288 research outputs found
Effects of Human Choices on Characteristics of Urban Ecosystems
Most urban ecology in cities remains an ecology in cities rather than an ecology of cities. Accomplishing the latter requires the inclusion of humans within the concept of ecosystem, both how humans alter the properties of urban ecosystems and how these alterations in turn influence human well-being. These influences are both direct (e.g., physiological and psychological influences on the human organism) and indirect, by influencing ecosystem sustainability. For the 2007 ESA meeting, Larry Baker, Loren Byrne, Jason Walker, and Alex Felson organized a symposium to address the relationships among human choices and urban ecosystems. In the introductory talk of this symposium, these authors discussed how the cumulative effect of individual household choices can have major effects on the properties of urban ecosystems
Insulin Tolerance Test under Anaesthesia to Measure Tissue-specific Insulin-stimulated Glucose Disposal.
Insulin resistance is a pathophysiological state defined by impaired responses to insulin and is a risk factor for several metabolic diseases, most notably type 2 diabetes. Insulin resistance occurs in insulin target tissues including liver, adipose and skeletal muscle. Methods such as insulin tolerance tests and hyperinsulinaemic-euglycaemic clamps permit assessment of insulin responses in specific tissues and allow the study of the progression and causes of insulin resistance. Here we detail a protocol for assessing insulin action in adipose and muscle tissues in anesthetized mice administered with insulin intravenously
Ecological homogenization of oil Properties in the American Residential Macrosystem
The conversion of native ecosystems to residential ecosystems dominated by lawns has been a prevailing land-use change in the United States over the past 70 years. Similar development patterns and management of residential ecosystems cause many characteristics of residential ecosystems to be more similar to each other across broad continental gradients than that of former native ecosystems. For instance, similar lawn management by irrigation and fertilizer applications has the potential to influence soil carbon (C) and nitrogen (N) pools and processes. We evaluated the mean and variability of total soil C and N stocks, potential net N mineralization and nitrification, soil nitrite (NO2−)/nitrate (NO3−) and ammonium (NH4+) pools, microbial biomass C and N content, microbial respiration, bulk density, soil pH, and moisture content in residential lawns and native ecosystems in six metropolitan areas across a broad climatic gradient in the United States: Baltimore, MD (BAL); Boston, MA (BOS); Los Angeles, CA (LAX); Miami, FL (MIA); Minneapolis–St. Paul, MN (MSP); and Phoenix, AZ (PHX). We observed evidence of higher N cycling in lawn soils, including significant increases in soil NO2−/NO3−, microbial N pools, and potential net nitrification, and significant decreases in NH4+ pools. Self-reported yard fertilizer application in the previous year was linked with increased NO2−/ NO3− content and decreases in total soil N and C content. Self-reported irrigation in the previous year was associated with decreases in potential net mineralization and potential net nitrification and with increases in bulk density and pH. Residential topsoil had higher total soil C than native topsoil, and microbial biomass C was markedly higher in residential topsoil in the two driest cities (LAX and PHX). Coefficients of variation for most biogeochemical metrics were higher in native soils than in residential soils across all cities, suggesting that residential development homogenizes soil properties and processes at the continental scale
iPSCORE: A Resource of 222 iPSC Lines Enabling Functional Characterization of Genetic Variation across a Variety of Cell Types.
