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In early 2014 Crimea became the focus of the worst East-West crisis since the Cold War, after Ukraine's pro-Moscow president Viktor Yanukovych was driven from power by violent protests in Kiev. Kremlin-backed forces seized control of the Crimean peninsula, and the territory, which has a Russian-speaking majority, voted to join Russia in a referendum that Ukraine and the West deem illegal. Crimea was annexed by the Russian Empire during the reign of Catherine The Great in 1783 and remained part of Russia until 1954, when it was transferred to Ukraine under the then Soviet leader Nikita Khrushchev. Ethnic Russians make up the majority of the population, but with significant Ukrainian and Crimean Tatar minorities. Under Greek and Roman influence for centuries, in 1443 Crimea became the centre of a Tatar Khanate, which later fell under Ottoman control. Rival imperial ambitions in the mid 19th century led to the Crimean War when Britain and France, suspicious of Russian ambitions in the Balkans as the Ottoman Empire declined, sent troops. Given autonomous republic status within Russia after the Bolshevik revolution, Crimea was occupied by the Nazis in the early 1940s. Tatar deportation Stalin accused the Tatars of collaborating with the German occupiers and deported them en masse to Central Asia and Siberia in 1944. Many did not survive. Only as the Soviet Union collapsed were they allowed to return. By the time over a quarter of a million did so in the early 1990s, it was to an independent Ukraine where they faced very high unemployment and extremely poor housing conditions. There were persistent tensions and protests over land rights, and allocation of land to Crimean Tatars was a contentious issue. After Ukrainian independence, political figures from the local Russian community sought to assert sovereignty and strengthen ties with Russia through a series of moves declared unconstitutional by the Ukrainian government. The 1996 Ukrainian constitution stipulated that Crimea would have autonomous republic status, but insisted that Crimean legislation must be in keeping with that of Ukraine. Crimea has its own parliament and government with powers over agriculture, public infrastructure and tourism. The Crimean Tatars have their own unofficial parliament, the Mejlis, which states its purpose as being to promote the rights and interests of the Crimean Tatars. Ukraine-Russia tension The port of Sevastopol is a major naval base and has been home to the Black Sea Fleet since 1783. Following the collapse of the USSR, the fleet was divided up between Russia and Ukraine. The continuing presence of the Russian fleet in Sevastopol has been a focus of tension between Russia and Ukraine. In 2008, Ukraine - then under the pro-Western President Viktor Yushchenko - demanded that Moscow not use the Black Sea Fleet during the its conflict with Georgia. Both countries had agreed to allow the Russian fleet to stay until 2017, but after the election of the pro-Russian Viktor Yanukovych as president in 2010, Ukraine agreed to extend the lease by 25 years beyond 2017, in return for cheaper Russian gas.
The Republic of Crimea, officially part of Ukraine, lies on a peninsula stretching out from the south of Ukraine between the Black Sea and the Sea of Azov. It is separated from Russia to the east by the narrow Kerch Strait.

Scans revealed children carrying the gene variant appeared to have more nerve cell "connections" within the frontal lobe. They had fewer connections between this and the rest of the brain, reported Science Translational Medicine journal. Brain research has just begun to reveal autism's roots, a UK expert said. One-third of the population carry the CNTNAP2 gene variant, so it does not guarantee that autism will develop, but just slightly increases the risk. Different pathways However, scientists at the University of California in Los Angeles believe it may influence the way the brain is "wired". They used functional magnetic resonance imaging (fMRI) to look for communication between different brain regions, and to measure the strength of these connections. They scanned the brains of 32 children as they performed learning-related tasks - half had autism, and half did not. Regardless of their diagnosis, those carrying the CNTNAP2 variant had differences in the connections within the frontal lobe of the brain itself and between the frontal lobe and the rest of the brain. Dr Ashley Scott-Van Zeeland, who led the research, said: "The front of the brain appears to talk mostly to itself - it doesn't communicate as much with other parts of the brain and lacks long-range connections to the back of the brain." The researchers also spotted differences in the "wiring" between the frontal lobe and the left and right sides of the brain. In children with the version of the gene not linked to autism risk, the pathways were linked more strongly to the left side of the brain. In those with the "risk variant", the pathways were different, linking the lobe strongly to both sides of the brain. This, said the researchers, could explain why the gene variant had been linked to children who are slow in starting to talk. Dr Scott-Van Zeeland said that if the gene variant did predict language problems, then it might be possible to design therapies which helped to "rebalance" the brain and encourage normal development. Professor Margaret Esiri, a neuroscientist from Oxford University, said that researchers had so far "barely scratched the surface" of understanding the interplay between genes and brain development. Her own research closely analyses a scarce supply of donated brains from both autistic and non-autistic adults and children to look for differences in structure and function. She said: "If you understand these subtle differences, there may be ways of 'tweaking' them earlier in life, and bringing them back into a normal trajectory of development. Of course, this would be many years away." Carol Povey, from the National Autistic Society, said the study was interesting because it began to link genes thought to be involved in autism to actual changes in brain function. She said: "The causes of autism are as yet unknown, but we do know there are likely to be many factors involved, so we hope this will contribute to our understanding of this complex condition."
Differences in the brain structure of people carrying an "autism gene" may offer clues to how the condition develops, say US scientists.

