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Strontium substitution of gelatin modified calcium hydrogen phosphates as porous hard tissue substitutes
Aiming at the generation of a high strontium-containing degradable bone substitute, the exchange of calcium with strontium in gelatin-modified brushite was investigated. The ion substitution showed two mineral groups, the high-calcium containing minerals with a maximum measured molar Ca/Sr ratio of 80%/20% (mass ratio 63%/37%) and the high-strontium containing ones with a maximum measured molar Ca/Sr ratio of 21%/79% (mass ratio 10%/90%). In contrast to the high-strontium mineral phases, a high mass loss was observed for the calcium-based minerals during incubation in cell culture medium (alpha-MEM), but also an increase in strength owing to dissolution and re-precipitation. This resulted for the former in a decrease of cation concentration (Ca + Sr) in the medium, while the pH value decreased and the phosphate ion concentration rose significantly. The latter group of materials, the high-strontium containing ones, showed only a moderate change in mass and a decrease in strength, but the Ca + Sr concentration remained permanently above the initial calcium concentration in the medium. This might be advantageous for a future planned application by supporting bone regeneration on the cellular level. © 2020 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals LLC
Patients with fibromyalgia display less functional connectivity in the brain’s pain inhibitory network
Background: There is evidence for augmented processing of pain and impaired endogenous pain inhibition in Fibromyalgia syndrome (FM). In order to fully understand the mechanisms involved in FM pathology, there is a need for closer investigation of endogenous pain modulation. In the present study, we compared the functional connectivity of the descending pain inhibitory network in age-matched FM patients and healthy controls (HC). We performed functional magnetic resonance imaging (fMRI) in 42 subjects; 14 healthy and 28 age-matched FM patients (2 patients per HC), during randomly presented, subjectively calibrated pressure pain stimuli. A seed-based functional connectivity analysis of brain activity was performed. The seed coordinates were based on the findings from our previous study, comparing the fMRI signal during calibrated pressure pain in FM and HC: the rostral anterior cingulate cortex (rACC) and thalamus. Results: FM patients required significantly less pressure (kPa) to reach calibrated pain at 50 mm on a 0–100 visual analogue scale (p < .001, two-tailed). During fMRI scanning, the rACC displayed significantly higher connectivity to the amygdala, hippocampus, and brainstem in healthy controls, compared to FM patients. There were no regions where FM patients showed higher rACC connectivity. Thalamus showed significantly higher connectivity to the orbitofrontal cortex in healthy controls but no regions showed higher thalamic connectivity in FM patients. Conclusion: Patients with FM displayed less connectivity within the brain’s pain inhibitory network during calibrated pressure pain, compared to healthy controls. The present study provides brain-imaging evidence on how brain regions involved in homeostatic control of pain are less connected in FM patients. It is possible that the dysfunction of the descending pain modulatory network plays an important role in maintenance of FM pain and our results may translate into clinical implications by using the functional connectivity of the pain modulatory network as an objective measure of pain dysregulation
Data sharing in neuroimaging research
Significant resources around the world have been invested in neuroimaging studies of brain function and disease. Easier access to this large body of work should have profound impact on research in cognitive neuroscience and psychiatry, leading to advances in the diagnosis and treatment of psychiatric and neurological disease. A trend toward increased sharing of neuroimaging data has emerged in recent years. Nevertheless, a number of barriers continue to impede momentum. Many researchers and institutions remain uncertain about how to share data or lack the tools and expertise to participate in data sharing. The use of electronic data capture (EDC) methods for neuroimaging greatly simplifies the task of data collection and has the potential to help standardize many aspects of data sharing. We review here the motivations for sharing neuroimaging data, the current data sharing landscape, and the sociological or technical barriers that still need to be addressed. The INCF Task Force on Neuroimaging Datasharing, in conjunction with several collaborative groups around the world, has started work on several tools to ease and eventually automate the practice of data sharing. It is hoped that such tools will allow researchers to easily share raw, processed, and derived neuroimaging data, with appropriate metadata and provenance records, and will improve the reproducibility of neuroimaging studies. By providing seamless integration of data sharing and analysis tools within a commodity research environment, the Task Force seeks to identify and minimize barriers to data sharing in the field of neuroimaging
Spotlights Lehre. Transferpaket zur Verzahnung und Vernetzung von Fachwissenschaft und Fachdidaktik.
