Mediamusic (E-Journal)
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Human–environment interactions at a short-lived Arctic mine and the long-term response of the local tundra vegetation
No full textArctic mining has a bad reputation because the extractive industry is often responsible for a suite of environmental problems. Yet, few studies explore the gap between untouched tundra and messy megaproject from a historical perspective. Our paper focuses on Advent City as a case study of the emergence of coal mining in Svalbard (Norway) coupled with the onset of mining-related environmental change. After short but intensive human activity (1904–1908), the ecosystem had a century to respond, and we observe a lasting impact on the flora in particular. With interdisciplinary contributions from historical archaeology, archaeozoology, archaeobotany and botany, supplemented by stable isotope analysis, we examine 1) which human activities initially asserted pressure on the Arctic environment, 2) whether the miners at Advent City were “eco-conscious,” for example whether they showed concern for the environment and 3) how the local ecosystem reacted after mine closure and site abandonment. Among the remains of typical mining infrastructure, we prioritised localities that revealed the subtleties of long-term anthropogenic impact. Significant pressure resulted from landscape modifications, the import of non-native animals and plants, hunting and fowling, and the indiscriminate disposal of waste material. Where it was possible to identify individual inhabitants, these shared an economic attitude of waste not, want not, but they did not hold the environment in high regard. Ground clearances, animal dung and waste dumps continue to have an effect after a hundred years. The anthropogenic interference with the fell field led to habitat creation, especially for vascular plants. The vegetation cover and biodiversity were high, but we recorded no exotic or threatened plant species. Impacted localities generally showed a reduction of the natural patchiness of plant communities, and highly eutrophic conditions were unsuitable for liverworts and lichens. Supplementary isotopic analysis of animal bones added data to the marine reservoir offset in Svalbard underlining the far-reaching potential of our multi-proxy approach. We conclude that although damaging human–environment interactions formerly took place at Advent City, these were limited and primarily left the visual impact of the ruins. The fell field is such a dynamic area that the subtle anthropogenic effects on the local tundra may soon be lost. The fauna and flora may not recover to what they were before the miners arrived, but they will continue to respond to new post-industrial circumstances
The baryonic specific angular momentum of disc galaxies
No full textAims. Specific angular momentum (the angular momentum per unit mass, j = J/M) is one of the key parameters that control the evolution of galaxies, and it is closely related with the coupling between dark and visible matter. In this work, we aim to derive the baryonic (stars plus atomic gas) specific angular momentum of disc galaxies and study its relation with the dark matter specific angular momentum.Methods. Using a combination of high-quality H I rotation curves, H I surface densities, and near-infrared surface brightness profiles, we homogeneously measure the stellar (j*) and gas (jgas) specific angular momenta for a large sample of nearby disc galaxies. This allows us to determine the baryonic specific angular momentum (jbar) with high accuracy and across a very wide range of masses.Results. We confirm that the j* − M* relation is an unbroken power-law from 7 ≲ log(M*/M⊙) ≲ 11.5, with a slope 0.54 ± 0.02, setting a stronger constraint at dwarf galaxy scales than previous determinations. Concerning the gas component, we find that the jgas − Mgas relation is also an unbroken power-law from 6 ≲ log(Mgas/M⊙) ≲ 11, with a steeper slope of 1.02 ± 0.04. Regarding the baryonic relation, our data support a correlation characterized by a single power-law with a slope 0.60 ± 0.02. Our analysis shows that our most massive spirals and smallest dwarfs lie along the same jbar − Mbar sequence. While the relations are tight and unbroken, we find internal correlations inside them: At fixed M*, galaxies with larger j* have larger disc scale lengths, and at fixed Mbar, gas-poor galaxies have lower jbar than expected. We estimate the retained fraction of baryonic specific angular momentum, fj, bar, finding it constant across our entire mass range with a value of ∼0.6, indicating that the baryonic specific angular momentum of present-day disc galaxies is comparable to the initial specific angular momentum of their dark matter haloes. In general, these results set important constraints for hydrodynamical simulations and semi-analytical models that aim to reproduce galaxies with realistic specific angular momenta
In vitro assessment of tick-borne encephalitis vaccine:Suitable human cell platforms and potential biomarkers
