Sunday, 26 November 2017

Talk : "Who's Eating Who? Hominins and Carnivores in Human Evolution"

We have not always been the alpha predator on this planet - Dr Hannah O'Regan give this month's public lecture on "Who's Eating Who? Hominins and Carnivores in Human Evolution"

@Gav Squires was there and has kindly written this guest post summarising the event, with some linkage added by NSB.

Hannah O'Regan

To begin with, why carnivores?
Social carnivores could be a good proxy for hominins and their development. They have been in competition with hominins for resources such as food, water and shelter. They are primate predators.

7 million years ago, the first hominin, Sahelanthropus, evolved. 3.9million years ago, we had Australopithecus, the best known example of which is Lucy and 3.3million years ago, we have the earliest archaeology with evidence at the Lomekwian site of the use of stones. Evidence has been discovered from 3.4million years ago of marks on bones, implying that humans had used tools to remove flesh, which they then presumably would have eaten. 2.8million years ago the genus homo made their first appearance and 2.6million years ago was the first use of stone tools. 1.5million years ago, we have Acheulan tools, hand axes and we have bipedal hominins wandering the landscape with tools.

Artistic interpretation of Sahelanthropus tchadensis
by sculptor Élisabeth Daynès

Acheulan tools

Between 1 and 2million years ago there were a range of large carnivores in Africa including 6 types of hyena, canids including those the size of wolves and African dogs. There were also a number of felids that could take down a hominin including lions, cheetahs, leopards and sabre-tooth cats. Sabre-tooth cats were ambush predators with very powerful front-legs that they would use to wrestle prey into position so that it could use its teeth. The teeth were longer than they were wide, which made them susceptible to breaking. However, if they did break it would mean that the animal would be forced to scavenge and would not have lived for much longer afterwards. In Swartkrans in modern-day South Africa, evidence has even been found of human remains that have been predated by leopard.

As well as large carnivores, there is also predation by birds and things such as eagles will hunt primates - there is plenty of evidence in the form of primate bones beneath the nests of Crowned Eagles. The Taung child, the first ever fossil published of a hominin from Africa was discovered in 1924, was 3-4 years old when it died and the only hominin fossil ever found in Taung in South Africa. It has similar orbital damage to primates eaten by eagles and it appears that there was no population at Taung and the child was carried there by an eagle.

Evidence has also been found of crocodiles predating hominins from 1.8million years ago. Another example from down the same river has crocodile teeth marks on its foot and has also had its leg bitten off by a leopard - not a great day!

The Homotherium was one of the sabre-toothed cats that lived in Africa and Europe that seem to have died out in Europe around 28,000 years ago. In Schöningen in Germany, evidence of humans using spears 300,000 years ago has been found - the humans were mainly preying on horses at the time. There is also evidence that these humans were using the bones of Homotherium as hammers in order to make stone tools.

Artists impression of Homotherum

How can we tell the difference between predation and scavenging? It's actually very difficult as teeth will make the same marks in both cases. Looking at some Neanderthal bones, there are some fox bite marks on the hands that are clearly scavenging but there are also bite marks on the skull from a larger animal, which could be either.

While it is extinct in the UK these days, the brown bear in Europe's largest carnivore. In Ireland, a bear patella has been found showing evidence of marks from stone tools where the patella tendon has been cut. This is the first evidence of humans living in Ireland but we still don't know what they would have been using the patella for once it was removed. More recently the Romans brought bears to the country and in the 16th century there were a number of bear baiting arenas in London. By the 18th century bear shaped ceramic were being made in Nottingham, depicting bears holding dogs and even in the early 20th century, Italians were bringing over dancing bear cubs for the summer season.

 
European Brown Bear

These days we are the apex predator and this isn't necessarily a good thing for the other carnivores, for example the African lion population has dropped by 42% in the last two years. Recently a lynx that had escaped from a zoo was shot in Wales, despite the fact that there have never been any recorded attacks on humans by lynxes. There have been talks over the last few years about the possibility of rewilding species such lynx into the UK, could that still be an option?

We have interacted with and evolved alongside carnivores for millions of years and even now, without adaptations such as fire, weapons and defensive protection, we are vulnerable to predators. However, overall, carnivores are on the back foot against the spread of homo sapiens.

