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PurposeThis paper aims to analyse through a bibliometric study the academic literature that relates entrepreneurship to foods.Design/methodology/approachA database of 1,300 papers published in the ISI Web of Science was generated. The bibliometric techniques allowed us to describe scientific literature evolution, most productive authors, institutions and countries, most relevant sources and documents, trend topics and social structure.FindingsThe results illustrate an upward trend, more accentuated in the last four years, in publishing papers relating entrepreneurship to the food industry.Originality/valueThis research is novel because although numerous articles relate the food industry to entrepreneurship, no bibliometric articles that analyse the scientific production that relates both terms have been found in the literature.

We evaluate the accuracy of the actuator line model (ALM) approach by performing simulations for the NREL~5~MW wind turbine in uniform inflow using three large eddy simulation codes. The power and thrust coefficients obtained using the three codes agrees within $1\%$ when the grid spacing $\Delta_{\rm grid} \le 5.25$~m, and are cross-validated against blade element momentum (BEM) theory. We find that the results of ALM converge towards BEM theory without the need for tip correction when the numerical resolution is increased. For $\Delta_{\rm grid}=0.98$~m the difference between the power and thrust coefficient obtained using ALM and BEM is $4.5\%$ and $2.1\%$, respectively, although we note that no absolute convergence between ALM and BEM can be obtained as both models use different assumptions, such as the use of a force projection method in the ALM. The difference in the local axial and tangential forces along the blades obtained from ALM simulations using $\Delta_{\rm grid} = 1.97$~m and $\Delta_{\rm grid} = 0.98$~m can be as large as $10\%$. The effect of the number of actuator points on the obtained turbine power and thrust coefficients is limited as the results converge when the spacing between the actuator points is about three times the grid spacing. This insight on the required number of blade points can be used to improve the efficiency of actuator line simulations., Comment: 13 pages, 8 figures

Objective Weight loss is one of the most common New Year's resolutions, but it is unclear whether attempting to lose weight in January is more successful than attempting it at other times of the year. Methods In this prospective cohort study from the English National Health Service (NHS) Diabetes Prevention Program, adults with nondiabetic hyperglycemia were enrolled in a structured behavioral weight management program. Repeated measures models assessed the mean difference between baseline and follow-up weight adjusting for monthly variation in weight among those with ≥1 weight measurement. Results Among 85,514 participants with a mean baseline BMI of 30.3 kg/m2 (range: 13.4 to 84.2), mean weight change at the end of the program after an average 7.9 (SD: 4.5) sessions over 6.4 (SD: 5.6) months was −2.00 kg (95% CI: −2.02 to −1.97 kg) or −2.33% (95% CI: −2.35% to −2.32%). Compared with participants starting in January, participants starting in other months lost less weight, ranging between 0.28 kg (95% CI: 0.10 to 0.45 kg) less weight in those starting in March and 0.71 kg (95% CI: 0.55 to 0.87 kg) less weight in those starting in November. April and May were the only exceptions, in which the estimates followed the same direction but were not statistically significant. Higher session attendance mediated the effects, with participants starting in January attending, on average, 0.2 to 0.7 more sessions than those starting in other months. Conclusions People starting a weight management program in January lost 12% to 30% more weight than people starting it at other times of the year.

Objective To develop and externally validate the STRAtifying Treatments In the multi-morbid Frail elderlY (STRATIFY)-Falls clinical prediction model to identify the risk of hospital admission or death from a fall in patients with an indication for antihypertensive treatment. Design Retrospective cohort study. Setting Primary care data from electronic health records contained within the UK Clinical Practice Research Datalink (CPRD). Participants Patients aged 40 years or older with at least one blood pressure measurement between 130 mm Hg and 179 mm Hg. Main outcome measure First serious fall, defined as hospital admission or death with a primary diagnosis of a fall within 10 years of the index date (12 months after cohort entry). Model development was conducted using a Fine-Gray approach in data from CPRD GOLD, accounting for the competing risk of death from other causes, with subsequent recalibration at one, five, and 10 years using pseudo values. External validation was conducted using data from CPRD Aurum, with performance assessed through calibration curves and the observed to expected ratio, C statistic, and D statistic, pooled across general practices, and clinical utility using decision curve analysis at thresholds around 10%. Results Analysis included 1 772 600 patients (experiencing 62 691 serious falls) from CPRD GOLD used in model development, and 3 805 366 (experiencing 206 956 serious falls) from CPRD Aurum in the external validation. The final model consisted of 24 predictors, including age, sex, ethnicity, alcohol consumption, living in an area of high social deprivation, a history of falls, multiple sclerosis, and prescriptions of antihypertensives, antidepressants, hypnotics, and anxiolytics. Upon external validation, the recalibrated model showed good discrimination, with pooled C statistics of 0.833 (95% confidence interval 0.831 to 0.835) and 0.843 (0.841 to 0.844) at five and 10 years, respectively. Original model calibration was poor on visual inspection and although this was improved with recalibration, under-prediction of risk remained (observed to expected ratio at 10 years 1.839, 95% confidence interval 1.811 to 1.865). Nevertheless, decision curve analysis suggests potential clinical utility, with net benefit larger than other strategies. Conclusions This prediction model uses commonly recorded clinical characteristics and distinguishes well between patients at high and low risk of falls in the next 1-10 years. Although miscalibration was evident on external validation, the model still had potential clinical utility around risk thresholds of 10% and so could be useful in routine clinical practice to help identify those at high risk of falls who might benefit from closer monitoring or early intervention to prevent future falls. Further studies are needed to explore the appropriate thresholds that maximise the model’s clinical utility and cost effectiveness.