By Reality Check teamBBC News Since 2014, the number of A-level entries in arts subjects, which include drama, music and art, in England has fallen by 13,000, almost 17%. Similarly, there has been an 8% decrease in modern languages and more than a 25% decline in English. Meanwhile, entries in science, technology, engineering and maths (known as Stem subjects) have increased by 15,500, a rise of 6%. Subjects do go in and out of fashion - but to what extent have policy changes had an impact? 'Important' subjects Jon Andrews, deputy head of research at the Education Policy Institute, says the recent decrease in arts entries at A-level is likely to be linked to similar declines seen at GCSE. He says recent changes in school performance measures in England have pushed students away from arts subjects, in favour of ones the government wants prioritised. These include Progress 8 and the linked English Baccalaureate (EBacc), introduced by the Department of Education in 2010. The EBacc system encourages the grouping of subjects that the government says are "important" for students to study at GCSE, with schools measured by how many take a combination that must include: Similarly, Progress 8, established in 2016, assesses a student's progress on eight subjects: Since the introduction of these measures, there has been an increase in all EBacc subjects at GCSEs (except for modern languages) - and this has widened the pool for their uptake at A-level. And there has been a decrease in entries to subjects not explicitly mentioned by the policy, such as economics, religious studies, physical education and the arts. Progress 8 does leave room for arts subjects under the "other" category and the government says that the proportion of pupils taking at least one art subject at GCSE has remained broadly stable. However, the Education Policy Institute disputes this, arguing that by limiting subject slots that can be filled by non-EBacc subjects, arts subjects are being squeezed out. Its analysis shows the proportion of pupils taking at least one arts subject fell from 57.1% in 2014 to 53.5% in 2016 - and with more schools adopting the EBacc measures, this trend may continue. Overall, the number of entries for arts GCSEs has decreased by 30,000. Reforms criticised The reforms came with major changes to course syllabuses in England, including GCSE English, which were aimed at making the subjects tougher. The Association of School and College Leaders (ASCL) has called the reforms "a joyless slog", with pressure to memorise more quotes from a narrower field of texts. They believe that this is part of the reason for the decline in English A-Levels. The government points out that English still remains one of the most popular subjects and argue that "the reformed GCSEs in English are better preparing pupils for further study at A-level." Decoupling of A-Levels The recent separation - or decoupling as it's known - of AS-levels and A-levels in England could also be a factor. "Students may previously have done three A-Levels plus one AS-level and may have done an arts subject as their additional subject," says Jill Stokoe, a policy advisor at the National Education Union. This is speculative, she says, but English A-level uptake has fallen by 20% since the decoupling began in 2017 and a survey by the English and Media Centre (EMC), a charity which supports English education, suggests decoupling has been a key factor in the reduction. This means English might be one of the subjects losing out as result of the limiting of choices at the start of A-levels. The exams and qualifications regulator, Ofqual, says that part of the move away from arts and English is due to the shift to Stem subjects - something the government has actively encouraged. The National Audit Office estimates that between 2007 and 2017, about £990m has been spent on "enhancing Stem skills", both for teachers and pupils. Does it matter? Groups, including the British Council, the Incorporated Society of Musicians and Creative Industries Federation (CIF), have raised concerns over the decrease in arts subjects. The CIF says the exclusion of arts subjects from the EBacc has signalled to schools "that creativity is not fundamental to future skills and jobs". The government says that the creative sector is worth £92bn. Interestingly, there's no indication yet that changes in subject choice in school exams have had a direct impact on university choices. Statistics from the Higher Education Statistics Agency show the proportion of students taking up non-science subjects at university has remained relatively constant. A government official said: "We have reformed A-levels to meet the expectations of universities and employers and our new gold standard GCSEs are more rigorous to match the best education systems in the world, better preparing young people for further study and the workplace." This piece was originally published in August 2018, but has been updated to reflect new data. Read more from Reality Check Send us your questions Follow us on Twitter

In recent years, there has been a clear shift away from the arts, modern languages and some other subjects at both GCSEs and A-levels.