The Public Lecture Series returns on the 7th of December at the University of Nottingham at 6:00pm where Dr Craig Sturrock will talk on 3D X-Ray Vision: Measuring the Hidden Structure of Biomaterials Using X-Ray Computed Technology. For more information, check out the PLS website: https://www.nottingham.ac.uk/physics/outreach/science-public-lectures.aspx

Image Sources
Sahelanthropus, Cordiforme, Homotherium, Bear

Saturday, 25 November 2017

Talk - The Skyscraper - From mid-20th Century to 2030

For November's Café Sci, David Nicholson-Cole from the University of Nottingham comes to talk on "The Skyscraper - From mid-20th Century to 2030".

@Gav Squires was there and has kindly written this guest post summarising the event, with some linkage added by NSB.

David Nicholson-Cole

There were 4,500 years between the building of the pyramids in Egypt and Lincoln Cathedral, which was then the tallest building the world for 238 years[1311–1549, when the large central spire collapsed]. Now, the gap between the record being broken is coming down all the time and a new world's tallest building is crowned around every five years. Originally tall buildings were built to display the concepts of eternity, wealth and destiny and very little has changed.

Model of Lincoln Cathedral (the large central spire collapsed in 1549)

But what is a tall building? These days, it needs to be over 100 metres tall and must be occupied. So, the Eiffel Tower doesn't count. Usually, wide buildings aren't considered to be tall even if they are actually pretty tall, for example Queen's Medical Centre doesn't feel like a tall building but it's 10 storeys high. There really should only be one iconic tall building per city. While tall buildings should have utility, the top 300 metres of the Burj Khalifa, the tallest building in the world today, aren't used - they are just there for the look.

Burj Khalifa, 2010

In 2010, half of the world's population were living in cities and urbanisation is increasing at the rate of 200,000 people per day - a city the size of Manchester has to be built every week just to keep up. By 2030, it will be 60 of the world's population and by 2050, a massive 70% of people will live in cities. Will we keep up? If we do, it will probably be due to more tall buildings.

Skyscrapers originally started in America and apart from the occasional iconic one here and there, they never really caught on in Europe. Now, most expansion is happening in East Asia and 10 out of the 14 cities with the most tall buildings can be found in East Asia - Hong Kong alone has 2,354 buildings over 100 metres tall. Now, the average height for a super-tall building is 350 metres. Originally, tall buildings would all be used for office space as only offices could afford to build tall. They have since had to evolve into multi-use buildings as that is the only thing that makes economic sense. In the Middle East and China, they prefer building with stone rather than steel but here in the UK, steel is used for tall buildings. Cities with tall buildings and good transport links are the most energy efficient.

Tall buildings in Hong Kong

A proposal for building on the banks of the river Hudson in New York saw the land valued at $110,000 per square metre. This is why going tall becomes so popular - to make it pay you have to go tall and have to go mixed-use. The site in New York was 1,000 square metres in size so it would have cost $110,000,000 just for the land. The reason that the land is so expensive is that places like New York and London have such massive demand for housing that it pushes the prices up and means that you have to build tall.

  The two key inventions that enabled tall buildings to be constructed were the elevator (the first safety elevator was built in 1852) and the steel frame (introduced in the mid-19th century). There were other inventions during the so-called "gilded age" of America between 1869 and 1901 that were crucial to the development of tall buildings:

AC electricity
Telephone
Typewriter
Electric light
Discovery of mineral oil
Railway
Universal post
Electric tram
Elevated railway
Sprinklers

Sprinklers especially were important as before them, buildings could not be made taller than 75 feet high following the great fire of Chicago, which was actually bigger than the fire of London.

Aftermath of the Great Fire of Chicago, 1871

In 1884, the first high-rise residential building was constructed - the Dakota building in New York (the building that John Lennon was shot and killed outside) and in 1885 the 10-storey Home Insurance building opened in Chicago. These first generation tall buildings were built using steel - the Monadnock building, also in Chicago, was originally built using brick but was too heavy and started to sink into the Chicago mud. In the 1920s, the second generation of tall buildings saw form follow finance.

