Tag: images

PURLs

PURLs are only as good as the maintenance work that has gone into updating the underlying URLs when they inevitably change. And in the lucky cases where the underlying URL haven’t changed, all the work that has gone into managing the infrastructure behind that URL namespace in order for that URL to stay the same. how many of the PURLs still work? This is complex enough for an actual research project and not just a quick blog. Over in the notebook I started by sampling all the target URLs (N=405637 n=662). In the process I noticed that it was oversampling some domains quite a bit like my.yoolib.net. So I tried again, but instead of sampling all the URLs I sampled the PURL namespaces (N=21894, n=644) and picked a random URL from each PURL namespace. This seemed to work better but still seemed to oversample, with hostnames list http://www.olemiss.edu showing up quite a bit. It looks like they might create a new PURL namespace for every finding aid they put up.

Of course, testing whether a URL still works is surprisingly tricky business: the response could be 200 OK but say Not Found, or it could be a totally different page (content drift)

Agrivoltaics

Using vertically mounted bifacial modules allows for more arable land. And if you don’t know what bifacial solar panels are, they can collect solar energy from both sides of the panel. This type of installation would work particularly well in areas that suffer from wind erosion, since the structures reduce wind speeds which can help protect the land and crops grown there. The bifacial panels also can generate more power per square meter than traditional single faced panels and don’t require any moving parts. Then there’s also the option of mounting panels on stilts, which allows farming machinery to pass underneath. In this design you have to maintain a certain clearance between rows to protect the stilts from the machinery, so there is a modest arable land surface loss, usually 3-10%.

2022-09-14: A similar thought process is to combine solar with dams.

Utilizing even small tracts of water can yield outsized benefits. EDP’s Alqueva array, for instance, takes up just 0.016% of the reservoir total surface area. The relative footprint is even smaller when taking into account the reduced need for transmission infrastructure, as the project can plug into the dam’s pre-existing lines.

Moreover, panels and water can have a symbiotic relationship. Modeling the effects of floating panels on water reservoirs found that floating solar panels could reduce evaporation of the water beneath them by 42%. Conversely, solar panels lose generating capacity as they heat up, and the water helps keep panels cool — and 10% more efficient.

2023-06-26: Luminescent Solar Concentrators strike a good balance of energy / agricultural performance.

The idea of Agri-LSC is to allow visible light that crops use for photosynthesis to pass through the panel, while capturing wavelengths of light that are unusable for plants, like infrared and ultraviolet, and converting them into electricity or even transforming them to aid with crop growth. UbiGro is a transparent film that implements a method of LSCs to increase yield for everything from strawberries to cannabis by 20%. They recently teamed up with the solar module company Heliene to add UbiGro film to solar panels, simultaneously generating electricity from low light while aiming to increase plant yield.

https://www.youtube.com/watch?ww-_U7_oQbY?t=325

Casein Fermentation

Vegan cheese has been quite disgusting to date. But not the mozzarella that I tasted. The missing ingredient has been the casein protein of milk (and until now, it could only be had from milk). Melding innovative microbial fermentation science and traditional cheesemaking, New Culture’s mozzarella is the first animal-free cheese to melt and stretch. When I tasted it, it tasted, smelled, and stretched like milk cheese. The cheese is healthier (cholesterol and lactose-free) and better for the environment: of all food products, cheese requires the most water and is 3rd in greenhouse gas emissions and land use. Producing cheese from casein fermentation rather than animal milk reduces greenhouse gas emissions, and land and water usage by orders of magnitude, making the New Culture approach radically more climate-friendly than animal farming.

2023-03-13: A bit more progress

28 companies have sprouted up to develop milk proteins made by yeasts or fungi. The companies’ products are already on store shelves in the form of yogurt, cheese and ice cream, often labeled “animal-free.” The burgeoning industry, which calls itself “precision fermentation,” has its own trade organization, and big-name food manufacturers such as Nestlé, Starbucks and General Mills have already signed on as customers.
The dairy industry, with its clout and hefty lobbying budget, may not agree there is room for everyone: In 2022, US cow dairy had ceded 16% of all retail milk sales to plant-based milk. Plant-based milk companies also may not welcome the competition, especially if cultivated dairy products are positioned as more sustainable and less resource-intensive. A glass of almond milk takes 90 liters of water to produce.

