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How the Financial Recovery Sacrificed the Middle Class.

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How the Financial Recovery Sacrificed the Middle Class.

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sarcozona
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ARPA-E, a sustainable energy moonshot agency of the US government, is absolutely kicking ass

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The Department of Energy's Advanced Research Projects Agency-Energy [ARPA-E] was set up by bipartisan action in 2007, funded by Obama in 2009; expanded by Congress in 2009; and survived attempts by Trump to kill it in both 2017 and 2018.

ARPA-E is a skunkworks project that gives out grants for advanced sustainable energy research that's beyond the initial phases but still too nascent to be commercialized. They've focused on long-term energy storage (a key piece of the picture with renewables) and the portfolio of inventions that have emerged from their funding is mind-bogglingly cool.

Vox's David Robert runs these down, from the wide variety of thermal storage technologies to the flow batteries, to more exotic ideas like fuel cells and pumped water systems.

Of course, Trump hates the agency, both because it is seen as a creature of the Obama regime and thus must be destroyed, and because it will hasten the demise of fossil fuels.

It’s all in what you heat and how much of the energy you get back out. At Michigan State University, they will heat “a bed of magnesium manganese oxide (Mg-Mn-O) particles.” Brayton Energy, in Hampton, New Hampshire, will heat molten salt. Echogen Power Systems, in Akron, Ohio, will heat “a ‘reservoir’ of low cost materials such as sand or concrete.” The National Renewable Energy Laboratory, in Golden, Colorado, will heat “inexpensive solid particles to temperatures greater than 1100°C” and then get the energy out using “a high performance heat exchanger and closed loop Brayton cycle turbine,” which certainly sounds cool.

Antora Energy, in Fremont, California, will heat “inexpensive carbon blocks” (to 2000° C!). Antora is somewhat unique in that it will get the energy back out not through a turbine, but with “thermophotovoltaic” solar panels “specifically designed to efficiently use the heat radiated by the blocks.”

Thermal storage doesn’t get a lot of press in the energy world — heat is somehow less sexy than electricity — but it has enormous potential to speed decarbonization. It would be awesome to see one of these techs catch on.

A tiny, beleaguered government agency seeks an energy holy grail: long-term energy storage [David Robert/Vox]

(via Naked Capitalism)

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sarcozona
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satadru
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New York, NY
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Bayesian model comparison in ecology

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Conor Goold writes:

I was reading this overview of mixed-effect modeling in ecology, and thought you or your blog readers may be interested in their last conclusion (page 35):

Other modelling approaches such as Bayesian inference are available, and allow much greater flexibility in choice of model structure, error structure and link function. However, the ability to compare among competing models is underdeveloped, and where these tools do exist, they are not yet accessible enough to non-experts to be useful.

This strikes me as quite odd. The paper discusses model selection using information criterion and model averaging in quite some detail, and it is confusing that the authors dismiss the Bayesian analogues (I presume they are aware of DIC, WAIC, LOO etc. [see chapter 7 of BDA3 and this paper — ed.]) as being ‘too hard’ when parts of their article would probably also be too hard for non-experts.

In an area in which small sample sizes are common, I’d argue that effort to explain Bayesian estimation in hierarchical models would have been very worthwhile (e.g. estimation of variance components, more accurate estimation of predictor coefficients using informative priors/variable selection).

In general, I find the ‘Bayesian reasoning is too difficult for non-experts’ argument pretty tiring, especially when it’s thrown in at the end of a paper like this!

Along these lines, I used to get people telling me that I couldn’t use Bayesian methods for applied problems because people wouldn’t stand for it. Au contraire, I’ve used Bayesian methods in many different applied fields for a long time, ever since my first work in political science in the 1980s, and nobody’s ever objected to it. If you don’t want to use some statistical method (Bayesian or otherwise) cos you don’t like it, fine; give your justification and go from there. But don’t ever say not to use a method out of a purported concern that some third party will object. That’s so bogus. Stand behind your own choices.

The post Bayesian model comparison in ecology appeared first on Statistical Modeling, Causal Inference, and Social Science.

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sarcozona
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Eating human food affects wild species’ waistlines, and even their evolution

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As human cities have grown, some wildlife species have figured out how to take advantage of these new habitats. A big plus of city living is the steady stream of easily available, highly calorific, and tasty food – that is, our leftovers. But what happens when animals start to eat like modern humans?

In the case of raccoons, the answer appears to be that they become absolute units. In a study that appears in the August 2018 issue of Conservation Physiology, Canadian researchers weighed and took blood samples from a total of 60 raccoons living in three different areas with varying access to human food [1].

They found that raccoons living on the grounds of the Toronto Zoo – trash panda paradise, with all sorts of tossed-away treats – weigh more and have higher blood sugar than raccoons living in urban parks with moderate access to human food or a rural setting with low access to human food.

The results suggest that the diet that makes us humans fat also makes raccoons fat. However, future research will need to establish more directly whether raccoons with more access to human food actually eat more of it, and whether heavier raccoons have more body fat.

