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In the 19th century , geometers developed a powerful " calculus " for solving enumerative problems . For example , while ethics might have little to contribute to understanding the mechanism of influenza virus transmission , it can make a significant contribution to debates such as what levels of harm the public are prepared to accept , how the burdens of negative outcomes should be distributed across the population and whether or not more resources should be invested in stockpiling antiviral medications . It is my sincere wish that the process will further progress and result in a significant contribution to the solution of global environmental problems . Included in the definition of a substantial obstacle are abortion regulations that would pose a significant threat to a woman ’ s health or life . The ‘ micro ’ international career path of the individual makes a significant contribution to the making of world city networks . Further , we know that policy in certain fields such as housing , play a significant role in shaping the sectarian geography of our cities and towns .