80 research outputs found
Eddy covariance measurements of the surface energy balance associated with a localised coral bleaching event, Heron Reef, Great Barrier Reef, Australia
While their ecological, economical and societal values are irrefutable, an uncertain future exists for coral reefs and numerous studies suggest that the threat of coral bleaching will worsen under global warming. Despite the association between global warming and coral reef health, there is a paucity of data relating to the exchanges of heat, moisture and momentum between the atmosphere and the reef surface during bleaching episodes. Understanding these key reef-atmosphere interactions is essential for identifying the processes which control the thermal environment of water on the reef. In this paper we present new direct in situ measurements of radiation transfers and sensible and latent heat fluxes associated with an observed localised coral bleaching event at Heron Reef, in the southern Great Barrier Reef. Measurements were made during a three day period in February 2009 using the Eddy Covariance method. Under the influence of a weak barometric pressure gradient, clear skies and light north easterly winds, daily net radiation peaked at more than 800 W m2, with up to 95% of the net radiation during the morning being partitioned into heating the water column, substrate and benthic cover. Heating was exacerbated by a midafternoon low tide, and low wind speeds resulted in reduced evaporative cooling of the water surface. As a result, daily maximum water surface temperatures exceeded 34°C and near-bottom temperatures 33°C. Such conditions in conjunction with limited horizontal heat transfer due to the pooling of reef waters at the site meant that the water surface and near-bottom water temperatures exceeded 30°C for 27% and 38% of the duration of the observation period respectively resulting in widespread coral bleaching
Spatial heterogeneity of air-sea energy fluxes over a coral reef-Heron Reef, Australia
The thermal environment of a coral reef is moderated by complex interactions of air-sea heat and moisture fluxes, local to synoptic-scale weather and reef hydrodynamics. Measurements of air-sea energy fluxes over coral reefs are essential to understanding the reef-atmosphere processes that underpin coral reef environmental conditions such as water temperature, cloud, precipitation, and local winds (such as during coral bleaching events). Such measurements over coral reefs have been rare, however, and the spatial heterogeneity of surface-atmosphere energy exchanges due to the different geomorphic and biological zones on coral reefs has not been captured. Accordingly, the heterogeneity of coral reefs with regard to substrate, benthic communities, and hydrodynamic processes has not been considered in the characterization of the surface radiation budget and energy balance of coral reefs. Here, the first concurrent in situ eddy covariance measurements of the surface energy balance and radiation transfers over different geomorphic zones of a coral reef are presented. Results showed differences in radiation transfers and sensible and latent heat fluxes over the reef, with higher Bowen ratios over the shallow reef flat zone. The energy flux divergence between sites increased with wind speed and during unstable, southeasterly trade winds with the net flux of heat being positive and negative over different geomorphic zones. The surface drag coefficient at measurement height ranged from 1 x 10(-3) to 2.5 x 10(-3), with no significant difference between sites. Results confirm that spatial variation in radiation and air-reef-water surface heat and moisture fluxes occurs across a lagoonal platform reef in response to local meteorological conditions, hydrodynamics, and benthic-substrate cover
Position Paper: Designing Complex Systems to Support Interdisciplinary Cognitive Work
The paper argues that the field we can call cognitive science of interdisciplinary collaboration is an important area of study for improving design of Large-Scale Complex Systems (LaCES) and supporting cognitive work. The paper mostly raised questions that have been documented in earlier qualitative analysis studies, and provided possible avenues of exploration for addressing them. There are likely further contributions from additional disciplines beyond those mentioned in this paper that should be considered and integrated into such a cognitive science framework. Knowledge and awareness of various perspectives will help to inform the types of interventions available for improving LaCES design and functionality. For example, a cognitive interpretation of interdisciplinary collaborations in LaCES elucidated the need for a "translator" or "mediator" in helping subject matter experts to transcend language boundaries, mitigate single discipline bias, support integrative activities, and correct misaligned objectives. Additional research in this direction is likely to uncover similar gaps and opportunities for improvements in practice
Katalyst Pilot Study: Using Interactive Activities in Anatomy and Physiology to Teach Children the Scientific Foundations of Healthy Lifestyles
Analysis of eligibility criteria in Alzheimer’s and related dementias clinical trials
Overly restrictive clinical trial eligibility criteria can reduce generalizability, slow enrollment, and disproportionately exclude historically underrepresented populations. The eligibility criteria for 196 Alzheimer’s Disease and Related Dementias (AD/ADRD) trials funded by the National Institute on Aging were analyzed to identify common criteria and their potential to disproportionately exclude participants by race/ethnicity. The trials were categorized by type (48 Phase I/II pharmacological, 7 Phase III/IV pharmacological, 128 non-pharmacological, 7 diagnostic, and 6 neuropsychiatric) and target population (51 AD/ADRD, 58 Mild Cognitive Impairment, 25 at-risk, and 62 cognitively normal). Eligibility criteria were coded into the following categories: Medical, Neurologic, Psychiatric, and Procedural. A literature search was conducted to describe the prevalence of disparities for eligibility criteria for African Americans/Black (AA/B), Hispanic/Latino (H/L), American Indian/Alaska Native (AI/AN) and Native Hawaiian/Pacific Islander (NH/PI) populations. The trials had a median of 15 criteria. The most frequent criterion were age cutoffs (87% of trials), specified neurologic (65%), and psychiatric disorders (61%). Underrepresented groups could be disproportionately excluded by 16 eligibility categories; 42% of trials specified English-speakers only in their criteria. Most trials (82%) contain poorly operationalized criteria (i.e., criteria not well defined that can have multiple interpretations/means of implementation) and criteria that may reduce racial/ethnic enrollment diversity.</p
Aquatic Invasions: Causes, Consequences, And Solutions
Invasive species represent a global threat to ecosystems, human health, and the economy. A basic knowledge of invasive species biology is crucial to understand current and future impacts and implications. The purpose of this book is to provide a broad background on invasive species, and also details on specific examples through case studies.
