The mean free path for electron conduction in metallic fullerenes

We calculate the electrical resistivity due to electron-phonon scattering for a model of A3C60 (A= K, Rb), using an essentially exact quantum Monte-Carlo calculation. In agreement with experiment, we obtain exceptionally large metallic resistivities at large temperatures T. This illustrates that the apparent mean free path can be much shorter than the separation of the molecules. An interpretation of this result is given. The calculation also explains the linear behavior in T at small T.Comment: 4 pages, RevTeX, 3 eps figure, additional material available at http://www.mpi-stuttgart.mpg.de/docs/ANDERSEN/fullerene

Association of postprandial postexercise muscle protein synthesis rates with dietary leucine: A systematic review.

This is the final version. Available from Wiley via the DOI in this record. DATA AVAILABILITY STATEMENT: The datasets generated and/or analyzed during the study implementation are available from the corresponding author upon request.BACKGROUND: Dietary protein ingestion augments post (resistance) exercise muscle protein synthesis (MPS) rates. It is thought that the dose of leucine ingested within the protein (leucine threshold hypothesis) and the subsequent plasma leucine variables (leucine trigger hypothesis; peak magnitude, rate of rise, and total availability) determine the magnitude of the postprandial postexercise MPS response. METHODS: A quantitative systematic review was performed extracting data from studies that recruited healthy adults, applied a bout of resistance exercise, ingested a bolus of protein within an hour of exercise, and measured plasma leucine concentrations and MPS rates (delta change from basal). RESULTS: Ingested leucine dose was associated with the magnitude of the MPS response in older, but not younger, adults over acute (0-2 h, r2  = 0.64, p = 0.02) and the entire postprandial (>2 h, r2  = 0.18, p = 0.01) period. However, no single plasma leucine variable possessed substantial predictive capacity over the magnitude of MPS rates in younger or older adults. CONCLUSION: Our data provide support that leucine dose provides predictive capacity over postprandial postexercise MPS responses in older adults. However, no threshold in older adults and no plasma leucine variable was correlated with the magnitude of the postexercise anabolic response.Beachbody LL

A case study of implementing interprofessional education in care home settings

Purpose: The purpose of this paper is to report on an interprofessional (IPE) student training scheme recently conducted in three care homes across the Northwest of England. The intervention was designed as a feasibility study to explore the impacts such schemes have on residents, students and care home staff. Additional lessons emerged that contribute to the design and direction of future IPE initiatives in other care homes and care settings. Design/methodology/approach: This case study outlines how the intervention was designed and implemented and the findings from its evaluation. This paper uses Biggs’ (1993) presage–process–product framework to evaluate the process of setting up care homes as a site of collaborative learning. Findings: Collaborative working between stakeholders is necessary for the successful implementation of IPE in care home settings. The process is complex and requires communication and commitment across all levels of engagement. For this model to grow and have a beneficial impact on older people’s lives, there are layered factors to consider, such as the socio-political context, the characteristics of the individuals who participate and diverse approaches to learning. Research limitations/implications: This case study reports the subjective views of the research collaborators. While this raises the potential for bias, it presents an “insider” perspective of the research process and offers learning that might be beneficial in efforts to run future IPE training schemes. Originality/value: To the best of the authors’ knowledge, no other research studies or published interventions have been identified that explicitly address the experiences of implementing an IPE training scheme in UK care home settings. This paper will therefore be useful to academic researchers, individuals managing student placements and to health and social care staff who wish to learn about of the value of IPE learning schemes

Nutritional considerations for the vegan athlete.

