The effects of a diet and feeding frequency on peripheral nutrient supply and growth traits of the lamb

Tissue protein synthesis requires a simultaneous supply of energy and amino acids. The effect of altering diet and frequency of feeding on patterns of amino acid and acetate supply to peripheral tissues and the consequent effects on growth and carcass composition was investigated in growing lambs. A rumen 'asynchronous' diet with respect to the ratio of the rate of release of organic matter (OM) and nitrogen (N) was fed once daily (AD) or hourly (AR) and a more 'synchronous' diet was fed once daily (SD) to individually penned growing lambs (n=30) for 16 weeks. Plasma concentrations of acetate, amino acids and insulin were more constant throughout the day in animals fed AH compared to those fed AD. Those fed SD or AD had similar, large pulses in plasma acetate concentration following feeding. Animals fed AH had increased growth rates and greater amounts of carcass crude protein compared to those fed AD (PO.1). Synchronous diets formulated to have either slow (SS) or fast (FP) release of OM and N into the rumen were fed hourly (SSH or FFH) or once daily (SSD or FFD) to individually penned growing lambs (n=28) for 10 weeks. Plasma concentrations of acetate and insulin in groups fed once daily, increased after feeding, remaining elevated for longer in animals fed SSD. Amino acid concentrations decreased following feeding. Once daily fed animals tended to have greater amounts of crude protein in the carcass and generally heavier muscles than those fed hourly, particularly those fed SS. Animals fed AH had significantly higher feed intakes in the first experiment compared to those fed the diets once daily (P<O.OO1) which may be why these animals grew better and deposited more carcass protein than those fed once daily. It was thought that a pulse in acetate following feeding may contribute to an enhanced growth and carcass protein in ruminants. When sodium acetate was infused into growing lambs, intravenously, to raise the concentrations of plasma acetate similar to the pulse in acetate concentrations observed in the plasma of sheep following once daily feeding, no increase in whole-body protein synthesis was observed. The effect of temporal changes in the peripheral nutrient supply on protein synthesis in the ruminant requires further investigation

The effects of a diet and feeding frequency on peripheral nutrient supply and growth traits of the lamb

Tissue protein synthesis requires a simultaneous supply of energy and amino acids. The effect of altering diet and frequency of feeding on patterns of amino acid and acetate supply to peripheral tissues and the consequent effects on growth and carcass composition was investigated in growing lambs. A rumen 'asynchronous' diet with respect to the ratio of the rate of release of organic matter (OM) and nitrogen (N) was fed once daily (AD) or hourly (AR) and a more 'synchronous' diet was fed once daily (SD) to individually penned growing lambs (n=30) for 16 weeks. Plasma concentrations of acetate, amino acids and insulin were more constant throughout the day in animals fed AH compared to those fed AD. Those fed SD or AD had similar, large pulses in plasma acetate concentration following feeding. Animals fed AH had increased growth rates and greater amounts of carcass crude protein compared to those fed AD (PO.1). Synchronous diets formulated to have either slow (SS) or fast (FP) release of OM and N into the rumen were fed hourly (SSH or FFH) or once daily (SSD or FFD) to individually penned growing lambs (n=28) for 10 weeks. Plasma concentrations of acetate and insulin in groups fed once daily, increased after feeding, remaining elevated for longer in animals fed SSD. Amino acid concentrations decreased following feeding. Once daily fed animals tended to have greater amounts of crude protein in the carcass and generally heavier muscles than those fed hourly, particularly those fed SS. Animals fed AH had significantly higher feed intakes in the first experiment compared to those fed the diets once daily (P<O.OO1) which may be why these animals grew better and deposited more carcass protein than those fed once daily. It was thought that a pulse in acetate following feeding may contribute to an enhanced growth and carcass protein in ruminants. When sodium acetate was infused into growing lambs, intravenously, to raise the concentrations of plasma acetate similar to the pulse in acetate concentrations observed in the plasma of sheep following once daily feeding, no increase in whole-body protein synthesis was observed. The effect of temporal changes in the peripheral nutrient supply on protein synthesis in the ruminant requires further investigation

A Welsh Collection of Mendelssohniana: Letters at Aberystwyth

Evans, Todd, and Olsen review letters by great musicians held in the Hugh Owen Library of the University College of Wales, Aberystwyth

