Physical Constraints to Aquatic Plant Growth in New Zealand Lakes

The nature of aquatic plant communities often defines benthic habitat within oligotrophic and mesotrophic lakes and lake management increasingly recognizes the importance of maintaining plant diversity in order to sustain biological diversity and capacity within lakes. We have developed simple statistical relationships between key physical and vegetation variables that define the habitat requirements, or “habitat-templates”, of key vegetation types to facilitate management of plant communities in New Zealand lakes. Statistical relationships were derived from two datasets. The first was a multi-lake dataset to determine the effects of water level fluctuation and water clarity. The second dataset was from a comprehensive shoreline survey of Lake Wanaka, which allowed us to examine within-lake variables such as beach slope and wave action. Sufficient statistical relationships were established to develop a habitat template for each of the major species or assemblages. The relationships suggested that the extent and diversity of shallow-growing species was related to a combination of the extent of water level fluctuation and wave exposure. (PDF contains 9 pages.

Spatial interference from well-separated condensates

We use magnetic levitation and a variable-separation dual optical plug to obtain clear spatial interference between two condensates axially separated by up to 0.25 mm -- the largest separation observed with this kind of interferometer. Clear planar fringes are observed using standard (i.e. non-tomographic) resonant absorption imaging. The effect of a weak inverted parabola potential on fringe separation is observed and agrees well with theory.Comment: 4 pages, 5 figures - modified to take into account referees' improvement

The Neuroscience of Preferences

The expression of preference reflects the influence of two broad modes of judgment—intuition and deliberation (Kahneman and Frederick 2002). The intuitive mode includes emotional reactions (e.g. Loewenstein 1996), but it also includes heuristic process which are largely perceptual or cognitive in nature. Intuitive processes occur early in a judgment process; they are fast and largely automatic. This is in contrast with deliberative processes which tend to occur later in a judgement process, are slower, and are more controlled. Intuitive and deliberative processes interact with each other, although they are often in conflict, and there is some evidence that they are anatomically separated in the brain

A large magnetic storage ring for Bose-Einstein condensates

Cold atomic clouds and Bose-Einstein condensates have been stored in a 10cm diameter vertically-oriented magnetic ring. An azimuthal magnetic field enables low-loss propagation of atomic clouds over a total distance of 2m, with a heating rate of less than 50nK/s. The vertical geometry was used to split an atomic cloud into two counter-rotating clouds which were recombined after one revolution. The system will be ideal for studying condensate collisions and ultimately Sagnac interferometry.Comment: 4 pages, 5 figure

Analysis of Continuous Gait Data Requires Temporal Alignment of Gait Phases

A statistical method for comparing time-continuous curves, such as the kinematics of gait cycles, is statistical parametric mapping analysis (SPM) (Pataky, 2010). According to a recent study, SPM results were sensitive to how each stride\u27s beginning was defined (Honert & Pataky, 2021). Nonetheless, for meaningful comparisons between gait cycles, temporal alignment of phases within a stride may be required (Helwig et al., 2011). With both temporally aligned and unaligned gait data, the goal was to evaluate SPM results for different walking speeds using various gait cycle definitions. Participants in this study were 10 young, healthy adults. To figure out the preferred overground speed, an instrumented mat was employed. While subjects walked at speeds of 80, 90, 100, 110, and 120% of the preferred pace, a ten-camera Vicon motion capture system, Conventional Gait Model 2.4, and Nexus 2.13 software were used to collect biomechanical data of the legs. Using customized MATLAB code, 100 gait cycles at each speed for each participant were chosen and temporally aligned to the five gait phases (loading response, mid and terminal stance, pre-swing, initial and mid swing, and terminal swing) based on kinematic events of interest. Five distinct stride definitions were used in SPM using a one-way repeated measures ANOVA, both with and without the temporal alignment of gait phases. SPM results for unaligned gait data varied between different stride definitions but were consistent for data that was temporally aligned. SPM\u27s results for aligned data consistently demonstrate that time normalization, not stride definition, is what makes SPM sensitive. For a point-by-point comparison of gait kinematics using SPM, the phases must be time-aligned.https://digitalcommons.odu.edu/gradposters2023_healthsciences/1010/thumbnail.jp

06161 Abstracts Collection -- Simulation and Verification of Dynamic Systems

From 17.04.06 to 22.04.06, the Dagstuhl Seminar 06161 ``Simulation and Verification of Dynamic Systems\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available