This is the final version. Available from Elsevier via the DOI in this record. Accepting a continued rise in the prevalence of vegan-type diets in the general population is also likely to occur in athletic populations, it is of importance to assess the potential impact on athletic performance, adaptation, and recovery. Nutritional consideration for the athlete requires optimization of energy, macronutrient, and micronutrient intakes, and potentially the judicious selection of dietary supplements, all specified to meet the individual athlete's training and performance goals. The purpose of this review is to assess whether adopting a vegan diet is likely to impinge on such optimal nutrition and, where so, consider evidence based yet practical and pragmatic nutritional recommendations. Current evidence does not support that a vegan-type diet will enhance performance, adaptation, or recovery in athletes, but equally suggests that an athlete can follow a (more) vegan diet without detriment. A clear caveat, however, is that vegan diets consumed spontaneously may induce suboptimal intakes of key nutrients, most notably quantity and/or quality of dietary protein and specific micronutrients (eg, iron, calcium, vitamin B12, and vitamin D). As such, optimal vegan sports nutrition requires (more) careful consideration, evaluation, and planning. Individual/seasonal goals, training modalities, athlete type, and sensory/cultural/ethical preferences, among other factors, should all be considered when planning and adopting a vegan diet.Marlow Foods Ltd

Short-term disuse does not affect postabsorptive or postprandial muscle protein fractional breakdown rates

This is the final version. Available on open access from Wiley via the DOI in this recordBACKGROUND: The decline in postabsorptive and postprandial muscle protein fractional synthesis rates (FSR) does not quantitatively account for muscle atrophy during uncomplicated, short-term disuse, when atrophy rates are the highest. We sought to determine whether 2 days of unilateral knee immobilization affects mixed muscle protein fractional breakdown rates (FBR) during postabsorptive and simulated postprandial conditions. METHODS: Twenty-three healthy, male participants (age: 22 ± 1 year; height: 179 ± 1 cm; body mass: 73.4 ± 1.5 kg; body mass index 22.8 ± 0.5 kg·m-2 ) took part in this randomized, controlled study. After 48 h of unilateral knee immobilization, primed continuous intravenous l-[15 N]-phenylalanine and l-[ring-2 H5 ]-phenylalanine infusions were used for parallel determinations of FBR and FSR, respectively, in a postabsorptive (saline infusion; FAST) or simulated postprandial state (67.5 mg·kg body mass-1 ·h-1 amino acid infusion; FED). Bilateral m. vastus lateralis biopsies from the control (CON) and immobilized (IMM) legs, and arterialized-venous blood samples, were collected throughout. RESULTS: Amino acid infusion rapidly increased plasma phenylalanine (59 ± 9%), leucine (76 ± 5%), isoleucine (109 ± 7%) and valine (42 ± 4%) concentrations in FED only (all P  0.05). However, immobilization decreased FSR (P < 0.05) in both FAST (0.071 ± 0.004 vs. 0.086 ± 0.007%·h-1 ; IMM vs CON, respectively) and FED (0.066 ± 0.016 vs. 0.119 ± 0.016%·h-1 ; IMM vs CON, respectively). Consequently, immobilization decreased net muscle protein balance (P < 0.05) and to a greater extent in FED (CON: -0.012 ± 0.025; IMM: -0.095 ± 0.023%·h-1 ; P < 0.05) than FAST (CON: -0.064 ± 0.020; IMM: -0.072 ± 0.017%·h-1 ). CONCLUSIONS: We conclude that merely 2 days of leg immobilization does not modulate postabsorptive and simulated postprandial muscle protein breakdown rates. Instead, under these conditions the muscle negative muscle protein balance associated with brief periods of experimental disuse is driven near exclusively by reduced basal muscle protein synthesis rates and anabolic resistance to amino acid administration.Nutricia Research FoundationUniversity of ExeterBeachbody LLCNational Institute of Agin

Algae Ingestion Increases Resting and Exercised Myofibrillar Protein Synthesis Rates to a Similar Extent as Mycoprotein in Young Adults

