A comprehensive, multi-process box-model approach to glacial-interglacial carbon cycling

The canonical question of which physical, chemical or biological mechanisms were responsible for oceanic uptake of atmospheric CO2 during the last glacial is yet unanswered. Insight from paleo proxies has led to a multitude of hypotheses but none so far have been convincingly supported in three dimensional numerical modelling experiments. The processes that influence the CO2 uptake and export production are inter-related and too complex to solve conceptually while complex numerical models are time consuming and expensive to run which severely limits the combinations of mechanisms that can be explored. Instead, an intermediate inverse box model approach is used here in which the whole parameter space is explored. The glacial circulation and biological production states are derived from these using proxies of glacial export production and the need to draw down CO2 into the ocean. We find that circulation patterns which explain glacial observations include reduced Antarctic Bottom Water formation and high latitude mixing and to a lesser extent reduced equatorial upwelling. The proposed mechanism of CO2 uptake by an increase of eddies in the Southern Ocean, leading to a reduced residual circulation, is not supported. Regarding biological mechanisms, an increase in the nutrient utilization in either the equatorial regions or the northern polar latitudes can reduce atmospheric CO2 and satisfy proxies of glacial export production. Consistent with previous studies, CO2 is drawn down more easily through increased productivity in the Antarctic region than the sub-Antarctic, but that violates observations of lower export production there

Defining the anabolic window of opportunity. Is protein intake immediately post resistance exercise critically important for muscle growth?

The anabolic response of muscle to resistance exercise and protein feeding is influenced by multiple factors, including the timing of protein feeding. A common perception is that a 45-60 min post-exercise ‘anabolic window of opportunity' time frame exists, within which dietary protein must be consumed to achieve muscle anabolism (and ultimately muscle growth). In this review, we argue the importance of feeding protein immediately following exercise is not as critical as has been espoused. Indeed, muscle remains responsive to protein ingestion for at least 24 h post-exercise. On the other hand, given that feeding protein immediately post-exercise is unlikely to impair the muscle anabolic response, and could improve it, from a practical standpoint, we recommend athletes and exercisers consume some protein, as a meal or supplement, in the immediate period following resistance exercise

Understanding Antarctica - 50 years of British Scientific Monitoring (1959-2009)

Science has always been at the centre of human endeavour in Antarctica. It is just over 50 years since the International Geophysical Year (1957-58) established many of the long-term research and monitoring programmes now undertaken there. On the 50th anniversary of the signing of the Antarctic Treaty, and on completion of International Polar Year (2007-08), it is timely to reflect on the importance of Antarctic monitoring and look to its future. Over the past 50 years, long-term environmental monitoring by the British Antarctic Survey, part of the Natural Environment Research Council, and UK universities has resulted in many important discoveries, such as the hole in the ozone layer and the rapid melting of glaciers on the Antarctic Peninsula. Research on areas such as climate change and ice-sheet-linked sea-level rise clearly demonstrate the global importance of Antarctic science. As an active collaborator working with scientists from other Antarctic Treaty nations, the UK has achieved more than would have been possible working alone. It is essential to continue to monitor the Antarctic environment, parts of which are warming faster than anywhere else on the planet. There are also areas of science about which we have little understanding and which require new long-term research. These include surveying the deep sea, understanding the causes and effects of ocean acidification in the Southern Ocean and predicting the future of Antarctica’s ice sheets, which play a key role in determining global sea level. This publication presents examples of discoveries by UK scientists that have resulted from long-term environmental monitoring

Carbon Catcher Design Report

Overview. The design of the overall Carbon Catcher project can be separated into four distinct systems, each of which is assigned a specialized committee. The committee names and responsibilities are listed below: Air Mover The overall goal for the Air Mover committee is the design of the turbine assembly. As the overall goal of the project is to collect and separate carbon dioxide from the air, one of the most important parts is to actually get the air to pass through the carbon-catching membrane. Passive air would not give a significant enough yield rate to make the carbon dioxide collection rate impactful, thus air must be sucked through a vacuum/turbine. Membrane The goal of Membrain is to create a membrane that can filter out CO2 through various methods. These methods are limited, due to there being such variety, to certain techniques and membrane material types that have been decided, prior, by the committee. Most membranes will be geared towards utilizing temperature and pressure along with gaseous speed and flow rate. In addition, examining certain treatments, such as regeneration of material, and replacements will be looked into as well, to see how it fares in sustainability. Carbon Storer The Carbon Storer committee will design a store and transport system for fluid CO2 after it is extracted from the atmosphere. Primary considerations include geological solutions, cost-effective materials, and analysis methods to improve overall capacity and efficiency. Additionally, the committee will select an environmentally and economically sustainable method of recycling the captured CO2. PyControl The PyControl committee will design a series of sensors and actuators, which will primarily support the sequestration and pipeline systems present in the Carbon Storer Committee and direct air capture system in Air Mover. The design can be broken into four control layers: Input/Output, Field Controllers, Data, and Supervisory. Goal The overarching goal of Carbon Catcher is to design a cost-effective, scalable atmospheric carbon dioxide removal system that is capable of being deployed in a variety of urban environments and may fit a variety of different customer requirements or requests

Supporting Documentation of Informal Learning and Making from a Distance with Voicethread

This best practices session and paper describes the incorporation of Voicethread as a tool for supporting design documentation of makerspace projects among graduate distance education students in a course on informal learning. All students successfully utilized the tool to present photographic and video evidence of design processes with oral annotations, and received clarifications and feedback from peers. Students reported positive affordances of the tool in terms of marking up slides to communicate particular design decisions, sharing video as proof of successfully completing a particular make project and as exemplars of makers’ problem solving and thinking, documenting a linear process with media evidence as a preferred approach to written documentation for informal settings, and making comparative assessments across peer designs with the ability to question and clarify through interaction. The choice of asynchronous documentation versus synchronous collaboration is considered

On the Impact of Feeding Cost Risk in Aquaculture Valuation and Decision Making

We study the effect of stochastic feeding costs on animal-based commodities with particular focus on aquaculture. More specifically, we use soybean futures to infer on the stochastic behaviour of salmon feed, which we assume to follow a Schwartz-2-factor model. We compare the decision of harvesting salmon using a decision rule assuming either deterministic or stochastic feeding costs, i.e. including feeding cost risk. We identify cases, where accounting for stochastic feeding costs leads to significant improvements as well as cases where deterministic feeding costs are a good enough proxy. Nevertheless, in all of these cases, the newly derived rules show superior performance, while the additional computational costs are negligible. From a methodological point of view, we demonstrate how to use Deep-Neural-Networks to infer on the decision boundary that determines harvesting or continuation, improving on more classical regression-based and curve-fitting methods. To achieve this we use a deep classifier, which not only improves on previous results but also scales well for higher dimensional problems, and in addition mitigates effects due to model uncertainty, which we identify in this article. effects due to model uncertainty, which we identify in this article