Capturing Government Policy on the Left-Right Scale: Evidence from the United Kingdom, 1956-2006

The left-right scheme is the most widely used and parsimonious representation of political competition. Yet, long time series of the left-right position of governments are sparse. Existing methods are of limited use in dynamic settings due to insufficient time points which hinders the proper specification of time-series regressions. This article analyses legislative speeches in order to construct an annual left-right policy variable for Britain from 1956 to 2006. Using a recently developed content analysis tool, known as Wordscores, it is shown that speeches yield valid and reliable estimates for the left-right position of British government policy. Long time series such as the one proposed in this article are vital to building dynamic macro-level models of politics. This measure is cross-validated with four independent sources: (1) it compares well to expert surveys; (2) a rightward trend is found in post-war British government policy; (3) Conservative governments are found to be more right wing in their policy outputs than Labour governments; (4) conventional accounts of British post-war politics support the pattern of government policy movement on the left-right scale

Encapsulation of xenon by bridged resorcinarene cages with high ¹²⁹Xe NMR chemical shift and efficient exchange dynamics

Abstract Functionalized cages encapsulating xenon atoms enable highly sensitive, background-free molecular imaging through a technique known as HyperCEST ¹²⁹Xe MRI. Here, we introduce a class of potential biosensor cage structures based on two resorcinarene macrocycles bridged either by aliphatic carbon chains or piperazines. First-principles-based modeling predicts a high chemical shift (about 345 ppm) outside the typical experimental observation window for ¹²⁹Xe encapsulated by the aliphatically bridged cage and two ¹²⁹Xe resonances for the piperazine-bridged cages corresponding to single and double loading. Based on the computational predictions as well as ¹²⁹Xe chemical exchange saturation transfer (CEST) and T₂ relaxation nuclear magnetic resonance experiments, we confirm Xe encapsulation in the aliphatically bridged and double encapsulation in the piperazine-bridged resorcinarene in methanol. The cages show fast Xe exchange rates (12,000–49,000 s⁻¹), resulting in a high CEST response regardless of the relatively low binding constant (0.09–3 M⁻¹)