The Dakota Building, c.1890 - at the time,
this area of Manhattan was sparsely developed, and remote
from the core of the city's population

Home insurance Building

The Monadock Building

Between the 1950s and the 1980s, the third generation [also known as the "International Style"] saw dark glass boxes becoming popular. Post the 1970s energy crisis, generation four was still largely glass boxes but they were becoming more efficient. We are now firmly in the 5th generation where energy efficiency and sustainability are the keys to design. The Bosco Verticale, in Milan, is a green building, with facades that contain living plants and hints the way towards the next generation of tall buildings.

The Seagram Building

The Boscoe Building

In terms of maximum height, the only limiting factor is really the number of lifts - the higher that you go, the more people will be using the building and so the more lifts you need. Right now, a 1 kilometre tall building is being constructed in Jeddah in Saudi Arabia. While the future will bring new tall buildings, what will happen to the old ones as they become obsolete, which generally happens between 30 and 40 years after they are built. Only three buildings taller than 160 metres have ever been demolished, they have mainly been refurbished.

Jeddah Tower (under construction as of 2017)

Café Sci returns to the Vat & Fiddle on the 11th of December at 8:00pm where Lucy Donaldson will talk about "Bitter Now But Better Later?" For more information, visit the Café Sci MeetUp page https://www.meetup.com/nottingham-culture-cafe-sci/

Image Sources
Lincoln Cathedral, Burj Al Khalifa, Hong Kong, Chicago Fire, Dakota Bldg, Home Insurance Bldg, Monadock Bldg, Seagram Bldg, Bosco Verticale, Jeddah Tower

Related Links
Article by David Nicholson-Cole

Saturday, 11 November 2017

Slinky Science 'Speriment


BFTF is a big fan of science. All the wonders of the modern age, all out comforts, our medicines, our transportation, our communications. . . are built on the scientific endeavours of the last few hundred years.

Maybe it's just me, but whenever I use the word "scientific" I feel a little like Yul Brenner in "The King and I" - not in a good way!

Unfortunately, it can be hard to easily demonstrate the key elements of scientific enquiry in a domestic setting - or so BFTF thought until it found itself helping a pint sized relation with a small science project on springs.

We taped up the top half of a slinky spring, and taped some paper over the bottom of the slinky to act as a base where we could add weights.





We then measured the length of the slinky (measuring from the bottom of the taped section to the paper base) which was 14cm.

Next, we progressively added pound coins to the paper base, measuring the length of the spring each time (24, 34, 44cm with 1,2,3 coins respectively)

Once we got to three coins we plotted the data on a graph and drew a "best fit" line thought the points.




We then - get this - predicted what the extension would be for 4 coins and for 5 coins and checked to see what actually happened.

Well, my gob was truly smacked when it turned out that our prediction for the length of the slinky with 4 pound coins was absolutely spot on and the prediction for the length with 5 pound coins was accurate to within 1cm !!!.

We had performed an experiment, plotted the data, made a prediction for what would happen next, tested our prediction and found that it was quite accurate. It doesn't get any better than this!

So, gentle reader, there you go. A science experiment that ticks all the boxes and can easily be performed at home (no bunsun burner required!).

If you know of any easy science experiments, particularly any that allow you to make predictions about future behaviour, why not describe them in the comments section below.

The (counter-intuitive) Monty Hall Problem

There are some things in life that are really counter-intuitive.

We accept many of these because the evidence is right there before our eyes and we are used to them (e.g. a box in my front room that displays a moving image received through thin air? You gotta be kidding me right?)

But some, less common, phenomena still have the capability to confuse us. A good example of this is the "Monty Hall Problem", which is often stated as :


Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1 [but the door is not opened], and the host, who knows what's behind the doors, opens another door [that does not have the car behind it], say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice?


Intuitively, one feels that switching door should not make any difference - you have a 50:50 change either way.

But, weirdly, this is not the case - in reality, you have a much higher chance of getting the car if you change doors.

I know, I know, it seems to go against common sense, and indeed when this conundrum was published in Parade magazine, some 10,000 readers, including almost 1,000 with PhD's wrote in to complain that the article was wrong and that changing doors did not make any difference.

