(n.) The central or topmost stone of an arch. This in some styles is made different in size from the other voussoirs, or projects, or is decorated with carving. See Illust. of Arch.
Example Sentences:
(1) If these is the case the Ir gene (genes) would be the Keystone for maintaining the preferential associations of some pseudoalleles in some haplotypes.
(2) Oil carried by Keystone will displace heavy crude from Venezuela, Nigeria and other countries that also contribute to global warming, Pourbaix said.
(3) The bill, voted through a panel of the house energy and power subcommittee, would compel Obama to over-rule demands for a further review of the project from the Environmental Protection Agency (EPA), and disregard local opposition to the Keystone XL pipeline from landowners along its 1,700-mile route.
(4) But two key Liberal positions, on the Keystone XL and on emissions reductions targets, put Trudeau out of step with Obama, who has made climate change the signature issue of his second term in the White House.
(5) Former hedge fund manager Tom Steyer took out television ads on Tuesday, the night of Obama's state of the union address , attacking Keystone XL, and other wealthy Democratic donors wrote open letters to the White House seeking to shut down the project.
(6) Now that the State Department has just released a final environmental impact report on Keystone XL, which appears to downplay the threat, and greatly increases the odds that the Obama administration will approve the project, I feel I must weigh in once again.
(7) Environmental activists opposed to the Keystone XL tar sands pipeline project protest outside the White House in Washington.
(8) On the campaign trail, however, Clinton had claimed it would be inappropriate to express her views on Keystone given her recent service in Barack Obama’s administration.
(9) The system should include two prehospital and two hospital levels, and the highest level being the keystone of the whole.
(10) A Nebraska court has signed off on the proposed route for the Keystone XL, bringing the controversial project a crucial step closer to reality after six years of legal and political fighting.
(11) The choice President Obama has faced in recent weeks – whether to approve the Keystone XL pipeline – has been framed as a choice between losing the support of environmentalists or alienating America's key ally, Canada.
(12) The company behind the Keystone XL pipeline has asked for its US permit application to be put on hold – a move that would leave the final decision on the controversial tar sands oil project to Barack Obama’s successor.
(13) What makes the Keystone XL pipeline different is the scale – and politics.
(14) One way TransCanada might get around what Clinton called the Keystone “distraction” and pump more tar sands crude into the US might be the Upland pipeline, which the Natural Resources Defense Council (NRDC) has termed a “mini Keystone” .
(15) The virions of CE group viruses (CE, Jamestown Canyon, Keystone, LAC, Melao, SSH, TVT, TAH viruses and South River, an unregistered virus) have three major viral polypeptides, designated G1, G2, and N.
(16) And we saw the Assad regime as the keystone in that arc.
(17) We look forward to the debate and ultimately a decision by the US administration to build Keystone XL,” the company said in a statement.
(18) Greenpeace UK energy campaigner Louise Hutchins said: “The pledge to end dirty coal that David Cameron seems to have casually dropped from his summit speech wasn’t just a footnote but the keystone of any serious policy to clean up Britain’s energy system.
(19) Also speaking at the fossil fuel conference in Houston, ExxonMobil chairman and chief executive Rex Tillerson called for the exploitation of Arctic oil and gas reserves and the building of the Keystone XL pipeline to bring oil from Canada’s tar sands to the US.
(20) This is absolutely not in our national interest.” The campaign against Keystone XL has become a national movement over the last three years, with environmental activists, Nebraska landowners and hedge fund managers all coming out against the project.
Sagitta
Definition:
(n.) A small constellation north of Aquila; the Arrow.
(n.) The keystone of an arch.
(n.) The distance from a point in a curve to the chord; also, the versed sine of an arc; -- so called from its resemblance to an arrow resting on the bow and string.
(n.) The larger of the two otoliths, or ear bones, found in most fishes.
(n.) A genus of transparent, free-swimming marine worms having lateral and caudal fins, and capable of swimming rapidly. It is the type of the class Chaetognatha.
Example Sentences:
(1) In addition, we report a new type of photoreceptive cell in mesopelagic Sagitta zetesios, in which two receptoral processes emerge from single cells, in contrast to one in all the other species of Sagitta.
(2) The presumed photoreceptive region of the arrow-worms of the species Sagitta crassa and Spadella schizoptera consists of perforated lamellae which are unique as the photoreceptive structure.
(3) The sagittae of tire- and barrel-form toric surfaces differ off the principal meridians, as is shown by a numerical example.
(4) The exact equation for sagitta of spherical surfaces is generalized to toric surfaces which include spherical and cylindrical surfaces as special cases.
(5) The experience gathered in the correction of sagittal mandibular over- and under-development allows to make the following conclusions:--In the choice of osteotomy it is necessary that careful consideration be given not only to the proportions of the body and ramus of the mandible, but also to the angular interrelationships of mandibular bones.--Osteotomies in the body of the mandible are indicated especially in those cases where it is only necessary for parallel shifts to be made in the sagittal plane.--Osteotomies performed in the region of the angle of the mandible and the ramus of the mandible (Obwegeser-Dal Pont) enable both longitudinal compensation or adjustment in the sagitta.
(6) Generalized equations are derived for sagitta and lens thickness for surfaces of any form.
(7) The value of the second fundamental form is approximately double the sagitta.
(8) The gerbils' fleas are more abundant on D. sagitta than on the other species.
(9) Under study was the histological structure of the adrenal of the gopher Spermophilopsis leptodactylus L., jerboa Dipus sagitta Pall.
(10) A survey of the eye structure in 10 species of Sagitta (phylum Chaetognatha) which differ in habitat was carried out: 5 epipelagic, 4 mesopelagic and 1 bathypelagic species.
(11) A general routine exists for estimating dioptric power from any number of measurements of sagitta, lens thickness, meridional curvature or power, and prismatic effect.
(12) A method published elsewhere for estimating dioptric power from meridional measurements is generalized here to allow for measurements of sagitta, lens thickness, and prismatic effect as well.
(13) The histology of the Chaetognath's trunk is largely based upon works of Hertwig (1880) and Burfield (1927) and is revised here essentially on ultrastructural basis, in a study on Sagitta setosa.
(14) The existence of a visual pigment in this region was demonstrated by a histofluorescent technique using Spadella schizoptera, whose presumed photoreceptive region was much larger than in Sagitta crassa.
(15) 2) From the hemodynamic change, the progression of rapid increase of cerebral blood volume with increase of blood volume in the superior sagitta sinus during cerebral vasoparesis under intracranial hypertension is presumed.
(16) In four species, the sagitta exhibited a multifluted anterior part and a tapered posterior part; in Corydoras aeneus, however, the fluted part was absent, and a vertical component extended dorsally to terminate near the opening of the transverse canal.