Stroke and plasma markers of milk fat intake – a prospective nested case-control study

<p>Abstract</p> <p>Background</p> <p>Dairy products are high in saturated fat and are traditionally a risk factor for vascular diseases. The fatty acids 15:0 and 17:0 of plasma lipids are biomarkers of milk fat intake. The aim of the present study was to evaluate the risk of a first-ever stroke in relation to the plasma milk fat biomarkers.</p> <p>Methods</p> <p>A prospective case-control study was nested within two population based health surveys in Northern Sweden. Among 129 stroke cases and 257 matched controls, plasma samples for fatty acid analyses were available in 108 cases and 216 control subjects. Proportions of 15:0 and 17:0 of plasma lipids, weight, height, blood lipids, blood pressures, and lifestyle data were employed in conditional logistic regression modelling.</p> <p>Results</p> <p>The proportions of fatty acids 17:0 and 15:0+17:0 of total plasma phospholipids were significantly higher in female controls than cases, but not in men. 17:0 and 15:0+17:0 were significantly and inversely related to stroke in the whole study sample as well as in women. The standardised odds ratio (95% CI) in women to have a stroke was 0.41 (0.24–0.69) for 17:0 in plasma phospholipids. Adjustment for traditional cardiovascular risk factors, physical activity and diet had marginal effects on the odds ratios. A similar, but non-significant, trend was seen in men.</p> <p>Conclusion</p> <p>It is hypothesised that dairy or milk fat intake may be inversely related to the risk of a first event of stroke. The intriguing results of this study should be interpreted with caution. Follow up studies with greater power, and where intakes are monitored both by dietary recordings and fatty acid markers are needed.</p

Wide-aperture GaAs/AlGaAs multiple quantum well electro-optic modulators

We present design and fabrication methods for surface normal monolithic amplitude modulators with an aperture up to 14 × 14 mm2, a contrast ratio of 6:1 and for low driving voltages (=8 V). The modulators consist of undoped GaAs/AlGaAs quantum wells embedded in a Fabry-Perot (FP) resonance cavity grown by MOVPE. To improve the device performance the FP cavity, the period and thickness of the quantum well and doping concentration were optimised. Also, the dimension of the modulator were varied from 0.5 × 0.5 to 14 × 14 mm2. The results show that the yield of the modulators increases significantly when decreasing the size of the modulators. To remedy the low yield issue for wide aperture modulator, a pixelated approach was used to divide the mono pixel in a monolithic modulator into several pixels, for example from 4 to 48. The modulation speed of the modulators with different dimensions was characterised by electro-optic (EO) response measurements. The temporal optical response of the large modulators was satisfactory up to the order of MHz modulation frequency where the RC constant limited the performance. A few of the modulators with wide apertures are to be assembled into an optical link system for free-space communication.</p

Silica Hybrid Sol-Gel Materials with Unusually High Concentration of Pt-Organic Molecular Guests: Studies of Luminescence and Nonlinear Absorption of Light

The development of new photonic materials is a key step toward improvement of existing optical devices and for the preparation of a new generation of systems. Therefore synthesis of photonic hybrid materials with a thorough understanding and control of the microstructure-to-properties relationships is crucial. In this perspective, a new preparation method based on fast gelation reactions using simple dispersion of dyes without strong covalent bonding between dye and matrix has been developed. This new sol-gel method is demonstrated through synthesis of monolithic siloxane-based hybrid materials highly doped by various platinum(II) acetylide derivatives. Concentrations of the chromophores as high as 400 mM were obtained and resulted in unprecedented optical power limiting (OPL) performance at 532 nm of the surface-polished solids. Static and time-resolved photoluminescence of the prepared hybrid materials were consistent with both OPL data and previous studies of similar Pt(II) compounds in solution. The impacts of the microstructure and the chemical composition of the matrix on the spectroscopic properties, are discussed