This is the final version. Available on open access from Elsevier via the DOI in this recordData availability: Data described in the manuscript may be made available upon request, pending application.BACKGROUND: Spirulina [SPIR] (cyanobacterium) and chlorella [CHLO] (microalgae) are foods rich in protein and essential amino acids; however, their capacity to stimulate myofibrillar protein synthesis (MyoPS) in humans remains unknown. OBJECTIVES: We assessed the impact of ingesting SPIR and CHLO compared with an established high-quality nonanimal-derived dietary protein source (fungal-derived mycoprotein [MYCO]) on plasma amino acid concentrations, as well as resting and postexercise MyoPS rates in young adults. METHODS: Thirty-six healthy young adults (age: 22 ± 3 y; BMI: 23 ± 3 kg·m-2; male [m]/female [f], 18/18) participated in a randomized, double-blind, parallel-group trial. Participants received a primed, continuous infusion of L-[ring-2H5]-phenylalanine and completed a bout of unilateral-resistance leg exercise before ingesting a drink containing 25 g protein from MYCO (n = 12; m/f, 6/6), SPIR (n = 12; m/f, 6/6), or CHLO (n = 12; m/f, 6/6). Blood and bilateral muscle samples were collected at baseline and during a 4-h postprandial and postexercise period to assess the plasma amino acid concentrations and MyoPS rates in rested and exercised tissue. RESULTS: Protein ingestion increased the plasma total and essential amino acid concentrations (time effects; all P 0.05), but with higher rates in exercised compared with rested muscle (time × exercise effect; P < 0.001). CONCLUSIONS: The ingestion of a single bolus of algae-derived SPIR and CHLO increases resting and postexercise MyoPS rates to a comparable extent as MYCO, despite divergent postprandial plasma amino acid responses

Daily mycoprotein consumption for one week does not affect insulin sensitivity or glycaemic control but modulates the plasma lipidome in healthy adults: a randomised controlled trial

This is the author accepted manuscript. The final version is available from Cambridge University Press via the DOI in this record.Mycoprotein consumption has been shown to improve acute postprandial glycaemic control and decrease circulating cholesterol concentrations. We investigated the impact of incorporating mycoprotein into the diet on insulin sensitivity (IS), glycaemic control and plasma lipoprotein composition. Twenty healthy adults participated in a randomised, parallel-group trial in which they consumed a 7 d fully-controlled diet where lunch and dinner contained either meat/fish (CON) or mycoprotein (MYC) as the primary source of dietary protein. Oral glucose tolerance tests were performed pre- and post- intervention, and 24h continuous blood glucose monitoring was applied throughout. Fasting plasma samples were obtained pre- and post- intervention and were analysed using quantitative, targeted NMR-based metabonomics. There were no changes within or between groups in blood glucose or serum insulin responses, nor in IS (Cederholm; 51±3 to 51±3 and 54±3 to 53±3 mg.L2/mmol.mU.min in CON and MYC, respectively; P<0.05) or 24 h glycaemic profiles. No differences between groups were found for 171 of the 224 metabonomic targets. Forty five lipid concentrations of different lipoprotein fractions (VLDL, LDL, IDL and HDL) remained unchanged in CON but showed a coordinated decrease (7-27 %; all P<0.05) in MYC. Total plasma cholesterol, free-C, LDL-C, HDL2-C, DHA and omega-3 fatty acids decreased to a larger degree in MYC (14-19 %) compared with CON (3-11 %; P<0.05). Substituting meat/fish for mycoprotein twice-daily for one week did not modulate whole-body IS or glycaemic control but resulted in changes to plasma lipid composition; the latter primarily consisting of a coordinated reduction in circulating cholesterol containing lipoproteins.QuornMarlow Foods Lt