No full textTick-borne encephalitis (TBE) virus causes a severe disease that can lead to permanent neurological complications. The whole inactivated TBE vaccine is highly effective, as proven by high seroconversion rates and near eradication of the disease in countries where vaccination programs have been implemented. TBE vaccine potency testing currently requires the use of in vivo methods that present issues of reproducibility as well as animal discomfort. As an alternative, public and private entities are currently exploring a batch-to-batch consistency approach which would demonstrate conformity of a newly produced vaccine batch with a batch with proven in vivo efficacy with respect to a range of in vitro measurable quality parameters. For the identification of a suitable cellular platform to be used in a panel of in vitro batch-to-batch assessments for the TBE vaccine, we exposed human cell-based systems, both of primary origin and cell line-derived, to vaccine formulations of high and low quality. Following stimulation, cell responses were evaluated by assessing the expression of selected genes by qPCR. Our findings show that the expression of interferon-stimulated genes differed after treatment with non-adjuvanted vaccine batches of different quality in peripheral blood mononuclear cells (PBMCs) and in monocyte-derived dendritic cells, but not in monocyte-free PBMC suspensions nor in cell line-derived immune cells. These results indicate suitable platforms and potential biomarkers for a cell-based assay that, together with other immunochemical analyses, could serve for batch-to-batch assessment of the TBE vaccine, reducing (and eventually replacing) in vivo methods for potency testing.</p
What makes a nurse today?:A debate on the nursing professional identity and its need for change
No full textIn 2020, due to the Nightingale year and COVID-19 crisis, nursing is in the public eye more than ever. Nurses often are being seen as compassionate helpers. The public image of nursing, however, also consists of stereotypes such as nursing being a 'doing' profession and care being a 'female' characteristic. Next to that, nursing is associated with images from the past, such as 'the lady with the lamp'. Therefore, in the public eye at least, the nursing identity seems a simple and straightforward enough construct, but nothing less is true. Looking at what a professional identity consists of, historic and social developments influence a group identity as a construct. In addition, individual, professional and contemporary societal moralities, including stereotypes, play its role. Nurses themselves reinforce stereotypes in order to fit into what is expected, even when they believe professional behaviour encompasses other features. They may do so individually as well as in a group context. But nursing actually seems to be better off when viewed upon as a diverse, autonomous profession. Moral values such as compassion motivate nurses to enter the profession. Research shows that if such values are addressed in daily practice, nursing could perhaps be saved from nurses leaving the profession because of feeling unfulfilled. Another aspect concerns the huge nursing body of knowledge. If seen as the ground on which nursing behaviour is standing, it would contribute to a different image of nursing than simplified stereotypes, which do not acknowledge the complex nature of the profession. This paper challenges the idea that the nursing identity is unchangeable and the notion that 'a nurse will always be a nurse'. By doing so, the paper contributes to a debate on the supposed 'true' nature of the nursing identity and opens a discussion on the need for it to change.</p
Network explanations of the gender gap in migrants’ employment patterns:Use of online and offline networks in the Netherlands
No full textObjective: We investigate the relationship between the use of online and offline personal networks and employment for male and female migrants in the Netherlands. Background: Previous research indicated an alarmingly large gender gap in the employment patterns of migrants. Although social networks have been identified as being crucial for migrants’ labour market participation, we know very little about how migrant men and women differ in terms of their social networks, and how these differences translate into varying employment opportunities. Method: Drawing on the Dutch Immigrant Panel of LISS (Longitudinal Internet Studies for the Social Sciences) dataset, we used logistic regression analyses to examine the employment patterns of female migrants. Results: Our analyses generated two major findings. Contrary to our expectations, we found that, on average, the migrant women were more connected with individuals who were employed and had a Dutch background, but were less connected with men; and that they tended to have a rather dense network structure. Our findings further indicated that the women’s unemployment could not be significantly accounted for by their personal networks, but rather by their tendency to use LinkedIn that is less than the migrant men. Conclusion: Our findings have implications for understanding how inequalities in networks affect the labour market participation of migrant women
