Category Archives: Science

Science Week: Earthquakes in Italy

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This post was contributed by Bryony Stewart-Seume, of Birkbeck’s Department of Biological Sciences.

Professor Gerald Roberts

Professor Gerald Roberts. Photo: Harish Patel

Science Week continued with a popular lecture about the widespread damage and complicated scientific questions arising from earthquakes.

Professor Gerald Roberts, of Birkbeck’s Department of Earth and Planetary Sciences, delivered a talk, entitled Earthquakes in Italy: the role of the historical record of earthquakes and geology, on 18 April. He began with a little history. The 1915 Avezzano earthquake killed a reported 30,000 people, and destroyed all but one building.

On  6 April 2009 an earthquake with its epicentre close to the town of L’Aquila in central Italy killed “only” 309 people. However, 30-50 per cent of the buildings in the town were badly damaged or razed to the ground, including a halls of residence in which eight students lost their lives. To better get an idea of the extent of the damage to the town (the centre of which has still not been repopulated), Prof. Roberts asked us to imagine half of the city of Bath being damaged beyond repair.

In an unfortunate twist the Town Hall of L’Aquila, which contained plans for dealing with such situations, was also badly damaged. Several 13-15th century cathedrals and churches were damaged and part of the modern hospital fell into the underground car park below it. The older masonry buildings proved especially vulnerable.

The financial cost of the 2009 earthquake has been estimated at €16 billion .

Scientists in the dock
There is, however, more to the story of the L’Aquila earthquake of 2009 than damage and a number of deaths. Prior to the earthquake citizens concerned by a number of tremors that had been rocking the city called upon the National Commission for the Forecast and Prevention of Major Risks to give an idea of the potential danger. What followed was unfortunate, in that initially the answer was along the lines of “it is not possible to predict earthquakes but this area has a long history of earthquakes and you should be vigilant”; a correct statement, but subsequently one of the members said in a TV broadcast that there was “no danger” which was not correct. 

When the earthquake did hit, police had reportedly told people that as there was “no danger” they should return to their houses. Seven members of the National Commission were subsequently tried, and convicted, for involuntary manslaughter. Their conviction was met with disgust by parts of the scientific community, although it was stated by the judge that it was not science that was judged, or the inability to predict an earthquake, but the failure to communicate consistently. This highly controversial conviction has led to concern amongst scientists about the future for those studying and communicating earthquake science.

So what can be done about this? Earthquakes will not stop happening. The African plate will not stop pushing into the plate containing Italy. And Italy will not stop being pulled apart. So how can we better communicate what we do know, and what we can do?

Asking the right questions
The question “when will there be an earthquake here?” is not one that can be answered. When an earthquake happens along any given fault is unpredictable. That an earthquake will happen along any given fault is inevitable. Earthquakes are caused by the movement of the plates of the Earth’s crust. Professor Roberts demonstrated through use of a model with springs and metal blocks moving on a sandpaper surface just how chaotic the movement is. The elastic crust pulls apart (or pushes together), tension builds up and the ‘elastic’ releases. This is what causes the earthquake itself. 

Professor Roberts took us through a more useful series of questions that populations should be educated to ask rather than the standard “when” question, the first being; does my area have a history of earthquakes. If you happen to live in central Italy the answer is obviously and demonstrably “yes”.

The next question that should be asked is; do I live in an earthquake zone? If you live near to an active fault, the short answer is “yes, you do.” But how active is it? How can that be measured? The question to ask here is “how much has the fault shifted, and how quickly?” This is measurable, believe it or not, with the help of supernovae – burnt out and blown up stars that send out high energy particles that react when they hit calcium, for example in limestone around L’Aquila to produce new 36Cl atoms. 

Professor Roberts stressed that although earthquakes cannot be predicted, in areas containing active faults they are inevitable and this needs to be communicated to populations.

The more time that elapses between each earthquake the more tension builds up and therefore the bigger the quake will be when it does happen. Which it will. They are inevitable, but not predictable.

Given that it is the building that kills you, not the earthquake itself, the best way to prepare for a quake is to make sure your buildings will take the strain. Buildings made out of cubes are weak and no match for the ferocity of  nature. But if you reinforce the buildings with struts to make triangles in corners, you will improve the integrity straight away.

There is, therefore, a need to educate populations about the right questions to ask and about the significance of small tremors. These questions should be asked many years in advance to ascertain whether earthquakes are inevitable in the area they inhabit and how they can undertake actions to prepare buildings to withstand the seismic shaking.

Just because there has not been an earthquake for a long time does not mean that you are safe. In fact, quite the opposite. All this needs to be conveyed, but without being alarmist.

