This paper investigates the association between potential serum biomarkers and diabetes status in older Australians by employing traditional and machine learning methods. Data from Sydney Memory and Ageing Study (MAS) were interrogated cross-sectionally in 801 participants aged 70–90 years (n = 801). Twenty-eight serum biomarkers and 6 other factors were investigated as potential indicators that may distinguish diabetes status. Diabetes status was categorised as No-Diabetes, Pre-diabetes, and Type 2 diabetes (T2D). Diabetes is defined as follows when using fasting plasma glucose: no diabetes/ normal: < 5.6 mmol/L; prediabetes: 5.6–6.9 mmol/L; and diabetes: ≥ 7 mmol/L(1). Variable selection was executed using two distinct regression methods (i) multinomial logistic regression with backward selection and (ii) machine learning using elasticNet regression. Multiple imputation was used to address missing data. Age and sex were included as a priori covariates in the multinomial regression model. Using a multinomial logistic regression, Malondialdehyde (MDA), Macrophage inhibiting cytokine 1 (MIC1), and vitamin E were associated with diabetes status. MDA was strongly associated with diabetes with relative risk ratio (RRR) of 4.78 (95% CI = 3.39, 6.75; p < 0.001) when comparing to no diabetes, surpassing usual markers insulin, triglycerides, and waist-to-hip (WHR). Diabetes was associated with lower vitamin E levels, compared to no diabetes, with an RRR of 0.54 (95% CI:0.38, 0.75; p < 0.001). Comparing diabetes to prediabetes, RRR for lower vitamin E levels was 0.71 (95% CI: 0.51, 0.98; p = 0.035). MIC1 distinguished between diabetes and prediabetes status (RRR: 1.84; 95% CI:1.41, 2.41; p < 0.001). Consistent with the traditional methods, machine learning also identified MDA as being associated with T2D, with an odds ratio (OR) of 1.9, followed hierarchically by insulin (OR = 1.23), WHR (OR = 1.22) and triglyceride (OR = 1.13). Higher serum Vitamin E were associated with a lower risk of being in diabetes category (OR = 0.84). MIC1, urate, IL1b, HDL, and carotene were identified by the machine learning model, but showed minimal association. These results suggest that the oxidative stress and inflammation markers distinguish the state of having T2D.

We generalize the method of A. R. Booker (Poles of Artin L-functions and the strong Artin conjecture, Ann. of Math. (2) 158 (2003), 1089–1098; MR 2031863(2004k:11082)) to prove a version of the converse theorem of Jacquet and Langlands with relaxed conditions on the twists by ramified idèle class characters.

Chickpea is the third most important pulse crop worldwide. Changes in cropping system that necessitate late planting, scope for expansion in rice fallows and the global warming are pushing chickpeas to relatively warmer growing environment. Such changes demand identification of varieties resilient to warmer temperature. Therefore, the reference collection of chickpea germplasm, defined based on molecular characterization of global composite collection, was screened for high temperature tolerance at two locations in India (Patancheru and Kanpur) by delayed sowing and synchronizing the reproductive phase of the crop with the occurrence of higher temperatures ( ≥ 35°C). A heat tolerance index (HTI) was calculated using a multiple regression approach where grain yield under heat stress is considered as a function of yield potential and time to 50% flowering. There were large and significant variations for HTI, phenology, yield and yield components at both the locations. There were highly significant genotypic effects and equally significant G × E interactions for all the traits studied. A cluster analysis of the HTI of the two locations yielded five cluster groups as stable tolerant (n = 18), tolerant only at Patancheru (n = 34), tolerant only at Kanpur (n = 23), moderately tolerant (n = 120) and stable sensitive (n = 82). The pod number per plant and the harvest index explained ≥ 60% of the variation in seed yield and ≥ 49% of HTI at Kanpur and ≥ 80% of the seed yield and ≥ 35% of HTI at Patancheru, indicating that partitioning as a consequence of poor pod set is the most affected trait under heat stress. A large number of heat-tolerant genotypes also happened to be drought tolerant.

The impact of nano-structured surfaces on particle generation from ultrashort intense laser produced plasmas is presented over an intensity range of 1015–1017 Wcm−2. The nano-structured surface evidently produces hotter plasma but does not lead to the generation of hotter ions, a counterintuitive result based on present understanding of plasma expansion mechanism. Although the total ion flux and energy is more in the case of structured surfaces, the average energy of the projectiles is found to be lower than that from polished surfaces. The nano-structured surface shows preferential enhancement of lower energy ions and an intensity dependent divergence of the ejected particles.