Counting defects with the two-point correlator

We study how topological defects manifest themselves in the equal-time two-point field correlator. We consider a scalar field with Z_2 symmetry in 1, 2 and 3 spatial dimensions, allowing for kinks, domain lines and domain walls, respectively. Using numerical lattice simulations, we find that in any number of dimensions, the correlator in momentum space is to a very good approximation the product of two factors, one describing the spatial distribution of the defects and the other describing the defect shape. When the defects are produced by the Kibble mechanism, the former has a universal form as a function of k/n, which we determine numerically. This signature makes it possible to determine the kink density from the field correlator without having to resort to the Gaussian approximation. This is essential when studying field dynamics with methods relying only on correlators (Schwinger-Dyson, 2PI).Comment: 11 pages, 7 figures

Determinants of the voltage dependence of G protein modulation within calcium channel β subunits

CaVβ subunits of voltage-gated calcium channels contain two conserved domains, a src-homology-3 (SH3) domain and a guanylate kinase-like (GK) domain with an intervening HOOK domain. We have shown in a previous study that, although Gβγ-mediated inhibitory modulation of CaV2.2 channels did not require the interaction of a CaVβ subunit with the CaVα1 subunit, when such interaction was prevented by a mutation in the α1 subunit, G protein modulation could not be removed by a large depolarization and showed voltage-independent properties (Leroy et al., J Neurosci 25:6984–6996, 2005). In this study, we have investigated the ability of mutant and truncated CaVβ subunits to support voltage-dependent G protein modulation in order to determine the minimal domain of the CaVβ subunit that is required for this process. We have coexpressed the CaVβ subunit constructs with CaV2.2 and α2δ-2, studied modulation by the activation of the dopamine D2 receptor, and also examined basal tonic modulation. Our main finding is that the CaVβ subunit GK domains, from either β1b or β2, are sufficient to restore voltage dependence to G protein modulation. We also found that the removal of the variable HOOK region from β2a promotes tonic voltage-dependent G protein modulation. We propose that the absence of the HOOK region enhances Gβγ binding affinity, leading to greater tonic modulation by basal levels of Gβγ. This tonic modulation requires the presence of an SH3 domain, as tonic modulation is not supported by any of the CaVβ subunit GK domains alone

Ingestion of mycoprotein, pea protein, and their blend support comparable postexercise myofibrillar protein synthesis rates in resistance-trained individuals.

This is the final version. Available from the American Physiological Society via the DOI in this record. DATA AVAILABILITY: Data described in the manuscript may be made available upon request, pending application.Pea protein is an attractive nonanimal-derived protein source to support dietary protein requirements. However, although high in leucine, a low methionine content has been suggested to limit its anabolic potential. Mycoprotein has a complete amino acid profile which, at least in part, may explain its ability to robustly stimulate myofibrillar protein synthesis (MyoPS) rates. We hypothesized that an inferior postexercise MyoPS response would be seen following ingestion of pea protein compared with mycoprotein, which would be (partially) rescued by blending the two sources. Thirty-three healthy, young [age: 21 ± 1 yr, body mass index (BMI): 24 ± 1 kg·m-2] and resistance-trained participants received primed, continuous infusions of l-[ring-2H5]phenylalanine and completed a bout of whole body resistance exercise before ingesting 25 g of protein from mycoprotein (MYC, n = 11), pea protein (PEA, n = 11), or a blend (39% MYC, 61% PEA) of the two (BLEND, n = 11). Blood and muscle samples were taken pre-, 2 h, and 4 h postexercise/protein ingestion to assess postabsorptive and postprandial postexercise myofibrillar protein fractional synthetic rates (FSRs). Protein ingestion increased plasma essential amino acid and leucine concentrations (time effect; P 0.05). These data show that all three nonanimal-derived protein sources have utility in supporting postexercise muscle reconditioning.NEW & NOTEWORTHY This study provides evidence that pea protein (PEA), mycoprotein (MYC), and their blend (BLEND) can support postexercise myofibrillar protein synthesis rates following a bout of whole body resistance exercise. Furthermore, these data suggest that a methionine deficiency in pea may not limit its capacity to stimulate an acute increase in muscle protein synthesis (MPS).National Institute of AgingMarlow Foods Ltd