Haber-Bosch

50% of the nitrogen in our bodies came from the Haber–Bosch process. It’s in every protein and every strand of DNA. Ponder that — “50% of the nitrogen in your blood, your skin and hair, your proteins and DNA, is synthetic.” The Haber-Bosch process catalyzes the production of ammonia (NH3) from N2 and H2 gas. We need “fixed nitrogen”, available to our organic chemistries as atomic nitrogen. It is the limiting factor for the growth of all food. While nitrogen gas is about 80% of our atmosphere, not one atom of it is available for our use when tightly bound by the triple bond of N2 gas, the strongest chemical bond in nature. It is sequestered all around us. In nature, N2 is liberated to atomic nitrogen in small amounts by lightning strikes (it needs 1000°C) and slowly by nitrogen-fixing bacteria in the soil. Hager argues that if we reverted to relying on just those natural sources, 3b people would die of starvation in short order — our soils simply could not produce enough food for the mouths now on Earth. The Haber process consumes 4% of the world’s natural-gas production and 1.5% of the world’s energy supply.

2021-11-30: There’s a potential replacement:

The process is as clean as the electricity used to power it, and produces around 53 nanomoles of ammonia per second, at Faradaic efficiencies around 69%. The highest reported previous efficiencies for ammonia electrolysis sat around 60%, with the exception of 1 other lithium cycling approach that managed 88%, but required high temperatures of 450 °C. The team says it’s massively scalable, capable of operating either at industrial scale, or in extremely small on-site operations. “They can be as small as a thick iPad, and that could make a small amount of ammonia continuously to run a commercial greenhouse or hydroponics setup, for example.” This kind of distributed production model, as we explored looking at FuelPositive’s modular, container-sized ammonia production units, would have additional benefits in that it would eliminate the distribution and transport that contribute significantly to the financial and emissions costs of the current ammonia model.

2022-05-04: What happens when you think you can do without Haber-Bosch.
2022-07-22: The same team was able to improve ammonia electrolysis further, with 3x yield and nearly 100% energy efficiency.

We investigate the role of the electrolyte in this reaction and present a high-efficiency, robust process enabled by compact ionic layering in the electrode-electrolyte interfacial region. The interface is generated by a high-concentration imide-based lithium salt electrolyte, enabling stabilized ammonia yield rates of 150±20 nmol s-1 cm-2 and current-to-ammonia efficiency closely approaching 100%.

Web Photoshop

This has to be some kind of high water mark for web capabilities. Pretty late in the game, unclear that it matters much? For example, will WebAssembly take full advantage of Apple custom silicon?

Over the last 3 years, Chrome has been working to empower web applications that want to push the boundaries of what’s possible in the browser. 1 such web application has been Photoshop. The idea of running software as complex as Photoshop directly in the browser would have been hard to imagine just a few years ago. However, by using various new standardized web technologies, Adobe has now brought a public beta of Photoshop to the web.

Wavelets

Built upon the ubiquitous Fourier transform, the mathematical tools known as wavelets allow unprecedented analysis and understanding of continuous signals.

Fourier transforms have a major limitation: They only supply information about the frequencies present in a signal, saying nothing about their timing or quantity. It’s as if you had a process for determining what kinds of bills are in a pile of cash, but not how many of each there actually were. “Wavelets definitely solved this problem, and this is why they are so interesting” A signal could thus be cut up into smaller areas, each centered around a specific wavelength and analyzed by being paired with the matching wavelet. Now faced with a pile of cash, to return to the earlier example, we’d know how many of each kind of bill it contained. Part of what makes wavelets so useful is their versatility, which allow them to decode almost any kind of data. “There are many kinds of wavelets, and you can squish them, stretch them, you can adapt them to the actual image you are looking at”. The wave patterns in digitized images can differ in many aspects, but wavelets can always be stretched or compressed to match sections of the signal with lower or higher frequencies. The shapes of wave patterns can also change drastically, but mathematicians have developed different types, or “families,” of wavelets with different wavelength scales and shapes to match this variability.

Most important century

The “most important century” series of blog posts argues that the 21st century could be the most important century ever for humanity, via the development of advanced AI systems that could dramatically speed up scientific and technological advancement, getting us more quickly than most people imagine to a deeply unfamiliar future.

The long-run future is radically unfamiliar. Enough advances in technology could lead to a long-lasting, galaxy-wide civilization that could be a radical utopia, dystopia, or anything in between.

