857 research outputs found
Comparing field observations of sorting patterns along tidal sand waves with theoretical predictions
We present a site-by-site comparison between field observations and model predictions of grains size variations over tidal sand waves at six sites in the North Sea. To drive the model, at each location, local sediment characteristics are derived from the described field data, while hydrodynamic conditions are determined from a numerical model for tidal wave propagation in the North Sea. It is found that the theoretical model providesreasonable estimates of the occurring tidally generated bed forms. Moreover, at five of the six locations, the modeldescribes a sorting pattern which concurs with the observed sediment grain size variation, indicating that the model provides a fair description of the processes governing the phenomenon
Reproducibility and validity of a diet quality index for children assessed using a FFQ
The diet quality index (DQI) for preschool children is a new index developed to reflect compliance with four main food-based dietary guidelines for preschool children in Flanders. The present study investigates: (1) the validity of this index by comparing DQI scores for preschool children with nutrient intakes, both of which were derived from 3d estimated diet records; (2) the reproducibility of the DQI for preschoolers based on a parentally reported forty-seven-item FFQ DQI, which was repeated after 5 weeks; (3) the relative validity of the FFQ DQI with 3d record DQI scores as reference. The study sample included 510 and 58 preschoolers (2-5-6.5 years) for validity and reproducibility analyses, respectively. Increasing 3d record DQI scores were associated with decreasing consumption of added sugars, and increasing intakes of fibre, water, Ca and many micronutrients. Mean FFQ DQI test-retest scores were not significantly different: 72 (so 11) v. 71 (Si) 10) (P-=0-218) out of a maximum of 100. Mean 3d record DQI score (66 (so 10)) was significantly lower than mean FFQ DQI (71 (so 10);
A high-affinity antibody against the CSP N-terminal domain lacks Plasmodium falciparum inhibitory activity
Malaria is a global health concern and research efforts are ongoing to develop a superior vaccine to RTS,S/AS01. To guide immunogen design, we seek a comprehensive understanding of the protective humoral response against Plasmodium falciparum circumsporozoite protein (PfCSP). In contrast to the well-studied responses to the repeat region and the C-terminus, the antibody response against the N-terminal domain of PfCSP (N-CSP) remains obscure. Here, we characterized the molecular recognition and functional efficacy of the N-CSP-specific monoclonal antibody 5D5. The crystal structure at 1.85 Åresolution revealed that 5D5 binds an α-helical epitope in N-CSP with high affinity through extensive shape and charge complementarity, and the unusual utilization of an N-linked glycan. Nevertheless, functional studies indicated low 5D5 binding to live Pf sporozoites, and lack of sporozoite inhibition in vitro and in mosquitoes. Overall, our data on low recognition and inhibition of sporozoites do not support the inclusion of the 5D5 epitope into the next generation of CSP-based vaccines.Summary Statement The Plasmodium falciparum sporozoite surface protein, PfCSP, is an attractive vaccine target, but the antibody response against the CSP N-terminal domain has remained understudied. Here, to guide immunogen design, Thai et al. provide insights into the binding motif and functional efficacy of the N-terminal domain-specific monoclonal antibody, 5D5
On the difference between updating the mixing matrix and updating the separation matrix
Raw data for our paper: "Interrelated chemical-microstructural-nanomechanical variations in the structural units of the cuttlebone of Sepia officinalis" DOI: 10.1063/1.499320
Influence of supramolecular forces on the linear viscoelasticity of gluten
Stress relaxation behavior of hydrated gluten networks was investigated by means of rheometry combined with μ-computed tomography (μ-CT) imaging. Stress relaxation behavior was followed over a wide temperature range (0–70 °C). Modulation of intermolecular bonds was achieved with urea or ascorbic acid in an effort to elucidate the presiding intermolecular interactions over gluten network relaxation. Master curves of viscoelasticity were constructed, and relaxation spectra were computed revealing three relaxation regimes for all samples. Relaxation commences with a well-defined short-time regime where Rouse-like modes dominate, followed by a power law region displaying continuous relaxation concluding in a terminal zone. In the latter zone, poroelastic relaxation due to water migration in the nanoporous structure of the network also contributes to the stress relief in the material. Hydrogen bonding between adjacent protein chains was identified as the determinant force that influences the relaxation of the networks. Changes in intermolecular interactions also resulted in changes in microstructure of the material that was also linked to the relaxation behavior of the networks
A model for the compressible, viscoelastic behavior of human amnion addressing tissue variability through a single parameter
A viscoelastic, compressible model is proposed to rationalize the recently reported response of human amnion in multiaxial relaxation and creep experiments. The theory includes two viscoelastic contributions responsible for the short- and long-term time- dependent response of the material. These two contributions can be related to physical processes: water flow through the tissue and dissipative characteristics of the collagen fibers, respectively. An accurate agreement of the model with the mean tension and kinematic response of amnion in uniaxial relaxation tests was achieved. By variation of a single linear factor that accounts for the variability among tissue samples, the model provides very sound predictions not only of the uniaxial relaxation but also of the uniaxial creep and strip-biaxial relaxation behavior of individual samples. This suggests that a wide range of viscoelastic behaviors due to patient-specific variations in tissue composition
Healing Multiculturalism: Middle-Ground Liberal Forgiveness in a Diverse Public Realm
This article examines debates about political forgiveness in liberal, pluralist societies. Although the concept of forgiveness is not usually taken up by liberals, I outline a plausible conception by exploring two recent approaches. The first, ‘unattached articulation’, concept requires no real emotional change on the forgiver’s part, but rather a form of civic restraint. In contrast, the second version highlights a strong form of empathy for perpetrators. In spite of their advantages, each concept proves too extreme. The problems are revealed by focusing on the case of the Harkis, who fought for the French during the Algerian war. Often still marginalised in French society, their case helps to highlight the conceivability of a ‘middle-ground’ or moderate concept of political forgiveness. Its core rests on the forgiver’s care for the social world. While this concept brings considerable challenges also, and is not inevitable in any particular case, it entails a more plausible combination of emotional and rational shifts in the forgiver’s world-view. Although the article does not recommend forgiveness by any person or group, it observes, recalling Arendt’s idea of amor mundi or ‘love of the world’, that political forgiveness may sustain a viable connection between diverse citizens’ public and non-public lives
