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We consider the cylindrical bending problem for an infinite plate as modeled with a family of generalized continuum models, including the micromorphic approach. The models allow to describe length scale effects in the sense that thinner specimens are comparatively stiffer. We provide the analytical solution for each case and exhibits the predicted bending stiffness. The relaxed micromorphic continuum shows bounded bending stiffness for arbitrary thin specimens, while classical micromorphic continuum or gradient elasticity as well as Cosserat models (Neff et al. in Acta Mechanica 211(3–4):237–249, 2010) exhibit unphysical unbounded bending stiffness for arbitrary thin specimens. This finding highlights the advantage of using the relaxed micromorphic model, which has a definite limit stiffness for small samples and which aids in identifying the relevant material parameters.

We derive analytical solutions for the uniaxial extension problem for the relaxed micromorphic continuum and other generalized continua. These solutions may help in the identification of material parameters of generalized continua which are able to disclose size effects.

Various micro-scale models for comparing alternative design concepts have been developed in recent decades. The objective of this study is to provide an overview of current user-friendly micro-climate models. In the results, a vast majority of models identified were excluded from the review because the models were not micro-scale, lacking a user-interface, or were not available. In total, eight models met the seven-point inclusion criteria. These models were ADMS Temperature and Humidity model, advanced SkyHelios model, ANSYS FLUENT, ENVI-met, RayMan, SOLWEIG, TownScope, and UMEP. These models differ in their complexity and their widespread use in the scientific community, ranging from very few to thousands of citations. Most of these models simulate air temperature, global radiation, and mean radiant temperature, which helps to evaluate outdoor thermal comfort in cities. All of these models offer a linkage to CAD or GIS software and user support systems at various levels, which facilitates a smooth integration to planning and design. We detected that all models have been evaluated against observations. A wider model comparison, however, has only been performed for fewer models. With this review, we aim to support the finding of a reliable tool, which is fit for the specific purpose.

Mesenchymal stromal cell (MSC)‐derived small extracellular vesicles (sEVs) show therapeutic potential in multiple disease models, including kidney injury. Clinical translation of sEVs requires further preclinical and regulatory developments, including elucidation of the biodistribution and mode of action (MoA). Biodistribution can be determined using labelled sEVs in animal models which come with ethical concerns, are time‐consuming and expensive, and may not well represent human physiology. We hypothesised that, based on developments in microfluidics and human organoid technology, in vitro multi‐organ‐on‐a‐chip (MOC) models allow us to study effects of sEVs in modelled human organs like kidney and liver in a semi‐systemic manner. Human kidney‐ and liver organoids combined by microfluidic channels maintained physiological functions, and a kidney injury model was established using hydrogenperoxide. MSC‐sEVs were isolated, and their size, density and potential contamination were analysed. These sEVs stimulated recovery of the renal epithelium after injury. Microscopic analysis shows increased accumulation of PKH67‐labelled sEVs not only in injured kidney cells, but also in the unharmed liver organoids, compared to healthy control conditions. In conclusion, this new MOC model recapitulates therapeutic efficacy and biodistribution of MSC‐sEVs as observed in animal models. Its human background allows for in‐depth analysis of the MoA and identification of potential side effects.