With the problem being so simple, NSB decided to simply knock up an excel spreadsheet and see what happens. The geeky stuff is at the bottom of the post, but the take-home-message is that running the problem 100 times gives the following results :

Never switch door : Win 35% of the games
Always Switch door : Win 65% of the games
Toss a coin as to whether to switch or not : Win 55% of the games



Crikey, switching really does improve your chances of winning! How spooky!

Just goes to show how the human mind can be tricked. The Wikipedia article on the Monty Hall Problem is surprisingly long and discusses many of the psychological issues related to how people perceive the problem.

Here comes the Geek bit (from a random line of the spreadsheet, line 3 in this case) :

Column B : Randomly choose which door the prize is behind
Excel Formula: =RANDBETWEEN(1,3)

Column C : Contestant randomly pick a door
Excel Formula: =RANDBETWEEN(1,3)

Column D : Outcome if contestant sticks (win=1)
Excel Formula: =IF(C3=B3,1,0)

Column E : Outcome if contestant switches sticks (win=1)
Excel Formula: =IF(D3=1,0,1)

Column F : Toss to switch (stay=1)
Excel Formula: =RANDBETWEEN(1,2)

Column G : Outcome based on Toss in Column F (win=1)
Excel Formula: =IF(F3=1,E3,D3)

Copy the above onto as many lines as you want and then total up the wins from the different strategies.

Taxonomy, Type Specimens and Art

This article first written in 2012, but as relevant today as it was then....
A fascinating article in the UoN "Making Science Public" blog discusses the role of samples in botany. Written by Maura C. Flannery, Professor of Biology at St. John’s University, NY, the article was a genuine revelation for a non-specialist like NSB.

Durian (Durio zibethinus), Anonymous Chinese artist, ~1820.


Accessing botanical samples
Apparently, for each species of plant that has ever been identified, there is a "type" example that is the definitive example of that species, often collected by the scientist who first catalogued the plant. These "type" examples are kept as pressed specimens attached to paper and stored in "herbaria".

Botanists who are researching the taxonomy (classification) of plants often need to access these type specimens in order to check or examine some point of their structure.

And, for researchers in the developing world, this is where the problems start . . .

... because as a linked article explains, for the Rubiaceae (coffee plant) family, some 430 type specimens (over 95%) of catalogued species are stored in European herbaria (312 in the UK, 127 in Portugal, 99 in Franceand 70 in Belgium). There are only 50 type specimens in African herbaria, all duplicates of "definitive" type sample stored in Europe.

This relative lack of specimens in Africa means that researchers have to travel to Europe just to study speciments - which represents a significant economic burden on botancial departments that are already economically disadvantaged.

Grape Variety (Muscat Hamburgh) Goethe and Lauche, 1895


There are projects (such as the African Plants Initiative) underway to digitally photograph these European herbaria, but the paper suggests that photographs cannot replace phyical examination of actual specimens and points out that if they could then perhaps the photograhps could stay in Europe and the actual speciments returned to Africa.

But returning speciments to Africa has its own issues as they would need to be suitably housed, curated and maintained - again a costly excercise for developing African countries.

Photos versus pictures Another topic covered in the UoN article is that of the role of drawings to supplement the type samples and how drawings can be more useful because the artist is able to filter out some of the extraneous or irrelevant detail to focus on the the important structures of the plant. Indeed, for flora such as fungi, which cannot be dried without drastically changing their appearance, drawings are the key identifying tool.

Arabic translation of Dioscorides "De Materia Medica" c.1200


Other Comments
Whilst digging around on the Interweb to prepare this post, NSB stumbled upon some other interesting related resources.

One is the The Glass Flowers Collection Harvard University which contains over 3000 painstakingly made glass models of various plants. They really are an incredible example of craftsmanship.

Wikipedia has an awesome, gorgeously illustrated, list of Botanical Codices (NSB notes that it much much easier to look at and browse some of these illustrations at Wikipedia than at any of the Universities that are so lavishly funded with taxpayers money.)

