It is challenging to produce reliable Cu wiring on the nanometer scale for scaled-down devices.
To use rather less euphemistic terminology, both al-Qadir and Feghoul were released because the administration was unable to build a case against them, and, as I indicated above, because the authorities are anxious to scale down the challenge to executive power that was manifested by the Supreme Court in June's ruling in Boumediene v. Bush.
Furthermore, pumped-storage hydroelectricity and compressed air energy storage are challenging to scale-down, while batteries are challenging to scale-up.
The central challenge of scaling down to the cellular level is capturing such a tiny amount of template and amplifying it to generate enough material for high-throughput sequencing.
Another challenge came last week from the military think-tank RUSI, which published a report suggesting that scaling down the UK's nuclear deterrent was a credible and legitimate option.
Of these, propulsion has been challenging to scale down, given the stringent physical constraints associated with space thrusters.
The myriad of bottom-up top-down challenges for scaling these types of interventions will be discussed, as well as opportunities for future research.
Despite having in 2011 scaled down a similar scheme run by Labour, the government will invest £5m this year, and more in coming years, to build a national network of grassroots organisations to challenge all forms of extremist ideology.
I also discuss the challenges connected to scaling down perception to nano and pico aerial vehicles, where sensing and computation are subject to strict payload and power constraints.
These bots have far fewer working parts, but scaling down has come with significant design challenges of its own.
The power of a battery depends on its volume, and scaling down the size while maintaining the power has proved to be a tremendous challenge.
