Synchronization and Stability in Noisy Population Dynamics

We study the stability and synchronization of predator-prey populations subjected to noise. The system is described by patches of local populations coupled by migration and predation over a neighborhood. When a single patch is considered, random perturbations tend to destabilize the populations, leading to extinction. If the number of patches is small, stabilization in the presence of noise is maintained at the expense of synchronization. As the number of patches increases, both the stability and the synchrony among patches increase. However, a residual asynchrony, large compared with the noise amplitude, seems to persist even in the limit of infinite number of patches. Therefore, the mechanism of stabilization by asynchrony recently proposed by R. Abta et. al., combining noise, diffusion and nonlinearities, seems to be more general than first proposed.Comment: 3 pages, 3 figures. To appear in Phys. Rev.

The Lantern Vol. 2, No. 2, March 1934

• Fulfillment Through Expression • Ole Man Ennis • Nos Illusions by Philippe Vallee • A Celtic May Day Festival • Dew Drops • Baker Street Fiction • March Winds • Winter Sunset • Book Review: No Second Spring • A Thought • The Cask of Amontillado • Illustrationhttps://digitalcommons.ursinus.edu/lantern/1002/thumbnail.jp

The Lantern Vol. 1, No. 1, May 1933

• Remember: Translation of Rappelle-toi by Alfred de Musset • Lighting the Lantern • Footfalls • To a Lovely Lady • The Sons of Martha • Strategy • Lumine Lunae • Poetry in Retrospect • Nirvana • A Domestic Episode • At Night • Haman and Hitler • This is What He Said • Bookocracy • Four Loves • Cities and Personalitieshttps://digitalcommons.ursinus.edu/lantern/1000/thumbnail.jp

The Lantern Vol. 2, No. 1, December 1933

• Petition • Keep it Burning! • Jes\u27 Before Christmas • Noel: Translation from Theophile Gautier • A Young Jew Meets Jesus • Book Review: Little Man, What Now? • Book Review: Thunder and Dawn • Continuity • La Veille de Noel (Reflexions d\u27un Provincial) • Noel Sceptique par Jules LaFargue • Horizon • Winter Night • Linoleum Cutshttps://digitalcommons.ursinus.edu/lantern/1001/thumbnail.jp

Simulating Mechanisms for Dispersal, Production and Stranding of Small Forage Fish in Temporary Wetland Habitats

Movement strategies of small forage fish (\u3c8 cm total length) between temporary and permanent wetland habitats affect their overall population growth and biomass concentrations, i.e., availability to predators. These fish are often the key energy link between primary producers and top predators, such as wading birds, which require high concentrations of stranded fish in accessible depths. Expansion and contraction of seasonal wetlands induce a sequential alternation between rapid biomass growth and concentration, creating the conditions for local stranding of small fish as they move in response to varying water levels. To better understand how landscape topography, hydrology, and fish behavior interact to create high densities of stranded fish, we first simulated population dynamics of small fish, within a dynamic food web, with different traits for movement strategy and growth rate, across an artificial, spatially explicit, heterogeneous, two-dimensional marsh slough landscape, using hydrologic variability as the driver for movement. Model output showed that fish with the highest tendency to invade newly flooded marsh areas built up the largest populations over long time periods with stable hydrologic patterns. A higher probability to become stranded had negative effects on long-term population size, and offset the contribution of that species to stranded biomass. The model was next applied to the topography of a 10 km × 10 km area of Everglades landscape. The details of the topography were highly important in channeling fish movements and creating spatiotemporal patterns of fish movement and stranding. This output provides data that can be compared in the future with observed locations of fish biomass concentrations, or such surrogates as phosphorus ‘hotspots’ in the marsh

sTable Sawhorse: A Compact Folding, Sturdy Sawhorse Designed to be Light Weight And Save Space

The sTable Sawhorse is a composite, clamshell-style folding structure designed to be a mobile set of legs to support and raise objects to an appropriate work height. Designed with space saving in mind while folded, the sawhorse takes up minimal space while not in use. Manufactured with a woven fiberglass c-channel body, epoxy resin, and a foam core, the sTable Sawhorse is lightweight and robust. A large, flat top work surface allows for better contact and control of items placed on it. A wide footprint also allows for a very stable structure. This product is unique in that it combines a light-weight frame with the strength of similar bulkier and heavier alternatives. Consisting of two identical halves, the sawhorse is simple in design and construction. Testing will be conducted to determine the strength and the UV resistance of the legs as well as the overall stability of the structure

An assessment of capacity building activities for common interest farmer groups in Bangladesh

This study examines how “farmers from the Common Interest Group (CIG)” have changed their capacity levels due to participating in Bangladesh’s National Agricultural Technology Program (NATP). A mixed-method design was used to collect data from 120 rice and vegetable farmers. Results show that most respondents (above 75 per cent) agree that NATP initiatives, particularly group-based extension services, developed their capacity in different cultivation techniques, resource utilisation, farm inputs, communication behaviour, market access, and involvement in farmer organisations (FOs)/community-based organisations (CBOs). This study concludes that the concept of CIGs should be incorporated into the existing extension system following the termination of donor support

Military Sexual Trauma Is Associated With Eating Disorders, While Combat Exposure Is Not

ObjectiveThere are strong associations among trauma and eating disorders. However, while trauma and eating disorders are more common among veterans than other populations, there is little information on how military-specific stressors affect eating disorder risk. This study's objective was to determine whether military sexual trauma and combat exposure were independent predictors of eating disorders among women veterans, a high-risk group.MethodParticipants were women age 18-70, using VA medical center services, without psychotic disorders or suicidal ideation (N = 407). We estimated a cross-sectional logistic regression model to predict eating disorders (anorexia, bulimia, binge eating disorder) as a function of military sexual trauma and combat exposure, adjusting for demographic variables.ResultsSixty-six percent of participants reported military sexual trauma, 32% reported combat exposure, and 15% met eating disorder criteria. Mean age was 49 years (SD = 13); 40% were veterans of color. Women reporting military sexual trauma had twice the odds of an eating disorder compared to women who did not (odds ratio [OR]: 2.03; 95% CI [1.03-3.98]). Combat exposure was not associated with eating disorders. Asian race (OR: 3.36; 95% CI [1.26-8.97]) and age (OR: 1.03; 95% CI [1.01-1.06]) were associated with eating disorders.ConclusionsThe high rates of military sexual trauma and eating disorders highlight a need for continued work. Results suggest that it may be useful to focus on women reporting military sexual trauma when implementing eating disorder screening and treatment programs. Given associations among trauma, eating disorders, obesity, and mortality, such efforts could greatly improve veteran health. (PsycINFO Database Recor