Beverley Brook is a minor English river 14.3 km long in southwest London. It rises in Worcester Park and joins the River Thames to the north of Putney Embankment at Barn Elms. Beverley Brook rises at the top of a hill in a shady area at Cuddington Recreation Ground in Worcester Park flows north in a culvert under the A2043 road, emerging in waste land next to Worcester Park Station, it flows northeast through Motspur Park, New Malden, Wimbledon Common, Richmond Park, forms the brief boundary of East Sheen and Roehampton near Priest's Bridge, flows through the south of Barnes and joins the River Thames above Putney Embankment at Barn Elms, Barnes. Its basin has a catchment area of 64 km2. Beverley Brook creates a water feature used by deer, smaller animals and water grasses and some water lilies in Richmond Park. For the next 7 km upstream of Richmond Park, the Beverley Brook forms the historic South West London boundary, now the boundary between the London Borough of Merton and the Royal Borough of Kingston upon Thames.

For the first 5 km south of Richmond Park, the six lane A3 trunk road from London to Portsmouth runs always within 300 m of the stream, crossing it three times. Although there is no point where the stream itself can be seen when driving along the road, the bridge parapets are visible and, for 2 km, where the road runs along the edge of Wimbledon Common, the trees flanking the stream can be glimpsed across playing fields, with the managed "natural" woodland of the common rising beyond. Except for the playing fields, the whole of the common, including Beverley Brook, is both a Site of Special Scientific Interest and a Special Area of Conservation. Towards the south end of the common, Fishpond Wood and Beverley Meads nature reserve lies a few metres east of the stream. South of Wimbledon Common the stretch of the A3 running near the stream is named Beverley Way after it; the name is derived from the former presence in the river of the European beaver, a species extinct in Britain since the sixteenth century.

The Middle English word for beaver was bever, the word for meadow was ley and brook meant stream, as it does today. Beverley Brook was thus the Beaver-Meadow Stream. Beverley Brook's longest tributary is Pyl Brook, 5.3 km long, a Local Nature Reserve. It flows from Sutton through Lower Morden to join it at Beverley Park in New Malden. Both brooks are on the Environment Agency's watchlist of rivers susceptible to flooding. For much of the twentieth century Beverley Brook was joined by poorly treated sewage from a sewage works in Green Lane, Worcester Park. Since some pipe redirection enabling the removing of the works and the introduction of improved treatment methods in 1998, the range of wildlife species in the river has increased. At Wimbledon Common, Beverley Brook has banks reinforced with wooden "toe-boarding", which prevents use by water voles. and there is scope for further such improvements. Beverley Brook is a regular character in the Ben Aaronovitch series of urban fantasy police procedurals Rivers of London.

She describes her kind thus: "'Orisa', said Beverley.'We're Orisa. Not spirits, not local geniuses – Orisa'." Tributaries of the River Thames List of rivers of England Beverley Brook Catchment Royal parks press release on the improving water quality of the river The Beverley Brook waymarked walk Beverley Brook Walk Beverley Brook Walk map Flow measurements

Claudins are a family of proteins which, along with occludin, are the most important components of the tight junctions. Tight junctions establish the paracellular barrier that controls the flow of molecules in the intercellular space between the cells of an epithelium, they have the C-terminus in the cytoplasm. Claudins are small transmembrane proteins which are found in many organisms, ranging from nematodes to human beings, are similar in their structure, although this conservation is not observed on the genetic level. Claudins span the cellular membrane 4 times, with the N-terminal end and the C-terminal end both located in the cytoplasm, two extracellular loops which show the highest degree of conservation; the first extracellular loop consists on average of 53 amino acids and the second one, being smaller, of 24 amino acids. The N-terminal end is very short, the C-terminal end varies in length from 21 to 63 and is necessary for the localisation of these proteins in the tight junctions, it is suspected that the cysteines of separate claudins form disulfide bonds.

All human claudins have domains. Claudins were first named in 1998 by Japanese researchers Mikio Furuse and Shoichiro Tsukita at Kyoto University; the name claudin comes from Latin word claudere. A recent review discusses evidence regarding the structure and function of claudin family proteins using a systems approach to understand evidence generated by proteomics techniques. In humans, 24 members of the family have been described. CLDN1, CLDN2, CLDN3, CLDN4, CLDN5, CLDN6, CLDN7, CLDN8, CLDN9, CLDN10, CLDN11, CLDN12, CLDN13, CLDN14, CLDN15, CLDN16, CLDN17, CLDN18, CLDN19, CLDN20, CLDN21, CLDN22, CLDN23 Occludin

The Siege of Kyiv by the Pechenegs in 968 is documented in the Primary Chronicle, an account that mixes historical details with folklore. According to the chronicle, while Svyatoslav I of Kyiv was pursuing his campaign against the First Bulgarian Empire, the Pechenegs invaded Rus and besieged his capital of Kyiv. While the besieged suffered from hunger and thirst, Svyatoslav's general Pretich deployed his druzhina, his personal guard, on the opposite bank of the Dnieper, not daring to cross the river against the larger Pecheneg force. Reduced to extremes, Svyatoslav's mother Olga of Kyiv contemplated surrender if Pretich did not relieve the siege within one day, she was anxious to send word about her plans to Pretich. At last a boy fluent in the Pecheneg language volunteered to venture from the city and urge Pretich to action. Pretending to be a Pecheneg, he went about their camp; when he attempted to swim across the Dnieper, the Pechenegs discovered his subterfuge and started shooting at him, but to no avail.

When the boy reached the opposite bank and informed Pretich about the desperate condition of the Kyivans, the general decided to make a sally in order to evacuate Svyatoslav's family from the city, for fear of his sovereign's anger. Early in the morning Pretich and his troops embarked on boats across the Dnieper, making great noise with their trumpets; the besieged started Olga ventured out of the city towards the river. The Pechenegs, lifted the siege; the Pecheneg leader decided to confer with Pretich and asked him whether he was Svyatoslav. Pretich admitted that he was only a general but warned the Pecheneg ruler that his unit was a vanguard of Svyatoslav's approaching army; as a sign of his peaceful disposition, the Pecheneg ruler shook hands with Pretich and exchanged his own horse and arrows for Pretich's armor. As soon as the Pechenegs retreated, Olga sent a letter to Svyatoslav reproaching him for his neglect of his family and people. Upon receiving the message, Svyatoslav speedily returned to Kyiv and defeated the Pechenegs, who were still threatening the city from the south.

The following year Olga died and Svyatoslav moved his capital from distant Kyiv to Pereyaslavets in present-day Romania. Vasily Vasilievsky. Byzantium and the Pechenegs. St. Petersburg, 1872