Investigating perennial & annual eelgrass (Zostera marina L.) in Padilla Bay as potential donor sources for seed-based restoration

This paper explores recovery of eelgrass (Zostera marina L.) meadows through seed-based restoration to address declines from natural and anthropogenic disturbances. The study focuses on the Joe Leary meadow site in Padilla Bay, Washington, aiming to (1) determine the spatial distribution of perennial and annual Z. marina, (2) understand variation in flowering shoot density and potential seed production, and (3) compare the phenology of flowering shoots. These objectives were investigated using field-based methods to collect presence/absence transect data for delineation, quadrat-based count data, and monitor seed development. Data collection occurred in the summer throughout the flowering life stage of eelgrass in the site. The study found spatial and temporal variation in the distribution, density, and phenology of flowering perennial and annual populations. Delineation methods revealed that annuals have a similar range in the intertidal as perennials, with differences highlighted in response to potential stress indicators such as proximity to the slough, algal mats, or elevation. Quadrat-based monitoring found annual shoots in the transect higher in the intertidal, above the perennial population. Phenology data indicated that perennial shoots flower about a month prior to annual shoots. While the study advises against using perennial flowering shoots for restoration due to low densities, it emphasizes Joe Leary\u27s potential as a donor site for flowering annuals for seed-based restoration. Careful considerations are crucial to avoid unintended introductions of non-native species. The research concludes with recommendations for refining delineation methods, enhancing understanding of eelgrass population dynamics, and optimizing seed collection strategies for genetically diverse and resilient restoration in the face of climate change

Flight Measurements with the Douglas D-558-II (buaero No. 37974) Research Airplane : Dynamic Lateral Stability

The paper presents flight measurements of the dynamic lateral stability of the D-558-II (BuAero No. 37974) research airplane. Data are presented for a range of calibrated airspeed from 167 miles per hour to 474 miles per hour

Contributions of the dentate gyrus to episodic and spatial memory

Animals learn from past experience to guide future behavior and improve survival. This ability relies in part on specific episodic memories of past events encoded by neuronal activity and stored by updated connectivity between neurons. The unique architecture and activity of the hippocampus and related cortical regions are crucial for supporting these episodic memories. Hippocampal models propose the need for a pattern separation function to disambiguate similar memories and a pattern completion function to recall the full breadth of an experience from a partial cue. Past work suggests that neuronal activity in the dentate gyrus (DG) of hippocampus contributes to memory-guided navigation and plays a role in pattern separation. We tested the role of specific DG neuronal ensembles (i.e. engrams) in supporting the pattern separation function and altering downstream neural activity and, ultimately, behavior. To that end, we used an activity-dependent labeling paradigm to identify and manipulate engram ensembles during navigational and contextual fear conditioning (CFC) tasks. The results of our first experiment revealed that the DG partially disambiguates specific maze trajectories while still exhibiting greater overlap than chance levels. These findings suggest that the DG contributes to memory-guided navigation by both pattern separation and completion. Our second experiment manipulated nonspecific memory-related DG populations to assess the functional role of these cells in task generalization across contexts and ongoing spatial working memory. Optogenetic activation of these ensembles disrupted performance accuracy and exhibited a time-dependent impairment effect suggesting a role of the DG in task generalization between contexts. The final experiments investigated the physiological ramifications of artificial memory ensemble reactivation during ongoing navigation behavior. We recorded local field potential (LFP) and single unit responses in mouse DG and CA1 during artificial reactivation of a DG-mediated CFC memory engram. Stimulation of the DG entrained LFP and individual cell spiking in a subpopulation of CA1 pyramidal cells. Their spatial information was disrupted by stimulation despite stable navigational representation before and after the manipulation. Further, the presence of stimulation could be reliably decoded by the firing rate of the network, suggesting that engram reactivation forced the CA1 to adopt a repeatable state, perhaps to support behavioral expression of memories. In summary, my dissertation work presents empirical and theoretical evidence for the role of the dentate gyrus as a single node of an extended separation/completion circuit distributed anatomically and temporally as a neural mechanism supporting episodic memory

