Nickel hydrogen low Earth orbit test program update and status

The current status of nickel-hydrogen (NiH2) testing ongong at NWSC, Crane In, and The Aerospace Corporation, El Segundo, Ca are described. The objective of this testing is to develop a database for NiH2 battery use in Low Earth Orbit (LEO) and support applications in Medium Altitude Orbit (MAO). Individual pressure vessel-type cells are being tested. A minimum of 200 cells (3.5 in diameter and 4.5 in diameter) are included in the test, from four U.S. vendors. As of this date (Nov. 18, 1986) approximately 60 cells have completed preliminary testing (acceptance, characterization, and environmental testing) and have gone into life cycling

The Occupational Performance of Student-Athletes Post-Concussion: A Guide for Coaches and Athletic Trainers

Concussions are a rising concern amongst the sports community. Student-athletes with concussions can exhibit deficits in physical, psychosocial, cognitive, and visual-perceptual abilities (Centers for Disease Control, 2019). Occupational therapists are equipped to address the impacts of those deficits to improve occupational engagement and performance but are often overlooked in concussion management teams (Finn, 2019). A concussion management team typically consists of coaches, athletic trainers (ATs), physicians, and sometimes physical therapists, depending on the severity of the concussion. Due to growing concern and continued research, the concussion management team must be current with new information. Coaches and ATs may not keep up with new challenges and may not know how to identify subtle signs of concussions. This guidebook aimed to create a guidebook for coaches and ATs on working with student-athletes with concussions to educate them on concussions, how to treat them, understand symptoms, and more. When creating the guidebook, occupational therapy was rooted in the background by utilizing the Model of Human Occupation (MOHO) and the Cognitive-Behavioral Frame of Reference. The guidebook consists of six chapters that include background on concussions, what occupational therapy is and its role, how to identify, treat, and adapt to concussions, how concussions vary by person and sport, and more. This capstone document comprises five chapters that discuss the background, literature review, proposed methods of creating the guidebook, results, and discussion. This capstone project broadens the understanding of concussions in student-athletes and occupational therapy’s role in the concussion management team. Using this guidebook will increase occupational performance and quality of life (QoL) in student-athletes with concussions.https://soar.usa.edu/otdcapstonesspring2024/1003/thumbnail.jp

Review of The Silent Sex: Gender, Deliberation, and Institutions by Christopher F. Karpowitz and Tali Mendelberg (Princeton, NJ: Princeton University Press, 2014)

Review of The Silent Sex: Gender, Deliberation, and Institutions by Christopher F. Karpowitz and Tali Mendelberg (Princeton, NJ: Princeton University Press, 2014)

Tracking forest phenology and seasonal physiology using digital repeat photography: a critical assessment

Digital repeat photography is becoming widely used for near-surface remote sensing of vegetation. Canopy greenness, which has been used extensively for phenological applications, can be readily quantified from camera images. Important questions remain, however, as to whether the observed changes in canopy greenness are directly related to changes in leaf-level traits, changes in canopy structure, or some combination thereof. We investigated relationships between canopy greenness and various metrics of canopy structure and function, using five years (2008–2012) of automated digital imagery, ground observations of phenological transitions, leaf area index (LAI) measurements, and eddy covariance estimates of gross ecosystem photosynthesis from the Harvard Forest, a temperate deciduous forest in the northeastern United States. Additionally, we sampled canopy sunlit leaves on a weekly basis throughout the growing season of 2011. We measured physiological and morphological traits including leaf size, mass (wet/dry), nitrogen content, chlorophyll fluorescence, and spectral reflectance and characterized individual leaf color with flatbed scanner imagery. Our results show that observed spring and autumn phenological transition dates are well captured by information extracted from digital repeat photography. However, spring development of both LAI and the measured physiological and morphological traits are shown to lag behind spring increases in canopy greenness, which rises very quickly to its maximum value before leaves are even half their final size. Based on the hypothesis that changes in canopy greenness represent the aggregate effect of changes in both leaf-level properties (specifically, leaf color) and changes in canopy structure (specifically, LAI), we developed a two end-member mixing model. With just a single free parameter, the model was able to reproduce the observed seasonal trajectory of canopy greenness. This analysis shows that canopy greenness is relatively insensitive to changes in LAI at high LAI levels, which we further demonstrate by assessing the impact of an ice storm on both LAI and canopy greenness. Our study provides new insights into the mechanisms driving seasonal changes in canopy greenness retrieved from digital camera imagery. The nonlinear relationship between canopy greenness and canopy LAI has important implications both for phenological research applications and for assessing responses of vegetation to disturbances.Organismic and Evolutionary Biolog

Fetal and Early Post-Natal Mineralization of the Tympanic Bulla in Fin Whales May Reveal a Hitherto Undiscovered Evolutionary Trait

The evolution of the cetacean skeleton followed a path that differentiated this group from other terrestrial mammals about 50 million years ago [1], and debate is still going on about the relationships between Cetacea and Artiodactyla [2], [3], [4]. Some skeletal traits of the basilosaurids (the more advanced forms of Archaeocetes), such as the expansion of the peribullary air sinuses, dental modification and vertebral size uniformity [5] are maintained and further emphasized also in contemporary odontocetes and mysticetes. Using Dual-Energy X-Ray Absorptiometry here we report that the deposition of bone mineral in fetal and newborn specimens of the fin whale Balaenoptera physalus is remarkably higher in the bulla tympanica than in the adjacent basal skull or in the rest of the skeleton. Ossification of the tympanic bulla in fetal Artiodactyla (bovine, hippopotamus) is minimal, becomes sensible after birth and then progresses during growth, contrarily to the precocious mineralization that we observed in fin whales. Given the importance of the ear bones for the precise identification of phylogenetic relationship in therian evolution [6], this feature may indicate a specific evolutionary trait of fin whales and possibly other cetacean species or families. Early mineralization of the tympanic bulla allows immediate sound conduction in the aquatic medium and consequently holds potential importance for mother-calf relationship and postnatal survival

Space-filling and benthic competition on coral reefs

Reef-building corals are ecosystem engineers that compete with other benthic organisms for space and resources. Corals harvest energy through their surface by photosynthesis and heterotrophic feeding, and they divert part of this energy to defend their outer colony perimeter against competitors. Here, we hypothesized that corals with a larger space-filling surface and smaller perimeters increase energy gain while reducing the exposure to competitors. This predicted an association between these two geometric properties of corals and the competitive outcome against other benthic organisms. To test the prediction, fifty coral colonies from the Caribbean island of Curaçao were rendered using digital 3D and 2D reconstructions. The surface areas, perimeters, box-counting dimensions (as a proxy of surface and perimeter space-filling), and other geometric properties were extracted and analyzed with respect to the percentage of the perimeter losing or winning against competitors based on the coral tissue apparent growth or damage. The increase in surface space-filling dimension was the only significant single indicator of coral winning outcomes, but the combination of surface space-filling dimension with perimeter length increased the statistical prediction of coral competition outcomes. Corals with larger surface space-filling dimensions (Ds > 2) and smaller perimeters displayed more winning outcomes, confirming the initial hypothesis. We propose that the space-filling property of coral surfaces complemented with other proxies of coral competitiveness, such as life history traits, will provide a more accurate quantitative characterization of coral competition outcomes on coral reefs. This framework also applies to other organisms or ecological systems that rely on complex surfaces to obtain energy for competition