The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.

Single-particle reconstruction can be used to perform three-dimensional (3D) imaging of homogeneous populations of nano-sized objects, in particular viruses and proteins. Here, it is demonstrated that it can also be used to obtain 3D reconstructions of heterogeneous populations of inorganic nanoparticles. An automated acquisition scheme in a scanning transmission electron microscope is used to collect images of thousands of nanoparticles. Particle images are subsequently semi-automatically clustered in terms of their properties and separate 3D reconstructions are performed from selected particle image clusters. The result is a 3D dataset that is representative of the full population. The study demonstrates a methodology that allows 3D imaging and analysis of inorganic nanoparticles in a fully automated manner that is truly representative of large particle populations.

A new method to perform X-ray absorption correction for spherical particles in quantitative energy-dispersive X-ray spectroscopy in the scanning transmission electron microscope is presented. An absorption correction factor is derived and simulated data is presented encompassing a range of X-ray absorption conditions. Theoretical calculations are compared with experimental data of X-ray counts from Au nanoparticles to verify the derived methodology. The effect of detector elevation angle is considered and a comparison with thin-film absorption correction is included.

Comparative politics has witnessed periodic debates between proponents of contextually sensitive area studies research and others who view such work as unscientific, noncumulative, or of limited relevance for advancing broader social science knowledge. In Southeast Asia in Political Science: Theory, Region, and Qualitative Analysis, edited by Erik Martinez Kuhonta, Dan Slater, and Tuong Vu, a group of bright, young Southeast Asianists argue that contextually sensitive research in Southeast Asia using qualitative research methods has made fundamental and lasting contributions to comparative politics. They challenge other Southeast Asianists to assert proudly the contributions that their work has made and urge the rest of the comparative politics discipline to take these contributions seriously. This symposium includes four short critical reviews of Southeast Asia in Political Science by political scientists representing diverse scholarly traditions. The reviews address both the methodological and the theoretical orientations of the book and are followed by a response from the editors.

The new generation of energy-dispersive X-ray (EDX) detectors with higher count rates than ever before, paves the way for a new approach to quantitative elemental analysis in the scanning transmission electron microscope. Here we demonstrate a method of calculating partial cross sections for use in quantifying EDX data, beneficial especially because of the simplicity of its implementation. Applying this approach to acid-leached PtCo catalyst nanoparticles leads to quantitative determination of the Pt surface enrichment.

Revisionists have argued that no empire-wide persecution of Christians occurred in the late first century and that Domitian was neither a persecutor of Christians nor an evil, incompetent ruler. This essay agrees with those points but also argues that a closer examination of extant Roman and Christian late first/early second century writers demonstrates that Christians were held in low esteem and suffered in Roman society because of their religious convictions. This study argues that Revelation was a Christian response to religio-political pressures by indigenous Asian pagans upon Christians to conform to traditional social practices in Roman Asia.

John J. Collins' recent study of the interpretation of Dan 7.13 in the extant Jewish literature in the first century CE has provided a needed survey and background for those interested in the interpretation of Dan 7.13 in Christian circles during the same period. Collins identifies four common features between the Similitudes of Enoch and 4 Ezra 13. First, both books assume that the humanlike figure refers to an individual and is not a collective symbol. Secondly, both identify this figure as the messiah. Thirdly, in both the messiah is preexistent and both associate with the messiah prerogatives traditionally reserved for God in Jewish literature. Finally, the messiah takes a more active role in the defeat of the ungodly in the Similitudes of Enoch and 4 Ezra than in Dan 7.13. He argues that these common features between two works which do not exhibit any direct literary or theological dependence indicate certain common assumptions in the first century CE concerning Dan 7.13, but he also states that it is difficult to ascertain how widespread these assumptions might have been.

Comparative political analysts seek empirical generalizations which will hold water across systems and over a period of time. Yet, modeling important political phenomena over more than a handful of countries is still rather unusual. One focus for substantial comparative research has been the coup d'état—an irregular change of governmental leadership by force—in African countries. Scholars who have engaged in this research find they have various conceptual and methodological differences of opinion. In this Controversy, Robert Jackman and Rosemary O'Kane raise the issues in dispute. Their contentions are answered by Thomas Johnson, Pat McGowan, and Robert Slater. The exchange highlights important research issues without necessarily resolving them.

The purpose of this article is to contribute to the theoretical understanding of African military coups d'etat. We begin by replicating a well-known model (Jackman, 1978) that purports to identify the structural determinants of coups d'etat within the states of Sub-Saharan Black Africa. When the research problem is changed slightly to focus exclusively on military coups, we find major weaknesses in the original Jackman model. We then extend and refine this model and thereby account in a theoretically meaningful fashion for 91% of the variation in military coups within 35 Black African states from 1960 through 1982. Our major substantive findings indicate that Black African states with relatively dynamic economies whose societies were not very socially mobilized before independence and which have maintained or restored some degree of political participation and political pluralism have experienced fewer military coups, attempted coups, and coup plots than have states with the opposite set of characteristics.

Certain derivatives of benzacridine and of 4-anilinoquinoline give a blue or red colouration with a solution of iodine in aqueous potassium iodide. In the case of the active anilinoquinoline compounds the colour is usually developed in presence of solutions containing iodine at a concentration of the order of N/10,000, whilst in the case of the benzacridine compounds the colour is still apparent at concentrations of N/100,000 or even less. The effect of variation of concentration of compound, iodine, and hydrogen ions has been investigated in certain instances. The action of certain inorganic salts has also been investigated, but in low concentrations these are without much effect. The methosulphates of the two active benzacridine bases also develop colours with iodine even with very low concentrations of the latter. It is suggested that these methosulphates form micellar, colloidal solutions. The chromogenic property appears to depend not on the nitrogen atom in these compounds but on the structure of the molecule as a whole. The compounds which have been investigated differ from most of those previously known to give colours with iodine, in that they are basic and form colloidal solutions in which the particles are positively charged.