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Investigations are reported in a number of key applications areas for nanosecond pulsed Diode-Pumped Solid-State Lasers. Lasers with a range of pulse durations, frequencies, and pulse energies are assessed for performance in such applications as fine hole drilling in steels, cooling vane drilling, and machining three dimensional shapes in metals and composites. The effects of varying laser parameters are reported with respect to the interrelated phenomena of plasma formation, dimensional accuracy, material removal, dross formation and processed material properties. Process enhancements are also considered.It is found that lasers operating in this regime offer significant advantages in terms of process rates and achievable quality over competing industrial technologies.Investigations are reported in a number of key applications areas for nanosecond pulsed Diode-Pumped Solid-State Lasers. Lasers with a range of pulse durations, frequencies, and pulse energies are assessed for performance in such applications as fine hole drilling in steels, cooling vane drilling, and machining three dimensional shapes in metals and composites. The effects of varying laser parameters are reported with respect to the interrelated phenomena of plasma formation, dimensional accuracy, material removal, dross formation and processed material properties. Process enhancements are also considered.It is found that lasers operating in this regime offer significant advantages in terms of process rates and achievable quality over competing industrial technologies.

Electrical to EUV conversion efficiency is a key parameter for systems scaled to EUV emission in the 100W regime. Improvement in efficiency of conversion from laser radiation at the EUV source, reduces the required laser power and as such can lend itself to reduced heat load and debris emission. Also, improvement in the electrical to laser conversion efficiency results in a direct reduction in cost of ownership. Laser solutions optimised for efficient conversion to high M 2 CW laser radiation are not optimised in design for efficient short-pulsed operation; the mode of operation required for EUV generation. Aspects of both EUV source and laser design are discussed, with a view to optimising conversion efficiency for scalable EUV solutions.

Homophobia : An Australian History. Edited by Shirleene Robinson. Sydney: Federation Press, 2008. Pp. 262 A$39.95 paper. Homophobia, as Michael Flood and Clive Hamilton note in this important antho...

Publisher Summary This chapter provides an overview of the genetic basis of toxin production in Clostridium botulinum and Clostridium tetani. Classified as either tetanus neurotoxin (TeNT) or botulinum neurotoxin (BoNT), they are synthesized as single polypeptide chains that are subsequently cleaved by bacterial proteases to produce di-chain toxins, each comprising a light chain and a heavy chain linked by a single disulphide bridge. The molecular analysis of the toxin structural genes has played a significant part. Genetic analysis has also revealed other information on toxin production, gene transfer, diagnosis, and prevention. Representative genes of all of the clostridial neurotoxins, from the various serotypes and physiological groups, have been isolated and sequenced. Several groups have been involved in the development of oligonucleotide primers for the detection of neurotoxin genes using polymerase chain reaction based methods. Dissemination of the neurotoxin genes between the physiological groups implies that the genes are, or have been at one time, encoded on mobile genetic elements such as transposons, plasmids and bacteriophage genomes.

The IUPAC Conference on Physical Organic Chemistry (ICPOC) series of biennial conferences has a long history as the leading international meeting on physical organic chemistry. From its first installment in Crans sur Sierre (Switzerland) in 1972, ICPOC has acted as a focus point for the physical organic community worldwide, and the conference series enjoys a respected international reputation. With its focus on relating chemical behavior and properties to molecular structure through the development of (ideally quantitative) understanding of structure–property relationships, physical organic chemistry (POC) finds wide application in tackling current scientific challenges and has been undergoing something of a resurgence in recent years. ICPOC-21, held on 9-13 September 2012 at the University of Durham, UK, provided a forum for researchers (329 delegates from 38 countries) in academia and industry, and at all career stages, to present their results to the POC community and to exchange ideas, meet old friends, and make new contacts while enjoying spectacular views of the World Heritage castle and cathedral. In line with a developing interpretation of POC as a widely applicable approach to chemistry, the scientific program embraced three broad themes (physical underpinnings, mechanism and catalysis, and supramolecular chemistry) but often these strands were as inseparably interconnected as the three leaves held in unity in the minimal saddle trefoil adopted as the conference logo. The scope of the meeting is illustrated by the selection of contributions included in this issue of Pure and Applied Chemistry. In addition to the 24 plenary and keynote lectures, there were 120 contributed talks and 141 poster presentations. Donna Blackmond's paper on the interplay of thermodynamics and kinetics in dictating organocatalytic reactivity and selectivity demonstrates the use of kinetic modeling to provide mechanistic understanding leading to practical application. Martin Tanner's discussion of rearrangements catalyzed by indole alkaloid prenyltransferases shows how the experimental POC approach may shed light on enzyme mechanisms, while Dean Tantillo describes the application of quantum chemical dynamics calculations to mechanistic problems in the field of terpene biosynthesis, and a blend of experiment and computation is presented in Brian Ohta's account of the structure of halonium ions in superacidic solutions. Hiromitsu Maeda reviews research on various stimuli-responsive circularly polarized luminescence properties derived from π-conjugated molecules and related materials, and Jason Harper summarizes progress towards a predictive understanding of how ionic solvents affect and control organic reactivity. Finally, Izumi Iwakura reports directly observations of the Claisen rearrangement by timeresolved vibrational spectroscopy using a few-optical-cycle pulse laser. This selection of excellent work provides only a taste, but the conference as a whole showed that the international POC community is as vital and vibrant as it has ever been, promising exciting times ahead for this approach to chemistry. The next ICPOC will be held in Ottawa (Canada) 10-15 August 2014 under the chairmanship of Prof. Paul Mayer (University of Ottawa). Further information can be found at http://events.science.uottawa. ca/icpoc22/welcome.html.Ian H. Williams Conference Chair and Editor

