Higher Vitamin D2 and 25(OH)D2, but Not Vitamin D3 Metabolites, in Bovine Plasma and Muscle from Grass-Based Finishing System, Compared to Concentrate

Meat and meat products are one of the largest contributors to vitamin D dietary intakes. Little is known, however, about how different animal husbandry practices and/or finishing diets might affect the vitamin D content of the animal. Therefore, this study aimed to investigate the effect of bovine finishing diet (grass vs. concentrate) on the 25(OH)D plasma concentrations of cattle and subsequent vitamin D content in beef. Cattle were fed grass (n = 7) or concentrate (n = 9) finishing diets for 15 weeks prior to slaughter. Bovine blood samples were collected at slaughter and plasma aliquots were stored (−80 °C) until analysis. Beef top rump from each animal was chilled for an ageing period of 21 days, then homogenised and frozen (−80 °C) until analysis. Bovine plasma samples were analysed for circulating 25(OH)D3, and 25(OH)D2 (nmol/L), and raw beef muscle (top rump) samples were analysed for vitamin D metabolites; vitamin D3, vitamin D2, 25(OH)D3 and 25(OH)D2 (µg/kg), all by LC-MS/MS. Total vitamin D activity was defined: [vitamin D3 + (25(OH)D3 × 5) + vitamin D2 + (25(OH)D2 × 5)]. Statistical analysis was conducted by SPSS with independent t tests used to compare groups; significance level p < 0.05. Data were presented as mean ± SD. A significantly higher plasma 25(OH)D2 concentration was observed in the grass finished cattle compared to the concentrate group (43.18 ± 11.75 vs. 16.56 ± 1.58 nmol/L, p < 0.002). No difference in plasma 25(OH)D3 concentrations was observed between groups. In beef top rump, the grass finishing diet resulted in a significantly higher mean ± SD vitamin D2 [0.07 ± 0.05 vs. 0.01 ± 0.01 µg/kg] and 25(OH)D2 [0.70 ± 0.16 vs. 0.25 ± 0.07 µg/kg] compared to concentrate finishing diet (both p < 0.001). Moreover, beef from grass finished cattle demonstrated a significantly higher total vitamin D activity compared to those in the concentrate group [9.52 ± 2.43 vs. 6.78 ± 2.00 µg/kg, p < 0.05]. No difference was observed for muscle vitamin D3 or 25(OH)D3 between groups. In conclusion, a more favourable bovine vitamin D profile, driven by vitamin D2 metabolites specifically (not vitamin D3), is reported from a grass-based finished system, compared to concentrate finishing. Further research is required to understand the impact of these findings for both agriculture practices and human nutrition

Local-Oscillator Noise Coupling in Balanced Homodyne Readout for Advanced Gravitational Wave Detectors

The second generation of interferometric gravitational wave detectors are quickly approaching their design sensitivity. For the first time these detectors will become limited by quantum back-action noise. Several back-action evasion techniques have been proposed to further increase the detector sensitivity. Since most proposals rely on a flexible readout of the full amplitude- and phase-quadrature space of the output light field, balanced homodyne detection is generally expected to replace the currently used DC readout. Up to now, little investigation has been undertaken into how balanced homodyne detection can be successfully transferred from its ubiquitous application in table-top quantum optics experiments to large-scale interferometers with suspended optics. Here we derive implementation requirements with respect to local oscillator noise couplings and highlight potential issues with the example of the Glasgow Sagnac Speed Meter experiment, as well as for a future upgrade to the Advanced LIGO detectors.Comment: 7 pages, 5 figure

Effects of static and dynamic higher-order optical modes in balanced homodyne readout for future gravitational waves detectors