Rapid changes in DNA methylation associated with the initiation of reproduction in a small songbird
No full textSpecies with a circannual life cycle need to match the timing of their life history events to the environment to maximize fitness. However, our understanding of how circannual traits such as timing of reproduction are regulated on a molecular level remains limited. Recent studies have implicated that epigenetic mechanisms can be an important part in the processes that regulate circannual traits. Here, we explore the role of DNA methylation in mediating reproductive timing in a seasonally breeding bird species, the great tit (Parus major), using genome-wide DNA methylation data from individual females that were blood sampled repeatedly throughout the breeding season. We demonstrate rapid and directional changes in DNA methylation within the promoter region of several genes, including a key transcription factor (NR5A1) known from earlier studies to be involved in the initiation of timing of reproduction. Interestingly, the observed changes in DNA methylation at NR5A1 identified here are in line with earlier gene expression studies of reproduction in chicken, indicating that the observed shifts in DNA methylation at this gene can have a regulatory role. Our findings provide an important step towards elucidating the genomic mechanism that mediates seasonal timing of a key life history traits and provide support for the idea that epigenetic mechanisms may play an important role in circannual traits.</p
Flexible Working Memory Through Selective Gating and Attentional Tagging
No full textWorking memory is essential: it serves to guide intelligent behavior of humans and nonhuman primates when task-relevant stimuli are no longer present to the senses. Moreover, complex tasks often require that multiple working memory representations can be flexibly and independently maintained, prioritized, and updated according to changing task demands. Thus far, neural network models of working memory have been unable to offer an integrative account of how such control mechanisms can be acquired in a biologically plausible manner. Here, we present WorkMATe, a neural network architecture that models cognitive control over working memory content and learns the appropriate control operations needed to solve complex working memory tasks. Key components of the model include a gated memory circuit that is controlled by internal actions, encoding sensory information through untrained connections, and a neural circuit that matches sensory inputs to memory content. The network is trained by means of a biologically plausible reinforcement learning rule that relies on attentional feedback and reward prediction errors to guide synaptic updates. We demonstrate that the model successfully acquires policies to solve classical working memory tasks, such as delayed recognition and delayed pro-saccade/anti-saccade tasks. In addition, the model solves much more complex tasks, including the hierarchical 12-AX task or the ABAB ordered recognition task, both of which demand an agent to independently store and updated multiple items separately in memory. Furthermore, the control strategies that the model acquires for these tasks subsequently generalize to new task contexts with novel stimuli, thus bringing symbolic production rule qualities to a neural network architecture. As such, WorkMATe provides a new solution for the neural implementation of flexible memory control.</p
PCovR2:A flexible principal covariates regression approach to parsimoniously handle multiple criterion variables
No full textPrincipal covariates regression (PCovR) allows one to deal with the interpretational and technical problems associated with running ordinary regression using many predictor variables. In PCovR, the predictor variables are reduced to a limited number of components, and simultaneously, criterion variables are regressed on these components. By means of a weighting parameter, users can flexibly choose how much they want to emphasize reconstruction and prediction. However, when datasets contain many criterion variables, PCovR users face new interpretational problems, because many regression weights will be obtained and because some criteria might be unrelated to the predictors. We therefore propose PCovR2, which extends PCovR by also reducing the criteria to a few components. These criterion components are predicted based on the predictor components. The PCovR2 weighting parameter can again be flexibly used to focus on the reconstruction of the predictors and criteria, or on filtering out relevant predictor components and predictable criterion components. We compare PCovR2 to two other approaches, based on partial least squares (PLS) and principal components regression (PCR), that also reduce the criteria and are therefore called PLS2 and PCR2. By means of a simulated example, we show that PCovR2 outperforms PLS2 and PCR2 when one aims to recover all relevant predictor components and predictable criterion components. Moreover, we conduct a simulation study to evaluate how well PCovR2, PLS2 and PCR2 succeed in finding (1) all underlying components and (2) the subset of relevant predictor and predictable criterion components. Finally, we illustrate the use of PCovR2 by means of empirical data.</p
