Hydrodynamic modelling of hydrostatic magnesium extrusion

Wilson’s hydrodynamic model of the hydrostatic extrusion process is extended to meet the geometry found on residual billets. The transition from inlet\ud to work zone of the process is not considered sharp as in the model of Wilson but as a rounded edge, modelled by a parabolic function. It is shown that\ud this rounded edge has a considerable influence on the predicted film thickness. Furthermore, it is shown that for hydrostatic extrusion of magnesium with castor oil as pressure medium, it is not possible to generate full film lubrication in the work zone of the hydrostatic extrusion process

MODEX: Laboratory experiment exploring sediment spreading of a mound under waves and currents

The dispersal of sand from submerged mounds in the nearshore is driven by the interplay of processes such as converging and recirculating flows, changing roughness, bed slope effects and wave focusing/refraction. This morphological diffusivity is key to understanding sand bars in shallow seas, tidal inlets, estuaries, and the nearshore response to human interventions such as nourishments and dredging. Most of the work on the evolution of submerged mounds has been based on fluvial studies, focusing on flow without waves. In these cases, circular mounds tend to deform to crescentic (barchan) shapes. In contrast, observations of sandbars and berms in the nearshore subjected to waves show much more complex translation and deformation behavior. This contribution introduces the laboratory MOrphological Diffusivity Experiment (MODEX) aimed at examining morphological diffusivity under different forcing conditions. The experiment particularly addresses the linkages between small scale (local) effects (e.g. bed slope, bedforms) on the adjustment of sandy mounds.Peer ReviewedPostprint (published version

Port: A software tool for digital data donation

Recently, a new workflow has been introduced that allows academic researchers to partner with individuals interested in donating their digital trace data for academic research purposes (Boeschoten, Ausloos, et al., 2022). In this workflow, the digital traces of participants are processed locally on their own devices in such a way that only the subset of participants’ digital trace data that is of legitimate interest to a research project are shared with the researcher, which can only occur after the participant has provided their informed consent.This data donation workflow consists of the following steps: First, the participant requests a digital copy of their personal data at the platform of interest, such as Google, Meta, Twitter and other digital platforms, i.e., their Data Download Package (DDP). Platforms, as data controllers, are required as per the European Union’s General Data Protection Regulation (GDPR) to share a digital copy with each participant requesting such a copy. Second, they download the DDP onto their personal device. Third, by means of local processing, only thedata points of interest to the researcher are extracted from that DDP. Fourth, the participant inspects the extracted data points after which the participant can consent to donate. Only after providing this consent, the donated data is sent to a storage location and can be accessed by the researcher, which would mean that the storage location can be accessed for further analysis.In this paper, we introduce Port. Port is a software tool that allows researchers to configure the local processing step of the data donation workflow, allowing the researcher to collect exactly the digital traces needed to answer their research question. When using Port, a researcher can decide:• Which digital platforms are investigated;• Which digital traces are collected;• How the extracted digital traces are visually presented to the participant;• What is communicated to the participant

Quality and usability of clinical assessments of static standing and sitting posture:A systematic review

BACKGROUND: A validated method to assess sitting and standing posture in a clinical setting is needed to guide diagnosis, treatment and evaluation of these postures. At present, no systematic overview of assessment methods, their clinimetric properties, and usability is available. OBJECTIVE: The objective of this study was to provide such an overview and to interpret the results for clinical practice. METHODS: A systematic literature review was performed according to international guidelines. Two independent reviewers assessed risk of bias, clinimetric values of the assessment methods, and their usability. Quality of evidence and strength of recommendations were determined according to the Grading of Recommendations Assessment, Development and Evaluation working group (GRADE). RESULTS: Out of 27,680 records, 41 eligible studies were included. Thirty-two assessment instruments were identified, clustered into five categories. The methodological quality of 27 (66%) of the articles was moderate to good. Reliability was most frequently studied. Little information was found about validity and none about responsiveness. CONCLUSIONS: Based on a moderate level of evidence, a tentative recommendation can be made to use a direct visual observation method with global posture recorded by a trained observer applying a rating scale