High-brightness extreme-ultraviolet light sources are required for mask inspections and metrology, including mask blank inspection, actinic pattern inspection, and aerial image measurement system to improve yield and lower cost of ownership. Laser-produced plasma (LPP) light sources have the highest potential to achieve the brightness requirements for all the range of mask inspection tools currently foreseen. High brightness of LPP sources (100 to 1000 W/mm2 sr) is the result of a smaller source size ( ∼ 0.1 mm) than that of competing technologies. Since brightness is inversely proportional to the area of the source, smaller source size corresponds with greater brightness and hence greater inspection throughput. At the Laboratory for Energy Conversion of ETH Zurich, a fully operational continuous-running multi-kHz LPP light source has been developed over the last five years and is now undergoing system optimization. Adlyte, a spin-off of ETH Zurich, is working with industry leaders to commercialize this LPP source. Individual subsystem configuration and the physical boundary conditions and limitations that affect power, brightness, stability, and lifetime management are discussed. This integrated system produces a measured brightness of 259 W/mm2 sr. Outlook for the future growth and integration of the source in high-volume manufacturing tools is then discussed.

Biocatalytic resolutions of methyl sulfinylacetates fford sulfoxides (R)-( 1 ) - ( 6 ) in very high optical yields; the products have been used in a systematic study of the “SPAC” reaction, an asymmetric synthesis of γ-hydroxy-α,β-unsaturated esters.

A general and efficient solid-phase synthesis of N-9-substituted 2,8-diaminopurines from 5-nitrouracil is described. The key synthetic transformation employs a carbodiimide-mediated cyclization of a thiourea. Thiourea formation on solid phase is performed using both thermal and microwave reaction conditions. Regiospecific solution-phase synthesis of key building blocks allows the incorporation of desired substituents at N-9 of the purine nucleus.

Biocatalytic resolutions of methyl sulfinylacetates fford sulfoxides (R)-( 1 ) - ( 6 ) in very high optical yields; the products have been used in a systematic study of the “SPAC” reaction, an asymmetric synthesis of γ-hydroxy-α,β-unsaturated esters.

THIS ONE-DAY CONFERENCE on 18 April 1986 at the University of Birmingham, jointly sponsored by the Royal African Society and the Department of Extra-Mural Studies, Birmingham, brought together 57 participants drawn from public life, business, the academic world, journalism and the diplomatic service to discuss current problems and future prospects for relations between South Africa and her neighbours in the Southern African Development Co-ordination Conference. The special focus was on the possible impact of sanctions on the states. The conference was opened by Douglas Rimmer, Vice-Chairman of the Council of the Royal African Society. He thanked Ian and Willie Henderson for their initiative in calling the conference, and urged that the meetings should be used not to provide an outlet for the passions which South African affairs provoke, but to examine objectively the oppositions of ideologies, economic interests and political forces in the region. He called for reali-sm in a spirit of free enquiry and rational debate. The day was divided into four sessions, the first of which provided a historical perspective to the formation of SADCC in 1980. Ian Henderson's paper reviewed South Africa's relations with the region from 1910 to 1975, reminding participants that Smuts's objectives in seeking afronding (rounding-off) of the Union's frontiers in the years after 1910 by the incorporation of the High Commission Territories were similar to the goals of detente in the 1970s: to structure the politics and the economies of southern Africa so that the Union/Republic defined development ob jectives for her neighbours in the interests of white South Africa. In one sense, South Africa's regional diplomacy in the 20th century was highly unsuccessful, Namibia being the only addition to the frontiers of 1910. But in a more important sense, South Africa's 'informal empire' in the region expanded in a silent but effective process about which little has been written. Responding to the theme that South Africa had failed by diplomacy to achieve direct political control over the hinterland, Willie Henderson looked at the origins of SADCC, not so much as a set of written agreements produced by the front-line states at the height of the war in Rhodesia but as a search for effective regional diplomatic alliances pre-dating the front-line brotherhood. Seretse Khama's key role in picking up and developing the

Double diastereoselection in the S ulfoxide P iperidine A nd C arbonyl ( SPAC ) reactions of sulfinyl acetate esters (2) with α-unsubstituted aldehydes (3) has been investigated to facilitate asymmetric syntheses of γ-hydroxy-α,β-unsaturated esters (1) .