Large-scale collections of induced pluripotent stem cells (iPSCs) could serve as powerful model systems for examining how genetic variation affects biology and disease. Here we describe the iPSCORE resource: a collection of systematically derived and characterized iPSC lines from 222 ethnically diverse individuals that allows for both familial and association-based genetic studies. iPSCORE lines are pluripotent with high genomic integrity (no or low numbers of somatic copy-number variants) as determined using high-throughput RNA-sequencing and genotyping arrays, respectively. Using iPSCs from a family of individuals, we show that iPSC-derived cardiomyocytes demonstrate gene expression patterns that cluster by genetic background, and can be used to examine variants associated with physiological and disease phenotypes. The iPSCORE collection contains representative individuals for risk and non-risk alleles for 95% of SNPs associated with human phenotypes through genome-wide association studies. Our study demonstrates the utility of iPSCORE for examining how genetic variants influence molecular and physiological traits in iPSCs and derived cell lines
Insulin signaling requires glucose to promote lipid anabolism in adipocytes
Adipose tissue is essential for metabolic homeostasis, balancing lipid storage and mobilization based on nutritional status. This is coordinated by insulin, which triggers kinase signaling cascades to modulate numerous metabolic proteins, leading to increased glucose uptake and anabolic processes like lipogenesis. Given recent evidence that glucose is dispensable for adipocyte respiration, we sought to test whether glucose is necessary for insulin-stimulated anabolism. Examining lipogenesis in cultured adipocytes, glucose was essential for insulin to stimulate the synthesis of fatty acids and glyceride–glycerol. Importantly, glucose was dispensable for lipogenesis in the absence of insulin, suggesting that distinct carbon sources are used with or without insulin. Metabolic tracing studies revealed that glucose was required for insulin to stimulate pathways providing carbon substrate, NADPH, and glycerol 3-phosphate for lipid synthesis and storage. Glucose also displaced leucine as a lipogenic substrate and was necessary to suppress fatty acid oxidation. Together, glucose provided substrates and metabolic control for insulin to promote lipogenesis in adipocytes. This contrasted with the suppression of lipolysis by insulin signaling, which occurred independently of glucose. Given previous observations that signal transduction acts primarily before glucose uptake in adipocytes, these data are consistent with a model whereby insulin initially utilizes protein phosphorylation to stimulate lipid anabolism, which is sustained by subsequent glucose metabolism. Consequently, lipid abundance was sensitive to glucose availability, both during adipogenesis and in Drosophila flies in vivo. Together, these data highlight the importance of glucose metabolism to support insulin action, providing a complementary regulatory mechanism to signal transduction to stimulate adipose anabolism
Homogenization of Plant Diversity, Composition, and Structure in North American Urban Yards
Urban ecosystems are widely hypothesized to be more ecologically homogeneous than natural ecosystems. We argue that urban plant communities assemble from a complex mix of horticultural and regional species pools, and evaluate the homogenization hypothesis by comparing cultivated and spontaneously occurring urban vegetation to natural area vegetation across seven major U.S. cities. There was limited support for homogenization of urban diversity, as the cultivated and spontaneous yard flora had greater numbers of species than natural areas, and cultivated phylogenetic diversity was also greater. However, urban yards showed evidence of homogenization of composition and structure. Yards were compositionally more similar across regions than were natural areas, and tree density was less variable in yards than in comparable natural areas. This homogenization of biodiversity likely reflects similar horticultural source pools, homeowner preferences, and management practices across U.S. cities
Continental-scale homogenization of residential lawn plant communities
© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Landscape and Urban Planning 165 (2017): 54-63, doi:10.1016/j.landurbplan.2017.05.004.Residential lawns are highly managed ecosystems that occur in urbanized landscapes across the United States. Because they are ubiquitous, lawns are good systems in which to study the potential homogenizing effects of urban land use and management together with the continental-scale effects of climate on ecosystem structure and functioning. We hypothesized that similar homeowner preferences and management in residential areas across the United States would lead to low plant species diversity in lawns and relatively homogeneous vegetation across broad geographical regions. We also hypothesized that lawn plant species richness would increase with regional temperature and