Technology to Improve Autonomy and Inform Housing Decisions for Older Adults With Memory Problems Who Live at Home in Canada, Sweden, and the Netherlands:Protocol for a Multipronged Mixed Methods Study
No full textBACKGROUND: Understanding the mobility patterns and experiences of older adults with memory problems living at home has the potential to improve autonomy and inform shared decision making (SDM) about their housing options.OBJECTIVE: We aim to (1) assess the mobility patterns and experiences of older adults with memory problems, (2) co-design an electronic decision support intervention (e-DSI) that integrates users' mobility patterns and experiences, (3) explore their intention to use an e-DSI to support autonomy at home, and (4) inform future SDM processes about housing options.METHODS: Informed by the Good Reporting of A Mixed Methods Study (GRAMMS) reporting guidelines, we will conduct a 3-year, multipronged mixed methods study in Canada, Sweden, and the Netherlands. For Phase 1, we will recruit a convenience sample of 20 older adults living at home with memory problems from clinical and community settings in each country, for a total of 60 participants. We will ask participants to record their mobility patterns outside their home for 14 days using a GPS tracker and a travel diary; in addition, we will conduct a walking interview and a final debrief interview after 14 days. For Phase 2, referring to results from the first phase, we will conduct one user-centered co-design process per country with older adults with memory issues, caregivers, health care professionals, and information technology representatives informed by the Double Diamond method. We will ask participants how personalized information about mobility patterns and experiences could be added to an existing e-DSI and how this information could inform SDM about housing options. For Phase 3, using online web-based surveys, we will invite 210 older adults with memory problems and/or their caregivers, split equally across the three countries, to use the e-DSI and provide feedback on its strengths and limitations. Finally, in Phase 4, we will triangulate and compare data from all phases and countries to inform a stakeholder meeting where an action plan will be developed.RESULTS: The study opened for recruitment in the Netherlands in November 2018 and in Canada and Sweden in December 2019. Data collection will be completed by April 2021.CONCLUSIONS: This project will explore how e-DSIs can integrate the mobility patterns and mobility experiences of older adults with memory problems in three countries, improve older adults' autonomy, and, ultimately, inform SDM about housing options.TRIAL REGISTRATION: ClinicalTrials.gov NCT04267484; https://clinicaltrials.gov/ct2/show/NCT04267484.INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/19244.</p
Association of homozygous variants of STING1 with outcome in human cervical cancer
No full textDNA-sensing receptor Cyclic GMP-AMP Synthase (cGAS) and its downstream signaling effector STimulator of INterferon Genes (STING) have gained significant interest in the field of tumor immunology, as a dysfunctional cGAS-STING pathway is associated with poor prognosis and worse response to immunotherapy. However, studies so far have not taken into account the polymorphic nature of the STING-encoding STING1 gene. We hypothesized that the presence of allelic variance in STING1 would cause variation between individuals as to their susceptibility to cancer development, cancer progression, and potential response to (immuno)therapy. To start to address this, we defined the genetic landscapes of STING1 in cervical scrapings and investigated their corresponding clinical characteristics across a unique cohort of cervical cancer patients and compared them with independent control cohorts. Although we did not observe an enrichment of particular STING1 allelic variants in cervical cancer patients, we did find that the occurrence of homozygous variants HAQ/HAQ and R232H/R232H of STING1 were associated with both younger age of diagnosis and higher recurrence rate. These findings were accompanied by worse survival, despite comparable mRNA and protein levels of STING and numbers of infiltrated CD8(+) T cells. Our findings suggest that patients with HAQ/HAQ and R232H/R232H genotypes may have a dysfunctional cGAS-STING pathway that fails to promote efficient anticancer immunity. Interestingly, the occurrence of these genotypes coincided with homozygous presence of the V48V variant, which was found to be individually associated with worse outcome. Therefore, we propose V48V to be further evaluated as a novel prognostic marker for cervical cancer.</p