( Since the time-span of the nation-state coincides roughly with the separate existence of the United States as an independent entity, it is perhaps natural for Americans to think of the nation as representative of the highest form of order, something permanent and unchanging.

Since that time, Alberta's economic fortunes have largely tracked the price of oil, and increasingly natural gas prices.

Since the flow of a baseball game has natural breaks to it, and normally players act individually rather than performing in clusters, the sport lends itself to easy record-keeping and statistics.

Since 1991, Croatia's death rate has continuously exceeded its birth rate ; the natural growth rate of the population is currently negative.

Since society considers so many rights as natural ( hence the term " right ") rather than man-made, what constitutes a crime also counts as natural, in contrast to laws ( seen as man-made ).

A set S is called countable if there exists an injective function f from S to the natural numbers Since there is an obvious bijection between and it makes no difference whether one considers 0 to be a natural number of not.

Since copper metallurgy was already known to have existed in Europe since 7000 BC, with heavy axes of natural bronze produced in bulk since 5500 BC, and since true bronze, made by deliberately alloying copper with tin had already been used in parts of east-central Europe since 3700 BC, Ötzi's axe came as no surprise to archaeologists.

Since his medium for bringing change was print and debate, it was natural for the origins of the Christadelphian body to be associated with journals and books, namely the Herald of the Kingdom and The Ambassador ( which later became The Christadelphian ).

Since 1983, Iraq has repeatedly called for restoration of Egypt ’ s “ natural role ” among Arab countries.

Since then, ecologists have worked to bridge their understanding of the degradation of the planet's ecosystems with environmental politics, law, restoration, and natural resources management.

Since Euclidean space is a metric space it is also a topological space with the natural topology induced by the metric.

Since 2001, economic growth declined caused by adverse shocks such as a slowdown in the global economy and natural disasters.

Since EtBr stained DNA is not visible in natural light, scientists mix DNA with negatively charged loading buffers before adding the mixture to the gel.

Since real political power belongs to the sole legal party, in certain states under Marxist constitutions of the constitutionally socialist state type inspired by the former Union of Soviet Socialist Republics ( USSR ) and its constitutive Soviet republics, there was no formal office of head of state, but rather the leader of the legislative branch was considered to be the closest common equivalent of a head of state as a natural person.

Since 1983, Iraq has repeatedly called for restoration of Egypt ’ s “ natural role ” among Arab countries.

Since 1999, the Isle of Man has received electricity through the world's longest submarine AC cable, the 90 kV Isle of Man to England Interconnector, as well as from a natural gas power station in Douglas, an oil power station in Peel and a small hydro-electric power station in Sulby Glen.

Since its inception it has broadened to find applications in many other areas, including statistical inference, natural language processing, cryptography, neurobiology, the evolution and function of molecular codes, model selection in ecology, thermal physics, quantum computing, plagiarism detection and other forms of data analysis.

Since definitions of left and right based on the geometry of the natural environment are unwieldy, in practice, the meaning of relative direction words is conveyed through tradition, acculturation, education, and direct reference.

Since counter-clockwise may be defined in terms of up, forward, and right, this experiment unambiguously differentiates left from right using only natural elements: If they were reversed, or the atoms spun clockwise, the radiation would follow the spin axis instead of being opposite to it.

Since Macau has little arable land and few natural resources, it depends on mainland China for most of its food, fresh water, and energy imports.

Since the mid-1980s, the donor community, led by the World Bank and the USAID, has recognized that Madagascar is one of the world's most unusual natural wonders.

Since mining entails removing dirt and rock from its natural location creating large empty pits, rooms and tunnels, cave-ins as well as ground and rock falls are a major concern within mines.

Since the Temple was an enclosed place with no natural light, some means of illumination must have existed.

Since this gas is in approximate hydrostatic equilibrium with the overall cluster gravitational field, the total mass distribution can be determined.

Since carbon monoxide is a colorless, odorless and tasteless gas, and poses a potentially fatal threat, detectors have become commercially available to warn of dangerous levels in residences.

Since World War II, Iraq's use of mustard gas against Iranian troops and Kurds ( Iran-Iraq war of 1981 – 1988 ) has been the only large-scale use of any chemical weapons.

Since organic compounds often exist as mixtures, a variety of techniques have also been developed to assess purity, especially important being chromatography techniques such as HPLC and gas chromatography.

Since the collapse of the Soviet Union on 31 December 1991, privately owned Russia-based multinational corporations, including producers of petroleum, natural gas, and metal have, in the view of some analysts, become oligarchs.

Automobile exhaust gas capture has also been proposed to be economical but would require extensive design changes or retrofitting .< ref name = Musadi2011 > Since carbonic acid in seawater is in chemical equilibrium with atmospheric carbon dioxide, extraction of carbon from seawater has been studied.

Since xenon is a volatile noble gas it can be assumed that there wasn't much of it in the rock to begin with.

Since 80 % or more of the oxygen remains in normal exhaled gas, and is thus wasted, rebreathers use gas very economically, making longer dives possible and special mixes cheaper to use at the cost of more complicated technology and more possible failure points.

Since the UNFCCC entered into force, the parties have been meeting annually in Conferences of the Parties ( COP ) to assess progress in dealing with climate change, and beginning in the mid-1990s, to negotiate the Kyoto Protocol to establish legally binding obligations for developed countries to reduce their greenhouse gas emissions.

Since it is in the gas phase, the amount of vapor present is quantified by the partial pressure of the gas.

Since the force imparted by a magnetic field is proportional to the charge on the particle, and the acceleration is proportional to the force divided by the mass of the particle, the magnets required to contain uranium gas would be impractically large ; most such designs have focussed on fuel cycles that do not depend upon retaining the fuel in the reactor.

Since the dielectric strength of gases varies depending on the shape and configuration of the electrodes, it is usually measured as a fraction of the dielectric strength of Nitrogen gas.

Since then, the U. S. has contributed to other large infrastructure programs including the Interstate Highway System, 1956-1990, with a dedicated financing system through the gas tax and a matching contribution between federal government and states at 90 % to 10 %.

Since thrust depends on both the amount of gas moved and the velocity, we can generate high thrust by accelerating a large mass of gas by a small amount, or by accelerating a small mass of gas by a large amount.

Since oil and gas pipelines are an important asset of the economic development of almost any country, it has been required either by government regulations or internal policies to ensure the safety of the assets, and the population and environment where these pipelines run.

Since quartz is very strong, the gas pressure can be higher, which reduces the rate of evaporation of the filament, permitting it to run a higher temperature ( and so luminous efficacy ) for the same average life.

Since methane clathrates are stable at a higher temperature than liquefied natural gas ( LNG ) (− 20 vs − 162 ° C ), there is some interest in converting natural gas into clathrates rather than liquifying it when transporting it by seagoing vessels.

Since then, large natural gas reserves have also been discovered.