Why is urine yellow?

I must admit that this is not a question that I had been wondering about, mainly because I assumed that the reasons would have been known some time ago, given our current ability to do microanalysis of pretty much anything.

So I was surprised to learn that researchers have only just found the reason, that it is due to a particular microbial enzyme.

The enzyme is called bilirubin reductase, and it’s a result of the degradation of red blood cells. Once they break down, a bright orange pigment called bilirubin is produced. Typically, bilirubin is secreted into the gut where it has to be discharged. It can also be reabsorbed, which in excess can cause jaundice, which is when a person’s skin and eyes become yellow.

“Gut microbes encode the enzyme bilirubin reductase that converts bilirubin into a colorless byproduct called urobilinogen,” lead author Brantley Hall, an assistant professor in the University of Maryland’s Department of Cell Biology and Molecular Genetics, said in a media statement. “Urobilinogen then spontaneously degrades into a molecule called urobilin, which is responsible for the yellow color we are all familiar with.”

Now at any parties social gatherings, whenever the conversation turns to the topic of urine, you can impress your friends this little factoid.

You can read the paper that was published in Nature Microbiology here.

Recycling wastewater for drinking

The state of California in which I live has had many years of drought leading to water shortages. While conserving water is one way of addressing the problem, another is to increase the supply. One option is to use desalination plants but those are expensive to build and operate. Another is to reclaim wastewater for use in things like irrigation. But recently the state has gone one step further and approved reclaiming wastewater for human consumption.

When a toilet is flushed in California, the water can end up in a lot of places: an ice-skating rink in Ontario, ski slopes around Lake Tahoe, farmland in the central valley.

And – coming soon – kitchen faucets.

California regulators on Tuesday approved rules to let water agencies recycle wastewater and put it into the pipes that carry drinking water to homes, schools and businesses.
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AI and the vagaries of language

A recent article took a detailed looked into the dramatic and rapid sequence of events involving the firing of Sam Altman as the head of OpenAI by its board of directors, the subsequent resignations of much of the top talent, the immediate hiring of them by Microsoft (which was an investor in OpenAI), and the resignation of the Open AI board and the return of Altman and others to the company, all within the space of less that a week.

It is not the corporate maneuvering that I want to write about but the potential and dangers of AI. There has been a great deal written about the new generation of AI software and whether it stays at the level of being large language models that seem to mimic intelligence but still require constant interaction, direction, and supervision by humans or whether they achieve the more advanced level of artificial general intelligence (AGI), that is close to human intelligence and can function much more autonomously, and where that could lead.

Some employees at OpenAI and Microsoft, and elsewhere in the tech world, had expressed worries about A.I. companies moving forward recklessly. Even Ilya Sutskever, OpenAI’s chief scientist and a board member, had spoken publicly about the dangers of an unconstrained A.I. “superintelligence.”

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Why do we still have smoking in films?

There is a lot of smoking in films that are set back in the days before smoking became well known as a serious health hazard. For example, in the film Maestro that I reviewed a few days ago, Bradly Cooper who plays Leonard Bernstein has a cigarette in his mouth pretty much all the time. This caused me to wonder if those were real cigarettes, because it did not seem right to have actors risk their lives with cigarette smoke just to play a role. Films now routinely carry a disclaimer that no animals were harmed in the making of the film, which is a welcome development, but why do we not carry that over to the actors?

This article explains that film makers often use prop cigarettes instead of tobacco-based ones.
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Using OLC coordinates as addresses

Carmel-by-the-Sea (usually just called Carmel) is a small, upscale, touristy town of boutique shops and restaurants that is adjacent to Monterey where I live. It received a lot of publicity for a short time when Clint Eastwood, one of its residents, was elected mayor from 1986 to 1988. I do not know if his campaign slogan was “Do you feel lucky, punk? Well, do you?”