Image Sources
Durian, Grapes, Arabic Translation

Wednesday, 1 November 2017

The difference between NUMBERS and RATES

Was talking to No3 Son recently about a piece of science homework in which he had to chart and comment on 2012-2014 cancer statistics. The data was a great example of how the NUMBER of cases can give a very different picture to the RATE of cases. Looking at the NUMBERS chart (red) one might think that 70-79 is where the biggest danger lies. This may be misleading as the graph shows the number of cases not the rate (e.g. per 100,000 people).

Using 2011 census data from Wikipedia, one can work out the number of cases per 100,000 people (blue chart). It is clearly different and now you can see that the older you are the more chance you have of getting cancer.

2012-2014 Cancer Data

Cancer NUMBERS

Cancer RATES

Saturday, 28 October 2017

Dinosaur of China Exhibition

This summer long exhibition at Wollaton Hall showcases some of the incredible dinosaur fossils that have been found in China in recent decades. Many Chinese rocks are unusual in that they are composed on fine sediments which buried and preserved dinosaurs quickly - and preserved their structures in incredible detail.

Feathered dinosaurs formed a large part of the exhibition, but there were many other types of dinosaur on show as well. A few of the exhibits that particularly caught NSB's attention are shown below.

Microraptor
Early Cretaceous, ~120million years ago
This is the first fossil of this type that was found, back in 2003. Microraptor has claws on its hands and feet, FOUR wings and was capable of flight.

Artist impression of Microraptor

Microraptor fossil - you can see the feathers

Sinornithosaurus
Early Cretaceous, ~125million years ago
Fossils of Sinornithodaurus show that the body of this creature was covered in a short fuzz of simple, soft, feathers - giving clues to the steps in feather evolution. It is likely that Velociraptor, a close relative of Sinornithodaurus was also similarly fuzzy.

Artist impression of Sinornithosaurus

Fossil of Sinornithosaurus

Yi Qi
Middle/Upper Jurassic, 160million years ago
A dinosaur with unique wings that were formed from webs of skin, rather than feathers, although it was covered in an insulating fuzz.

Artist impression of Yi Qi



Gigantoraptor
Late Cretaceous, ~80million years ago
The largest known bird-like dinosaur! Clearly too heavy to fly, its feathers may have been used in courtship displays. No-one knows what this large beaked dinosaur ate!

Artist impression of Gigantoraptor
Gigantorapor
Mamenchisaurus
Late Jurassic, 160million years ago
This sauropod is 23m long from head to tail and, in the rearing posture shown in the exhibition, is over 13m tall - higher than three double decker buses! The bones in its neck overlap with each other, which gave support but also resulted in the neck being rigid.


Mamenchisaurus

The exhibition also provided information on some of the key Chinese figures in palaeontology:
Dr Chung Chien Young
Dong Zhiming
Prof Tan Lin who gave a talk on "Ground Shakers and Feathered Flyers" in Nottingham a while back.
Dr Xu Xing


Image Sources
All fossil photos by NSB
All artists impression are photos of exhibition artwork by PNSO

Related Content
Doggerland - Europe's lost continent
The world in 10 Fossils
Susannah Lydons article on the exhibition in the Guardian.

Gabions (rocks in wire cages)

Over the last few years, NSB has noticed the appearance of wire cages filled with rocks (known as "gabions") as a construction material for buildings and in civil engineering - and has been wondering what they are and why they have suddenly started appearing.

Gabion Wall at Nottingham 1

Example of a Gabion abutment
Initially, NSB thought that they were being used for environmental reasons, to allow wildlife to grow and live in all the nooks and crannies between the rocks.

Then NSB thought that they were being used as an anti-grafiiti measure, as it is hard to make a recognisable image when the surface is so irregular.

Turns out that gabions have been used for a long time to stabilize shorelines, stream banks or slopes against erosion. They are also increasingly being used in architectural applications for their "natural" look. Maccaferri, a world leader in the technology comment that :
"The Gabion is, in fact, a peculiar tool. It does not impose itself on the surrounding environment: it perfectly blends into it. A Gabion is almost always filled with natural materials: stones/rocks and, where possible, locally available materials can be used to fill the structure, thereby ensuring that very little is added (and removed) to the surrounding nature....The Gabion, furthermore, “joins” the nature that hosts it: plants and trees can “sink” their roots in the interstices left free by the rock fill, helping to strengthen the overall system. Nature is no longer a passive actor: it is indeed called to “work” in synergy with man-made structures. This is the environmental engineering of the future."

