Telomeres are regions of repetitive DNA at the end of a chromosome, which provide protection from chromosomal deterioration during DNA replication.

Telomeres protect a cell's chromosomes from fusing with each other or rearranging — abnormalities that can lead to cancer — and so cells are destroyed when their telomeres are consumed.

Telomeres are repetitive nucleotide sequences located at the termini of linear chromosomes of most eukaryotic organisms.

Telomeres are normally protected by a " cap " that prevents them from being recognized as double-strand breaks.

He also studied telomeres, and his lab discovered an enzyme, TERT ( telomerase reverse transcriptase ), which is part of the process of restoring telomeres after they are shortened during cell division .< REF > Telomeres, Telomerase, and Other Noncoding RNAs, Howard Hughes Medical Institute, July 13, 2010 </ ref > As president of Howard Hughes Medical Institute, he promoted science education, and he teaches an undergraduate chemistry course at the University of Colorado.

* Telomeres and Telomerase: Their Implications in Human Health and Disease on-line lecture by Elizabeth Blackburn

Of the tumors that have not activated TERT, most have found a separate pathway to maintain telomere length termed ALT ( Alternative Lengthening of Telomeres ).

Telomeres compensate for incomplete semi-conservative DNA replication at chromosomal ends.

Telomeres form large loop structures called telomere loops, or T-loops.

However, 5 – 10 % of human cancers activate the Alternative Lengthening of Telomeres ( ALT ) pathway, which relies on recombination-mediated elongation.

* Harley C, Futcher A & Greider C ( 1990 ) Telomeres shorten during ageing of human fibroblasts, Nature, 345, 458 – 460.

* Wang R, Smogorzewska A & Lange T ( 2004 ) Homologous Recombination Generates T-Loop-Sized Deletions at Human Telomeres, Cell, 119, 355 – 368.

Dominant stress is of course more than extended duration, and normally centers on syllables that would have primary stress or phrase stress if the words or longer units they are parts of were spoken alone: a dominant stress given to glorify would normally center on its first syllable rather than its last.

These studies are being extended to different polymers to increase our knowledge about the hindrances to rotation around chain bonds.

This means that the antennae of the congregation are extended into the community, picking up the wave lengths of those who will fit into the social and economic level of the congregation ; ;

He said his plan is designed to `` meet the needs of those millions who have no wish to receive care at the taxpayers' expense, but who are nevertheless staggered by the drain on their savings -- or those of their children -- caused by an extended hospital stay ''.

Quite clearly the anti-trust laws are neither effective nor rational -- and yet the argument goes that they should be extended to the labor union.

Also, when the patient is standing with arms and hands extended toward the physician, if the eyes are closed, the patient's finger will tend to " fall down " and then be restored to the horizontal extended position by sudden muscular contractions ( the " ataxic hand ").

The " matai " ( chiefs ) are elected by consensus within the fono of the extended family and village ( s ) concerned.

In addition to radar and lightning detection, observations and extended radar pictures ( such as NEXRAD ) are now available through satellite data connections, allowing pilots to see weather conditions far beyond the range of their own in-flight systems.

From the 4th century Christianization of the Roman Empire onwards such shrines, or the framework enclosing them, are often called by the Biblical term tabernacle, which becomes extended to any elaborated framework for a niche, window or picture.

The original thoroughfare, flanked by rows of columns and shops, was about 73 feet ( 22 meters ) wide ( roughly the equivalent of a present-day six lane motorway ), but buildings have extended onto the streets over the centuries, and the modern lanes replacing the ancient grid are now quite narrow.

Temperatures within a given winter are highly variable as well ; extended cold snaps of forty below zero can be followed by unseasonable warmth with temperatures above freezing due to chinook wind effects.

(“ Simple ”) As the extended musical sequence ends, the lights black out except for a spotlight on Hapgood, who announces to the audience, “ You are all mad !” Seconds later, the stage lights are restored.

Urban tram networks exist in Antwerp ( the Antwerp Pre-metro ), Ghent and Brussels ( the Brussels trams ), and are gradually being extended.

In some systems of axiomatic set theory, relations are extended to classes, which are generalizations of sets.

However, they are now increasingly of low-floor design and optionally also ' kneel ' air suspension and have electrically or hydraulically extended under-floor ramps to provide level access for wheelchair users and people with baby carriages.

