(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.
Mask
Definition:
(n.) A cover, or partial cover, for the face, used for disguise or protection; as, a dancer's mask; a fencer's mask; a ball player's mask.
(n.) That which disguises; a pretext or subterfuge.
(n.) A festive entertainment of dancing or other diversions, where all wear masks; a masquerade; hence, a revel; a frolic; a delusive show.
(n.) A dramatic performance, formerly in vogue, in which the actors wore masks and represented mythical or allegorical characters.
(n.) A grotesque head or face, used to adorn keystones and other prominent parts, to spout water in fountains, and the like; -- called also mascaron.
(n.) In a permanent fortification, a redoubt which protects the caponiere.
(n.) A screen for a battery.
(n.) The lower lip of the larva of a dragon fly, modified so as to form a prehensile organ.
(v. t.) To cover, as the face, by way of concealment or defense against injury; to conceal with a mask or visor.
(v. t.) To disguise; to cover; to hide.
(v. t.) To conceal; also, to intervene in the line of.
(v. t.) To cover or keep in check; as, to mask a body of troops or a fortess by a superior force, while some hostile evolution is being carried out.
(v. i.) To take part as a masker in a masquerade.
(v. i.) To wear a mask; to be disguised in any way.
Example Sentences:
(1) The blocking action may have masked and hindered detection of the stimulatory action of barium in other systems.
(2) Masking experiments are demonstrated for electrical frequency-modulated tone bursts from 1,000 to 10,000 cps and from 10,000 to 1,000 cps with superimposed clicks.
(3) Though immunocytochemistry did not show staining of synaptic regions this may be due to masking of the reactive epitope.
(4) Such factors can mask any interactions between biologic factors of the aging female reproductive system and other social factors that might otherwise detemine fertility during the later reproductive years.
(5) The interresponse-time reinforcement contingencies inherent in these schedules may actually mask the effects of overall reinforcement rate; thus differences in response rate as a function of reinforcement rate when interresponse-time reinforcement is eliminated may be underestimated.
(6) In gastric cancers the major finding was the occurrence of extensive masking of lectin binding sites by sialic acid which was not seen in normal mucosa.
(7) The expression of such secondary and tertiary syphilis is commonly masked and distorted by the long-term effects of subcurative doses of antibiotics; in fact, late latent and tertiary syphilis produce symptoms and immunosuppression similar to the profile of AIDS.
(8) After induction of anesthesia, the airway of those in group A was maintained with a conventional tracheal tube; in group B, with a laryngeal mask airway.
(9) To determine if the type of mechanical ventilation used (ie, face mask, nasal prongs, or endotracheal tube) was associated with GPNN, a matched case-control analysis was performed.
(10) Data were analyzed by investigators who were masked to treatment assignment or phase of study.
(11) The air entrainment devices from oxygen masks of four manufacturers (Henleys Medical Supplies Ltd, Vickers Medical, Intersurgical Ltd, C R Bard International Ltd) were studied.
(12) North Korea's blustering defiance at the annual US-South Korean exercises masks just a little fear that they could easily be turned into an all-out attack, and seems to work on the principle that the more you shout, the safer you will be.
(13) Since headache can often represent the warning symptom of a masked depression, in the present study sulpiride has been administered to patients suffering from nonorganic headache syndromes.
(14) • Police would be given discretion to remove face masks from people on the street "under any circumstances where there is reasonable suspicion that they are related to criminal activity".
(15) Analyses of this artificial curve allow estimation of that part of the internal interactions uninfluenced by the masking effect.
(16) Compared to previous masking studies of orientation selective units, non-oriented units have somewhat broader spatial frequency sensitivity curves, in agreement with primate neurophysiology.
(17) The contralateral masked condition was performed using 30-dB-SL 400-Hz narrow-band masking noise centered at frequency of test tone.
(18) But the research drills down into the data to examine different cohorts separately, and discovers that reassuring overall averages are masking some striking variations.
(19) Older subjects were found to be significantly more susceptible to the backward masking effect over longer delays between the target and masking stimuli.
(20) We have compared an alternative breathing system for preoxygenation comprising a Hudson face mask with high oxygen inflow (48 litre min-1) and a Mapleson A breathing system (100 ml kg-1 min-1).