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Using games to improve students' engagement and understanding of statistics in Higher Education
No full textIn this article we present a series of light-touch, easy to implement, classroom activities designed to improve students’ understanding and interpretation of regression coefficients. Using an experiment, we evaluate the effectiveness of the activities by randomly allocating first-year undergraduate students into a seminar with the activities (treatment group) or not (control group). We demonstrate that the classroom activities have a large, positive effect on several domains including engagement (measured by seminar attendance), enjoyment of learning (measured by an end-of-term student satisfaction survey), and their understanding of the material (measured by test scores). These results suggest that adopting more varied pedagogical approaches to teaching statistics/econometrics can benefit students
Retinal spike train decoder using vector quantization for visual scene reconstruction
No full textThe retinal impulse signal is the basic carrier of visual information. It records the distribution of light on the retina. However, its direct conversion to a scene image is difficult due to the nonlinear characteristics of its distribution. Therefore, the use of artificial neural network to reconstruct the scene from retinal spikes has become an important research area. This paper proposes the architecture of a neural network based on vector quantization, where the feature vectors of spike trains are extracted, compressed, and stored using a feature extraction and compression network. During the decoding process, the nearest neighbour search method is used to find the nearest feature vector corresponding to each feature vector in the feature map. Finally, a reconstruction network is used to decode a new feature map composed of matching feature vectors to obtain a visual scene. This paper also verifies the impact of vector quantization on the characteristics of pulse signals by comparing experiments and visualizing the characteristics before and after vector quantization. The network delivers promising performance when evaluated on different datasets, demonstrating that this research is of great significance for improving relevant applications in the fields of retinal image processing and artificial intelligence
Influence of uncalcined coal gangue on the microstructure and properties of magnesium ammonium phosphate cement
No full textThis paper proposes a new method of reusing uncalcined coal gangue (UCG) as a mineral admixture in the magnesium ammonium phosphate cement (MAPC) blended with fly ash (FA). The effects of UCG on setting time, workability, hydration heat release, mechanical properties, hydration products and microstructure of MAPC composites were systematically investigated. The results indicate that the addition of UCG decreased the maximum hydration temperature and extended the setting time of MAPC composites. The compressive strength of MAPC was improved by introducing an optimal amount of UCG. The XRD results showed no new crystal phase in UCG-0 (with 20%FA and 0% UCG) and some secondary hydration products, such as berlinite and lizardite, were observed in MAPC with UCG. The addition of UCG was found to inhibit the generation of dittmarite and promote the development of struvite. Based on the results, it could be determined that differences in the crystal morphology of struvite and dittmarite influence the compressive strength of MAPC composites
Genetic variation of turnip yellows virus in arable and vegetable brassica crops, perennial wild brassicas and aphid vectors collected from the plants
No full textTurnip yellows virus (TuYV; Polerovirus, Solemoviridae) infects and causes yield losses in a range of economically important crop species, particularly the Brassicaceae. It is persistently transmitted by several aphid species and is difficult to control. Although the incidence and genetic diversity of TuYV has been extensively investigated in recent years, little is known about how the diversity within host plants relates to that in its vectors. Arable oilseed rape (Brassica napus) and vegetable brassica plants (Brassica oleracea), wild cabbage (B. oleracea), and aphids present on these plants were sampled in the field in three regions of the United Kingdom. High levels of TuYV (82 to 97%) were detected in plants in all three regions following enzyme-linked immunosorbent assays. TuYV was detected by reverse transcription polymerase chain reaction in Brevicoryne brassicae aphids collected from plants, and TuYV sequences were obtained. Two TuYV open reading frames, ORF0 and ORF3, were partially sequenced from 15 plants, and from one aphid collected from each plant. Comparative analyses between TuYV sequences from host plants and B. brassicae collected from respective plants revealed differences between some ORF0 sequences, which possibly indicated that at least two of the aphids might not have been carrying the same TuYV isolates as those present in their host plants. Maximum likelihood phylogenetic analyses including published, the new TuYV sequences described above, 101 previously unpublished sequences of TuYV from oilseed rape in the United Kingdom, and 13 also previously unpublished sequences of TuYV from oilseed rape in Europe and China revealed three distinct major clades for ORF0 and one for ORF3, with some distinct subclades. Some clustering was related to geographic origin. Explanations for TuYV sequence differences between plants and the aphids present on respective plants and implications for the epidemiology and control of TuYV are discussed
App-based intervention for parents of children with crying, sleeping, and feeding problems : usability, usefulness and implications for improvement
Get PDFThere is a lack of evidence-based app guidance for parents of children with crying, sleeping, and feeding problems who are often highly burdened and not likely to seek professional help. A new psychoeducational app for parents providing scientifically sound information via text and videos, a diary function, selfcare strategies, a chat forum and a regional directory of specialized counseling centers may serve as a low-threshold intervention for this target group. We investigated how parents perceived the app in terms of the following: (1) overall impression and usability, (2) feedback on specific app functions regarding usefulness and (3) possible future improvements. Our clinical sample of = 137 parents of children aged from 0 to 24 months was recruited from a cry baby outpatient clinic in Southern Germany between 2019 and 2022. A convergent parallel mixed methods design was used to collect and analyse cross-sectional data on app evaluation. After app use within the framework of a clinical trial, parents filled in an app evaluation questionnaire. Most participants used the app at least once a week (86, 62.8 %) over an average period of 19.06 days ( = 15.00). Participants rated overall impression and usability as good, and the informational texts, expert videos and regional register of counseling centers as appealing and useful. The diary function and chat forum were found to be helpful in theory, but improvements in implementation were requested, such as a timer function for the diary entry. Regarding future functionality, parents posed several suggestions such as the option to contact counseling centers directly via app, and the inclusion of the profile of their partners. Positive ratings of overall impression, usability, and specific app functions are important prerequisites for the app to be effective. App-based guidance for this target group should include easy-to-use information. The app is intended to serve as a secondary preventive low-threshold offer and to complement professional counseling
