Regional Variability and Drivers of Below Ice CO2 in Boreal and Subarctic Lakes

Northern lakes are ice-covered for considerable portions of the year, where carbon dioxide (CO2) can accumulate below ice, subsequently leading to high CO2 emissions at ice-melt. Current knowledge on the regional control and variability of below ice partial pressure of carbon dioxide (pCO(2)) is lacking, creating a gap in our understanding of how ice cover dynamics affect the CO2 accumulation below ice and therefore CO2 emissions from inland waters during the ice-melt period. To narrow this gap, we identified the drivers of below ice pCO(2) variation across 506 Swedish and Finnish lakes using water chemistry, lake morphometry, catchment characteristics, lake position, and climate variables. We found that lake depth and trophic status were the most important variables explaining variations in below ice pCO(2) across the 506 lakes(.) Together, lake morphometry and water chemistry explained 53% of the site-to-site variation in below ice pCO(2). Regional climate (including ice cover duration) and latitude only explained 7% of the variation in below ice pCO(2). Thus, our results suggest that on a regional scale a shortening of the ice cover period on lakes may not directly affect the accumulation of CO2 below ice but rather indirectly through increased mobility of nutrients and carbon loading to lakes. Thus, given that climate-induced changes are most evident in northern ecosystems, adequately predicting the consequences of a changing climate on future CO2 emission estimates from northern lakes involves monitoring changes not only to ice cover but also to changes in the trophic status of lakes.Peer reviewe

[Review of] Jamake Highwater. The Sun, He Dies

How do we ever own our history? How do we ever come to grips with our fairy tales of that history? How do we ever rationalize genocide? The Sun, He Dies makes us ask. Aztec Mexico is presented with its intricacies and intrigues, dreams and realities in this fictional piece based on folk history and historical documents. Nanuatzin, the woodcutter, is the invented character who ties the events together and presents this alternative view of history that we must face. In the Afterward and Notes on Sources, Highwater states, History is always the account of events as seen and preserved by the dominant culture . .. The Sun, He Dies is an alternative vision of the same history. It is a painful vision from two standpoints: one, to own the greed, not grace, which prompted Cortes, and two, to examine the conflicting personal state of Montezuma and his impact on Aztec life and history

Symptom biology and accelerated aging in heart failure

Heart failure (HF) is the fastest growing cardiovascular condition in the United States, and along with the growth of the elderly population, the number of adults affected by HF will increase both nation- and worldwide. To those individuals affected by HF, this condition confers enormous symptom burden, severe functional limitations, and reduced quality of life. Despite the importance of symptom burden in HF, however, there is a limited understanding of the biological underpinnings of symptoms in HF, including how accelerated biological aging intersects with symptoms. The purpose of this program of research was to elucidate the biological underpinnings of symptoms among adults with HF, particularly the role of accelerated biological aging in explaining symptoms in HF

Gender and Videogames: The political valency of Lara Croft

The Face: Is Lara a feminist icon or a sexist fantasy? Toby Gard: Neither and a bit of both. Lara was designed to be a tough, self-reliant, intelligent woman. She confounds all the sexist cliches apart from the fact that she’s got an unbelievable figure. Strong, independent women are the perfect fantasy girls—the untouchable is always the most desirable (Interview with Lara’s creator Toby Gard in The Face magazine, June 1997)

Summer CO2 evasion from streams and rivers in the Kolyma River basin, north-east Siberia

Inland water systems are generally supersaturated in carbon dioxide (CO2) and are increasingly recognized as playing an important role in the global carbon cycle. The Arctic may be particularly important in this respect, given the abundance of inland waters and carbon contained in Arctic soils; however, a lack of trace gas measurements from small streams in the Arctic currently limits this understanding.We investigated the spatial variability of CO2 evasion during the summer low-flow period from streams and rivers in the northern portion of the Kolyma River basin in north-eastern Siberia. To this end, partial pressure of carbon dioxide (pCO2) and gas exchange velocities (k) were measured at a diverse set of streams and rivers to calculate CO2 evasion fluxes. We combined these CO2 evasion estimates with satellite remote sensing and geographic information system techniques to calculate total areal CO2 emissions. Our results show that small streams are substantial sources of atmospheric CO2 owing to high pCO2 and k, despite being a small portion of total inland water surface area. In contrast, large rivers were generally near equilibrium with atmospheric CO2. Extrapolating our findings across the Panteleikha-Ambolikha sub-watersheds demonstrated that small streams play a major role in CO2 evasion, accounting for 86% of the total summer CO2 emissions from inland waters within these two sub-watersheds. Further expansion of these regional CO2 emission estimates across time and space will be critical to accurately quantify and understand the role of Arctic streams and rivers in the global carbon budget

plugfinder.com: Finding and Sharing Electricity in Your City

The proliferation of mobile electronic technology such as cellular phones, laptops, and lightweight video projectors increases the demand for electrical outlets in public and semi-public spaces. www.plugfinder.com is a website that allows people to annotate maps of electricity outlets in their city. The virtual activity that takes place on the website is accompanied by occasional organized walking tours by the plugfinder team. plugfinder.com is a project that promotes the temporary use of urban spaces through the creative adaptation of electrical infrastructure. By documenting and facilitating street level uses of electricity, the plugfinder project calls attention to the manner in which daily routines and access to resources are defined by infrastructure, bringing to light a little noticed, yet vital, public resource. This paper posits that providing electricity as a public good has the potential to generate social and cultural capital for cities. This document may be relevant to municipal governments, urban planners or economists in order to prepare for creative uses of electrical infrastructure. The plugfinder.com project itself may be relevant to anyone who wants to explore or use space temporarily in the city they inhabit.Master of Fine Arts (MFA)http://deepblue.lib.umich.edu/bitstream/2027.42/55457/1/zack_denfeld_thesis_plugfinder.pd

Teacher identity in work with students' psychosocial environment: A systematic review of quantitative research

This article is a contribution to understanding teacher identity related to working with students' psychosocial environment (PSE). A systematic review of quantitative studies (n = 10) analyzing the relations between components of teacher identity and teachers' work with the PSE is presented. Findings indicate significant relations between the identity components task-related self-efficacy and job satisfaction along with likelihood or frequency of intervention in bullying situations. However, results regarding relations between general teaching efficacy or task perception and teachers' approach to bullying were inconclusive. Findings suggest that teachers' self-efficacy and job satisfaction as identity domains play an important role in students' PSE. This information has implications for teacher education, professional development, and policymakers.publishedVersio