Gabion wall at Nottingham 1

Worth noting that, in the urban environment, its a good idea to ensure that "youths" can't get the stones out through the mesh, as this cautionary tale from Sneinton, Nottingham illustrates.

Update Oct 2017
Saw this rather decorative gabion in Germany recently

Image Sources
Abutment

Sunday, 22 October 2017

Talk : Exoplanets

Café Sci returns after its summer hiatus with Michael Merrifield talking all about exoplanets.

@Gav Squires was there and has kindly written this guest post summarising the event, with some linkage added by NSB.

Exoplanets are defined as those planets that are outside our solar system and we now know of around 3,500 of them that are orbiting various stars.

In the middle of the 18th century, Immanuel Kant gave us the modern view of how the galaxy works based on observations of the solar system. We'd extrapolated our understanding out and applied it to the whole universe and we thought that we knew how everything worked. For example, in the solar system, all of the big planets are outside the ice line whereas those planets inside are smaller. Using ice is one of the easiest ways to make things stick together and we assumed that we would see the same big/small planet split in other star systems.

Prof Merrifield, via Gav Squires

The first exoplanet, the catchily titled HD114762b, was discovered in 1989 by David Latham. It was detected by measuring the Doppler shift as the star was effected by the gravity of the planet. Since it was thought that large planets (HD114762b is about 5-10 times the size of Jupiter) wouldn't be that close to a star and so it was originally misidentified as a brown dwarf star. A pulsar is the end state of a star - as they spin around, they can be used like a clock and are actually more accurate than atomic clocks here on Earth. In 1992, three planets were discovered orbiting a pulsar.

A quarter of the exoplanets that have been discovered have been found using this Doppler shift method, looking for the effect of the planet's gravity on the star that it orbits. Most exoplanets are discovered using the occultation method though. As a planet passes between us and its star it blocks out light from the star. We need a fair bit of luck for this method to work though as the orbit needs to be edge on for us to notice the planet's transit. This technique will give the radius of the planet and the radial velocity will give the mass and so we can calculate the density (as an side, Saturn is less dense than water). It is also possible to tell about the atmosphere of exoplanets and how much light is reflected from their surface.

Kepler6B photometry - showing light from star being blocked as planet passes in front

Occultation can even help to discover moons around exoplanets. In the summer, Kepler-1625b1 was tentatively announced as the first ever exomoon - it seems to be a Neptune-sized moon orbiting a Jupiter-sized planet. Another technique for discovering exoplanets is micro lensing - a star with a planet produces a different effect compared to a star without one. This is better at detecting planets that are further away from the star but it is a one-shot deal as it won’t line-up again.[a list of exoplanet detection methods can be found here]

Exoplanet systems are incredibly common, even our nearest star, Proxima Centauri, which is 4 light years away, has an Earth-sized planet orbiting it. The planet is at 0.05AU from Proxima Centauri and orbits once every 11 days and it could be tidally locked - the same side faces the star in the same way that one side of the moon always faces Earth. Proxima Centauri is a weak star but the planet still gets around 70% of the sunlight that Earth gets. This means that it is around -39oC but there could still be liquid water there if there is a greenhouse effect. However, there is unlikely to be any life as Proxima Centauri is a flare star - it regularly emits massive x-ray stellar flares, irradiating the planet.

Professor Stephen Hawking is involved with a project called Star Shot that would like to send a satellite to visit the planet around Proxima Centauri. By firing a powerful laser at a spacecraft, the size of a postage stamp it would be possible to speed it up to 20% the speed of light so it would arrive in just 20 years. Of course, there is still the issue of creating a satellite that small and many such satellites would need to be sent to cover the possibility that they could crash or fail. Once fired off, it wouldn't be possible to slow them down either so each satellite would only be able to make one fly past of the planet.