Relations Among Correlation Functions in the High Temperature Phase of QCD with Broken SU(3)

Group-theoretic arguments are used to determine the dependence of two-point correlators of quark bilinears on the current quark masses. The leading difference between $\pi$ and $\delta$ correlators is found to be of order $m_s$ times a U(1)$_{\scriptscriptstyle A}$-violating correlator. These general arguments are consistent with Schaefer's observation that if U(1)$_{\scriptscriptstyle A}$ violation persists to high enough temperatures then the strange $\eta$ can be lighter than the non-strange one.Comment: 8 page

Multimodal Control of Liquid Crystalline Mesophases from Surfactants with Photoswitchable Tails

Non-invasive manipulation of the hierarchical structure of functional materials is a key challenge in the advancement of optoelectronics, energy conversion and storage devices and drug delivery systems. Here, using a combination of small-angle X-ray scattering and polarised optical microscopy, we decipher the various structure/self- assembly relationships of neutral surfactants bearing photoswitchable tails, which self-organise into a rich variety of lyotropic liquid crystalline mesophases. Facile, multimodal control of the nanoscale morphology of these single-component systems is achieved through: i) molecular structure, via careful selection of the alkyl tail/ethylene oxide headgroup lengths; ii) concentration; iii) temperature; and iv) photoisomerisation. The nanoscale architectures range from the weakly concentrated hyperswollen lamellar phases, the more common lyotropic lamellar and hexagonal phases, to pure thermotropic liquid crystals; all of which are accessible at room temperature. Photoisomerisation with UV light leads to the reversible destruction of the liquid crystalline phase, which can be spatially controlled through the use of a mask. This extensive study demonstrates the versatility of neutral photosurfactants and paves the way for them to be investigated for new applications, such as photoresponsive templates or drug delivery systems.Isaac Newton Trust/University of Cambridge Early Career Support Scheme grant. Irish Research Council EU COST action MP120

Light-responsive self-assembly of a cationic azobenzene surfactant at high concentration.

The formation of high-concentration mesophases by a cationic azobenzene photosurfactant is described for the first time. Using a combination of polarised optical microscopy and small-angle X-ray scattering, optically anisotropic, self-assembled structures with long-range order are reported. The mesophases are disrupted or lost upon UV irradiation

The Use of unregulated staff: Time for regulation?

Internationally, shortages in the nursing workforce, escalating patient demands, and financial constraints within the health system have led to the growth of unlicensed nursing support workers. Recently, in relation to the largest publicly funded health system (National Health Service), it was reported that extensive substitution of registered nurses with unskilled nursing support workers resulted in inadequate patient care, increased morbidity and mortality rates, and negative nurse outcomes. We argue that it is timely to consider regulation of nursing support workers with their role and scope of practice clearly defined. Further, the addition of these workers in a complementary model of care (rather than substitutive model) should also be explored in future research, in terms of impact on patient and nurse outcomes

Probing the dynamic self-assembly behaviour of photoswitchable wormlike micelles in real-time.

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such as drug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis- and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, tetraethylene glycol mono(4',4-octyloxy,octyl-azobenzene) (C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in situ UV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4 could switch between wormlike micelles (trans native state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in situ through combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly

A single-component photorheological fluid with light-responsive viscosity.

Viscoelastic fluids whose rheological properties are tunable with light have the potential to deliver significant impact in fields relying on a change in flow behavior, such as in-use tuning of combined efficient heat-transfer and drag-reduction agents, microfluidic flow and controlled encapsulation and release. However, simple, single-component systems must be developed to allow integration with these applications. Here, we report a single-component viscoelastic fluid, capable of a dramatic light-sensitive rheological response, from a neutral azobenzene photosurfactant, 4-hexyl-4'butyloxymonotetraethylene glycol (C6AzoOC4E4) in water. From cryo-transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS) and rheology measurements, we observe that the photosurfactant forms an entangled network of wormlike micelles in water, with a high viscosity (28 Pa s) and viscoelastic behaviour. UV irradiation of the surfactant solution creates a less dense micellar network, with some vesicle formation. As a result, the solution viscosity is reduced by four orders of magnitude (to 1.2 × 10-3 Pa s). This process is reversible and the high and low viscosity states can be cycled several times, through alternating UV and blue light irradiation