In inland water covering lakes, reservoirs, and ponds, the gas exchange of slightly soluble gases such as carbon dioxide, dimethyl sulfide, methane, or oxygen across a clean and nearly flat air‐water interface is routinely described using a water‐side mean gas transfer velocity kL‾$\\overline{{k}_{L}}$ , where overline indicates time or ensemble averaging. The micro‐eddy surface renewal model predicts kL‾=αoSc−1/2νϵ‾1/4$\\overline{{k}_{L}}={\\alpha }_{o}S{c}^{-1/2}{\\left(\\nu \\overline{{\\epsilon}}\\right)}^{1/4}$ , where Sc$Sc$is the molecular Schmidt number, ν$\\nu $is the water kinematic viscosity, and ϵ‾$\\overline{{\\epsilon}}$is the waterside mean turbulent kinetic energy dissipation rate at or near the interface. While αo=0.39−0.46${\\alpha }_{o}=0.39-0.46$has been reported across a number of data sets, others report large scatter or variability around this value range. It is shown here that this scatter can be partly explained by high temporal variability in instantaneous ϵ${\\epsilon}$around ϵ‾$\\overline{{\\epsilon}}$ , a mechanism that was not previously considered. As the coefficient of variation CVe$\\left(C{V}_{e}\\right)$in ϵ${\\epsilon}$increases, αo${\\alpha }_{o}$must be adjusted by a multiplier 1+CVe2−3/32${\\left(1+C{V}_{e}^{2}\\right)}^{-3/32}$that was derived from a log‐normal model for the probability density function of ϵ${\\epsilon}$ . Reported variations in αo${\\alpha }_{o}$with a macro‐scale Reynolds number can also be partly attributed to intermittency effects in ϵ${\\epsilon}$ . Such intermittency is characterized by the long‐range (i.e., power‐law decay) spatial auto‐correlation function of ϵ${\\epsilon}$ . That αo${\\alpha }_{o}$varies with a macro‐scale Reynolds number does not necessarily violate the micro‐eddy model. Instead, it points to a coordination between the macro‐ and micro‐scales arising from the transfer of energy across scales in the energy cascade. Plain Language Summary In inland water, the movement of slightly soluble gas molecules such as carbon dioxide, methane or oxygen across an air‐water interface is of significance to a plethora of applications in aquatic ecology, climate sciences, and limnology. The standard model, known as the micro‐eddy model, considers water packets ejected from deeper levels within an inland water body, making contact with a clean and nearly flat air‐water surface, exchanging molecules with the atmosphere, and subsequently sweeping back down. Under a set of restrictive assumptions about the statistics of contact duration and their inference from water‐side velocity statistics near the surface, prediction of the efficiency of the exchange process can be made and encoded in a so‐called gas transfer velocity. The work here demonstrates that this gas transfer velocity can be derived by assuming a turnover velocity of these water packets that follows a universal form based on a widely accepted theory of energy transfer across scales and contemporary refinements to it. Key Points The micro‐eddy model (MEM) operationally describes the air‐water gas transfer velocity kL$\\left({k}_{L}\\right)$for slightly soluble gases The MEM leads to kL${k}_{L}$being proportional to the Kolmogorov micro‐scale velocity vk$\\left({v}_{k}\\right)$Increased variability and intermittency in the turbulent kinetic energy dissipation rate act to reduce kL${k}_{L}$for the same vk${v}_{k}$

Blood capillaries deliver oxygen and nutrients to surrounding micro-regions of tissue and carry away metabolic waste. In normal tissue, capillaries are close enough to keep all the cells viable. In solid tumours, the capillary system is chaotic and typical inter-capillary distances are larger than in normal tissue. Therefore, hypoxic regions develop. Drug molecules may not reach these areas at concentrations above the lethal level. The combined effect of low drug concentrations and local hypoxia, often exacerbated by acidity, leads to therapy failure. To better understand the interplay between hypoxia and poor drug penetration, oxygenation needs to be assessed in different areas of inter-capillary tissue. The multicellular tumour spheroid is a well-established three-dimensional (3D) in vitro model of the capillary microenvironment. It is used to mimic nascent tumours and micro-metastases as well. In this work, we demonstrate for the first time that dynamic intra-spheroidal oxygen maps can be obtained at the 3D multicellular tumour hemi-spheroid (MCH) using a non-invasive microelectrode array. The same oxygen distributions exist inside the equivalent but less accessible full spheroid. The MCH makes high throughput—high content analysis of spheroids feasible and thus can assist studies on basic cancer biology, drug development and personalized medicine.