Based on existing technology, a more realistic idea may be using a solar sail - a satellite the size of a bar of soap would require a sail the size of 10 football fields. Light from the sun would speed it up, although it would take 80 years to get there. We are already able to make a satellite around that size and we would be able to use Alpha Centauri to slow it down in order to actually take some photographs.

NASA illustration of the unlit side of a half-kilometre solar sail
TRAPPIST is the really contrived acronym for a pair of Belgian telescopes that discovered the TRAPPIST-1 system, which features 7 exoplanets. The star is the size of Jupiter and the planets are orbiting at the same distance as the moons of Jupiter. 3 of the planets are in the so-called habitable zone and all 7 of them are in resonance with each other, which is what has actually led to the stability of the system. The SETI people have been focussing on this system but haven't heard anything yet.

Artist Impression of TRAPPIST -1 System

The term "Hot Jupiter" was coined to describe these massive planets that are close to their stars and their discovery has meant that we have had to rethink what we know about the creation of stellar systems. We are now starting to see the discs around stars - planets from in the gaps in these discs so if we can see these gaps, it implies that planets are starting to form and we can hopefully start to learn more about how planetary systems form.

The European Extremely Large Telescope is currently being built in Chile and is set to be completed in 2025. Its main mirror is 39 metres in diameter and it is proof that we can now do things on the ground that we couldn't even conceive of 10-15 years ago - not all telescopes need to be in space. The EELT will have such sharp images that we'll actually be able to see the planets themselves. We will even be able to tell which wavelengths are absorbed by their atmospheres - if we detect ozone, it would be proof that there is life on a planet.

There is a huge bias in the planets that we have been detecting since it is easier to find big planets - we've just been discovering the easy ones. We are starting to discover some oddities though - it seemed like one start, Tabby's Star, might even have a Dyson Sphere around it. While the changes in brightness emanating from it were relatively consistent with what was expected from a Dyson Sphere but the latest results show that UV & IR absorptions are different, meaning that it looks like it’s just naturally occurring dust.

Café Sci will return to The Vat & Fiddle on the 13th of November at 20:00 where David Nicholson-Cole from the University of Nottingham will talk on The Skyscraper - From mid-20th century to 2030. For more information check out the Café Sci MeetUp page: https://www.meetup.com/nottingham-culture-cafe-sci/

Related Content:
Fee- An Autobiography
Curiosity, Twitter and the British Connection
Interview with Prof Aragon-Salamanca
Interview with Prof Chris Lintott
Some background to the Space Shuttle
Lecture by Chris Lintott on 2011 Astronomy highlights

Image Sources:
Kepler6b Transiting light level, TRAPPIST-1 system Solar Sail

Sunday, 17 September 2017

Pseudoscience on Social Media

Some examples of Pseudoscience on Social Media.

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An article by Robert Walker on "Science 2.0" describes the fear that fake doomesday stories on Google News (and other sites) are causing to children and your adults :

"This is a serious problem. It's not just the misinformation and people growing up with this totally fake astronomy education. These stories are also scary, especially for young children, or young parents with babies, because they usually also tell them that the world is about to end in the next week or month or some other short timescale."

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Via Twitter

US Senator Jim Inhofe sets what may be the gold standard for denialism, back in Feb 2015.

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Via Twitter

The above was Tweeted by East Mids UKIP MEP @RogerHelmer.

Snopes has looked into this article, which originated on Breitbart News, and comments that :

"We reached out to many of the authors of the studies included on this list via email to see if they agreed with Breitbart and No Tricks Zone’s analysis. While not everyone we reached out to responded, not a single researcher that we spoke to agreed with Breitbart’s assessment, and most were shocked when we told them that their work was presented as evidence for that claim."

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Via Facebook

(Post first seen by NSB in 2017).A Facebook post poking fun at pseudoscience conspiracy theories.

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(Post first seen by NSB in 2017.). Does Fluoridation cause cancer? Answer is that there are so few of the most likely cancers (even before fluoridation) that it is difficult to tell. More information in this article by the American Cancer Society.

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Cannabis does not cure cancers
"Dangerous pseudo-science that could get people killed if they use cannabis oil instead of medical advice. In contrast to the claims in the article, there are MANY studies on the effects of cannabisits effects - for example at CancerResearchUK page".