: Subgroup 2be, with the letter " e " for extended spectrum of activity, represents the ESBLs, which are capable of inactivating third-generation cephalosporins ( ceftazidime, cefotaxime, and cefpodoxime ) as well as monobactams ( aztreonam )

Each hour consists of headlines on each quarter hour, extended at the top of the hour to form the main part of the daily schedule though these are interspaced with other programmes, generally at weekends.

There are also two extended sports bulletins per day, entitled ' Sportsday ' broadcast at 18: 30 and 22: 30 ( weekdays only ).

There are several extant specimens of 12th-century Breviaries, all Benedictine, but under Innocent III ( pope 1198 – 1216 ) their use was extended, especially by the newly founded and active Franciscan order.

In the most common usage, β strand refers to a single continuous stretch of amino acids adopting an extended conformation and involved in backbone hydrogen bonds to at least one other strand ; by contrast, a β sheet refers to an assembly of at least two such β strands that are hydrogen-bonded ( or H-bonded ) to each other.

Ogden's word lists include only word roots, which in practice are extended with the defined set of affixes and the full set of forms allowed for any available word ( noun, pronoun, or the limited set of verbs ).

A pair of Bézout coefficients ( in fact the ones that are minimal in absolute value ) can be computed by the extended Euclidean algorithm.

The place is inhabited by several hundred warlike women who are anachronisms of the Twentieth Century -- stone age amazons who live in an all-female, matriarchal society which is self-sufficient ''.

The two main charges levelled against the Bourbons by liberals is that they are racists and social reactionaries.

to some degree they are being supplanted by a concept of national responsibility.

I asked the same questions inside the launch-control rooms of an Atlas missile base in Wyoming, where officers who wear sidearms are manning the `` commit buttons '' that could start a war -- accidentally or by design -- and in the command centers where other pistol-packing men could give orders to push such buttons.

They are supplied, a batch at a time, by a secret source and are continually changed by Wisman or his staff, at random intervals.

They are huge areas which have been swept by winds for so many centuries that there is no soil left, but only deep bare ridges fifty or sixty yards apart with ravines between them thirty or forty feet deep and the only thing that moves is a scuttling layer of sand.

On Fridays, the day when many Persians relax with poetry, talk, and a samovar, people do not, it is true, stream into Chehel Sotun -- a pavilion and garden built by Shah Abbas 2, in the seventeenth century -- but they do retire into hundreds of pavilions throughout the city and up the river valley, which are smaller, more humble copies of the former.

Those three other great activities of the Persians, the bath, the teahouse, and the zur khaneh ( the latter a kind of club in which a leader and a group of men in an octagonal pit move through a rite of calisthenics, dance, chanted poetry, and music ), do not take place in buildings to which entrance tickets are sold, but some of them occupy splendid examples of Persian domestic architecture: long, domed, chalk-white rooms with daises of turquoise tile, their end walls cut through to the orchards and the sky by open arches.

These are traversed by another line of vaults, and thus rooms, arched on all four sides, are formed.

Nostalgic Yankee readers of Erskine Caldwell are today informed by proud Georgians that Tobacco Road is buried beneath a four-lane super highway, over which travel each day suburbanite businessmen more concerned with the Dow-Jones average than with the cotton crop.

Thus we are compelled to face the urbanization of the South -- an urbanization which, despite its dramatic and overwhelming effects upon the Southern culture, has been utterly ignored by the bulk of Southern writers.

Movements unfold freely because they are uninhibited by emotional bias or purposive drive.

The only factors that are personally set by the choreographer are the movements themselves, the number of the dancers, and the approximate total duration of the dance.

We began by declaring that all men are created equal.

They recognized that slavery was a moral issue and not merely an economic interest, and that to recognize it explicitly in their Constitution would be in explosive contradiction to the concept of sovereignty they had set forth in the Declaration of 1776 that `` all men are created equal, that they are endowed by their Creator with certain unalienable rights, that among them are life, liberty and the pursuit of happiness.

Consitutional government, popular vote, trial by jury, public education, labor unions, cooperatives, communes, socialized ownership, world courts, and the veto power in world councils are but a few examples.

Lucretius has remarked: `` The reason why all Mortals are so gripped by fear is that they see all sorts of things happening in the earth and sky with no discernable cause, and these they attribute to the will of God ''.

I am certainly not adequately trained to describe or enlarge on human fears, but there are certain features of the fears dispelled by scientific explanations that stand out quite clearly.