Multi‐scale characterization and analysis of cellular viscoelastic mechanical phenotypes by atomic force microscopy
No full textThe viscoelasticity of cells serves as a biomarker that reveals changes induced by malignant transformation, which aids the cytological examinations. However, differences in the measurement methods and parameters have prevented the consistent and effective characterization of the viscoelastic phenotype of cells. To address this issue, nanomechanical indentation experiments were conducted using an atomic force microscope (AFM). Multiple indentation methods were applied, and the indentation parameters were gradually varied to measure the viscoelasticity of normal liver cells and cancerous liver cells to create a database. This database was employed to train machine‐learning algorithms in order to analyze the differences in the viscoelasticity of different types of cells and as well as to identify the optimal measurement methods and parameters. These findings indicated that the measurement speed significantly influenced viscoelasticity and that the classification difference between the two cell types was most evident at 5 μm/s. In addition, the precision and the area under the receiver operating characteristic curve were comparatively analyzed for various widely employed machine‐learning algorithms. Unlike previous studies, this research validated the effectiveness of measurement parameters and methods with the assistance of machine‐learning algorithms. Furthermore, the results confirmed that the viscoelasticity obtained from the multiparameter indentation measurement could be effectively used for cell classification.Research Highlights This study aimed to analyze the viscoelasticity of liver cancer cells and liver cells. Different nano‐indentation methods and parameters were used to measure the viscoelasticity of the two kinds of cells. The neural network algorithm was used to reverse analyze the dataset, and the methods and parameters for accurate classification and identification of cells are successfully found
Online systemic energy management strategy of fuel cell system with efficiency enhancement
Get PDFTemperature plays a crucial role in efficiency improvement and lifespan extension of the fuel cell system which encourages energy management strategy (EMS) taking thermal into consideration. However, sluggish thermal response prevents the fuel cell performance from tracking the optimal states during scenarios with significant power variations, which was disregarded in the previous works. To solve this issue, an online hydrogen consumption minimization guarantee strategy (HCMG) including thermal management is proposed which is divided into two parts: 1) primary power distribution strategy, where a model predictive control (MPC) based EMS is employed herein to distribute power between fuel cell and battery with the objectives of minimizing hydrogen consumption as well as maintaining the state of charge (SOC), and 2) HCMG, where a modified MPC based method is exploited herein to track the reference power and optimal temperature with minimum hydrogen consumption by adjusting both the duty cycle of fan and fuel cell current. The presented approach ascertains hydrogen consumption reduction for 3.448% even under relatively extensive power changes, during which the temperature cannot reach the optimal value in a brief time. The real-time simulation results show the effectiveness of the proposed technique compared with previous EMS methods under various driving cycles
Has the war in Ukraine changed Europeans’ preferences on refugee policy? Evidence from a panel experiment in Germany, Hungary and Poland
Get PDFThe Russian invasion of Ukraine in early 2022 resulted in the largest refugee crisis in Europe since WWII. Using a unique panel conjoint experiment on refugee policy preferences carried out in Germany, Poland and Hungary just before and after the onset of the war in Ukraine, we show a heterogenous response to the influx of refugees from Ukraine across the three countries: no change of policy preferences in Germany, moderate change in Hungary and a significant change in Poland. Our results have direct implications for the development of a common EU asylum policy, as even though the countries persistently diverge on the preferred mode of asylum seekers’ allocation, with Germans favouring relocation and Poland and Hungary the status quo, the results highlight the scope for consensus rooted in shared preference for the asylum seekers’ unrestricted access to the labour market. This dimension consistently emerges as the most important policy dimension in all three countries before and after the outbreak of war
Walking a thin line : a reputational account of green central banking
No full textIn this article, we provide a comparative case study analysis of the differentiated climate change engagement of the Bank of England (BoE), European Central Bank (ECB) and Federal Reserve (Fed). Drawing on semi-structured interviews and a newly composed database of central banker speeches and legislative documents, we argue that climate (in)actions of these central banks are shaped by concerns over their reputation. A broad socio-political consensus on the need for climate change mitigation enabled the BoE and ECB to begin integrating CRFRs into their supervisory frameworks without affecting their socio-political reputation while the carbon bias in their own asset purchase programs compelled both central banks to also start greening their monetary policy to preserve their performative reputation. The Fed’s more cautious moves have been driven by a fear of loss of technical reputation in the face of a growing transnational consensus on the financial stability risks of climate change
On the rotation of a Savonius turbine at low Reynolds numbers subject to Kolmogorov cascade of turbulence
No full textWith an increasing demand for small energy generation in urban areas, small-scale Savonius wind turbines are growing their share rapidly. In such an environment, Savonius turbines are exposed to low mean velocity with highly turbulent flows made by complex geographies. Here, we report the flow-induced rotation of a Savonius turbine in a highly turbulent flow (18% turbulence intensity). The high turbulence is realized by using the far-field of an open-jet. Compared to low turbulence inflow (1% turbulence intensity), the turbine rotates 4% faster in high turbulence since the torque/power increases with turbulence intensity. The wake measurement by hot-wire anemometry and particle image velocimetry reveals the suppression of vortex shedding in high turbulence. In addition, a newly developed semi-empirical low-order model, which can include the effect of turbulence intensity and integral length scale, also confirms high turbulence intensity contributes to the rotation of the turbine. These results will boost more installation of small Savonius turbines in urban areas in the future