The long-run future could come much faster than we think, due to a possible AI-driven productivity explosion.

The relevant kind of AI looks like it will be developed this century – making this century the one that will initiate, and have the opportunity to shape, a future galaxy-wide civilization.

These claims seem too “wild” to take seriously. But there are a lot of reasons to think that we live in a wild time, and should be ready for anything.

We, the people living in this century, have the chance to have a huge impact on huge numbers of people to come – if we can make sense of the situation enough to find helpful actions. But right now we aren’t ready for this.

Radioactivity & deep time

Radium forever transformed attitudes to time and where we may be within history – creating the first efflorescence of truly long-term thinking. Until that point, we knew the Earth was old, but hadn’t fully embraced how many more millions – or even billions – of years could lie ahead for humanity and the planet. In Europe, Christians assumed they were much closer to time’s end than its beginning. Judgement Day was anticipated soon. Then, the 1900s dawned, and radioactivity was discovered. This changed everything. From thinking they lived near history’s end, people now recognized they could be living during its very beginning. Humanity’s universe, no longer decrepit, now seemed positively youthful.

Glasses history

In his book Kitāb al-Manāẓir (Book of Optics), written in 1021, the Arab mathematician Ibn al-Haytham, also known as Alhazen, was the first to recognize and describe the magnifying property of curved glass surfaces and to put it to practical use by making reading globes. Despite the groundbreaking significance of this discovery, it remained unknown in the West for a long time because it was published in a treatise written in Arabic. It was not until the end of the 12th century that Alhazen’s treatise was translated into Latin by Franciscan monks in Italy, revealing to the Western world that an object was magnified when viewed through a transparent spherical element. The translation of the Book of Optics provided not only a physical explanation but a practical insight: convex polished hemispheres made of certain semiprecious stones magnified letters when placed on them. These reading stones were the first vision aids to be used systematically.

Multicellular Emergence

Environments favoring clumpy growth are all that’s needed to quickly transform single-celled yeast into complex multicellular organisms.

During the first 100 days, the clusters in all 15 of the tubes 2x in size. Then they mostly plateaued until the 250th day, when the sizes in 2 of the tubes that didn’t use oxygen started to creep upward again. Around day 350, Bozdağ noticed something in 1 of those tubes. There were clusters he could see with the naked eye. “As an evolutionary biologist … you think it’s a chance event. Somehow they got big, but they are going to lose out against the small ones in the long run — that is my thinking. I didn’t really talk about this with Will at the time.” But then clusters showed up in the 2nd tube. And around day 400, the 3 other tubes of mutants that couldn’t use oxygen kicked into gear, and soon all 5 tubes had massive structures in them, topping out at about 20000X their initial size. “I wasn’t honestly sure if this was a system that would saturate at 1000 cells. We have to continue evolving them and see what they can do. We need to see, if we push these guys as far as we can for decades, for 10000s of generations. If we don’t do that, I will always regret not having taken the opportunity. It’s a once-in-a-lifetime opportunity, to try to push a nascent multicellular critter to become more complex and see how far we can take them.”

2022-11-05: Multicellularity has metabolic benefits

the hollow spheres were Vibrio’s solution to the complicated challenge of eating at sea. An individual bacterium can produce only so much enzyme; breaking down alginate goes much more quickly when Vibrio can cluster together. It’s a winning strategy — up to a point. If there are too many Vibrio, the number of bacteria outstrips the available alginate.

The bacteria resolved the conundrum by developing a more complex life cycle. The bacteria live in 3 distinct phases. At first, an individual cell divides repeatedly and the daughter cells huddle in growing clumps. In the second phase, the clumped cells rearrange themselves into a hollow sphere. The outermost cells glue themselves together, forming something rather like a microscopic snow globe. The cells inside become more mobile, swimming about as they consume the trapped alginate. In the third phase, the brittle outer layer ruptures, releasing the well-fed inner cells to start the cycle anew.
By altering their life cycle to include a multicellular stage, the bacteria can digest the alginate efficiently: Their numbers increase, and the hollow shell helps to concentrate the enzymes. Meanwhile, the structure of the community prevents too many cells from being born. The cells in the shell lose the opportunity to reproduce, but their DNA lives on in the next generation anyway, since all the cells in the orb are clones.