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Generation of active neurons from mouse embryonic stem cells using retinoic acid and purmorphamine
Get PDFMultiple differentiation protocols have emerged in recent years, producing neurons with diverse morphologies, gene and protein expression profiles, and functionality. Many of these differentiation techniques require months of culture and the use of expensive growth factors. Most importantly, the derived neurons usually do not exhibit any electrical activity. This limits the value of the protocol as a tool for engineering and investigating neural networks. Here, we describe an efficacious method for differentiating mouse embryonic stem cells into functional neurons. CGR8 cells were neurally induced via the simultaneous application of retinoic acid and purmorphamine. The derived cells expressed neuronal (TUJ1 and NeuN) and synaptic (GAD2, PSD-95, Synaptophysin, and VGLUT1) markers. During whole-cell recordings, neurons exhibited inward and outward currents, likely caused by fast-inactivating voltage-gated potassium channels. Upon current injection, miniature action potentials were also recorded. The efficient generation of diverse subtypes of functional neurons can be a useful tool in fundamental investigations of neural network activity and translational studies
City-level institutions and perceived entrepreneurial ecosystem’s growth orientation
Get PDFThis study uses both secondary and primary data on perceptions of 1789 ecosystem actors from 17 cities in Europe to perform an empirical analysis of three institutional dimensions: regulatory, cultural values and socio-cultural practices – and tests their association with the entrepreneurial ecosystem’s growth orientation. As a result, we develop a framework for the entrepreneurial ecosystem’s factors and provide policy recommendations for those interested in supporting the entrepreneurial ecosystem’s growth orientation in cities. Among other conclusions, the findings suggest a positive association between the socio-cultural practices of environmental sustainability behaviour in businesses with entrepreneurial ecosystem’s growth orientation
Perennial flower strips can be a cost‐effective tool for pest suppression in orchards
Get PDFFlower strips can provide many economic benefits in commercial orchards, including reducing crop damage by a problematic pest, rosy apple aphid ( Dysaphis plantaginea [Passerini]). To explore the financial costs and benefits of this effect, we developed a bio‐economic model to compare the establishment and opportunity costs of perennial wildflower strips with benefits derived from increased yields due to reduced D. plantaginea fruit damage under high and low pest pressure. This was calculated across three scenarios: (1) a flower strip on land that would otherwise be an extension of the standard grass headland, (2) a flower strip on land that could otherwise be used to produce apples and (3) a flower strip in the centre of an orchard. Through reduction of D. plantaginea fruit damage alone, our study shows that flower strips on the headland can be a positive financial investment. If non‐crop land was not available, establishment of a flower strip in the centre of an orchard, instead of the edge, could recoup opportunity costs by providing benefits to crops on both sides of the flower strip. Our study can help guide the optimal placement of flower strips and inform subsidy value for these schemes
Atmospheric electricity data from Lerwick during 1964 to 1984
Get PDFA dataset of the atmospheric Potential Gradient (PG) from Lerwick observatory in Shetland is now available, which provides hourly-averaged PG for each month, from January 1964 to July 1984. The measurements were made consistently, with calibrated and well-maintained instrumentation. Co-located meteorological observations are also available from the same site, where disturbing effects of air pollution are small. Other sources of atmospheric data such as satellite observations became increasing abundant during the era of the measurements, making broader comparisons possible. On average, the Lerwick PG measurements contain a diurnal cycle characteristic of the global circuit, and show relationships with the El Niño-Southern Oscillation (ENSO), especially in December. The value of the data is in the information it contains about the global atmospheric electric circuit, which is embedded in the climate system
A two stream radiative transfer model for vertically inhomogeneous vegetation canopies including internal emission
Get PDFTwo stream models of radiative transfer are used in the land surface schemes of climate and Earth system models to represent the interaction of solar and terrestrial radiation with vegetation canopies. This is done both to model the surface energy balance and the photosynthetic flux of carbon into the terrestrial biosphere. Two stream models are especially attractive for inclusion in large complex models of the Earth as they allow for an analytical and computationally cheap solution to the radiative transfer problem, whilst accounting for all orders of photon scattering and hence preserving energy balance. As the vegetation processes described in land surface models become more complex, new two stream formulations are required to correctly represent radiative components. For example, as ecosystem demography becomes more prevalent in land models, the need to represent canopies with vertically varying structure becomes more important, but an analytical, efficient solution to the transfer problem is still desirable. Here we describe a two stream scheme constructed from layers with independent optical properties. It is physically consistent with the existing radiative transfer schemes in many current land surface models, with typical differences in the order of
in normalized flux units, and its solution is analytical. The model can be used to represent complex canopy structures and its formulation lends itself to modeling the canopy leaving flux arising from internal emissions, for example, longwave radiation or fluorescence. We also discuss the parameterization of two stream schemes and demonstrate that this could be improved in existing models
'To know that you are a link in the chain': a realist evaluation to explore how digital, intensive, parent-implemented interventions work for children with speech sound disorder, why, and for whom
Get PDFIntroduction
Children with moderate to severe speech sound disorder (SSD) need intensive therapy to increase intervention effectiveness and efficiency. However, worldwide speech and language therapists (SLTs) report that it is difficult to implement recommended intervention intensities in clinical practice. Supporting parents/carers to deliver home-intervention, facilitated through digital tools, has potential to circumvent these difficulties and increase practice intensity. This realist evaluation builds on our earlier realist review on intensive, digital, parent-implemented interventions for children with SSD through exploring the experiences of stakeholders to optimally understand what might work best, for whom, and why in clinical practice.