The researchers say that more studies are also needed to determine the evolutionary consequences of these findings. Are raccoons with high blood sugar less likely to survive and reproduce, or more vulnerable to disease? Or are urban raccoons adapting to a junk food diet somehow?

Relatively few studies have investigated the evolutionary consequences for wildlife species of eating human food. Last year, researchers reported that urban white-footed mice have genetic variations associated with metabolism of carbohydrates and lipids that may indicate adaptations for eating our leftovers [2].

A study published 8 August in Proceedings of the Royal Society B suggests something even more dramatic: dietary shifts and the consequent genetic changes may contribute to the emergence of new species. In this study, an international group of researchers sequenced the genomes of 46 house sparrows and 19 Bactrianus sparrows [3].

House sparrows are native to Western and Central Eurasia, but have spread to virtually all inhabited areas of the globe. They live in cities and farmland, and feed on food waste and crops. They are so thoroughly dependent on humans that when people abandon a settlement, house sparrows disappear from the area too.

The Bactrianus sparrow is a house sparrow subspecies that lives in the Middle East and Central Asia, but is not associated with human settlements. It is wary of people and, unlike the house sparrow, migrates. Ornithologists believe the Bactrianus sparrow represents a relict lineage with ancestral characteristics from before the house sparrow became adapted to living alongside humans.

A comparison of the Bactrianus and house sparrow genomes supports the view that the two lineages split 11,000 years ago, around the time agriculture emerged in the Near East. It also suggests that the house sparrow population expanded dramatically about 6,000 years ago. “Commensal house sparrows therefore likely moved into Europe with the spread of agriculture,” the researchers write.

The comparison also identified several genome regions that appear to be involved in the house sparrow’s adaptation to the human niche. The strongest of these regions contains a gene, COL11A, that is involved in skull and facial development. This could help explain how the house sparrow developed a more robust skull and beak compared to the Bactrianus sparrow – an adaptation for eating crop seeds, rather than the softer seeds of wild grasses.

Another gene in the region is AMY2A, which encodes an enzyme involved in digesting starch. Other research has shown that changes in this gene went along with adaptation to high-starch diets in both humans and dogs.

“Our findings therefore add to the emerging picture that the Neolithic revolution introduced a common selective pressure that has resulted in parallel adaptations in similar genes for three very different taxa—humans, dogs and potentially, house sparrows,” the researchers write. That’s more evidence that when we talk about urban dwellers, we’re really talking about a taxonomically diverse menagerie, with a lot of physiological and genetic commonalities across species.

Sources:

  1. Schulte-Hostedde A.I. et al.Enhanced access to anthropogenic food waste is related to hyperglycemia in raccoons (Procyon lotor).” Conservation Physiology. 2018.
  2. Harris J.E. and J. Munshi-South “Signatures of positive selection and local adaptation to urbanization in white-footed mice (Peromyscus leucopus).” Molecular Ecology. 2017
  3. Ravinet M. et al.Signatures of human commensalism in the house sparrow genome.” Proceedings of the Royal Society B. 2018

Image: A raccoon named Rocket eating a cookie. Credit: Tjflex2 via Flickr.



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sarcozona
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Norbert’s gambit.

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Norbert’s gambit.

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When the Grass Isn’t Greener

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From Michael Mortensen:

What’s with all the plastic grass these days in the downtown core? I understand it’s hard to keep stuff alive on these little median strips … put plastic grass? Really? Don’t we have enough plastic in our environment already?

These green edges are quite important in creating a liveable downtown. For all their (our) sophistication, Homo Sapiens Sapiens (literally ‘the apes who know they know’) are still grassland savannah animals; 80% visual; adore green plants.

The sight, sound, fragrance, movement and touch of real landscape and trees soften the city’s concrete edges and obscure towers from our pedestrian vantage. Their movement and colour tell us daily about the weather and changing seasons. Let’s do away with plastic grass at the same time we abandon plastic straws and containers.

 

From Gord Price:

When Council was rezoning for Downtown South – the neighbourhoods between Burrard Street and Yaletown, south of Robson – I, as a councillor from the West End, insisted that as part of the urban-design guidelines for the streetscapes, we include ‘boulevards,’ those planting strips next to the curbs.  After all, if we have had them in the West End since the 19th century, we should have them in the newly adjacent residential neighbourhoods.

I still think it was a good idea, not only for aesthetics but to provide more permeable landscape to deal with surface run-off.  But it quickly became apparent that, particularly where there were parking meters on heavily used commercial streets, the grass would turn to mud.  The responses were varied: some provided stepping stones, some completely filled in the boulevard with asphalt or concrete, some used artificial grass.  Unfortunately, it now seems to be the default surface regardless of circumstances, probably to avoid maintenance as much as to avoid mud.

The best response is to put in more resilient plants, hedges and potted flowers – like this example at Robson and Denman.

Or, more modestly, this one on Homer.

 

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sarcozona
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