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Whether Kant’s late legal theory and his theory of race are contradictory in their account of colonialism has been a much-debated question that is also of highest importance for the evaluation of the Enlightenment’s contribution to Europe’s colonial expansion and the dispossession and enslavement of native and black peoples. This article discusses the problem by introducing the discourse on barbarism. This neglected discourse is the original and traditional European colonial vocabulary and served the justification of colonialism from ancient Greece throughout the Renaissance to the eighteenth century. Kant’s explicit rejection of this discourse and its prejudices reveals his early critical stance toward colonial judgements of native peoples even before he developed his legal theory. This development of his critical position can be traced in his writings on race: although he makes racist statements in these texts, his theory of race is not meant to ground moral judgements on ‘races’ or a racial hierarchy but to defend the unity of mankind under the given empirical reality of colonial hierarchies.
Functional and mechanical properties of modern devices are directly controlled by the stress and strain state acting on the materials within. For manufacturers, elastic strain engineering of complex materials systems throughout processing and utilization is crucial. This requires methodologies with ever-increasing spatial and temporal resolutions. On the other hand, the nanoscale elastic strain field around individual defects fundamentally controls the deformation of crystalline materials. To date, a variety of techniques are available for measuring elastic strain, including transmission electron microscopy, electron backscatter diffraction, and x-ray diffraction. Recent advances in instrumentation have dramatically improved speed and resolution, enabling direct elastic strain mapping during in situ deformation at the nanoscale. In addition, plastic strain can be determined during deformation using digital image correlation. Current techniques are surveyed here to accurately quantify complex strain fields at the nanoscale and their potential to resolve scientific challenges in materials science.
Energy-dispersive X-ray techniques can be employed in two different ways for the accurate determination of element concentrations in specimens: (1) spectrometry of fluoresced characteristic X-rays as widely applied in the various modes of the traditional XRF analysis technique, and (2) spectrometry of the energy-differential transmittance of an X-ray continuum at the element-specific absorption-edge energies.
Biofilms are colonies of microorganisms, usually growing on solid-liquid interfaces, consisting of cells and a matrix of extracellular polymeric substances (EPS). Such colonies are often elaborately structured and highly dynamic, expanding through cell division and recruitment of cells from outside, and contracting via individual cells or flocs (groups of cells and biofilm matrix) detachment from the biofilm surface. Even amongst simplest single species bacterial biofilms, the behaviour (phenotype) of individual cells is highly heterogenous across the biofilm due to microenvironment variation (e.g. nutrient concentration, pH) and cell-cell signalling (quorum sensing); consequently, many researchers consider biofilms as more akin to multi-cellular organisms rather than a colony of autonomous individual cells.
We propose a numerical method for the simulation of a quasi-linear parabolic biofilm model that exhibits three non-linear diffusion effects: (i) a power law degeneracy, (ii) a super diffusion singularity and (iii) non-linear cross-diffusion. The method is based on a spatial Finite Volume discretisation in which cross-diffusion terms are formally treated as convection terms. Time-integration of the resulting semi-discretised system is carried out using an error-controlled, time-adaptive, embedded Rosenbrock–Wanner method. We compare several variants of the method and two variants of the model to investigate how details such as the choice cross-diffusion coefficients, and specific variants of the time integrator affect simulation time.
We derive a macroscopic model for biofilm formation in a porous medium reactor to investigate the role of suspended bacteria on reactor performance. The starting point is the mesoscopic one-dimensional Wanner–Gujer biofilm model. The following processes are included: hydrodynamics and transport of substrate in the reactor, biofilm and suspended bacteria growth in the pore space, attachment of suspended cells to the biofilm, and detachment of biofilm cells. The mesoscopic equations are up-scaled from the biofilm scale to the reactor scale, yielding a stiff system of balance laws, which we study numerically. We find that suspended bacteria and attachment can have a significant effect on biofilm reactor performance.