Baroclinicity, which leads to height-dependent driving pressure gradients, occurs in various situations such as the flow transition between land and sea, and sloping terrain. It has been shown that baroclinicity modifies the structure of the atmospheric boundary layer. For example, negative shear baroclinicity creates additional turbulence at higher elevations, which might influence the energy entrainment into large wind farms. Here, we use large-eddy simulations to study the effect of baroclinicity-induced negative shear on the wind farm power production and energy entrainment into a large wind farm. In agreement with the literature, our simulations show that negative geostrophic wind shear significantly modifies the mean wind velocity in the atmospheric boundary layer. Specifically, for the cases considered in the study, the negative geostrophic shear causes a change in the mean velocity up to 2.3 m/s at hub height, which greatly alters the wind farm power production. Additionally, we demonstrate with an energy budget analysis that a wind farm does not necessarily benefit from the additional turbulence created by the negative geostrophic wind shear. The reason for this is that the baroclinicity-induced negative shear alters the height and strength of the low-level jet and creates an upward flux above the jet, limiting the energy entrainment into the wind farm. Our results show that wind resources are altered in the boundary layer due to negative geostrophic wind shear and should be considered in wind farm modeling and power forecasts.

We perform direct numerical simulations to study the effect of the gravity centre offset in spherical Rayleigh–Bénard convection. When the gravity centre is shifted towards the south, we find that the shift of the gravity centre has a pronounced influence on the flow structures. At low Rayleigh number $Ra$ , a steady-state large-scale meridional circulation induced by the baroclinic imbalance, created by the misalignment of the gravity potentials and isotherms, is formed. At high $Ra$ , an energetic jet is created on the northern side of the inner sphere that is directed towards the outer sphere. The large-scale circulation induces a strong co-latitudinal dependence in the local heat flux. Nevertheless, the global heat flux is not affected by the changes in the large-scale flow organization induced by the gravity centre offset.

Significance The presented model describes the vertical structure of conventionally neutral atmospheric boundary layers. Due to the complicated interplay between buoyancy, shear, and Coriolis effects, analytical descriptions have been limited to the mean wind speed. We introduce an analytical approach based on the Ekman equations and the basis function of the universal potential temperature flux profile that allows one to describe the wind and turbulent shear stress profiles and hence capture features like the wind veer profile. The analytical profiles are validated against high-fidelity large-eddy simulations and atmospheric measurements. Our findings contribute to the scientific community’s fundamental understanding of atmospheric turbulence with direct relevance for weather forecasting, climate modeling, and wind energy applications.

We report on the mobility and orientation of finite-size, neutrally buoyant prolate ellipsoids (of aspect ratio $\Lambda=4$) in Taylor-Couette flow, using interface resolved numerical simulations. The setup consists of a particle-laden flow in between a rotating inner and a stationary outer cylinder. We simulate two particle sizes $\ell/d=0.1$ and $\ell/d=0.2$, $\ell$ denoting the particle major axis and $d$ the gap-width between the cylinders. The volume fractions are $0.01\%$ and $0.07\%$, respectively. The particles, which are initially randomly positioned, ultimately display characteristic spatial distributions which can be categorised into four modes. Modes $(i)$ to $(iii)$ are observed in the Taylor vortex flow regime, while mode ($iv$) encompasses both the wavy vortex, and turbulent Taylor vortex flow regimes. Mode $(i)$ corresponds to stable orbits away from the vortex cores. Remarkably, in a narrow $\textit{Ta}$ range, particles get trapped in the Taylor vortex cores (mode ($ii$)). Mode $(iii)$ is the transition when both modes $(i)$ and $(ii)$ are observed. For mode $(iv)$, particles distribute throughout the domain due to flow instabilities. All four modes show characteristic orientational statistics. We find the particle clustering for mode ($ii$) to be size-dependent, with two main observations. Firstly, particle agglomeration at the core is much higher for $\ell/d=0.2$ compared to $\ell/d=0.1$. Secondly, the $\textit{Ta}$ range for which clustering is observed depends on the particle size. For this mode $(ii)$ we observe particles to align strongly with the local cylinder tangent. The most pronounced particle alignment is observed for $\ell/d=0.2$ around $\textit{Ta}=4.2\times10^5$. This observation is found to closely correspond to a minimum of axial vorticity at the Taylor vortex core ($\textit{Ta}=6\times10^5$) and we explain why., Comment: 22 pages, 12 figures