Although there is now widespread evidence of substantial variability in economic agents’ responses to economic drivers in many applied economics fields, this variability has been largely overlooked by econometric agricultural production models. This article sets out to fill this gap by providing methodological contributions and empirical results. First, we consider panel data multicrop models featuring random intercept and slope parameters to account for the heterogeneous responses of crop producers to economic drivers. Second, we show that Monte Carlo expectation-maximization algorithms are particularly well-suited to estimating this type of model. Third, based on an application of our empirical modeling framework with a sample of French grain crop producers, we demonstrate substantial variability in farmers’ responses to economic incentives. Fourth, we use the estimated model and a simple “statistical calibration” procedure to build farm-specific simulation models, which are then used to evaluate the effects of the rapeseed price increase induced by European Union (EU) biofuel support. Our simulation results demonstrate that ignoring the variability in the considered farmers’ responses to the economic incentives results in significant overestimation of the increases in rapeseed yield levels and variable input use levels induced by EU biofuel support, as well as significant underestimation of the variability in the congruent increases in rapeseed acreages.

Ectoine and hydroxyectoine as typical representatives of compatible solutes are not only essential for extremophiles to survive in extreme environments, but also widely used in cosmetic and medical industries. Ectoine was traditionally produced by Halomonas elongata through a “bacterial milking” process, of which the marked feature is using a high-salt medium to stimulate ectoine biosynthesis and then excreting ectoine into a low-salt medium by osmotic shock. The optimal hydroxyectoine production was achieved by optimizing the fermentation process of Halomonas salina . However, high-salinity broth exacerbates the corrosion to fermenters, and more importantly, brings a big challenge to the subsequent wastewater treatment. Therefore, increasing attention has been paid to reducing the salinity of the fermentation broth but without a sacrifice of ectoine/hydroxyectoine production. With the fast development of functional genomics and synthetic biology, quite a lot of progress on the bioproduction of ectoine/hydroxyectoine has been achieved in recent years. The importation and expression of an ectoine producing pathway in a non-halophilic chassis has so far achieved the highest titer of ectoine (~ 65 g/L), while rational flux-tuning of halophilic chassis represents a promising strategy for the next-generation of ectoine industrial production. However, efficient conversion of ectoine to hydroxyectoine, which could benefit from a clearer understanding of the ectoine hydroxylase, is still a challenge to date.

A companion to the bestseller, The Impact of Economic Policies on Poverty and Income Distribution, this title deals with theoretical challenges and cutting-edge macro-micro linkage models. The authors compare the predictive and analytical power of various macro-micro linkage techniques using the traditional RHG approach as a benchmark to evaluate standard policies, such as, a typical stabilization package and a typical structural reform policy.

Synthetic biology provides powerful tools and novel strategies for designing and modifying microorganisms to function as cell factories for biomanufacturing, which is a promising approach for realizing chemical production in a green and sustainable manner. Recent advances in genetic component design and genome engineering have enabled significant progresses in the field of synthetic biology chassis that have been developed for enzymes or biochemical production based on synthetic biology strategies, with particular reference to model microorganisms, such as Escherichia coli, Bacillus subtilis, Corynebacterium glutamicum, and Saccharomyces cerevisiae. In this review, strategies for engineering four different functional cellular modules which encompass the total process of biomanufacturing are discussed, including expanding the substrate spectrum for substrate uptake modules, refactoring biosynthetic pathways and dynamic regulation for product synthesis modules, balancing energy and redox modules, and cell membrane and cell wall engineering of product storage and secretion modules. Novel strategies of integrating and coordinating different cellular modules aided by synthetic co-culturing of multiple chassis, artificial intelligence–aided data mining for guiding strain development, and the process for designing automatic chassis development via biofoundry are expected to generate next generations of model microorganism chassis for more efficient biomanufacturing.Key points• Engineering of functional cellular modules facilitate next generations of chassis construction.• Global optimization of biosynthesis can be improved by metabolic models.• Data-driven and automatic strain development can improve microorganism chassis construction.