Alien Registration- Daigle, Eva T. (Madawaska, Aroostook County)

https://digitalmaine.com/alien_docs/24929/thumbnail.jp

Social Presence as Best Practice: The Online Classroom Needs to Feel Real

As universities around the world stopped delivering face to face classes, the nonintentional creation of many online digital learning spaces has led to much speculation on “best practices” for virtual course delivery. Our evidence shows that the highest educational value comes from optimizing the “social presence” of your classroom environment. Using data collected from an undergraduate political science research methods course prior to the COVID-19 pandemic, across 3 semesters at a large public university, we find by maximizing perceptual social presence - or the feeling that a student is actively engaged in a “real” classroom environment, students report greater satisfaction with their education, perform at a higher level, and have greater knowledge gains. Interacted with the course modality, the course performance impact of social presence is amplified for those taking coursework online versus taking it face to face. The limitation of asynchronous delivery adopted as “best practice” by many colleges is the substantial social presence deficit produced, and as a result, we recommend faculty and curriculum developers promote the intentional hybridization of asynchronous content with scheduled synchronous learning opportunities so that faculty and students can “keep it real”

Teaching Political Science Research Methods Across Delivery Modalities: Comparing Outcomes Between Face-to-Face and Distance-Hybrid Courses

What delivery modality is most effective in teaching undergraduate, political science research methods? Using systematically collected data from two academic terms and employing a quasi-experimental design, this paper explores variation in learning outcomes between face-to-face and distance-hybrid course offerings. Variation in the dependent variable is observed through measuring attrition (drop or failure), course performance among those who pass, and course satisfaction. While any evidence of difference in attrition rates is marginal when controlling for sex, age, university experience, a background in similar coursework, or whether the course is taken by a major, there is no evidence that modality predicts performance among those who successfully complete the course. Distance-hybrid learners are less satisfied with the class overall, unless you control for knowledge gains, math anxiety, and especially social presence. Perceptions of a learning community predict satisfaction for learners across both modalities, but when modeled controlling for other subjective outcomes, we predict higher satisfaction for distance learners. This suggests that the best pathway to equalize outcomes across delivery modalities is to work hard to overcome the social presence gap experienced by students learning in a distance-hybrid environment

Affine T-varieties of complexity one and locally nilpotent derivations

Let X=spec A be a normal affine variety over an algebraically closed field k of characteristic 0 endowed with an effective action of a torus T of dimension n. Let also D be a homogeneous locally nilpotent derivation on the normal affine Z^n-graded domain A, so that D generates a k_+-action on X that is normalized by the T-action. We provide a complete classification of pairs (X,D) in two cases: for toric varieties (n=\dim X) and in the case where n=\dim X-1. This generalizes previously known results for surfaces due to Flenner and Zaidenberg. As an application we compute the homogeneous Makar-Limanov invariant of such varieties. In particular we exhibit a family of non-rational varieties with trivial Makar-Limanov invariant.Comment: 31 pages. Minor changes in the structure. Fixed some typo

Linking basin-scale and pore-scale gas hydrate distribution patterns in diffusion-dominated marine hydrate systems

The goal of this study is to computationally determine the potential distribution patterns of diffusion-driven methane hydrate accumulations in coarse-grained marine sediments. Diffusion of dissolved methane in marine gas hydrate systems has been proposed as a potential transport mechanism through which large concentrations of hydrate can preferentially accumulate in coarse-grained sediments over geologic time. Using one-dimensional compositional reservoir simulations, we examine hydrate distribution patterns at the scale of individual sand layers (1-20 m thick) that are deposited between microbially active fine-grained material buried through the gas hydrate stability zone (GHSZ). We then extrapolate to two-dimensional and basin-scale three-dimensional simulations, where we model dipping sands and multilayered systems. We find that properties of a sand layer including pore size distribution, layer thickness, dip, and proximity to other layers in multilayered systems all exert control on diffusive methane fluxes toward and within a sand, which in turn impact the distribution of hydrate throughout a sand unit. In all of these simulations, we incorporate data on physical properties and sand layer geometries from the Terrebonne Basin gas hydrate system in the Gulf of Mexico. We demonstrate that diffusion can generate high hydrate saturations (upward of 90%) at the edges of thin sands at shallow depths within the GHSZ, but that it is ineffective at producing high hydrate saturations throughout thick (greater than 10 m) sands buried deep within the GHSZ. Furthermore, we find that hydrate in fine-grained material can preserve high hydrate saturations in nearby thin sands with burial

H-alpha Kinematics of the SINGS Nearby Galaxies Survey. II

This is the second part of an H-alpha kinematics follow-up survey of the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample. The aim of this program is to shed new light on the role of baryons and their kinematics and on the dark/luminous matter relation in the star forming regions of galaxies, in relation with studies at other wavelengths. The data for 37 galaxies are presented. The observations were made using Fabry-Perot interferometry with the photon-counting camera FaNTOmM on 4 different telescopes, namely the Canada-France-Hawaii 3.6m, the ESO La Silla 3.6m, the William Herschel 4.2m, and the Observatoire du mont Megantic 1.6m telescopes. The velocity fields are computed using custom IDL routines designed for an optimal use of the data. The kinematical parameters and rotation curves are derived using the GIPSY software. It is shown that non-circular motions associated with galactic bars affect the kinematical parameters fitting and the velocity gradient of the rotation curves. This leads to incorrect determinations of the baryonic and dark matter distributions in the mass models derived from those rotation curves.Comment: 18 pages, 5 figures, 4 tables. Accepted for publication in MNRAS. All high-res. figures are available at http://www.astro.umontreal.ca/fantomm/singsII

Virulence not linked with vegetative compatibility groups in Australian cotton Verticillium dahliae isolates

Verticillium dahliae, the causal agent of Verticillium wilt, is a soil-borne ascomycete that infects numerous agriculturally important crops globally, including cotton. As a billion-dollar industry, cotton is economically important to Australia and the management of disease such as Verticillium wilt is key for the success of the industry. Internationally, defoliating V. dahliae isolates belonging to Vegetative Compatibility Group (VCG) 1A cause severe damage to cotton, while non-defoliating VCG2A isolates result in significantly less disease. However, in Australia, VCG2A is causing more severe damage to crops in the field than the defoliating VCG1A. This study aimed to replicate field observations in controlled greenhouse conditions. We examined and compared disease symptoms on a range of Australian commercial cotton varieties when inoculated with different V. dahliae VCGs. Seedlings were root dipped in conidial suspensions and assessed over seven weeks. The final disease score, disease over time and root length were analysed. Plant mortality resulted from both V. dahliae VCG1A and VCG2A isolates across all cotton varieties used, confirming that there are virulent VCG2A isolates present in Australia. To our knowledge, although virulent on other plant hosts, V. dahliae VCG2A has not previously been reported to be highly virulent in cotton. We infer that virulence cannot be defined solely by VCG in Australian V. dahliae isolates causing disease in cotton