Design of fibre reinforced PV concepts for building integrated applications

Fibre reinforced polymers present an interesting encapsulation medium for PV-modules. Glass fibres can provide increased strength and stiffness to thin polymer layers overcoming the brittleness and limited deformability of glass-panes. Glass fibre reinforced polymers allows for transparency over a broad range of the solar spectrum while the material properties and integral production processes create possibilities for novel product concepts with embedded PV technology. To explore such possibilities, innovative design methods were used to design novel PV product concepts for applications in the build environment.\ud In our paper three conceptual designs are presented; (1) a thin film module with an adjoining interconnection system functioning as structural element for geodetic roofing structures, (2) a PV lamella with single-axis tracking utilizing a linear concentration effect caused by the geometry of the product and the materials applied, and (3) a prepreg PV-material which allows for easy shaping during the production of PV modules with complex geometries. Each concept employs a specific PV technology and demonstrates a possible application aimed at a specific market. In this way we show the potential of integration of PV technology in fibre reinforced composites. The paper will be illustrated by concept renderings

Model-independent study of the QCD sum rule for the pi NN coupling constant

We reinvestigate the QCD sum rule for the pi NN coupling constant, g, starting from the vacuum-to-pion matrix element of the correlation function of the interpolating fields of two nucleons. We study in detail the physical content of the correlation function without referring to the effective theory. We consider the invariant correlation functions by splitting the correlation function into different Dirac structures. We show that the coefficients of the double-pole terms are proportional to g but that the coefficients of the single-pole terms are not determined by g. In the chiral limit the single-pole terms as well as the continuum terms are ill defined in the dispersion integral. Therefore, the use of naive QCD sum rules obtained from the invariant correlation functions is not justified. A possible procedure to avoid this difficulty is discussed.Comment: 20 pages, 2 figure

The Pion-Nucleon Coupling Constant in QCD Sum Rules

The pion-nucleon coupling constant $g_{\pi N}$ is studied on the basis of the QCD sum rules. Both the Borel sum rules and the finite energy sum rules for $g_{\pi N}$ are used to examine the effects of higher dimensional operators (up to dim. 7) and $\alpha_s$ corrections in the operator product expansion. Agreement with the experimental number is reached only when $S_{\pi}/S_N$ is greater than one, where $S_{\pi}$ ($S_N$) is the continuum threshold for the $g_{\pi N}$ (nucleon) sum rule.Comment: 15 pages, latex, 9 figures appended as uu-encoded fil

Citizen science against the plastic soup: background, motivation and expectations of volunteers studying plastic pollution on Dutch riverbanks

In the field of investigating and addressing plastic pollution, the public is increasingly involved in research as citizen scientists. Long-term monitoring for this topic is needed, and recruiting and retaining volunteers is challenging. Therefore, it is important to learn more about the demographic background, motivations and expectations of involved citizen scientists, and if these change during participation. Our research studied these aspects of the citizen scientists in the Dutch Clean Rivers project, who monitor plastic pollution on riverbanks. Participants (n = 122) completed pre- and post-survey after one year of the project. While there was no gender bias, the participants were mostly middle-aged and highly educated, and almost half had previous experience with scientific research. Their motivation to participate was mostly activistic, as they wanted to tackle the source of plastic pollution and contribute to solutions. More personal motivations, such as wanting to learn more and because it is fun to do scientific research, decreased significantly after one year of participation. Their expectations were in line with the main motivations. Understanding the background, motivations and expectations of volunteers helps this project, and the field of citizen science in plastic pollution research

Learning Analytics and Online Language learning

This chapter addresses the challenges and future potential of learning analytics. It examines some of the key questions raised by the research literature that will influence language education over the next decade, and investigates what kind of data can be used to inform effective decision-making in online language-learning contexts and how it can be visualized. The chapter turns to consider preliminary data arising from the needs analysis phase of the VITAL Project (Visualization Tools and Analytics to Monitor Online Language Learning and Teaching), a two-year EU-funded project that specifically addresses the gap in the research literature on analytics in language learning and teaching. Turning to the first large-scale project on learning analytics and online language learning, Link & Li's theoretical framework provides a useful starting point to consider the role of dashboards for language learners and instructors

Calculation of coupling constant g_phi-pi-gamma in QCD sum rules

The coupling constant of g_phi-pi-gamma decay is calculated in the method of QCD sum rules. A comparison of our prediction on the coupling constant with the result obtained from analysis of the experimental data is performed.Comment: 6 pages, 3 figure

Assessment of Different Expression Strategies for the Production of a Recombinant Lipoprotein Vaccine in Plants

The ability of plants to serve as a production system for bacterial lipoprotein vaccines has been investigated. First, the effect of high-level expression of the Borrelia burgdorferi outer membrane protein A (OspA), a prototype vaccine against Lyme disease, has been examined by a proteomics approach. Analysis by 2D-PAGE of wild type tobacco plants and transplastomic plants accumulating recombinant OspA showed no apparent differences in protein pattern except for OspA. However, presence of the bacterial signal sequence limits transgene accumulation. As an alternative approach OspA was produced in Nicotiana benthamiana plants by transient expression via a deconstructed tobacco mosaic virus-based system. While rapid expression of OspA could be achieved, no palmitoylation occurred with the genuine bacterial sequence. In contrast, modification of the N-terminus with an eukaryotic sequence motif resulted in palmitoylation of OspA. This study shows that plants provide multiple expression strategies and could serve as a versatile production platform for recombinant lipidated subunit vaccines

Situational Voluntary Compliance: Adherence to COVID-19 Social Distancing Guidelines in the 2020 Local Outbreak in Beijing

To mitigate the COVID-19 pandemic many countries have adopted mandatory social distancing measures, but in China, social distancing was implemented only as an advisory guideline. This article seeks to understand whether, and why Chinese citizens adhered to such social distancing advice. The data, derived from a survey in the 2020 local outbreak in Beijing, show that voluntary compliance was hardly influ-enced by motivational predictors, but was almost exclusively dependent on a single, key situational predictor, namely people’s practical capacity to follow social distancing. These findings demonstrate that the emphasis on intrinsic and extrinsic motivations in existing compliance research does not do justice to the situational nature of voluntary compliance observed within this particular context. We discuss theoretical implications of these findings for the compliance literature. Moreover, we use these findings to provide (tentative) insight into the compliance challenges that China was facing during the course of the pandemic, and to speculate about ways in which compliance may be enhanced during future pandemic outbreaks in China.</p