1,134 research outputs found

    Consumption-Based Conservation Targeting: Linking Biodiversity Loss to Upstream Demand through a Global Wildlife Footprint.

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    Although most conservation efforts address the direct, local causes of biodiversity loss, effective long-term conservation will require complementary efforts to reduce the upstream economic pressures, such as demands for food and forest products, which ultimately drive these downstream losses. Here, we present a wildlife footprint analysis that links global losses of wild birds to consumer purchases across 57 economic sectors in 129 regions. The United States, India, China, and Brazil have the largest regional wildlife footprints, while per-person footprints are highest in Mongolia, Australia, Botswana, and the United Arab Emirates. A US$100 purchase of bovine meat or rice products occupies approximately 0.1 km2 of wild bird ranges, displacing 1-2 individual birds, for 1 year. Globally significant importer regions, including Japan, the United Kingdom, Germany, Italy, and France, have large footprints that drive wildlife losses elsewhere in the world and represent important targets for consumption-focused conservation attention

    Validating and Verifying Biomathematical Models of Human Fatigue

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    Airline pilots experience acute and chronic sleep deprivation, sleep inertia, and circadian desynchrony due to the need to schedule flight operations around the clock. This sleep loss and circadian desynchrony gives rise to cognitive impairments, reduced vigilance and inconsistent performance. Several biomathematical models, based principally on patterns observed in circadian rhythms and homeostatic drive, have been developed to predict a pilots levels of fatigue or alertness. These models allow for the Federal Aviation Administration (FAA) and commercial airlines to make decisions about pilot capabilities and flight schedules. Although these models have been validated in a laboratory setting, they have not been thoroughly tested in operational environments where uncontrolled factors, such as environmental sleep disrupters, caffeine use and napping, may impact actual pilot alertness and performance. We will compare the predictions of three prominent biomathematical fatigue models (McCauley Model, Harvard Model, and the privately-sold SAFTE-FAST Model) to actual measures of alertness and performance. We collected sleep logs, movement and light recordings, psychomotor vigilance task (PVT), and urinary melatonin (a marker of circadian phase) from 44 pilots in a short-haul commercial airline over one month. We will statistically compare with the model predictions to lapses on the PVT and circadian phase. We will calculate the sensitivity and specificity of each model prediction under different scheduling conditions. Our findings will aid operational decision-makers in determining the reliability of each model under real-world scheduling situations

    Direct Use of Carboxylic Acids in the Photocatalytic Hydroacylation of Styrenes To Generate Dialkyl Ketones

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    A general protocol for the hydroacylation of styrenes from aliphatic carboxylic acids is reported. These reactions proceed via β-scission of a phosphoranyl radical that is accessed by photoredox catalysis, followed by addition of the resulting acyl radical to the styrenyl olefin. We show that phosphine tunability is critical for efficient intermolecular coupling due to competitive quenching of the photocatalyst by the olefin. Primary, secondary, and structurally rigid tertiary carboxylic acids all generate valuable unsymmetrical dialkyl ketones

    They Choose to Attend Academic Summer Camps? A Mixed Methods Study Exploring the Impact of a NASA Academic Summer Pre-Engineering Camp On Middle School Students in a Latino Community

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    Early exposure to engineering and mathematics career opportunities has been indicated to influence students’ decisions regarding their academic majors and career goals. This study utilized mixed methods to analyze how changes in middle school students’ affective characteristics might be linked to their future career decision-making, following participation in an integrated science, technology, engineering, and mathematics summer camp. As part of the summer camp, rising sixth- through eighth-grade students attended a weeklong learning experience based on a specific engineering context. Each grade level cohort participated with their same grade peers in a 36-hour, 6-day event focused on sparking their interest in engineering careers and developing their content knowledge in select science and mathematics content areas. Pre-post testing was conducted with 65 students of diverse backgrounds in grades six through eight to measure their self-reported engineering-related self-efficacy, knowledge of engineering careers, and motivation to pursue future engineering classes and careers. In addition, interviews were conducted to examine any changes in middle school camp participants’ affective characteristics of motivation, self-efficacy, and self-determination

    TP53-inducible Glycolysis and Apoptosis Regulator (TIGAR) Metabolically Reprograms Carcinoma and Stromal Cells in Breast Cancer.

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    A subgroup of breast cancers has several metabolic compartments. The mechanisms by which metabolic compartmentalization develop in tumors are poorly characterized. TP53 inducible glycolysis and apoptosis regulator (TIGAR) is a bisphosphatase that reduces glycolysis and is highly expressed in carcinoma cells in the majority of human breast cancers. Hence we set out to determine the effects of TIGAR expression on breast carcinoma and fibroblast glycolytic phenotype and tumor growth. The overexpression of this bisphosphatase in carcinoma cells induces expression of enzymes and transporters involved in the catabolism of lactate and glutamine. Carcinoma cells overexpressing TIGAR have higher oxygen consumption rates and ATP levels when exposed to glutamine, lactate, or the combination of glutamine and lactate. Coculture of TIGAR overexpressing carcinoma cells and fibroblasts compared with control cocultures induce more pronounced glycolytic differences between carcinoma and fibroblast cells. Carcinoma cells overexpressing TIGAR have reduced glucose uptake and lactate production. Conversely, fibroblasts in coculture with TIGAR overexpressing carcinoma cells induce HIF (hypoxia-inducible factor) activation with increased glucose uptake, increased 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3), and lactate dehydrogenase-A expression. We also studied the effect of this enzyme on tumor growth. TIGAR overexpression in carcinoma cells increases tumor growth in vivo with increased proliferation rates. However, a catalytically inactive variant of TIGAR did not induce tumor growth. Therefore, TIGAR expression in breast carcinoma cells promotes metabolic compartmentalization and tumor growth with a mitochondrial metabolic phenotype with lactate and glutamine catabolism. Targeting TIGAR warrants consideration as a potential therapy for breast cancer

    The Grizzly, November 16, 2023

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    Fantastic Strings Ensemble • Crossword • Celebration of Lights (In Photos) • A Conversation With Ursinus\u27 Archivist, Carolyn Weigel • Food Forest Continues to Grow • The Creative Collegeville Italian Bakery • From Opponent to Family Member: Natalie Mehl\u27s Journey • Ursinus Football Punches Their Ticket to the Postseasonhttps://digitalcommons.ursinus.edu/grizzlynews/2022/thumbnail.jp

    Validation of Fatigue Modeling Predictions in Aviation Operations

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    Bio-mathematical fatigue models that predict levels of alertness and performance are one potential tool for use within integrated fatigue risk management approaches. A number of models have been developed that provide predictions based on acute and chronic sleep loss, circadian desynchronization, and sleep inertia. Some are publicly available and gaining traction in settings such as commercial aviation as a means of evaluating flight crew schedules for potential fatigue-related risks. Yet, most models have not been rigorously evaluated and independently validated for the operations to which they are being applied and many users are not fully aware of the limitations in which model results should be interpreted and applied
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