precipitation due to the presence of spontaneous, weedy vegetation, but would decrease with household income and fertilizer use. To test these predictions, we compared plant species composition and richness in residential lawns in seven U.S. metropolitan regions. We also compared species composition in lawns with understory vegetation in minimally-managed reference areas in each city. As expected, the composition of cultivated turfgrasses was more similar among lawns than among reference areas, but this pattern also held among spontaneous species. Plant species richness and diversity varied more among lawns than among reference areas, and more diverse lawns occurred in metropolitan areas with higher precipitation. Native forb diversity increased with precipitation and decreased with income, driving overall lawn diversity trends with these predictors as well. Our results showed that both management and regional climate shaped lawn species composition, but the overall homogeneity of species regardless of regional context strongly suggested that management was a more important driver.This research was supported by the Macrosystems Biology Program in the Emerging Frontiers Division of the Biological Sciences Directorate at the National Science Foundation (NSF) under grants EF-1065548, 1065737, 1065740, 1065741, 1065772, 1065785, 1065831, and 121238320
Volume 09
Introduction Dr. Roger A. Byrne
Islamic Radicalization of Women in The United Kingdom by Mackenzie Adamson
Harmony by Chad Benton
The Rhetoric of Distrust: A Dangerous Game During the 2016 Presidential Campaign by Garrett Badgley
Neither Man nor Monster: Frankenstein\u27s Creature as Posthuman by Anna Bultrowicz
Holisticrx by Kelsey Daniel
Reality Bytes: Identity in the Virtual World of Ernest Cline\u27s Ready Player One by Taylor Embrey
Animation by Jose Romero
Sue Klebold\u27s a Mother\u27s Reckoning: A Call to Action for Mental Health Advocacy by Taylor Hughes
Hillary Clinton\u27s Rhetoric of Gender Inequality: The Past, the Present, nd the (Hypothetical) Future by Haley Klepatzki
Against the Grain: Eat Gluten Free by Emily Spittle
Following Judith: A Midrashic Approach to the Book of Judith by Kelsey Longnaker
Identity and Dialect Adaptation: The Effect of Geography and Community on Dialect by Alexis Paige Manuel
These are the Gardens Of The Desert : The Revolutionary Impact Of Bryant\u27s The Prairies on American Literature by Montana Nelson
Beauty is Pain: Eating Disorders, Gender, and the Lies We Feed Young Women By Faith Shelton
Be a Man: The Eradication of Gender in Y: The Last Man by Joseph Stearman
A Computational Study of Molecular Electronics: The Role of Molecular Structure by John Brumfield
The Importance of Voting by Monica Mcgraw
Method for The Detection and Removal of Antibiotics in Bottled Water by Jayden Metzger
Small Chimp Print by Maddie Smith
Mental Health Impairments in Rural Communities by Lyndsey Swinhart
F@#* That: The Effects of Swearing and Influence of Authority on Stress Level by Amanda N. Chappell And Haley C. Moore
Friend or Faux? Prosocial and Antisocial Social Media Use and Personality Traits by Samantha Burgess, Heather Dunbar, Briana Hackett, Jackie Mcmillion, Kiana Simpkins, And Ta\u27miya Vanhook-Davis
There\u27s Someone in My Head but It’s Not Me : Attitudes About Diagnosis and Treatment of Psychological Disorders by Kiana Simpkins, Lindsey Sparrock, And Leonie Verstraete
Efflorescent Bonds by Kristen Melton
Shower Thoughts by Ryan Bultrowic
Volume 06
Introduction from Dean Dr. Charles Ross
Caught Between Folklore and the Cold War: The Americanization of Russian Children\u27s Literature by Kristen Gains
Graphic Design by Amanda Willis
Graphic Design by Holly Backer
Prejudices in Swiss German Accents by Monika Gutierrez
Photography by Cara O\u27Neal
Photography by Sara Nelson
Edmund Tyrone\u27s Long Journey through Night by Sasha Silberman
Photography by Jessica Beardsley
Photography by Jamie Gardner and Edward Peeples
The Republican Razor: The Guillotine as a Symbol of Equality by Jamie Clift
Graphic Design by Matthew Sakach
Genocide: The Lasting Effects of Gender Stratification in Rwanda By Tess Lione and Emily Wilkins
Photography by Kelsey Holt and Jessica Page
Morocco and the 20 February Movement by Charles Vancampen, Gilbert Hall, Jenny Nehrt, Kasey Dye, Amanda Tharp, Jamie Leeawrik, & Ashley McGee
Photography by Emily Poulin
Photography by Michael Kropf
Improving Performance of Arbitrary Precision Arithmetic Using SIMD Assembly Code Instructions by Nick Pastore
Art by Austin Polasky and Morgan Glasco
Art by Laura L. Kahler
The Effects of the Neutral Response Option on the Extremeness of Participant Responses by Melinda L. Edwards and Brandon C. Smith
Graphic Design by Mariah Asbell
Graphic Design by Cabell Edmunds
College Bullying: An Exploratory Analysis by Amelia D. Perry
Photography by Alyssa Hayes
Death-Related Crime: Applying Bryant\u27s Conceptual Paradigm of Thanatological Crime to Military Settings by Irina Boothe
Graphic Design by Perry Bason
Graphic Design by James Earl
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