line radio-isotope beam facilities, achievable with Penning trap mass spectrometers. This increase in resolving power provides a new and unique access to resolving low-lying long-lived ($T_{1/2} > 50$ ms) nuclear isomers. Recently, the $111.19(22)$ keV (determined from $\gamma$-ray spectroscopy) isomeric state in $^{78}$Rb has been resolved from the ground state, in a charge state of $q=8+$ with the TITAN Penning trap at the TRIUMF-ISAC facility. The excitation energy of the isomer was measured to be $108.7(6.4)$ keV above the ground state. The extracted masses for both the ground and isomeric states, and their difference, agree with the AME2003 and Nuclear Data Sheet values. This proof of principle measurement demonstrates the feasibility of using Penning trap mass spectrometers coupled to charge breeders to study nuclear isomers and opens a new route for isomer searches.Comment: 8 pages, 6 figure

Dynamic Nonlinear X-waves for Femtosecond Pulse Propagation in Water

Recent experiments on femtosecond pulses in water displayed long distance propagation analogous to that reported in air. We verify this phenomena numerically and show that the propagation is dynamic as opposed to self-guided. Furthermore, we demonstrate that the propagation can be interpreted as due to dynamic nonlinear X-waves whose robustness and role in long distance propagation is shown to follow from the interplay between nonlinearity and chromatic dispersion.Comment: 4 page

First direct mass-measurement of the two-neutron halo nucleus 6He and improved mass for the four-neutron halo 8He

The first direct mass-measurement of $^{6}$He has been performed with the TITAN Penning trap mass spectrometer at the ISAC facility. In addition, the mass of $^{8}$He was determined with improved precision over our previous measurement. The obtained masses are $m$($^{6}$He) = 6.018 885 883(57) u and $m$($^{8}$He) = 8.033 934 44(11) u. The $^{6}$He value shows a deviation from the literature of 4$\sigma$. With these new mass values and the previously measured atomic isotope shifts we obtain charge radii of 2.060(8) fm and 1.959(16) fm for $^{6}$He and $^{8}$He respectively. We present a detailed comparison to nuclear theory for $^6$He, including new hyperspherical harmonics results. A correlation plot of the point-proton radius with the two-neutron separation energy demonstrates clearly the importance of three-nucleon forces.Comment: 4 pages, 2 figure