Methods
We undertook a realist evaluation to test and refine our initial programme theories developed in our earlier realist review through focus groups with key stakeholders. Five focus groups were conducted with SLTs (n=22), and two focus groups with parents/carers of children with SSD aged 4-5 years (n=6). A realist methodology approach was used to collect and analyse the data, including the development of context-mechanism-outcome configurations. Middle-range theories of adult-learning, self-efficacy, and parenting styles were used to develop our theoretical thinking.
Results
Programme theories from the earlier realist review about how the intervention works were refined, refuted, or confirmed. The refined theories are presented across three areas to demonstrate the journey of engaging in a digital, intensive parent-implemented intervention: 1. Readiness to engage; 2. Realisation of the intervention; and 3. Sustaining momentum. The theories offer insight into mechanisms that support and train families to engage in home-practice through digital tools, including important contextual factors needing consideration in implementation.
Conclusion
Digital, intensive, parent-implemented interventions for children with SSD have potential to improve the effectiveness and efficiency of SLT services in certain contexts and improve children’s outcomes worldwide. Mechanisms of change, and impactful contexts at each point of the journey of involvement need consideration to successfully empower and support parents/carers and their children with SSD
Impacts of spatial expansion of urban and rural construction on typhoon-directed economic losses: should land use data be included in the assessment?
Get PDFWith the intensification of global climate change, the frequent occurrence of typhoon disaster events has become a great challenge to the sustainable development of cities around the world; thus, it is of great significance to carry out the assessment of typhoon-directed economic losses. Typhoon disaster loss assessment faces key challenges, including complex regional environments, scarce historical data, difficulties in multi-source heterogeneous data fusion, and challenges in quantifying assessment uncertainties. Meanwhile, existing studies often overlook the complex relationship between the spatial expansion of urban and rural construction (SEURC) and typhoon disaster losses, particularly their differential manifestations across different regions and disaster intensities. To address these issues, this study proposes CLPFT (Comprehensive Uncertainty Assessment Framework for Typhoon), an innovative assessment framework integrating prototype learning and uncertainty quantification through a UProtoMLP neural network. Results demonstrate three key findings: (1) By introducing prototype learning, a meta-learning approach, to guide model updates, we achieved precise assessments with small training samples, attaining an MAE of 1.02, representing 58.5–76.1% error reduction compared to conventional machine learning algorithms. This reveals that implicitly classifying typhoon disaster loss types through prototype learning can significantly improve assessment accuracy in data-scarce scenarios. (2) By designing a dual-path uncertainty quantification mechanism, we realized high-reliability risk assessment, with 95.45% of actual loss values falling within predicted confidence intervals (theoretical expectation: 95%). This demonstrates that the dual-path uncertainty quantification mechanism can provide statistically credible risk boundaries for disaster prevention decisions, significantly enhancing the practical utility of assessment results. (3) Further investigation through controlling dynamic assessment factors revealed significant regional heterogeneity in the relationship between SEURC and directed economic losses. Furthermore, the study found that when typhoon intensity reaches a critical value, the relationship shifts from negative to positive correlation. This indicates that typhoon disaster loss assessment should consider the interaction between urban resilience and typhoon intensity, providing important implications for disaster prevention and mitigation decisions. This paper provides a more comprehensive and accurate assessment method for evaluating typhoon disaster-directed economic losses and offers a scientific reference for determining the influencing factors of typhoon-directed economic loss assessments
A systemic risk assessment methodological framework for the global polycrisis
Get PDFHuman societies and ecological systems face increasingly severe risks, stemming from crossing planetary boundaries, worsening inequality, rising geo-political tensions, and new technologies. In an interconnected world, these risks can exacerbate each-other, creating systemic risks, which must be thoroughly assessed and responded to. Recent years have seen the emergence of analytical frameworks designed specifically for, or applicable to, systemic risk assessment, adding to the multitude of tools and models for analysing and simulating different systems. By assessing two recent global food and energy systemic crises, we propose a methodological framework applicable to assessing systemic risks in a polycrisis context, drawing from and building on existing approaches. Our framework’s polycrisis-specific features include: exploring system architectures including their objectives and political economy; consideration of transformational responses away from risks; and cross-cutting practices including consideration of non-human life, trans-disciplinarity, and diversity, transparency and communication of uncertainty around data, evidence and methods
Ensemble Kalman filter in latent space using a variational autoencoder pair
No full textPopular (ensemble) Kalman filter data assimilation (DA) approaches assume that the errors in both the a priori estimate of the state and those in the observations are Gaussian. For constrained variables, e.g. sea ice concentration or stress, such an assumption does not hold. The variational autoencoder (VAE) is a machine learning (ML) technique that allows to map an arbitrary distribution to/from a latent space in which the distribution is supposedly closer to a Gaussian. We propose a novel hybrid DA-ML approach in which VAEs are incorporated in the DA procedure. Specifically, we introduce a variant of the popular ensemble transform Kalman filter (ETKF) in which the analysis is applied in the latent space of a single VAE or a pair of VAEs. In twin experiments with a simple circular model, whereby the circle represents an underlying submanifold to be respected, we find that the use of a VAE ensures that a posteriori ensemble members lie close to the manifold containing the truth. Furthermore, online updating of the VAE is necessary and achievable when this manifold varies in time, i.e. when it is non-stationary. We demonstrate that introducing an additional second latent space for the observational innovations improves robustness against detrimental effects of non-Gaussianity and bias in the observational errors but it slightly lessens the performance if observational errors are strictly Gaussian