With the recent detection of Gravitational waves (GW), marking the start of the new field of GW astronomy, the push for building more sensitive laser-interferometric gravitational wave detectors (GWD) has never been stronger. Balanced homodyne detection (BHD) allows for a quantum noise (QN) limited readout of arbitrary light field quadratures, and has therefore been suggested as a vital building block for upgrades to Advanced LIGO and third generation observatories. In terms of the practical implementation of BHD, we develop a full framework for analyzing the static optical high order modes (HOMs) occurring in the BHD paths related to the misalignment or mode matching at the input and output ports of the laser interferometer. We find the effects of HOMs on the quantum noise limited sensitivity is independent of the actual interferometer configuration, e.g. Michelson and Sagnac interferometers are effected in the same way. We show that misalignment of the output ports of the interferometer (output misalignment) only effects the high frequency part of the quantum noise limited sensitivity (detection noise). However, at low frequencies, HOMs reduce the interferometer response and the radiation pressure noise (back action noise) by the same amount and hence the quantum noise limited sensitivity is not negatively effected in that frequency range. We show that the misalignment of laser into the interferometer (input misalignment) produces the same effect as output misalignment and additionally decreases the power inside the interferometer. We also analyze dynamic HOM effects, such as beam jitter created by the suspended mirrors of the BHD. Our analyses can be directly applied to any BHD implementation in a future GWD. Moreover, we apply our analytical techniques to the example of the speed meter proof of concept experiment under construction in Glasgow. We find that for our experimental parameters, the performance of our seismic isolation system in the BHD paths is compatible with the design sensitivity of the experiment

Efficient Photon Upconversion Enabled by Strong Coupling Between Organic Molecules and Quantum Dots

Hybrid structures formed between organic molecules and inorganic quantum dots can accomplish unique photophysical transformations by taking advantage of their disparate properties. The electronic coupling between these materials is typically weak, leading photoexcited charge carriers to spatially localize to a dot or a molecule at its surface. However, we show that by converting a chemical linker that covalently binds anthracene molecules to silicon quantum dots from a carbon-carbon single bond to a double bond, we access a strong-coupling regime where excited carriers spatially delocalize across both anthracene and silicon. By pushing the system to delocalize, we design a photon upconversion system with a higher efficiency (17.2%) and lower threshold intensity (0.5 W/cm^2) than that of a corresponding weakly-coupled system. Our results show that strong coupling between molecules and nanostructures achieved through targeted linking chemistry provides a new route for tailoring properties in materials for light-driven applications.Comment: 33 pages (20 in main text, 13 in supporting information), 12 figures (5 in main text, 7 in supporting information

Demonstration of a switchable damping system to allow low-noise operation of high-Q low-mass suspension systems

Low mass suspension systems with high-Q pendulum stages are used to enable quantum radiation pressure noise limited experiments. Utilising multiple pendulum stages with vertical blade springs and materials with high quality factors provides attenuation of seismic and thermal noise, however damping of these high-Q pendulum systems in multiple degrees of freedom is essential for practical implementation. Viscous damping such as eddy-current damping can be employed but introduces displacement noise from force noise due to thermal fluctuations in the damping system. In this paper we demonstrate a passive damping system with adjustable damping strength as a solution for this problem that can be used for low mass suspension systems without adding additional displacement noise in science mode. We show a reduction of the damping factor by a factor of 8 on a test suspension and provide a general optimisation for this system.Comment: 5 pages, 5 figure

Symbiosal^®and lowering of blood pressure and reduced risk of hypertension:evaluation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006

Following an application from Han-Biotech GmbH, submitted for authorisation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006 via the Competent Authority of Germany, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim related to Symbiosal® , lowering of blood pressure and reduced risk of hypertension. The Panel considers that the food, Symbiosal® , which is the subject of the health claim, and the food, table salt, which Symbiosal® should replace, are sufficiently characterised. Lowering of blood pressure is a beneficial physiological effect. Increased blood pressure is a risk factor for hypertension. In weighing the evidence, the Panel took into account that one human study with some methodological limitations showed an effect of Symbiosal® on blood pressure in the context of a self-selected diet with a maximum of 3 g/day added salt. The Panel also took into account that no other human studies in which these results have been replicated were provided, that the animal studies did not support the results of the human study, that no evidence was provided in support of a mechanism by which Symbiosal® could induce a decrease in blood pressure upon oral consumption as compared to table salt in vivo in humans, and the low biological plausibility of the effect observed in the human intervention study. The Panel concludes that a cause and effect relationship has not been established between the consumption of Symbiosal® and lowering of blood pressure. </p