National Health Technology Assessments (HTAs) for medical devices are crucial to regulate the quality and costs of healthcare systems. However, there is diversity in several aspects among European countries. Consequently, controversial results might arise, generating contrary reimbursement decisions. The European Network for Health Technology Assessment (EUnetHTA) is an interface platform for the harmonization of HTA information across Europe. The European Commission expects national uptake of a European HTA. Thus, European HTAs might overcome the diversity of national HTA requirements.
We aimed to compare German and European HTAs for medical devices regarding processes, methods, timelines, and involvement of medical device companies. Therefore we analyzed guidelines, requirements, and output of EUnetHTA and compared those aspects with the German G-BA (Federal Joint Committee, Gemeinsamer Bundesausschuss) standard and IQWiG (Institute for Quality and Efficiency in Health Care, Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen) methods.
We found differences between the European and German HTAs for medical devices regarding timelines, involvement of medical device companies, body of evidence, use of surrogate endpoints, and methodology. European HTAs for medical devices reflect the clinical reality by integrating the existing evidence (including real world data) and by using comprehensive statistical methods for medical devices. In contrast, German HTAs for medical device-based technologies are long lasting and are often restricted to a small body of evidence.
As a conclusion, similar to pharmaceuticals, the European HTA framework might also become a worldwide platform for HTAs of medical device-based technologies with the potential to harmonize reimbursement decisions and patients health care across countries on the basis of clinical reality.
Health Technology Assessment (HTA) processes have become a fundamental part in the lifecycle of new medicines. However, their deep relation with national legislation creates ambiguous and controversial results between the European countries. Can they be standardized across Europe?
Sources of national differences have been identified in timelines, documents, methods, data interpretation, and conclusions. In order to harmonize and standardize HTA cooperation across Europe the European Network for HTA (EUnetHTA) was established. We analyzed guidelines, requirements, and output of EUnetHTA and noted the differences between those guidelines and the German G-BA (Federal Joint Committee, Gemeinsamer Bundesausschuss) standard and IQWiG (Institute for Quality and Efficiency in Health Care, Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen) methods.
The comparison between German and European HTAs highlights that although both procedures follow the rules of Evidence-Based Medicine, differences in Body of Evidence, Comparator, Surrogate Endpoints, Subgroups, and Evidence Synthesis may lead to diverging HTA outcomes. The European HTA framework facilitates the appropriate depiction of clinical reality through comprehensive inclusion of the existing evidence with context specific statistical methods. It might become a worldwide platform for HTA evaluation and discussion.
Only the involvement of both, pharmaceutical companies and HTA bodies within a unified European framework can lead to a mature and transparent procedure with a reliable outcome independent of legal requirements.
This paper revises current understandings of the rôle of land in the economy of the Italian diaspora in the Greek East in the second and first centuries b.c., arguing that these Italians owned more land than has previously been assumed and that many of these Italian landowners practised a highly commercialized form of agriculture that focused on high-end products. This strategy shaped what empire meant both locally and in Italy and Rome, where the products they marketed fed into the ongoing consumer revolutions of the time. After discussing the evidence for the extent of Italian landholdings and examining their exploitation in three case studies, we conclude by reflecting on the long-term history of such landholdings in the provinces and the implications for our understanding of Roman imperialism more generally.
Based on the Developmental Origin of Health and Disease concept, maternal undernutrition has been shown to sensitize adult offspring to metabolic pathologies such as obesity. Using a model of maternal 70% food restriction in pregnant female rats throughout gestation (called FR30), we previously reported that obesity-prone adult male rat offspring displayed hyperleptinemia with modifications in leptin and leptin receptor messenger RNA (mRNA) levels in white adipose tissue (WAT). Apelin is a member of the adipokine family that regulates various aspects of energy metabolism and WAT functionality. We investigated whether apelin and its receptor APJ could be a target of maternal undernutrition. Adult male rat offspring from FR30 dams showed increased plasma apelin levels and apelin gene expression in WAT. Post-weaning high-fat diet led to marked increase in APJ mRNA and protein levels in offspring’s WAT. We demonstrate that maternal undernutrition and post-weaning diet have long-term consequences on the apelinergic system of adult male rat offspring.
