The Seasonality of Physically Driven Export at Submesoscales in the Northeast Atlantic Ocean

Submesoscale dynamics O(1–100 km) are associated with enhanced vertical velocities and evolve on a time scale similar to that of biological production (hours to days). Here we consider an annual cycle of submesoscale dynamics and their relation to productivity and export in a small (20 × 20 km) region of the northeast Atlantic Ocean. In this region, a springtime bloom is initiated by restratification of the mixed layer in June, although intermittent shoaling of the mixed layer maintains phytoplankton populations throughout the year. An optical community index suggests a dominance of large species (e.g., diatoms) during spring and picophytoplankton during the winter. We review three types of submesoscale instabilities—mixed layer (baroclinic), gravitational, and symmetric—and consider the impact of each on export of fixed carbon out of the surface layer. Mixed layer instabilities can potentially export material out of the mixed layer during winter, although the vertical velocity across the base of the mixed layer is sensitive to the parameterization scheme. Symmetric instabilities, in contrast, provide a clear mechanism for rapid export out of the mixed layer. A crucial factor determining export potential is the strength of the pycnocline at the base of the mixed layer. Export production is sensitive to the degree of overlap that exists between intense submesoscale activity associated with deep mixed layers in the winter and high productivity associated with the spring restratification, meaning that physically driven export of fixed carbon will likely happen over a short time window during spring

Usability of Sound-Driven User Interfaces

The model for interacting with computing devices remains primarily focused on visual design. However, sound has a unique set of advantages. In this work, an experiment was devised where participants were tasked with identifying elements in an audio-only computing environment. The interaction relied on mouse movement and button presses for navigation. Experiment trials consisted of variations in sound duration, volume, and distinctness according to both experiment progress and user behavior. Participant interactions with the system were tracked to examine the usability of the interface. Preliminary results indicated the majority of participants mastered every provided test, but the total time spent finding the solution varied highly between participants. Suggestions for expanding the investigation and conducting future work are provided

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Eliminating Barriers: Connecting Seniors to Services in Chittenden County

Introduction. Physical activity programs for older adults help to improve physical, social, and emotional health and reduce impairments in activities of daily living1. In Chittenden county, less than 1⁄3 of older adults participate in programs, while 48% report that they would like to exercise more. Our aim was to identify barriers to participation in physical activity programs by older adults in Chittenden county, such as accessibility, transportation, health, affordability, and social isolation, and to identify strategies to overcome these barriers. Methods. 144 paper and electronic surveys were administered in Chittenden County, Vermont to assess use of group programs among older adults aged ≥ 50 years including transportation, motivation, preferences, advertisement, and barriers to access. A focus group explored aspects of ideal group activities for seniors. Results. 87.9% of respondents were active for two or more hours each week, while 46.5% had participated in group programming in the past 6 months. Group par- ticipation was significantly higher among physically active respondents (p=0.020). Motivators for participation in group activity included health benefits, social aspects, and physical activity, while the most cited barrier to attendance was timing conflicts. Respondents received information about programming via word of mouth, email, and online resources. Discussion. Overall, our findings indicate that the majority of respondents are highly active, however, they frequently experience barriers that prevent them from participating in group programming. We recommend offering flexible scheduling, advertising programming via word of mouth and email, and emphasizing program health benefits.https://scholarworks.uvm.edu/comphp_gallery/1260/thumbnail.jp

Structural investigations of CeIrIn5{_5} and CeCoIn5{_5} on macroscopic and atomic length scales

For any thorough investigation of complex physical properties, as encountered in strongly correlated electron systems, not only single crystals of highest quality but also a detailed knowledge of the structural properties of the material are pivotal prerequisites. Here, we combine physical and chemical investigations on the prototypical heavy fermion superconductors CeIrIn${_5}$ and CeCoIn${_5}$ on atomic and macroscopic length scale to gain insight into their precise structural properties. Our approach spans from enhanced resolution X-ray diffraction experiments to atomic resolution by means of Scanning Tunneling Microscopy (STM) and reveal a certain type of local features (coexistence of minority and majority structural patterns) in the tetragonal HoCoGa$_5$-type structure of both compounds.Comment: 8 pages, 5 figures, submitted to JPSJ (SCES 2013

An Automated System for Cryo-Electron Microscopy Sample Preparation

Cryo-electron microscopy (CryoEM) is a procedure that has become popular for imaging radiation intolerant structures under electron microscopes. CryoEM involves maintaining the sample at cryogenic temperatures throughout the imaging process This has the effect of minimizing damage caused by the electron beam, and results in higher quality images than can be obtained through more traditional imaging methods. The preparation of samples for cryo-electron microscopy studies is currently a labor and time intensive process. Samples must be applied to an imaging substrate under tightly controlled environmental conditions, formed into a thin film, vitrified with liquid ethane, and placed into temporary storage under cryogenic conditions. The grid preparation process is very sensitive to procedural factors, thus the successful creation of viable samples depends on tightly controlling the conditions under which grids are prepared. Several devices which automate portions of the specimen preparation process are currently in use; however, these systems heavily rely on a human operator to function properly. This thesis describes a system that is capable of fully automating the sample preparation process. The resulting system minimizes the need for human input during specimen preparation, improves process control, and provides similar levels of environmental control. Testing shows that the resulting system is capable of preparing samples without human interaction