The students in the course Aquatic Invasive Species (MAR 442) at the University of New England in Biddeford, Maine, have researched and reviewed scientific literature to educate readers about these issues. The class, comprised of twelve junior and senior Marine Science, Marine Affairs, Applied Mathematics, and Environmental Sciences students, selected the different topics, presented the material, wrote the chapters, and assembled the final versions into this book. This book cannot be all inclusive, but we think this book will provide an excellent broad overview of the most important aspects of Invasive Species Biology and might stimulate the reader to dive deeper into the material.https://dune.une.edu/marinesci_studproj/1002/thumbnail.jp
Increased insulin sensitivity and diminished pancreatic beta-cell function in DNA repair deficient Ercc1(d/-) mice
Background: Type 2 diabetes (T2DM) is an age-associated disease characterized by hyperglycemia due to insulin resistance and decreased beta-cell function. DNA damage accumulation has been associated with T2DM, but whether DNA damage plays a role in the pathogenesis of the disease is unclear. Here, we used mice deficient for the DNA excision-repair gene Ercc1 to study the impact of persistent endogenous DNA damage accumulation on energy metabolism, glucose homeostasis and beta-cell function. Methods: ERCC1-XPF is an endonuclease required for multiple DNA repair pathways and reduced expression of ERCC1-XPF causes accelerated accumulation of unrepaired endogenous DNA damage and accelerated aging in humans andmice. In this study, energy metabolism, glucose metabolism, beta-cell function and insulin sensitivity were studied in Ercc1(d/-) mice, which model a human progeroid syndrome. Results: Ercc1(d/-) mice displayed suppression of the somatotropic axis and altered energy metabolism. Insulin sensitivitywas increased, whereas, plasma insulin levelswere decreased in Ercc1(d/-) mice. Fasting induced hypoglycemia in Ercc1(d/-) mice, whichwas the result of increased glucose disposal. Ercc1(d/-) mice exhibit a significantly reduced beta-cell area, even compared to control mice of similar weight. Glucose-stimulated insulin secretion in vivo was decreased in Ercc1(d/-) mice. Islets isolated from Ercc1(d/-) mice showed increased DNA damage markers, decreased glucose-stimulated insulin secretion and increased susceptibility to apoptosis. Conclusion: Spontaneous DNA damage accumulation triggers an adaptive response resulting in improved insulin sensitivity. Loss of DNA repair, however, does negatively impacts beta-cell survival and function in Ercc1(d/-) mice. (C) 2021 The Author(s). Published by Elsevier Inc
An analysis of the efficacy of low-scale concentrated photovoltaics
Gemstone Team LEAF (Light Energy Acquisition of the Future)The plausibility of low-concentrating flat-plate photovoltaics as a viable
small-scale energy generation system was explored. A flat-plate photovoltaic panel
utilizing an inexpensive parabolic reflector to increase the solar radiation incident on
the panel was constructed. The concentration system's performance was compared to a solitary flat-plate photovoltaic panel with no concentration. The concentrating panel
experienced a maximum of seven times and averaged three to four times the power
output of the flat system. It is projected that similar systems could provide a less
costly alternative to consumer scale solar panels that use expensive efficiency-increasing tracking systems
Epidemiology of Exertional Rhabdomyolysis Susceptibility in Standardbred Horses Reveals Associated Risk Factors and Underlying Enhanced Performance
BACKGROUND: Exertional rhabdomyolysis syndrome is recognised in many athletic horse breeds and in recent years specific forms of the syndrome have been identified. However, although Standardbred horses are used worldwide for racing, there is a paucity of information about the epidemiological and performance-related aspects of the syndrome in this breed. The objectives of this study therefore were to determine the incidence, risk factors and performance effects of exertional rhabdomyolysis syndrome in Standardbred trotters and to compare the epidemiology and genetics of the syndrome with that in other breeds. METHODOLOGY/PRINCIPAL FINDINGS: A questionnaire-based case-control study (with analysis of online race records) was conducted following identification of horses that were determined susceptible to exertional rhabdomyolysis (based on serum biochemistry) from a total of 683 horses in 22 yards. Thirty six exertional rhabdomyolysis-susceptible horses were subsequently genotyped for the skeletal muscle glycogen synthase (GYS1) mutation responsible for type 1 polysaccharide storage myopathy. A total of 44 susceptible horses was reported, resulting in an annual incidence of 6.4 (95% CI 4.6-8.2%) per 100 horses. Female horses were at significantly greater risk than males (odds ratio 7.1; 95% CI 2.1-23.4; p = 0.001) and nervous horses were at a greater risk than horses with calm or average temperaments (odds ratio 7.9; 95% CI 2.3-27.0; p = 0.001). Rhabdomyolysis-susceptible cases performed better from standstill starts (p = 0.04) than controls and had a higher percentage of wins (p = 0.006). All exertional rhabdomyolysis-susceptible horses tested were negative for the R309H GYS1 mutation. CONCLUSIONS/SIGNIFICANCE: Exertional rhabdomyolysis syndrome in Standardbred horses has a similar incidence and risk factors to the syndrome in Thoroughbred horses. If the disorder has a genetic basis in Standardbreds, improved performance in susceptible animals may be responsible for maintenance of the disorder in the population
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