Recent developments in a number of fields call for high-throughput, high-resolution imaging of large areas. Examples are reconstruction of macroscopic volumes of mouse brain tissue, or wafer defect inspection. To address these needs, we have developed a multi-beam, single column SEM which utilizes an array of 61 or 91 electron beams and detectors in parallel. The total possible detection speed of the multiple beam SEM is the single detection speed times the number of beams. In the same time a single beam SEM creates an image of several million pixels size, the multi-beam SEM produces between several hundred million and one billion pixels. Herein we demonstrate the capabilities of generating massive data sets using the multi-beam SEM on a variety of samples including brain tissue serial sections and semiconductor test wafers.
As a relatively new class of hierarchically structured materials, nanotwinned (NT) metals exhibit an exceptional combination of high strength, good ductility, large fracture toughness, remarkable fatigue resistance, and creep stability. This article reviews current studies on fracture, fatigue, and creep of NT metals, with an emphasis on the fundamental deformation and failure mechanisms. We focus on the complex interactions among cracks, dislocations, and twin boundaries, the influence of microstructure, twin size, and twinning/detwinning on damage evolution, and the contribution of nanoscale twins to fatigue and creep under indentation and irradiation conditions. The article also includes critical discussions on the effects of twin thickness and grain size on the fracture toughness, fatigue resistance, and creep stability of NT metals.
We apply the immersed boundary (or IB) method to simulate deformation and detachment of a periodic array of wall-bounded biofilm colonies in response to a linear shear flow. The biofilm material is represented as a network of Hookean springs that are placed along the edges of a triangulation of the biofilm region. The interfacial shear stress, lift and drag forces acting on the biofilm colony are computed by using fluid stress jump method developed by Williams, Fauci and Gaver [Disc. Con-tin. Dyn. Sys. B 11(2):519–540, 2009], with a modified version of their exclusion filter. Our detachment criterion is based on the novel concept of an averaged equivalent continuum stress tensor defined at each IB point in the biofilm which is then used to determine a corresponding von Mises yield stress; wherever this yield stress exceeds a given critical threshold the connections to that node are severed, thereby signalling the onset of a detachment event. In order to capture the deformation and detachment behaviour of a biofilm colony at different stages of growth, we consider a family of four biofilm shapes with varying aspect ratio. For each aspect ratio, we varied the spacing between colonies to investigate role of spatial clustering in offering protection against detachment. Our numerical simulations focus on the behaviour of weak biofilms (with relatively low yield stress threshold) and investigate features of the fluid-structure interaction such as locations of maximum shear and increased drag. The most important conclusions of this work are: (a) reducing the spacing between colonies reduces drag by from 50 to 100% and alters the interfacial shear stress profile, suggesting that even weak biofilms may be able to grow into tall structures because of the protection they gain from spatial proximity with other colonies; (b) the commonly employed detachment strategy in biofilm models based only on interfacial shear stress can lead to incorrect or inaccurate results when applied to the study of shear induced detachment of weak biofilms. Our detachment strategy based on equivalent continuum stresses provides a unified and consistent IB framework that handles both sloughing and erosion modes of biofilm detachment, and is consistent with strategies employed in many other continuum based biofilm models.
Somewhere near the heart of much recent liberal political theory is the claim that if the state restricts an agent's liberty, its restrictions should have some rationale that is defensible to each of those whose liberty is constrained. Liberals are committed to “the requirement that all aspects of the social should either be made acceptable or be capable of being made acceptable to every last individual.” In a pluralistic culture, there are many claims which are particularly controversial, many about which we expect “reasonable disagreement.” If we are to enjoy consensus regarding state restrictions, citizens should not support coercive policies on such controversial grounds. If, for example, some coercive policy is passed by popular referendum, and if its supporters have no reason to vote for the policy other than their religious convictions, then, given that reasonable, informed people reject religious belief, the policy in question lacks public justification. Given the liberal view that coercive policies should be defensible to all those affected by them, conscientious citizens should restrain themselves from supporting (or rejecting) policies on the basis of excessively controversial grounds. Principles of restraint specify both the types of grounds on the basis of which citizens may appropriately support a given policy and the types of grounds on which citizens may not properly rely.