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Texture-engineered ceramics enable access to a vast array of novel texture-property relations leading to property values ranging between those of single crystals and isotropic bulk ceramics. Recently developed templated grain growth and magnetic alignment texturing methods yield high quality crystallographic texture, and thus significant advances in achievable texture-engineered properties in magnetic, piezoelectric, electronic, optical, thermoelectric, and structural ceramics. In this paper, we outline the fundamental basis for these texture-engineered properties and review recent contributions to the field of texture-engineered ceramics with an update on the properties of textured lead-free and lead-based piezoelectrics. We propose that further property improvements can be realized through development of processes that improve crystallographic alignment of the grain structure, create biaxial texture, and explore a wider array of crystallographic orientations. There is a critical need to model the physics of texture-engineered ceramics, and more comprehensively characterize texture, thus enabling testing of texture orientation-property relations and materials performance. We believe that in situ measurements of texture evolution can lead to a more fundamental and comprehensive understanding of the mechanisms of texture development.

The purpose of this study was to address two methodological issues that have called into question whether previously reported gene–environment interaction (GxE) effects for adolescent alcohol use are ‘real’. These issues are (1) the potential correlation between the environmental moderator and the outcome across twins and (2) non-linear transformations of the behavioral outcome. Three environments that have been previously studied (peer deviance, parental knowledge, and potentially stressful life events) were examined here. For each moderator (peer deviance, parental knowledge, and potentially stressful life events), a series of models was fit to both a raw and transformed measure of monthly adolescent alcohol use in a sample that included 825 dizygotic (DZ) and 803 monozygotic (MZ) twin pairs. The results showed that the moderating effect of peer deviance was robust to transformation, and that although the significance of moderating effects of parental knowledge and potentially stressful life events were dependent on the scale of the adolescent alcohol use outcome, the overall results were consistent across transformation. In addition, the findings did not vary across statistical models. The consistency of the peer deviance results and the shift of the parental knowledge and potentially stressful life events results between trending and significant, shed some light on why previous findings for certain moderators have been inconsistent and emphasize the importance of considering both methodological issues and previous findings when conducting and interpreting GxE analyses.

A novel combination of low-field magnetic alignment (MA) and templated grain growth (TGG) was used to fabricate highly textured diamagnetic 0.72Pb(Mg1/3Nb2/3)O3–0.28PbTiO3 (0.72PMN–0.28PT) ceramics. Samples were produced by nonaqueous slip casting of PMN–PT slurries, in which diamagnetic plate-like 0.4(Na1/2Bi1/2)TiO3–0.6PbTiO3 (0.4NBT–0.6PT) template particles were aligned by dynamic MA in a 2.2-T permanent magnet array. Template alignment improved as slurry viscosity increased, with a 32-vol% solid loading (a viscosity of ∼0.1 Pa s at 0.1 s−1) giving optimal texture quality (7.85° FWHM, f = 92 vol%) after sintering and TGG. Alignment was stable for more than 3 h during slip casting, allowing fabrication of ∼1-cm thick textured ceramics with high piezoelectric response (d33 = 1222 pC/N). The success of dynamic MA at low magnetic field (2.2 T) is attributed to an increase in driving force for alignment of large (5–10 μm) template particles relative to the randomizing effect of Brownian motion (i.e., thermal energy kBT).

The feasibility of the SPER junction process as a reasonable alternative to the spike anneal junction is proved in this work. Good control of the SCE and performance competitive results as compared to the spike junction are obtained. An analysis of the interaction between the halo dopant and the SPER junctions has been carried out; it is shown that the performance degrades with increasing halo dose as a consequence of an overlap resistance problem.

The MgxZn1-xO alloy in wurtzite structure can be grown with Mg contents x up to 0.4. The band gap of the alloy increases with x. Furthermore, ZnO/MgxZn1-xO quantum well structures are of type I and thus are of interest for the active region of opto-electronic devices.

We report on in-plane photocurrent measurements of MgxZn1-xO epitaxial layers with x up to about 0.4 in the temperature range from 80 K to 300 K. Epitaxial films are either grown by plasma-assisted molecular beam epitaxy on c-plane sapphire substrates with a thin MgZnO buffer layer and by chemical vapor deposition on a-plane ZnO substrates. We map the evolution of the band gap transitions as a function of the Mg composition at different temperatures for the c-plane samples and as a function of polarization of the incoming light for an a-plane sample. The contributions of A, B and C interband transitions to the band gap signals are analysed and discussed.

The science of extra-solar planets is one of the most rapidly changing areas of astrophysics and since 1995 the number of planets known has increased by almost two orders of magnitude. A combination of ground-based surveys and dedicated space missions has resulted in 560-plus planets being detected, and over 1200 that await confirmation. NASA's Kepler mission has opened up the possibility of discovering Earth-like planets in the habitable zone around some of the 100,000 stars it is surveying during its 3 to 4-year lifetime. The new ESA's Gaia mission is expected to discover thousands of new planets around stars within 200 parsecs of the Sun. The key challenge now is moving on from discovery, important though that remains, to characterisation: what are these planets actually like, and why are they as they are?

In the past ten years, we have learned how to obtain the first spectra of exoplanets using transit transmission and emission spectroscopy. With the high stability of Spitzer, Hubble, and large ground-based telescopes the spectra of bright close-in massive planets can be obtained and species like water vapour, methane, carbon monoxide and dioxide have been detected. With transit science came the first tangible remote sensing of these planetary bodies and so one can start to extrapolate from what has been learnt from Solar System probes to what one might plan to learn about their faraway siblings. As we learn more about the atmospheres, surfaces and near-surfaces of these remote bodies, we will begin to build up a clearer picture of their construction, history and suitability for life.

The Exoplanet Characterisation Observatory, EChO, will be the first dedicated mission to investigate the physics and chemistry of Exoplanetary Atmospheres. By characterising spectroscopically more bodies in different environments we will take detailed planetology out of the Solar System and into the Galaxy as a whole.

EChO has now been selected by the European Space Agency to be assessed as one of four M3 mission candidates.

A consensus conference on the reasons for the undertreatment of depression was organized by the National Depressive and Manic Depressive Association (NDMDA) on January 17–18,1996. The target audience included health policymakers, clinicians, patients and their families, and the public at large. Six key questions were addressed: (1) Is depression undertreated in the community and in the clinic? (2) What is the economic cost to society of depression? (3) What have been the efforts in the past to redress undertreatment and how successful have they been? (4) What are the reasons for the gap between our knowledge of the diagnosis and treatment of depression and actual treatment received in this country? (5) What can we do to narrow this gap? (6) What can we do immediately to narrow this gap?

Atomic force microscopy (AFM) was invented in 1986 by Binnig, Quate, and Gerber as “a new type of microscope capable of investigating surfaces of insulators on an atomic scale.” Stemming from developments in scanning tunneling microscopy (STM), it became possible to image insulators, organic and biological molecules, salts, glasses, and metal oxides — some under a variety of conditions, e.g., ambient pressure, in aqueous or cryogenic liquids, etc. In 1987, Mate and co-workers introduced a new application for AFM where atomic-scale frictional forces could be measured. Likewise, in 1989, Burnham and Colton used the AFM to measure the surface forces and nano-mechanical properties of materials. Today, there are many examples of using AFM as a high-resolution profilometer, surface force probe, and nanoindentor. Several new imaging techniques have been introduced; each depending on the type of force measured, e.g., magnetic, electrostatic, and capacitative. Because of the diverse nature of the field and instrumentation, the names “scanned probe microscopy” and “XFM” (where X stands for the force being measured, e.g., MFM is magnetic force microscopy) have been adopted.