Induction of hyperammonia in irradiated hepatoma cells: a recapitulation and possible explanation of the phenomenon

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Impact of calcium on salivary α-amylase activity, starch paste apparent viscosity and thickness perception

Thickness perception of starch-thickened products during eating has been linked to starch viscosity and salivary amylase activity. Calcium is an essential cofactor for α-amylase and there is anecdotal evidence that adding extra calcium affects amylase activity in processes like mashing of beer. The aims of this paper were to (1) investigate the role of salivary calcium on α-amylase activity and (2) to measure the effect of calcium concentration on apparent viscosity and thickness perception when interacting with salivary α-amylase in starch-based samples. α-Amylase activity in saliva samples from 28 people was assessed using a typical starch pasting cycle (up to 95 °C). The activity of the enzyme (as measured by the change in starch apparent viscosity) was maintained by the presence of calcium, probably by protecting the enzyme from heat denaturation. Enhancement of α-amylase activity by calcium at 37 °C was also observed although to a smaller extent. Sensory analysis showed a general trend of decreased thickness perception in the presence of calcium, but the result was only significant for one pair of samples, suggesting a limited impact of calcium enhanced enzyme activity on perceived thickness

Adipocytes harbor a glucosylceramide biosynthesis pathway involved in iNKT cell activation

Background: Natural killer T (NKT) cells in adipose tissue (AT) contribute to whole body energy homeostasis. Results: Inhibition of the glucosylceramide synthesis in adipocytes impairs iNKT cell activity. Conclusion: Glucosylceramide biosynthesis pathway is important for endogenous lipid antigen activation of iNKT cells in adipocytes.Significance: Unraveling adipocyte-iNKT cell communication may help to fight obesity-induced AT dysfunction.Overproduction and/or accumulation of ceramide and ceramide metabolites, including glucosylceramides, can lead to insulin resistance. However, glucosylceramides also fulfill important physiological functions. They are presented by antigen presenting cells (APC) as endogenous lipid antigens via CD1d to activate a unique lymphocyte subspecies, the CD1d-restricted invariant (i) natural killer T (NKT) cells. Recently, adipocytes have emerged as lipid APC that can activate adipose tissue-resident iNKT cells and thereby contribute to whole body energy homeostasis. Here we investigate the role of the glucosylceramide biosynthesis pathway in the activation of iNKT cells by adipocytes.UDP-glucose ceramide glucosyltransferase (Ugcg), the first rate limiting step in the glucosylceramide biosynthesis pathway, was inhibited via chemical compounds and shRNA knockdown in vivo and in vitro. beta-1,4-Galactosyltransferase (B4Galt) 5 and 6, enzymes that convert glucosylceramides into potentially inactive lactosylceramides, were subjected to shRNA knock down. Subsequently, (pre)adipocyte cell lines were tested in co-culture experiments with iNKT cells (IFN gamma and 114 secretion).Inhibition of Ugcg activity shows that it regulates presentation of a considerable fraction of lipid self-antigens in adipocytes. Furthermore, reduced expression levels of either B4Galt5 or -6, indicate that B4Galt5 is dominant in the production of cellular lactosylceramides, but that inhibition of either enzyme results in increased iNKT cell activation. Additionally, in vivo inhibition of Ugcg by the aminosugar AMP-DNM results in decreased iNKT cell effector function in adipose tissue.Inhibition of endogenous glucosylceramide production results in decreased iNKT cells activity and cytokine production, underscoring the role of this biosynthetic pathway in lipid self-antigen presentation by adipocytes

Adipocytes harbor a glucosylceramide biosynthesis pathway involved in iNKT cell activation

