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A key development toward new electronic devices integrating memory and processing capabilities could be based on the electric control of the spin texture of charge carriers in semiconductors. In that respect, GeTe has been recently recognized as a promising ferroelectric Rashba semiconductor, with giant spin splitting of the band structure, due to the inversion symmetry breaking arising from ferroelectric polarization. Here, we address the temperature dependence of the ferroelectric structure of GeTe thin films grown on Si(111). We demonstrate the hysteretic behavior of the ferroelectric domain density upon heating/cooling cycles by low energy electron microscopy. This behavior is associated with an abnormal evolution of the GeTe lattice parameter as shown by x-ray diffraction. We explain these thermomechanical phenomena by a large difference of thermal expansion coefficients between the film and the substrate and to the pinning of the GeTe/Si interface. The accumulated elastic energy by the GeTe thin film during sample cooling is released by the formation of a -nanodomains with in-plane ferroelectric polarization components. [ABSTRACT FROM AUTHOR]

In a thermal gradient, surface nanostructures have been experimentally observed to move due to thermomigration. However, analytical models that describe the thermomigration force acting on surfaces are still controversial. In this work, we start from a thermodynamic approach based on the Massieu function, which is used to describe thermomigration of single adatoms, to develop an expression for the velocity of thermomigrating 2D holes. The model can be simplified in two limiting cases: (i) When the hole motion is limited by adspecies diffusion, the velocity is independent from the hole size (as in our experiments). (ii) If the hole motion is limited by the attachment or detachment of species to or from steps, then the velocity is proportional to the hole width. We have studied the thermomigration of 2D monatomic deep holes on Si(100) using low energy electron microscopy. From the velocity measurements taken at different temperatures, we find, using our model, that the sum of the migration energy and the adatom creation energy is 1.95 ± 0.16 eV. This value is consistent with those found by other authors, reinforcing the validity of our thermomigration model. [ABSTRACT FROM AUTHOR]

We studied the diffusion of 3D nanovoids in a bcc solid by kinetic Monte Carlo simulations. The diffusion coefficient as a function of the void size increases, reaches a maximum, and then decreases. The first increase is particularly interesting, as the diffusion of clusters is generally considered a decreasing function of the cluster size. We attribute this behavior to a curvature-dependent energy barrier for mass transport. We propose an analytical modeling of the void diffusion coefficient that reproduces the simulation data over the whole size range. In addition, for low temperatures and small sizes, the void diffusion coefficient vs size displays valleys, i.e., regions where the diffusion coefficient is smaller than the general trend. This behavior cannot be explained with analytical developments and is due to the formation of compact shapes for certain magic void sizes. In these shapes, the atoms at the void surface are strongly bound, displace less, and thus also void diffusion is slower. [ABSTRACT FROM AUTHOR]

Contemporary views on meat reflect an ambiguous status of appreciation and rejection, especially in the urbanised West, and tend to come with strong moral overtones. The portrayal of (red) meat as an intrinsically harmful food choice by certain academics, non-governmental organisations, mass media, and public-private partnerships contributes to this tension. Although most of these voices are merely calling for a moderation of the consumption of meat in areas with high intake, others are radical and demand a drastic reduction or even elimination, as will be documented in this article. Some scientists are beginning to articulate their concern about an ongoing trend towards unbalanced communications and anti-meat militancy in both academic and policy circles. The perceived threat is not only that the vilification of meat may add to the ongoing moralisation of dietary choices and societal polarisation, but also that it may further undermine an already precarious situation of public health and a fragile food system, especially (but not only) in the Global South. Minimising livestock may also come with unintended harmful effects on ecosystems and livelihoods. The 'Dublin Declaration of Scientists on the Societal Role of Livestock', issued in October 2022, exemplifies such concern. Together with the body of evidence to which it refers, the Dublin Declaration is to be read as a petition for pragmatism, demanding sufficiently high standards of evidence, and more respect for the principle of caution when it comes to policies that have the intention to severely challenge the role of meat and other animal source foods in future diets. There is an ongoing trend towards unbalanced communications and anti-meat militancy in media and academic and policy circles Minimising livestock beyond a critical threshold may come with unintended harmful effects on nutrient security, ecosystems, and livelihoods The 'Dublin Declaration of Scientists on the Societal Role of Livestock' serves as petition for pragmatism, caution, and evidence-based policies [ABSTRACT FROM AUTHOR]

