Non-minimum-phase dynamics in an inflammation model

Inflammation is the innate immune system’s response to tissue damage caused by trauma or infection. Thinking about it as the quickly receding rash after an insect bite detracts from the major antagonistic role it plays in medicine. As Baldur Tumi Baldursson of the National University Hospital of Iceland put it, `I tell my students, your work is inflammation. Practically all of internal medicine is just fighting inflammation.’

Inflammation is a complex process involving different cell types, mediator molecules and changes in the permeability of capillaries and affected tissue. This reaction has to be ramped up quickly to defend our body, but it must also be kept under strict control to prevent immune cells causing tissue damage themselves. On occasion, things go wrong and a patient is left with chronic, abnormal inflammation: inflammatory bowel disease, coeliac disease or rheumatoid arthritis are a few debilitating examples.

A mathematical model of inflammation control

These notes extend the findings of three researchers from Britain—Joanne Dunster (Reading), Helen Byrne (Oxford) and John King (Nottingham)—using control theoretical insights, and perhaps contribute a new aspect to our understanding of the problem. Their 2014 paper1 drew attention to a shift from understanding inflammation resolution as a passive process to an active, anti-inflammatory mechanism. Continue reading

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La La Land: a peer review

This weekend I saw the critically acclaimed new Hollywood musical, La La Land. I can warmly recommend it to my generation of nomadic, globetrotting, aspiring, bright-eyed and bushy-tailed academic scientists. It’s touching.

la_la_land

SPOILER ALERT: My clumsy words will completely spoil your enjoyment whether you’re planning to watch it or have already done so. Continue reading

Music cognition: probing the mind with music

What can you learn about a person from what music they like? Can you expect a difference in predisposition between those who prefer upbeat music versus those who like melancholic music? Do people with a taste for complex music have better cognitive skills, or is it a learned taste that results from devoting more time to the subject, or something else? Can a music streaming service make money through targeted advertising based solely on music preferences? Following from that, should we guard our musical taste closely? What might a future adversary infer about ourselves from our taste in music? Is it or will it be possible to scientifically predict which songs will be hits? If yes, can this capability be used during composition already?

I jumped the gun here by starting with the inverse (the inference) problem. The direct question is: do personality traits influence preferences for certain musical styles? This statistical framing assumes that there are hidden variables describing our personality and musical preferences are their functions, which can be observed. We will see that they do correlate.

Why do people differ so much in what music they like? More fundamentally, why do we like music? It seems most everyone likes music. Does this affection give us an evolutionary advantage, or is it just a neutral side effect of something that is advantageous? What percentage of us don’t like music? Are they a small minority, as social convention leads us to believe, or is there actually a silent majority for whom music is a nuisance? If they were a rarity, perhaps they are interesting subjects for psychological studies. How does rhythmic music suck many of us in and make us move with the beat? Shouldn’t we be better at controlling our bodies, at jamming such stimuli? Or is jamming more costly for some minds than moving with the rhythm? Continue reading

The day when the singularity came

A philosophical sci-fi essay about what to do with your life using some new data, with a reading list for rainy Sunday afternoons

It was the 27th January 2016 when the penny finally dropped. It was reported that in October 2015, Google’s artificial intelligence program had beaten the European champion of the board game Go.1 She had a nagging feeling that this was not right. It was only a year and a half ago when she read the expert opinion that for computers Go is so much harder than chess that it would take ten years for a computer to beat a top professional human player. Continue reading

When are kids born? Anyway, when are babies conceived?

My current subject is the seasonality in the number of births. I have looked up the number of live births in several countries over a number of years with monthly resolution. My primary question is whether there are certain months of the year in which more babies are born than could be expected.

There are a few other related, truly intriguing questions, but we will not be able to say much about them based on the available data beyond mere speculation. The most directly accessible one is the seasonality in conception rate: to what extent is it defined by seasons (time spent indoors and the like), and how much influence does culture have on it? What would also be very interesting to find out is the seasonality in the number of sexual intercourses. Well, I can’t say much about the latter one, but I will explain why. Continue reading

The moat approach to scientific authority — Beware of the guru!

Warren Buffett, perhaps the greatest investor of all times, prefers his holdings to have what he calls a `moat’; some form of protection that sets a business apart from the competition, similarly to how a moat protects a castle from intrusion.1 The economic moat should function by making it impossible for rivals and new entrants to outcompete the established one. It can be a cost advantage, a well-known brand, a cemented connection with customers, infrastructure already in place, or special know-how, possibly a patent portfolio.

If you believe in keeping science open, then you should be wary when you sense something similar happening in research. Continue reading

Height matching for a harmonious-looking pair

I’m somewhat obsessed with the heights of people around me. I also have an interest in harmony and aesthetics. So I have been thinking what height proportions make a nice couple. If you are looking for a partner from the opposite sex (whether for a romantic relationship or for dancing), what height would be a good match to yours?

What follows is going to involve data analysis but there will be nothing inherently scientific about it. Continue reading