Restoring damaged and declining eelgrass in the San Juan Archipelago: a pioneering program using seeds

The importance of eelgrass (Zostera marina) comes alive through the Coast Salish people’s cultural stories and practices. The presence of these marine flowering plants is important for culturally iconic species such as the Dungeness Crab and Pacific Herring. In the San Juan Archipelago, loss of historical spawning sites for herring appears to coincide with eelgrass decline. In an effort to offset eelgrass decline, the Puget Sound Eelgrass Recovery Strategy outlines a program that includes a plan to “restore and enhance damaged or declining eelgrass beds”. The uprooting and replanting of adult eelgrass plants is commonly used as a restoration technique. However, throughout the range of eelgrass in the Northern Hemisphere the collection and dispersal of eelgrass seeds has been put forward as a low-cost and effective alternative. This technique is proposed because, after pollination, fertilization, and seed development, eelgrass flowering heads disperse a yearly seed rain, and these seeds populate available habitat either within the bed or a distant location. When seeds settle on the ocean floor in suitable conditions, seedlings sprout, and new patches form. In spring 2020, we launched a pilot program at the Friday Harbor Laboratories, University of Washington, to restore eelgrass in the nearshore region of Bell Point in Westcott/Garrison Bays using seeds. In this poster presentation we illustrate a step wise description of our program that includes methods to: 1) estimate seed to ovule ratios to guide flowering head collection; 2) harvest flowering heads while limiting damage to the donor population; 3) capture the season of peak seed release; 4) efficiently gather and store seeds before planting; and 5) deliver seeds to a restoration site. We will also provide an estimate of human hours, supplies and construction materials needed to replicate our program at other sites in the Salish Sea

Demandas energéticas en el bailaor norteamericano profesional de flamenco.

El objetivo de este estudio ha sido examinar la capacidad aeróbica y anaeróbica de bailaores estadounidenses profesionales de flamenco, con el fin de conocer las necesidades energéticas de esta danza. La muestra estudiada estaba formada por 11 bailaores profesionales de flamenco de Albuquerque, Nuevo Méjico (4 hombres y 7 mujeres). Se han registrado 3 variables: la composición corporal, medida con un adipómetro calipers; el consumo máximo de oxígeno (VO2max) estimado mediante el análisis de gases durante un test de esfuerzo progresivo; y la capacidad anaeróbica, calculada a través del test de Wingate. La edad media de los bailaores fue de 28.45 años (22-44 años) y el tiempo medio que llevaban participando en espectáculos flamencos era de 13.5 años (2-40 años). Respecto a la composición corporal, los participantes presentan datos de porcentaje de grasa corporal (GC) inferior a la media, tanto la muestra masculina, 9.96% GC (5,25-13,09% GC), como la femenina, 16.35% GC (12,96-20,17% GC). La media máxima de capacidad aeróbica fue de 51.63 mlO2•kg–1•min–1 para los hombres (40.7-59,5 mlO2•kg–1•min–1) y 38,78 mlO2•kg–1•min–1 para las mujeres (32.9-43,8 mlO2•kg–1•min–1), en ambos casos por encima de la media. La potencia máxima media registrada en el test de Wingate, fue de 16.2 W/kg (13.7-18.3 W/kg) y 11.3 W/kg (8.6 hasta 14.3 W/kg) para hombres y mujeres, respectivamente, con un índice de fatiga del 65.5% (62-74%) para los hombres y 56.1% (35.2-68.1%) para las mujeres. Estos resultados son superiores, casi en un 25 %, a otros datos publicados sobre deportistas que realizan actividades anaeróbicas. Por lo tanto, los bailaores de flamenco tienen una considerable potencia anaeróbica. Atendiendo en los resultados de este estudio, se sugiere que el entrenamiento de bailaores incluya componentes aeróbicos y anaeróbicos

Impact of optogenetic pulse design on CA3 learning and replay: a neural model.