There is considerable scientific debate over the certainty of the evidence associating intake with morbidity and mortality based on what has been provided by many nutritional epidemiologists vis-à-vis the absence of long-term randomized trials of red and processed meat intake and clinical health outcomes. Non-communicable disease risk associated with red and processed meat consumption - magnitude, certainty, and contextuality of risk? Modeled analyses and estimates by [25], [37], and others, are dependent on two key assumptions; 1) that the theoretical minimum risk exposure levels (TMREL) or optimal intakes of red and processed meats are zero; and 2) that risk rises sharply even with moderate consumption of red and processed meats. Keywords: certainty; meat; mortality; noncommunicable diseases; public health; risk EN certainty meat mortality noncommunicable diseases public health risk 19 27 9 04/19/23 20230401 NES 230401 Implications Mean global intakes per person of red and processed meats are 51 and 17 g/day respectively. [Extracted from the article]

Moreover, given that meat represents a high-quality food matrix for digestibility and absorption of a broad spectrum of nutrients, several of which being already limiting factors in diets worldwide, it seems fair to state that the dietary role of meat is not straightforward to replace. Meat science, animal source foods, nutrition, sustainable livestock, economics of protein, ethics of livestock The societal role of meat - what the science says Keywords: animal source foods; meat science; nutrition; sustainable livestock; economics of protein; ethics of livestock EN animal source foods meat science nutrition sustainable livestock economics of protein ethics of livestock 3 8 6 04/19/23 20230401 NES 230401 Eating meat has been the aspiration for an enjoyable and nutritious meal in most cultures and during most times for at least as long as there are written records, and likely far back to the earliest days of our genus some 2 million yr ago. [Extracted from the article]

Contribution of Meat to Global Nutrient Supply Using global food production, loss, and use data, it has been possible to understand how global nutrient supplies from food matches up to global population requirements. Keywords: evolutionary diets; health; micronutrients; nutrition; Paleolithic; protein EN evolutionary diets health micronutrients nutrition Paleolithic protein 11 18 8 04/19/23 20230401 NES 230401 Implications Aspects of human anatomy, digestion, and metabolism diverged from other primates, indicating evolutionary reliance on, and compatibility with, substantial meat intake. The contribution of food groups to the global supply of nutrients and dietary fiber from food, with all forms of meat for human consumption (including organ meat and processed meats) highlighted. Animal-sourced foods, such as meat, are the best source of nutrient-rich foods for children aged 6-23 months (a finding supported by the World Health Organization), leading to compelling benefits on cognitive functions ([4]). [Extracted from the article]

Despite being part of the now often unfavourably perceived category of processed meats, fermented meats remain of substantial nutritional, economic, and cultural importance in today's foodscapes. This translates into a vast assortment of different products. Fermentation is driven by microorganisms (e.g. in fermented sausages), although the terminology is sometimes used to also designate products in which microbial contributions are less dominant and that depend primarily on the activity of endogenous meat enzymes (e.g. in raw hams). A summary is given of the main microbial groups that characterize various types of meat and, in particular, their fermented derivatives. Moreover, it is argued that producers of fermented meat products struggle to adapt to a contemporary dietary context of change. On the one hand, they wish to reassure consumers by reaffirming the position of fermented meat products as traditional strongholds. On the other hand, producers are trying to alleviate some of the perceived concerns through technological innovation, for instance related to the impact of processing on food safety and health. This review raises the point that these sometimes contradictory trends can affect the choice of meat type, ingredients, and processing parameters, and how these choices, in turn, can affect microbial diversity. [ABSTRACT FROM AUTHOR]

Per capita meat consumption in post-industrial countries is higher today than it has been ever since the transition of hunter-gathering to agriculture, while attitudes toward meat production and animal killing have become increasingly characterized by moral ambiguity and disgust. To contribute to our understanding of the genesis of this meat paradox, this study analyses how mid-nineteenth-century Belgian meat retailers constructed the image of their product. Analyzing 54 porcelain cards, uniquely early pictorial business cards used to advertise, shows how they constructed a very specific image of meat and its production process, an image in which meat itself was almost wholly absent. As shifts in the production process removed the animals behind the urban meat supply further and further from urbanites' sight, meat retailers deliberately called upon images of idealized healthy living animals in profoundly natural settings. Reminders of the brutal production process were avoided at all costs. Rather, meat retailers sold the idea of meat consumption as intricately linked to a romanticized pastoral life, where animals lived free from human constraints or instrumentalization. This highly paradoxical "naturalisation" process, cutting out all human intervention in the production of meat, still serves to underpin important cultural aspects of the meat paradox today. [ABSTRACT FROM AUTHOR]