We investigate the counter-intuitive initial decrease and subsequent increase in the Nusselt number $Nu$ with increasing wall Reynolds number $Re_w$ in the sheared Rayleigh–Bénard (RB) system by studying the energy spectra of convective flux and turbulent kinetic energy for Rayleigh number $Ra = 10^{7}$ , Prandtl number $Pr=1.0$ and inverse Richardson numbers $0 \leq 1/Ri \leq 10$ . These energy spectra show two distinct high-energy regions corresponding to the large-scale superstructures in the bulk and small-scale structures in the boundary layer (BL) regions. A greater separation between these scales at the thermal BL height correlates to a higher $Nu$ and indicates that the BLs are more turbulent. The minimum $Nu$ , which occurs at $1/Ri=1.0$ , is accompanied by the smallest separation between the large- and small-scale structures at the thermal BL height. At $1/Ri=1.0$ , we also observe the lowest value of turbulent kinetic energy normalized with the square of friction velocity within the thermal BL. Additionally, we find that the domain size has a limited effect on the heat and momentum transfer in the sheared RB system as long as the domain can accommodate the small-scale convective structures at the thermal BL height, signifying that capturing the large-scale superstructures is not essential to obtain converged values of $Nu$ and shear Reynolds number $Re_{\tau }$ . When the domain is smaller than these small-scale convective structures, the overall heat and momentum transfer reduces drastically.

We performed large-eddy simulations in a neutral atmospheric boundary layer to study the interaction between two identical wind farms with 72 turbines each. We demonstrate that the wind farm wake created by the upstream farm affects the entire flow in and around the downstream farm. The vertical entrainment fluxes above the downstream wind farm are strengthened, resulting in a faster wind farm wake recovery behind the downstream farm. These findings illustrate that interaction between extended wind farms affects flow structures beyond the wind farm scale. Furthermore, we demonstrate that wind farm wakes can reduce the power production of turbines throughout the downstream wind farms. We additionally observe that a staggered wind farm extracts more energy from the flow and thus creates a stronger wind farm wake than an aligned wind farm.

A good understanding of wind turbine noise propagation is relevant to better measure the impact of turbines on the environment. In this study, we developed numerical simulations to study the impact of a 2D hill on the sound propagation for a turbine in non flat terrain. The simulations employed a propagation model derived from the linearized Euler equations, solved in a moving frame following the wavefront. The wind turbine noise was modeled using a point source approach. The flow structure in the atmospheric boundary layer and the wind turbine wake were obtained from large-eddy simulations. We find that the wind turbine wake acts as a waveguide that focuses sound propagation towards the ground. This effect is most pronounced for the flat terrain case and when the turbine is placed on the hill. The sound attenuation is more localized and closer to the turbine when the wind turbine is placed on the hilltop than in the flat case. As the wind speed increases, the sound focusing is observed closer to the turbine. For a turbine placed in front of the hill, the sound propagation is mainly determined by the flow over the hill. This demonstrates that terrain topography can have surprising effects on wind turbine noise propagation., Comment: 14 pages, 17 figures

Even before the COVID-19 pandemic, attending to the mental wellbeing of all doctors was high on the political agenda. The quality of patient care is also known to be related to doctors’ wellbeing. Now, in the midst of a global pandemic, doctors are having to cope with ever more trauma and moral injury. Group-based peer support and regular reflective practice are interventions known to reduce clinician burnout and optimise wellbeing. Junior doctors are the most likely of all medical groups to be at a high risk of burnout. The NHS Staff and Learners’ Mental Wellbeing Commission report advocates establishing explicit peer support mechanisms and the use of peer support as part of the first line of psychological first aid. Peer support is not addressed in the curriculum for the majority of medical specialties. We recommend that regular peer-support reflective groups are provided during protected time for all trainees.