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Anti-Vaccine attitudes get children killed.

This post actively causes harm by discouraging people from getting their children vaccinated. If you want to see what DOCTORS say about flu vaccine, visit this CDC page.

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CERN is not making an anti-matter bomb

Very sensible video until about 6mins in then it starts to fixate on anti-matter, repeatedly saying (accurately) that 1g of antimatter has the energy potential of a nuclear weapon and (also accurately) that CERN has been trying to contain antimatter.

But what is not mentioned (although NSB did not listed to the entire audio) is that the current state of the art is only able to hold about 40 anti-protons, which is 0.000 000 000 000 000 000 000 000 1 g and according to the IOP it would take around 100 billion years to produce 1 gram of antimatter. ********************************

Microwaves are not particles

Lots of errors and misinformation here. To take one example,the article says "They use electrically generated electromagnetic energy to make super-fast particles". But microwaves aren't particles. The clue is in the name. Here is a paper that talks quite comprehensively about microwave oven leakage and safety

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Jun 2013
NSB recently read an article in MailOnine by TV motoring correspondent Emma Parker Bowles on her experience using a leeches to cure migraines.

The article (entitled "Gruesome, medieval and utterly bizarre... but leeches freed me from awful migraines") had a number of characteristics consistent with being "psuedoscience". In particular, the following points caught NSB's attention:

a) Evidence presented does not relate to the condition at hand (migraines)
"In the 1980s, leeches began to be used by reconstructive plastic surgeons needing to remove stagnant blood from reattached limbs, to stave off gangrene. But now there are numerous studies into medical uses for leeches. One found that a single session of leeching – the medical application of bloodsucking leeches – can significantly reduce knee pain caused by arthritis for at least two months. Researchers from the University of Duisburg-Essen in Germany claimed improvement levels were comparable to those achieved with daily moderate doses of painkillers such as ibuprofen... The secret is in the leeches’ saliva: it apparently contains a large number of analgesic, anaesthetic, and blood-thinning compounds that tackle pain and inflammation, say the researchers."
But these are differnet applications to those that Bowles was using the leeches for (i.e. to stop migraines). Whereas the clinical uses mentioned relate to the use of leeches directly on the area affected, the procedure Bowles was undertaking involved the placement of leeches on the side of the head where they were separated from the brain by the skull. And, in any case, it is unlikely that Bowles was experiencing a migraine at the time the leeches were applied, so it seems unclear to BFTF exatly what the "analgesic, anaesthetic, and blood-thinning compounds" were supposed to be acting on.

Incidentally, the article does not provide references so BFTF cannot check the cited papers themselves, but the German study may be a follow up to this 2003 investigation and another study points out that investigations in to leech therapy are difficult to perform as the patients inevitably know whether they are being treated by leeches or by another method :

"Leech therapy can reduce symptoms caused by osteoarthritis. Repeated use of the leeches appears to improve the long-term results. We have not determined whether the positive outcome of the leech therapy is caused by active substances released during the leeching, the placebo effect, or the high expectations placed on this unusual treatment form"

NSB can find no reference in the online medical database PubMed for the use of leeches to cure migraines. In fact, internet references seem to largely relate to the MainOnline article itself.

So, in summary, there seems to be no evidence for the efficacy of leeches to treat migraines, not is any plausible explanation for their mechanism of action offered.

b) Wide ranging claims are made
It always makes NSB suspicious when wide ranging claims are made with no evidence for their efficacy. In this case, Bowles comments that :

"Google led me to Alicja, a Russian/Polish hirudotherapist [leech therapist] with ten years’ experience. She is based in Las Vegas and New York but she has clients from all around the world. She says the secretions from leeches’ saliva can be used to treat the entire spectrum of physiology: blood-clotting, digestion, connective tissue, disease, pain, inhibition of enzymes, and as a treatment for inflammation."

c) No evidence that the procedure worked even in this case
Bowles states that

"I could go for six months without suffering [a migraine], then there would be a whole week of agony"


and that she has not had a migraine since the leech therapy. As the leech therapy appears to have been performed this year (2013) and that the date of the article is 1st June, it is not clear that the frequency of migraines has changed for Bowles.

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