Historicising Material Agency: from Relations to Relational Constellations
Relational approaches have gradually been changing the face of archaeology over the last decade: analytically, through formal network analysis; and interpretively, with various frameworks of human-thing relations. Their popularity has been such, however, that it threatens to undermine their relevance. If everyone agrees that we should understand past worlds by tracing relations, then ‘finding relations’ in the past becomes a self-fulfilling prophecy. Focusing primarily on the interpretive approaches of material culture studies, this article proposes to counter the threat of irrelevance by not just tracing human-thing relations, but characterising how sets of relations were ordered. Such ordered sets are termed ‘relational constellations’. The article describes three relational constellations and their consequences based on practices of fine ware production in the Western Roman provinces (first century BC – third century AD): the fluid, the categorical, and the rooted constellation. Specifying relational constellations allows reconnecting material culture to specific historical trajectories, and offers scope for meaningful cross-cultural comparisons. As such a small theoretical addition based on the existing toolbox of practice-based approaches and relational thought can impact on historical narratives, and can save relational frameworks from the danger of triviality.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s10816-015-9244-
Supply Chain Disruption Costs Study in International Containerised Maritime Transportation
The global economy relies highly on international trade, and the international maritime transport system acts as the lifeblood carrying and transporting materials and goods globally, realizing the economy globalization in an effective and efficient way. However, globalization increases the interdependence and complexity of global supply chains and drives it to be more vulnerable to disruptions. Meanwhile, the international marine transport system is a complex and intertwined system exposed to high risks and decreased safety due to its very accessibility and operational flexibility. Thereby, global supply chains integrated with international maritime transportation systems are inherently vulnerable to various disruptions. Studies of supply chain disruptions particularly quantifying transport related disruption costs are becoming increasingly important. However, research on maritime transport related supply chain disruptions, in particular, quantifying its disruption costs is under-represented in the transport literature, due largely to the features of supply chain disruptions, but also because of the complexity of maritime related supply chains. Current research in transportation has tended to concentrate on shippers’ transport mode choice and port selection. In the context of a global market, however, the behaviour of maritime containerised shippers has to be viewed as a complex decision and an integral element of the supply chain management strategy. Those shippers’ transportation choice decisions should be emphasized and studied to reveal their behaviour changes between normal operations and disruption circumstance. This research adds to the paucity work on investigating the maritime transport related supply chain disruptions and quantifying its disruption costs based on shippers’ maritime transportation choice behaviour. It presents the results of a microanalysis of freight transport choice decisions in an international containerised maritime transport chain context. The Latent Class Model (LCM) is applied to identify the key service attributes and its preference heterogeneity in maritime transportation and to estimate the marginal values for the quality of maritime transport service with and without a disruption, simultaneously, quantifying the disruption costs through comparing each attribute’s marginal value difference between normal and disruption operations. The Seemingly Unrelated Regression model (SURE) is utilized to explore the sources influencing shippers’ preference heterogeneities. In doing so, we are able to gain an understanding as to where and how much should be invested in order to facilitate recovery in the case of a disruption based on the view of the maritime participants’ perspectives. The research results confirm freight rate, transit time, reliability, damage rate, and frequency as the key service attributes influencing shippers’ transport choice. They also reveal shippers’ VOT increase by more than four-times, VOR nearly double, and VOD increase about twenty percent if a disruption takes place, and identify shippers’ transport decisions vary with its product, shipment, company and supply chain characteristics no matter with or without a disruption. This research quantifies the costs of supply chain disruption in containerised maritime transport context for the first time, and its results provide useful industrial implications for maritime transport chain related parties
Three-dimensional modeling of human placental terminal villi.
INTRODUCTION: Placental transport is the main factor affecting the health and development of the fetus. Due to the placenta's geometrical and mathematical complexity, the structure-function relations of placental terminal villi have not been successfully modeled. Hence, a novel modeling approach is proposed. METHODS: Computational models of four different specimens were generated from the three-dimensional reconstruction of confocal laser scanning microscopic image stacks. To evaluate the capabilities of the proposed methodology, stationary oxygen diffusion transport was calculated in the terminal villus volumes. RESULTS: The reconstructions automatically provided the spatial arrangement of the fetal capillaries inside the terminal villi. The surface and volume ratios between the fetal capillaries and the villus were also calculated, and the effects of model parameters on the placental diffusive capacity were assessed by parametric analysis. DISCUSSION: The potential of three-dimensional reconstructions combined with finite element analysis as a research tool for the human placenta was tested. The methodology herein could serve in the future as a simulation platform for complicated in vivo and in vitro scenarios.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.placenta.2016.05.00
- …