Die vorliegende Publikation versteht sich als Ideengeber für die universitäre Lehre in der Lehrerbildung in Gestalt eines sogenannten Transferpakets. Sie berichtet über Ergebnisse des Teilprojekts ‚Spotlights-Lehre‘ des Projekts ‚Schnittstellen gestalten – Lehrerbildung entlang des Leitbildes des "Reflective Practitioner" an der Universität Bremen' im BMBF-Programm ‚Qualitätsoffensive Lehrerbildung‘. Inhaltlich geht es um innovative Lehrprojekte zur Verzahnung und Vernetzung von Fachwissenschaft und Fachdidaktik, die das Ziel verfolgen, Fragmentierungserfahrungen von Lehramtsstudierenden in den Fächern Mathematik, Englisch, Romanistik, Geschichte und Inklusive Didaktik zu reduzieren. Zentrales Anliegen dieses Transferpakets ist es, Transferstrategien bereitzustellen, an Beispielen zu illustrieren und in Lehrbeschreibungen einzubetten. Umfassend wird gezeigt, wie die Designprozesse zur Lehre in den beiden zentralen Modellprojekten der Fächer Englisch und Mathematik gestaltet sowie die Transfer- und Vernetzungsstrategien gewonnen wurden
HIV-Studien und HIV-Projekte am Robert Koch-Institut
Neben der gesetzlich geregelten Surveillance von HIV-Neudiagnosen in Deutschland erfolgt am RKI auch die Durchführung verschiedener Studienprojekte, die im Epidemiologischen Bulletin 49/2019 vorgestellt werden. Das Rückgrat der erweiterten HIV-Surveillance in Deutschland bilden vier Studien: das Monitoring rezenter HIV-Infektionen in Deutschland (InzSurv-HIV), die Molekulare Surveillance von HIV-Neudiagnosen (MolSurv-HIV), die HIV-1 Serokonverterstudie und die Klinische Surveillance der HIV-Erkrankung (ClinSurv-HIV). Bei InzSurv-HIV und MolSurv-HIV werden Proben von Patienten untersucht, die gerade neu diagnostiziert wurden. Bei der HIV-1 Serokonverterstudie und bei ClinSurv-HIV handelt es sich um Kohortenstudien. Ergänzend dazu wird am RKI auch das AIDS-Fallregister betrieben, in dem seit 1982 auf freiwilliger Basis anonym durch die behandelnden Ärzte berichtete AIDS-Erkrankungsfälle und -Todesfälle in Deutschland zusammengetragen und ausgewertet werden
A European threshold value and assessment method for macro litter on coastlines: Guidance developed within the Common Implementation Strategy for the Marine Strategy Framework Directive
The Marine Strategy Framework Directive (MSFD, 2008/56/EC) requires that European threshold values (TVs) for marine litter (descriptor 10) be defined. The MSFD Technical Group on Marine Litter (TG ML) decided to focus on coastline litter (Criterion 1), often referred to as beach litter, in a first step, since for this criterion a monitoring framework is in place and a substantial amount of fit-for-purpose beach litter monitoring data is available at the European scale (see Hanke et al., 2019).
This report describes the rationale and method to obtain a European TV for beach litter, as developed by Member States and other experts within the TG ML.
It was concluded by TG ML that a TV cannot be based on quantitative ecological and socio-economic harm due to a lack of scientific data on harm caused by marine litter on beaches. Of the remaining options, the use of the 10th percentile value of the total litter abundance dataset from all European beaches in the baseline period 2015-2016 was selected and applied, as it was considered to be sufficiently precautionary while being based on already available beach litter abundances in the EU. The underlying baseline dataset was developed within the TG ML.