Background: Natural killer T (NKT) cells in adipose tissue (AT) contribute to whole body energy homeostasis. Results: Inhibition of the glucosylceramide synthesis in adipocytes impairs iNKT cell activity. Conclusion: Glucosylceramide biosynthesis pathway is important for endogenous lipid antigen activation of iNKT cells in adipocytes.Significance: Unraveling adipocyte-iNKT cell communication may help to fight obesity-induced AT dysfunction.Overproduction and/or accumulation of ceramide and ceramide metabolites, including glucosylceramides, can lead to insulin resistance. However, glucosylceramides also fulfill important physiological functions. They are presented by antigen presenting cells (APC) as endogenous lipid antigens via CD1d to activate a unique lymphocyte subspecies, the CD1d-restricted invariant (i) natural killer T (NKT) cells. Recently, adipocytes have emerged as lipid APC that can activate adipose tissue-resident iNKT cells and thereby contribute to whole body energy homeostasis. Here we investigate the role of the glucosylceramide biosynthesis pathway in the activation of iNKT cells by adipocytes.UDP-glucose ceramide glucosyltransferase (Ugcg), the first rate limiting step in the glucosylceramide biosynthesis pathway, was inhibited via chemical compounds and shRNA knockdown in vivo and in vitro. beta-1,4-Galactosyltransferase (B4Galt) 5 and 6, enzymes that convert glucosylceramides into potentially inactive lactosylceramides, were subjected to shRNA knock down. Subsequently, (pre)adipocyte cell lines were tested in co-culture experiments with iNKT cells (IFN gamma and 114 secretion).Inhibition of Ugcg activity shows that it regulates presentation of a considerable fraction of lipid self-antigens in adipocytes. Furthermore, reduced expression levels of either B4Galt5 or -6, indicate that B4Galt5 is dominant in the production of cellular lactosylceramides, but that inhibition of either enzyme results in increased iNKT cell activation. Additionally, in vivo inhibition of Ugcg by the aminosugar AMP-DNM results in decreased iNKT cell effector function in adipose tissue.Inhibition of endogenous glucosylceramide production results in decreased iNKT cells activity and cytokine production, underscoring the role of this biosynthetic pathway in lipid self-antigen presentation by adipocytes

Ability and disability in autism spectrum disorder:a systematic literature review employing the International Classification of Functioning, Disability and Health-Children and Youth version

Objective: This study is the first in a series of four empirical investigations to develop International Classification of Functioning, Disability and Health (ICF) Core Sets for Autism Spectrum Disorder (ASD). The objective was to use a systematic review approach to identify, number, and link functional ability and disability concepts used in the scientific ASD literature to the nomenclature of the ICF-CY (Children and Youth version of the ICF, covering the life span). Methods: Systematic searches on outcome studies of ASD were carried out in Medline/PubMed, PsycINFO, ERIC and Cinahl, and relevant functional ability and disability concepts extracted from the included studies. These concepts were then linked to the ICF-CY by two independent researchers using a standardized linking procedure. New concepts were extracted from the studies until saturation of identified ICF-CY categories was reached. Results: Seventy-one studies were included in the final analysis and 2475 meaningful concepts con tained in these studies were linked to 146 ICF-CY categories. Of these, 99 categories were considered most relevant to ASD (i.e., identified in at least 5% of the studies), of which 63 were related to Activities and Participation, 28 were related to Body functions, and 8 were related to Environmental factors. The five most frequently identified categories were basic interpersonal interactions (51%), emotional functions (49%), complex interpersonal interactions (48%), attention functions (44%), and mental functions of language (44%). Conclusion: The broad variety of ICF-CY categories identified in this study reflects the heterogeneity of functional differences found in ASD—both with respect to disability and exceptionality—and underlines the potential value of the ICF-CY as a framework to capture an individual's functioning in all dimensions of life. The current results in combination with three additional preparatory studies (expert survey, focus groups, and clinical study) will provide the scientific basis for defining the ICF Core Sets for ASD for multipurpose use in basic and applied research and every day clinical practice of ASD. Autism Res 2015, 8: 782–794. © 2015 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research