The insulin receptor is a phylogenetically ancient tyrosine kinase receptor found in organisms as primitive as cnidarians and insects. In higher organisms it is essential for glucose homeostasis, whereas the closely related insulin-like growth factor receptor (IGF-1R) is involved in normal growth and development. The insulin receptor is expressed in two isoforms, IR-A and IR-B; the former also functions as a high-affinity receptor for IGF-II and is implicated, along with IGF-1R, in malignant transformation. Here we present the crystal structure at 3.8 A resolution of the IR-A ectodomain dimer, complexed with four Fabs from the monoclonal antibodies 83-7 and 83-14 (ref. 4), grown in the presence of a fragment of an insulin mimetic peptide. The structure reveals the domain arrangement in the disulphide-linked ectodomain dimer, showing that the insulin receptor adopts a folded-over conformation that places the ligand-binding regions in juxtaposition. This arrangement is very different from previous models. It shows that the two L1 domains are on opposite sides of the dimer, too far apart to allow insulin to bind both L1 domains simultaneously as previously proposed. Instead, the structure implicates the carboxy-terminal surface of the first fibronectin type III domain as the second binding site involved in high-affinity binding.

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Theories of democratic government traditionally have relied on a model of organization in which officials act impartially, accept clear lines of accountability and supervision, and define their dayto-day activities through rules, procedures, and confined discretion. In the past 10 years, however, a serious challenge to this ideal has been mounted by critics and reformers who favor market, network, or "mixed-economy" models. We assess the extent to which these new models have influenced the work orientations of frontline staff using three alternative service types-corporate, market, and network-to that proposed by the traditional, procedural model of public bureaucracy. Using surveys of frontline officials in four countries where the revolution in ideas has been accompanied by a revolution in methods for organizing government services, we measure the degree to which the new models are operating as service-delivery norms. A new corporatemarket hybrid (called "enterprise governance") and a new network type have become significant models for the organization of frontline work in public programs.

Governments are increasingly turning to public sector innovation (PSI) labs to take new approaches to policy and service design. This turn towards PSI labs, which has accelerated in more recent years, has been linked to a number of trends. These include growing interest in evidence-based policymaking and the application of 'design thinking' to policymaking, although these trends sit uncomfortably together. According to their proponents, PSI labs are helping to create a new era of experimental government and rapid experimentation in policy design. But what do these PSI labs do? How do they differ from other public sector change agents and policy actors? What approaches do they bring to addressing contemporary policymaking? And how do they relate to other developments in policy design such as the growing interest in evidence-based policy and design experiments? The rise of PSI labs has thus far received little attention from policy scientists. Focusing on the problems associated with conceptualising PSI labs and clearly situating them in the policy process, this paper provides an analysis of some of the most prominent PSI labs. It examines whether labs can be classified into distinct types, their relationship to government and other policy actors and the principal methodological practices and commitments underpinning their approach to policymaking. Throughout, the paper considers how the rise of PSI labs may challenge positivist framings of policymaking as an empirically driven decision process.

In 1998, we were witnessing major changes in frontline social service delivery across the OECD and this was theorised as the emergence of a post-Fordist welfare state. Changes in public management thinking, known as New Public Management (NPM), informed this shift, as did public choice theory. A 1998 study of Australia's then partially privatised employment assistance sector provided an ideal place to test the impact of such changes upon actual service delivery. The study concluded that frontline staff behaviour did not meet all the expectations of a post-Fordist welfare state and NPM, although some signs of specialisation, flexibility and networking were certainly evident (Considine, 1999). Ten years on, in 2008, frontline staff working in Australia's now fully privatised employment sector participated in a repeat study. These survey data showed convergent behaviour on the part of the different types of employment agencies and evidence that flexibility had decreased. In fact, in the ten years between the two studies there was a marked increase in the level of routinisation and standardisation on the frontline. This suggests that the sector did not achieve the enhanced levels of flexibility so often identified as a desirable outcome of reform. Rather, agencies adopted more conservative practices over time in response to more detailed external regulation and more exacting internal business methods.