Optogenetic manipulation of hippocampal circuitry is an important tool for investigating learning in vivo. Numerous approaches to pulse design have been employed to elicit desirable circuit and behavioral outcomes. Here, we systematically test the outcome of different single-pulse waveforms in a rate-based model of hippocampal memory function at the level of mnemonic replay extension and de novo synaptic weight formation in CA3 and CA1. Lower-power waveforms with long forward or forward and backward ramps yield more natural sequence replay dynamics and induce synaptic plasticity that allows for more natural memory replay timing, in contrast to square or backward ramps. These differences between waveform shape and amplitude are preserved with the addition of noise in membrane potential, light scattering, and protein expression, improving the potential validity of predictions for in vivo work. These results inform future optogenetic experimental design choices in the field of learning and memory.R01 MH052090 - NIMH NIH HHS; R01 MH060013 - NIMH NIH HHS; R01 MH120073 - NIMH NIH HHS; R01 MH118500 - NIMH NIH HHSPublished versio

A retrospective investigation on age and gender differences of injuries in DanceSport

In spite of the extensive research on incidence site and type of injury in ballet and modern dancers, limited studies on injury in DanceSport have been reported. Therefore, this study determined retrospectively (within last 12 months) incidence, severity, site and type of injury, between gender and age-class in DanceSport. Participants were 97 international sport-dancers (female, 41; male, 56). Sixty-six (69%) dancers reported 96 injuries (1.00 (range = 4)) injuries per dancer) and an injury incidence of 1.7 (range = 14) per 1000 h. Females revealed significantly higher median injury incidence (females, 2.6 (range = 14); males, 1.9 (range = 9), p 0.05) than males. A total of 61.5% of all injuries recorded were traumatic with a significant gender difference (Wald chi-square = 11.616, df = 1, p 0.01). Injury severity was 3 (range 240) days with an interaction effect between gender and age-class (Wald chi-square = 251.374, df = 3, p 0.001). Meanwhile, 72.3% of the dancers reported not including sport specific exercises besides dancing. These findings show gender and age-class differences in injury incidence, type and severity. Therefore, to reduce the likelihood of injuries, the implementation of supplemental DanceSport specific exercises that also considers the gender and age-class anatomical, functional, and choreographic demand differences in the training program should be recognized

Researcher as Artist/Artist as Researcher

This is a postmodern article that is nontraditional in its form, content, and mode of representation. Upon recognizing that we share interests and common experiences as artists, we decided to collect life history information from each other about our artistic experiences. Thus we have become, simultaneously, "the researched" and "the re searcher." In these conversations, we explore the ways in which we were each guided by our past, very strong aesthetic and artistic experiences. We also include the voices of other researchers and artists in our conversations as we explore the influences of art in the formation of our worldviews.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68774/2/10.1177_107780049500100107.pd

Spatiotemporal scaling changes in gait in a progressive model of Parkinson's disease

ObjectiveGait dysfunction is one of the most difficult motor signs to treat in patients with Parkinson's disease (PD). Understanding its pathophysiology and developing more effective therapies for parkinsonian gait dysfunction will require preclinical studies that can quantitatively and objectively assess the spatial and temporal features of gait.DesignWe developed a novel system for measuring volitional, naturalistic gait patterns in non-human primates, and then applied the approach to characterize the progression of parkinsonian gait dysfunction across a sequence of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treatments that allowed for intrasubject comparisons across mild, moderate, and severe stages.ResultsParkinsonian gait dysfunction was characterized across treatment levels by a slower stride speed, increased time in both the stance and swing phase of the stride cycle, and decreased cadence that progressively worsened with overall parkinsonian severity. In contrast, decreased stride length occurred most notably in the moderate to severe parkinsonian state.ConclusionThe results suggest that mild parkinsonism in the primate model of PD starts with temporal gait deficits, whereas spatial gait deficits manifest after reaching a more severe parkinsonian state overall. This study provides important context for preclinical studies in non-human primates studying the neurophysiology of and treatments for parkinsonian gait