The ability to design drugs (so-called ‘rational drug design’) has been one of the long-term objectives of chemistry for 50 years. It is an exceptionally difficult problem, and many of its parts lie outside the expertise of chemistry. The much more limited problem – how to design tight-binding ligands (rational ligand design) – would seem to be one that chemistry could solve, but has also proved remarkably recalcitrant. The question is ‘Why is it so difficult?’ and the answer is ‘We still don't entirely know’. This perspective discusses some of the technical issues – potential functions, protein plasticity, enthalpy/entropy compensation, and others – that contribute, and suggests areas where fundamental understanding of protein–ligand interactions falls short of what is needed. It surveys recent technological developments (in particular, isothermal titration calorimetry) that will, hopefully, make now the time for serious progress in this area. It concludes with the calorimetric examination of the association of a series of systematically varied ligands with a model protein. The counterintuitive thermodynamic results observed serve to illustrate that, even in relatively simple systems, understanding protein–ligand association is challenging.

Computational materials science has evolved in recent years into a reliable theory capable of predicting not only idealized materials and device performance properties, but also those that apply to practical engineering developments. The codes run on workstations and even now are fast enough to be useful design tools. A review will be presented of the current status of this rapidly advancing field. Examples of the accuracy of the codes are displayed by comparing the predicted atomic volumes, and cohesive and excess energies of several materials with experiment. As a further demonstration of the methods, the band structures of AlN, GaN, and InN in wurtzite and zinc blende structures will be presented. There are anomalies in the conduction and valence bands of these materials. Some consequences on light emitting and power devices made from these materials will be examined.

Computational materials science has evolved in recent years into a reliable theory capable of predicting not only idealized materials and device performance properties, but also those that apply to practical engineering developments. The codes run on workstations and even now are fast enough to be useful design tools. A review will be presented of the current status of this rapidly advancing field. Examples of the accuracy of the codes are displayed by comparing the predicted atomic volumes, and cohesive and excess energies of several materials with experiment. As a further demonstration of the methods, the band structures of AIN, GaN, and InN in wurtzite and zinc blende structures will be presented. There are anomalies in the conduction and valence bands of these materials. Some consequences on light emitting and power devices made from these materials will be examined.

SiGe alloys (< 1.5 % mismatch) were grown on Si (110) substrates at 700°C by molecular beam epitaxy. The structure and surface morphology were studied as a function of SiGe coverage (1.5mn–9nm) using atomic force microscopy, transmission electron microscopy and RHEED. A very high density of nanoscale SiGe ledges (less than 1 nm high and 1 μm long) were observed to form on the step terraces created during buffer layer growth. An interesting phenomenon is that the step bunches generated by the buffer growth and SiGe ledges are aligned along the elastically hardest <111> direction on the Si (110) surface. With increasing alloy thickness, the nanoscale SiGe ledges become longer and straighter. The effects of the surface instability and elastic anisotropy on the elastic relaxation effects are discussed.

We report on the epitaxial growth of Ge-C and Ge-Si-C alloys (C<10%) grown on Si(100) and Ge(100) substrates using low temperature (∼200°C) molecular beam epitaxy. Thin films (50–70 nm) were characterized in-situ by RHEED and ex-situ by transmission electron microscopy, xray diffraction, and Raman spectroscopy. The films were annealed at 750°C and 850°C in an Ar atmosphere to study interdiffusion effects.

Raman spectroscopy of Ge-C on Ge indicates the existence of a Ge-C local mode at 530cm−1 and is direct evidence for the presence of substitutional C in Ge. The GeSiC alloys grown on Ge do not show the Ge-C local mode, consistent with preferential Si-C bonding. There is evidence for strain enhanced solubility of C based on a comparison of the substitutional C content in Ge-C films on Si (∼1 at %) and on Ge substrates (∼0.1 at %). Silicon interdiffusion in annealed Ge-C samples is strongly suppressed by the presence of C. A simple diffusion model is used to illustrate Si indiffusion in Ge.

A novel low molar mass glassy chiral nematic oligomer has been developed that exhibits a large selective reflection bandwidth (>100 nm). This has immense potential in applications requiring the polarization of light over a broad spectral bandwidth, corresponding to the range of human vision, with minimal absorption and high efficiency. Definite advantages are observed over other low molar mass and polymeric chiral nematic materials reported in the literature that typically have narrower polarization bandwidths requiring more complex structures to cover the visible spectrum. The glass transition and clearing temperatures of this material are well separated, that in turn facilitates device processing. Devices up to 4"×5" have been successfully fabricated. Their optical properties are discussed.