It is a town that eschews the usual system of identifying houses, since none of the houses have a street number. This causes all manner of problems (not the least being the inability of emergency vehicles to find their destinations in a hurry) as I discussed in a post last year. But efforts to bring the town in line with the standard system arouses fierce opposition from some residents. “In 1953, the city even threatened to secede from California when the state considered making it mandatory to have house numbers.” This was of course a ridiculous threat since there is no way that a tiny town could practically function on its own, even if it was allowed to secede. But threats to secede are often brought up in the US by those who feel aggrieved for one reason or another, even over absurdly trivial issues like this.
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Was Y2K an overhyped threat?

Remember the Y2K panic? There were fears that computers that came into widespread use in the mid-twentieth century, when the year 2000 seemed very far away, had been programmed with internal clocks that assumed that the first two digits of the year was 19. There was concern that when the year 2000 rolled around, many systems would crash because the computers might think the year had suddenly reverted to 1900 and thereby go awry. There were fears of planes crashing, power systems going down, the banking and financial sectors going haywire, and so on.

There was a lot of activity among computer professionals to take steps to solve the problem before the end of 1999. I personally did not do anything since I am not a computer professional. I also tend not to wait up on December 31 until the New Year rolls around but on that day I did decide to stay up until midnight to see what might happen. And there was … nothing. Everything was just as before.
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What would a criminal justice system in the absence of free will look like?

I read the new book Determined: A Science of Life Without Free Will by neurobiologist Robert M. Sapolsky where he outlines the biological basis for why we have no free will. I will discuss the main arguments of the book in a later post but here I want to outline what he says about an objection that believers in free will often raise, and that is that if we say that all our actions are determined by our genes, history, environment, and random factors, and that we did not freely choose to do them, then people who commit crimes should not be blamed and punished. He agrees that such people should not be blamed for what is after all outside their control and that retributive and punitive punishments, that form such a large part of our criminal justice system, have no place. But that does not mean that we simply do nothing.

He sets up his argument by recalling how things have changed so dramatically over time in the way that we respond to people with illnesses like epilepsy or schizophrenia that cause them to act in ways that are dangerous to themselves and to others. (Chapter 13, pages 300-340) In the past, it used to be thought that their actions were freely chosen ones and they were punished accordingly, often in horrendous ways. Not anymore. Now we realize that they are victims of illnesses that cause them to behave in those ways, and we have changed our response accordingly. As he says: “Once, having a seizure was steeped in the perceptions of agency, autonomy, and freely choosing to join Satan’s army. Now we effortlessly accept that none of those terms make sense. And the sky hasn’t fallen. I believe that most of us would agree that the world is a better place because sufferers of this disease are not burned at the stake.” (p. 316)
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What AI systems know about me

I saw a couple of recent posts by people who had asked AI systems for information about themselves. Asking these system to tell you information about yourself is a good way to see if they are making up stuff because presumably you know your own life better than anyone or anything else. They reported that after giving out information that was correct, it suddenly seemed to veer off and simply make up stuff about them.

Curious, I decided to try this for myself. I asked ChatGPT “What can you tell me about Mano Singham?” and got back this response.

Mano Singham is a theoretical physicist, author, and retired professor. As of my last knowledge update in January 2022, he is known for his contributions to the field of physics and for his writings on science, education, and atheism. Mano Singham has held the position of Director of the University Center for Innovation in Teaching and Education (UCITE) at Case Western Reserve University.

In addition to his academic work, Singham has been an active writer and blogger. He has written extensively on topics related to science, secularism, and rational thinking. One of his notable works is the book “The Simpsons and Their Mathematical Secrets,” where he explores the mathematical references and jokes hidden in the popular animated TV show “The Simpsons.”

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How safe are self-driving cars?

I for one would really like to see self-driving cars become an everyday reality, as common as cars are now. It may surprise people that many such cars are already widely used in several cities as taxis. But there are key questions concerning safety and one would hope that the companies marketing these cars would be transparent about the ability of their cars to detect pedestrians and obstacles. But Sam Biddle writes that one major company is putting its cars out on the streets even though it seems to have two key vulnerabilities: an inability to see small children and large holes in the ground.
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