Science Week: Sex, drugs and rock n’ roll

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Chlamydia: unlocking the secrets of a stealth pathogen

Dr Richard Hayward – a Royal Society University Research Fellow and a member of the Institute of Structural Molecular Biology at Birkbeck/UCL – presented his group’s latest findings on Chlamydia on 17 April during Science Week.

Professor Nick Keep and Dr Richard Hayward

Dr Richard Hayward (right) and Professor Nick Keep. Photo: Harish Patel

Dr Hayward started with an overview of bacteria, explaining that most bacteria are good so-called commensal bacteria that coexist alongside us fine. Indeed our bodies contain more bacterial cells than human cells. Some bacteria can be bad when we are weakened and there is opportunist infection. A few bacteria are always BAD, these are the pathogens such as the bacteria that cause TB. These pathogenic bacteria secrete toxins or, as in the case of Chlamydia, have developed a syringe like mechanism to inject proteins into host cells. Dr Hayward also compared the parts of both a bacterial cell and human cell to parts of a town – the power station, the waste dump and so on.

He then focussed on Chlamydia, which is the most common sexually transmitted disease. Often infections are not noticed, but even these can lead to infertility. Chlamydia infection is also associated with pelvic inflammatory disease and cancer in women. He turned to the effect on men towards the end of the talk, where his own research in collaboration with Addenbroke’s Hospital in Cambridge has shown that Chlamydia bacteria can enter sperm and will almost certainly therefore impact on male fertility.

The National Screening Programme for Chlamydia has unfortunately had a limited effect in reducing infection according to a National Audit Office report. Persuading teenagers to reduce their sexual activity has proved to be difficult. Perhaps development of a vaccine will be a more productive approach.

In the third world Chlamydia, however, is the cause of blindness by trachoma, which is an eye infection spread by touch between family members rather than a sexually transmitted disease. The WHO S.A.F.E. programme (Surgery, Antibiotics, Facial cleanliness and Environmental change – access to clean water) is starting to positively impact on this form of infection.

The core of Dr Hayward’s was his group’s own research on looking at Chlamydia. Chlamydia is hard to study as it cannot be grown in liquid or plate culture, it can only be grown in cell lines. There are also no systems to manipulate its genetics. It has two stages of its life cycle – elementary bodies and reticulate bodies. These had led to a debate only recently resolved as to whether Chlamydia was a bacteria, virus or parasite.

Dr Hayward showed some beautiful pictures and movies using fluorescence microscopy, confocal microscopy and electron tomography, which have shown for the first time the interactions between Chlamydia and the host cell in great detail. It was even possible to just about see the needle injection apparatus of the bacteria actually penetrating the host cell. These new insights into the infection cycle show up possible places to target to counter this complex infection. Dr Hayward did an excellent job in explaining what we know and what we still need to find out.

Science Week: The latest findings in autism research

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This post was contributed by Guy Collender, of Birkbeck’s Department of External Relations.

ProfessorMichaelThomas400, of Birkbeck's Department of Psychological Sciences

Professor Michael Thomas shared the latest autism research during Science Week. Photo: Harish Patel

The media spotlight never seems to be far away from autism, and interest in the developmental disorder has been reignited by the measles outbreak in Swansea. The discredited research linking the MMR vaccine and autism is in the news again, and other debates about autism abound – what causes it?, how early can it be diagnosed?, and how can it be treated?

In light of these controversies and unanswered questions, it was not surprising that a packed lecture theatre awaited the thoughts of Professor Michael Thomas when he delivered his talk about autism on 17 April during Birkbeck’s Science Week. Grabbing the last seat on the back row, I joined the audience and found it refreshing to hear a considered and comprehensive assessment of the spectrum disorder that affects how a person communicates with, and relates to, other people. The talk helped separate fact from fiction and explored an interesting new hypothesis about the cause of autism too.

Professor Thomas, of Birkbeck’s Department of Psychological Sciences, explored the different causal explanations of autism. He described how genes play the major role, but that most cases involve a mixture of common variants (not mutations) and that genetic explanations do not tell the whole story. For example, Professor Thomas said that an identical twin has a 60-90 per cent chance of developing autism if the other twin is affected by the disorder. Therefore, environmental factors must play a role in determining whether a child develops autism as if genes were wholly responsible the figure would be 100 per cent. He also highlighted how the severe deprivation experienced by children in Romanian orphanages caused around 10 per cent of these children to show quasi-autism.

