The current trends in stimulated Brillouin scattering and optical phase conjugation are overviewed. This report is formed by the selected papers presented in the “Fifth International Workshop on stimulated Brillouin scattering and phase conjugation 2010” in Japan. The nonlinear properties of phase conjugation based on stimulated Brillouin scattering and photo-refraction can compensate phase distortions in the high power laser systems, and they will also open up potentially novel laser technologies, e.g., phase stabilization, beam combination, pulse compression, ultrafast pulse shaping, and arbitrary waveform generation.

This issue of the Journal features collaborative follow-up studies of two unique pregnancy cohorts recruited during 1959–1966 in the United States. Here we introduce the Early Determinants of Adult Health (EDAH) study. EDAH was designed to compare health outcomes in midlife (age 40s) for same-sex siblings discordant on birthweight for gestational age. A sufficient sample of discordant siblings could only be obtained by combining these two cohorts in a single follow-up study. All of the subsequent six papers are either based upon the EDAH sample or are related to it in various ways. For example, three papers report results from studies that significantly extended the ‘core’ EDAH sample to address specific questions.

We first present the overall design of and rationale for the EDAH study. Then we offer a synopsis of past work with the two cohorts to provide a context for both EDAH and the related studies. Next, we describe the recruitment and assessment procedures for the core EDAH sample. This includes the process of sampling and recruitment of potential participants; a comparison of those who were assessed and not assessed based on archived data; the methods used in the adult follow-up assessment; and the characteristics at follow-up of those who were assessed. We provide online supplementary tables with much further detail. Finally, we note further work in progress on EDAH and related studies, and draw attention to the broader implications of this endeavor.

A differential inequality technique is used to determine a lower bound on the blow-up time for solutions to the heat equation subject to a nonlinear boundary condition when blow-up of the solution does occur. In addition, a sufficient condition which implies that blow-up does occur is determined.

A broad division of the opportunist mycobacteria has been defined under the name of ‘dysgonic nonchromogens’. The classification was attempted of 68 strains isolated from man in England and Wales, of which 54 at least appeared to be clinically significant. The means used were chiefly drug sensitivity, arylsulphatase activity, specific agglutination, lipid analysis and pathogenicity tests on fowls. On the results, a new definition is proposed for the species M. avium, extending beyond the boundaries of pathogenicity for birds, and a scheme put forward for its division into two types. In addition, two provisional new species and a group of ‘para-avian’ bacilli have been recognized and defined. The remaining 16 strains included six with ‘Battey’ serotypes but otherwise could not be classified. The need for standardization of fowl tests has been noted together with their diminished importance in the field of classification with the emergence of new in vitro methods of examination.

Typing of Mycobacterium avium strains obtained in a study of endemic tuberculosis in a Wildfowl Reserve permitted the recognition of two separate infected groups. The main infection was in Anatidae and was due to M. avium, type 1; the other was in chickens used for incubation and brooding and the predominance in it of type 2 agreed with normal experience of birds, pigs and cattle in Britain. Many of the strains isolated from the Anatidae were aberrant and methods used to investigate these are described; two of the strains may belong to a new type. Birds which died from other causes, usually trauma, often had subclinical tuberculosis and 5% of the samples of mud and soil examined yielded M. avium.

This study investigated the effect of environmental variables such as soil class, soil water availability, topography and slope on spatial distribution patterns of tree species in a Brazilian Seasonal Semideciduous Forest area. Floristic and structural data for a tree community were obtained by sampling 100 plots 10 × 10 m in which every tree with trunk diameter (dbh) ⩾ 4.77 cm at 130 cm above ground level was sampled. The area under study showed a marked soil gradient, directly associated with the topography: flat hilltops with Al3+-rich Dystric Latosols give way to steep colluvial slopes with shallower and more Dystric Cambic Latosols without Al3+, changing over, at the bottom of the hollows, to Epieutrophic Cambisols richer in nutrients. The floristic-sociological parameters analysed for the soil habitats did not differ statistically from each other. The diversity and equability indices were 3.6 and 0.84, 3.48 and 0.85, 3.49 and 0.84 for the Dystric Latosol, Dystric Cambic Latosol and Epieutrophic Cambisol, respectively. The soil variables (related to the fertility and texture) and the soil water regime (drainage) were probably the principal factors determining the spatial distribution patterns of tree species in the forest.

We study a class of initial-boundary-value problems for which an auxiliary condition of the formis prescribed. We determine bounds on an energy expression by means of differential inequalities and derive pointwise bounds for the solution and its gradient by use of a parabolic maximum principle.

The structure and properties of a series of modified polydimethylsiloxane (PDMS) elastomers reinforced by in situ generated silica particles were investigated. The PDMS elastomer was modified by systematically varying the molecular weight between reactive groups incorporated into the backbone. Tetraethoxysilane (TEOS) and partial hydrolyzate of TEOS were used to generate silica particles. The chemistry and phase structure of the materials were investigated by 29Si magic angle spinning nuclear magnetic resonance (NMR) spectroscopy and swelling experiments.

A combination of small angle scattering (SAS) and neutron spin-echo (NSE) spectroscopy is used to characterize the structure and dynamics of polymeric silica aerogels during sintering. The SAS data indicate that densification at short length scales precedes the densification at longer scales (comparable to that of the pore structure). Interpreted within the fracton model, the NSE data are consistent with an initial decrease in connectivity during relatively early stages of densification.

New approaches to both second-order and third-order nonlinear optical materials are presented. A series of organometallic and organic salts, in which the cation has been designed to have a large molecular hyperpolarizability, has been prepared and the SHG efficiencies were measured. Partially substituted derivatives of polyacetylene are synthesized via the ring-opening metathesis polymerization (ROMP) of cyclooctatetraene (COT) and its derivatives. Certain poly-COT derivatives afford soluble, highly conjugated polyacetylenes. These materials exhibit large third-order optical nonlinearities and low scattering losses.

Small-angle X-ray scattering is used to characterize the structure of aerogels prepared by two-stage polymerization processes. Second-stage catalysis controls the resistance to collapse during drying with the base-catalyzed system being most resistant. Base catalysis in the second stage leads to compaction of the polymer network on short length scales. This short-scale rigidity makes the networks sufficiently robust to withstand the surface tension forces present during solvent extraction and re-exposure to the atmosphere. Aging in solution also improves aerogel quality. In this case, a dissolution-repolymerization process leads to short length scale circuits and improved rigidity.