Calculation of the 10th percentile of the EU baseline dataset resulted in a value of 13 litter items per 100 m of coastline length. Further consideration of the 95% confidence intervals of the TV and assessment value, respectively, led to a final TV of 20 litter items/100 m beach length, which corresponds to the 15th percentile value of the EU baseline dataset. This TV is estimated by experts from TG ML to reduce harm from beach litter to a sufficiently precautionary level. The methodology acknowledges uncertainties in the underlying data which is considered in the proposal. The median assessment value is compared with this TV for compliance checking.
It is acknowledged that achieving this TV will require substantial and sustained measures over a longer period. Intermediate targets over time towards the proposed TV are proposed to support the achievement of the TV.JRC.D.2-Water and Marine Resource
The twilight of the Liberal Social Contract? On the Reception of Rawlsian Political Liberalism
This chapter discusses the Rawlsian project of public reason, or public justification-based 'political' liberalism, and its reception. After a brief philosophical rather than philological reconstruction of the project, the chapter revolves around a distinction between idealist and realist responses to it. Focusing on political liberalism’s critical reception illuminates an overarching question: was Rawls’s revival of a contractualist approach to liberal legitimacy a fruitful move for liberalism and/or the social contract tradition? The last section contains a largely negative answer to that question. Nonetheless the chapter's conclusion shows that the research programme of political liberalism provided and continues to provide illuminating insights into the limitations of liberal contractualism, especially under conditions of persistent and radical diversity. The programme is, however, less receptive to challenges to do with the relative decline of the power of modern states
Probabilistic classification of anti-SARS-CoV-2 antibody responses improves seroprevalence estimates.
OBJECTIVES: Population-level measures of seropositivity are critical for understanding the epidemiology of an emerging pathogen, yet most antibody tests apply a strict cutoff for seropositivity that is not learnt in a data-driven manner, leading to uncertainty when classifying low-titer responses. To improve upon this, we evaluated cutoff-independent methods for their ability to assign likelihood of SARS-CoV-2 seropositivity to individual samples. METHODS: Using robust ELISAs based on SARS-CoV-2 spike (S) and the receptor-binding domain (RBD), we profiled antibody responses in a group of SARS-CoV-2 PCR+ individuals (n = 138). Using these data, we trained probabilistic learners to assign likelihood of seropositivity to test samples of unknown serostatus (n = 5100), identifying a support vector machines-linear discriminant analysis learner (SVM-LDA) suited for this purpose. RESULTS: In the training data from confirmed ancestral SARS-CoV-2 infections, 99% of participants had detectable anti-S and -RBD IgG in the circulation, with titers differing > 1000-fold between persons. In data of otherwise healthy individuals, 7.2% (n = 367) of samples were of uncertain serostatus, with values in the range of 3-6SD from the mean of pre-pandemic negative controls (n = 595). In contrast, SVM-LDA classified 6.4% (n = 328) of test samples as having a high likelihood (> 99% chance) of past infection, 4.5% (n = 230) to have a 50-99% likelihood, and 4.0% (n = 203) to have a 10-49% likelihood. As different probabilistic approaches were more consistent with each other than conventional SD-based methods, such tools allow for more statistically-sound seropositivity estimates in large cohorts. CONCLUSION: Probabilistic antibody testing frameworks can improve seropositivity estimates in populations with large titer variability
Migraine in women: the role of hormones and their impact on vascular diseases
Migraine is a predominantly female disorder. Menarche, menstruation, pregnancy, and menopause, and also the use of hormonal contraceptives and hormone replacement treatment may influence migraine occurrence. Migraine usually starts after menarche, occurs more frequently in the days just before or during menstruation, and ameliorates during pregnancy and menopause. Those variations are mediated by fluctuation of estrogen levels through their influence on cellular excitability or cerebral vasculature. Moreover, administration of exogenous hormones may cause worsening of migraine as may expose migrainous women to an increased risk of vascular disease. In fact, migraine with aura represents a risk factor for stroke, cardiac disease, and vascular mortality. Studies have shown that administration of combined oral contraceptives to migraineurs may further increase the risk for ischemic stroke. Consequently, in women suffering from migraine with aura caution should be deserved when prescribing combined oral contraceptives
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