Birkbeck research
Referring to recent Birkbeck research, Professor Thomas explained that changes in brain activity among babies can be detected and are able to predict whether a child will develop autism. Ongoing work at Birkbeck as part of the British Autism Study of Infant Siblings (BASIS) Network is investigating these early months, and early behavioural indicators of autism are being identified at 12 months.

Professor Thomas mentioned screening for autism, but indicated that this isn’t yet a realistic prospect because of the costs involved, concerns about the accuracy of the diagnosis, and what happens after diagnosis. For instance, if autism can be diagnosed, but effective interventions do not exist, then how helpful is a test? Earlier in the lecture, he referred to interventions and stressed that where they are effective they need to be sustained and intense. Research has shown that the most promising approach is early intensive behavioural intervention, which needs to start before age two and be carried out for at least 40 hours per week over two years.

New hypothesis
Professor Thomas also set out a new hypothesis regarding the cause of autism. He explained how connections within the brain are ‘pruned’ in early and middle childhood as unused connections, which are expensive for the body to maintain, are cut away. The pruning hypothesis proposes that this natural process malfunctions in children with autism. Instead of just cutting unnecessary connections, exaggerated pruning means functional connections within the brain are cut. In some children this occurs slightly later, allowing normally looking early behaviour followed by the loss of acquired skills during the second year of life. In other children, exaggerated pruning in the first year leads to atypical development after the first few months of life. The hypothesis predicts that such pruning should affect the sensory and motor systems first, and home videos of infants with autism recorded at four or six months do show some anomalous movements.

The complexities of autism were clearly made throughout the presentation, but what was also clear is that more and more research is leading to a greater understanding of autism and is likely to lead to earlier and earlier diagnosis of the disorder.

Science Week: Piecing together the jigsaw of climate change and human evolution

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This post was contributed by Guy Collender, of Birkbeck’s Department of External Relations.

Dr Phil Hopley, of Birkbeck's Department of Earth and Planetary Sciences

Dr Phil Hopley exhibited replica skulls of our ancestors during Science Week. Photo: Harish Patel

I knew an unusual presentation was in store as soon as I saw six skulls menacingly positioned at the front of the lecture theatre. The exhibits – all different shapes and sizes – immediately caught the audience’s attention, and our questions about their origins were answered in the fascinating hour that followed.

Dr Phil Hopley began Birkbeck’s series of Science Week lectures with a talk on 16 April about the links between climate change and human evolution. He used the skulls – five replicas of our ancestors and one gorilla skull – to illustrate how evolution is all about the changing dimensions of the head as it has become rounder and larger to accommodate a bigger brain over millions of years. In comparison, the gorilla’s skull includes ferocious canines and space for huge powerful jaws – it certainly sent a shiver up my spine being only a few feet away from my seat.

A family tree dating back millions of years
Dr Hopley, of Birkbeck’s Department of Earth and Planetary Sciences, explained how the last common ancestor of chimpanzees and modern humans was on this planet about six of seven million years ago. Both branches of the family tree then developed separately, with chimpanzees on the one hand, and about 20 species of hominins – the ancestors of modern humans – walking on two legs on the other. As the hominins evolved, they became characterised by their tool use, larger brains, language and art, eventually developing into Homo sapiens – our own species. But our ancestral line has not been straightforward, and Dr Hopley highlighted the complexity. He said: “Homo sapiens is the only human species alive today, but for most of human evolution there have been a number of co-existing human species.”

As Dr Hopley explained, hominin fossils have mainly been found in two areas – the Rift Valley in East Africa (dating back five million years), and caves in Southern Africa (dating back 2.5 million years). Yet, hardly surprising, given the awesome amount of time involved, it is very rare to find a whole hominin specimen. What is clear is that the human fossil record is very incomplete, both geographically and temporally, and solving the mystery is a bit like piecing together a jigsaw.

Climate change: from forest to grassland
The question of why our ancestors evolved to become bipedal was then addressed, and this was where Dr Hopley referred to his work studying fossils from caves in South Africa. The study of carbon and oxygen isotypes and climate modelling has shown that the savannah in Africa developed eight million years ago due to the reduction in carbon dioxide and reduction in rainfall. As the grasslands replaced the forests, our ancestors evolved to walk on two feet as they needed to cover large distances to search for food, which wasn’t necessary when they were still living in the forest. Although it’s difficult to build up a comprehensive understanding of how climate change drives evolution, Dr Hopley did present a general conclusion. He said: “Human evolution did occur because of climate change in the broad sense as forests were replaced by savannah.”

I’ve never been to a lecture with skulls on display before and I’ll certainly never forget this one. It was a powerful way to remind us that our common ancestors adapted to the African bush and started walking when the forests began to recede.