Molecular beam epitaxial growth of Ge on Si(110) surfaces reveals interesting aspects of the heterogeneous nucleation of coherent Ge islands. Cleaning of the Si substrate by desorption of a passivating oxide layer at high temperature creates surface pits. Two sets of experiments, including deposition of Ge on as-cleaned substrates, and surfaces with a thin Si buffer layer are compared to illustrate the nucleation behavior of Ge. Typical Ge deposition temperatures range from 600°C to 725°C.

For Ge deposition on as-cleaned surfaces, the faceted edges of pits serve as preferential sites for the heterogeneous nucleation of coherent Ge islands. Experiments were also performed on surfaces with thin (˜20nm) Si buffer layers grown on the as-cleaned surface. Though the faceted pits have not been completely covered by the Si buffer layer, they have decreased in lateral size. In addition, the Si(110) surface shows ledges that are formed along specific crystallographic directions. Ge deposited on the Si buffer nucleates first at the corners of the pits, in an interesting dipole orientation, as well as along the ledges on the surface.

We report on the differences in the epitaxial growth mechanisms between Ge1−xCx (O<x<0.1) and Ge1−x−ySixCy (x=0.2, 0<y<0.05) alloys grown on Si(100) using low temperature( 200°C) molecular beam epitaxy. Thin films (50˜65nm) were characterized in situ by RHEED and ex situ by transmission electron microscopy and x-ray diffraction. With increasing C concentration, the microstructure of both Ge and GeSi alloys changes from 2D layer growth to 3D islanding. The d400 spacing of the relaxed alloys decreases marginally, with a maximum of 1at.% C being substitutionally incorporated. Ge-C films with higher C content have a high density of planar defects, typically twins and stacking faults. The addition of 20% Si does not appear to increase the amount of substitutional C in the films. Rather, the additions of 20% Si to Ge-C alloys somehow seems to enhance the tendency for the formation of planar defects.

Molecular beam epitaxial growth on GaAs(110) vicinal surfaces results in the formation of periodic micro-facets. We compare experimental results with computer simulations of a simple one dimensional step-flow growth model. The simulations show that preferential adatom attachment to the down step in a step array results in the destruction of step uniformity. A kinetic limitation due to adatom diffusion length along the terraces leads to stabilization of a periodic array of step-bunches. We extend our simulations to show the effects of the attachment and diffusion parameters on the dynamics of facet evolution.

Step bunching during epitaxial growth results in the transformation of a vicinal surface into a periodic array of micro-facets. Molecular beam epitaxial growth on the vicinal GaAs (110) surface exhibits this phenomenon which has primarily been characterized by electron microscopy. GaAs quantum wells with AlAs barriers were grown on GaAs(110) substrates vicinal 0.5-2· towards [010]. The faceting on the vicinal surface creates two distinct quantum well thicknesses. While most of the quantum well is 96Å thick, it broadens at the faceted regions. This thickness modulation produces two distinct luminescence peaks. By using temperature dependent photoluminescence, we have observed trends in exciton mobility. The exciton mobility decreases at low temperatures for the 1.0° and 2.0° samples, indicating a scattering mechanism. We will discuss interface roughness and other sources of scattering.

We report on the formation of lateral superlattices in short period vertical GaAs/AlAs superlattices. To explain the observed self-organized phase separation, we propose a model of vertical intermixing, driven by the exchange of Ga on the surface with impinging Al atoms. The model correctly describes the formation of lateral superlattices for both integer and fractional monolayer deposition. It also predicts a far-reaching intermixing at GaAs-AlAs interfaces. Insitu RHEED studies of the initial growth stage of both GaAs-AlAs and AlAs-GaAs interfaces support the assumption of an asymmetric exchange at the growing surface and confirm the longrange Ga migration predicted by the model.

The cuprate superconductor problem is approached from the conventional metallic standpoint, valid at dopings near the Tc maximum and beyond. There is strong evidence that the Tc maximum corresponds to EF lying at a van Hove singularity, a special situation leading to Marginal Fermi Liquid behavior, and also to a minimum in the isotope shift, as observed. The superconducting properties are discussed in the light of phononic and electronic pairing models.