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Carbon dioxide and gaseous nitrogen emissions from biochar‐amended soils under wastewater irrigated urban vegetable production of Burkina Faso and Ghana
(2020-06-30)
To quantify carbon (C) and nitrogen (N) losses in soils of West African urban and peri‐urban agriculture (UPA) we measured fluxes of CO₂‐C, N₂O‐N, and NH₃‐N from irrigated fields in Ouagadougou, Burkina Faso, and Tamale, Ghana, under different fertilization and (waste‐)water regimes. Compared with the unamended control, application of fertilizers increased average cumulative CO₂‐C emissions during eight cropping cycles in Ouagadougou by 103% and during seven cropping cycles in Tamale by 42%. Calculated total emissions ...
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Comparing the effects of generating questions, testing, and restudying on students' long‐term recall in university learning
(2020-01-21)
We compared the long‐term effects of generating questions by learners with answering questions (i.e., testing) and restudying in the context of a university lecture. In contrast to previous studies, students were not prepared for the learning strategies, learning content was experimentally controlled, and effects on factual and transfer knowledge were examined. Students' overall recall performance after one week profited from generating questions and testing but not from restudying. When analyzing the effects on both ...
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The effect of environmental sustainability on credit risk
(2020-03-07)
The European Commission has proposed establishing a framework that redirects capital to sustainable investments in order to foster sustainable economic growth. A key proposal from this framework is the mandatory consideration of environmental criteria for investment decisions. However, in particular for bond investors, there is not much academic guidance on how to integrate sustainability criteria in the investment process. Hence, this study investigates the impact of environmental sustainability on the pricing of ...
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No Robust Effect of Distributed Practice on the Short- and Long-Term Retention of Mathematical Procedures
(2020-04-29)
We investigated the effect of distributed practice and more specifically the “lag effect” concerning the retention of mathematical procedures. The lag effect implies that longer retention intervals benefit from longer inter-study intervals (ISIs). University students (N = 235) first learned how to solve permutation tasks and then practiced this procedure with an ISI of zero (i.e., massed), one, or 11 days. The final test took place after one or five weeks. All conditions were manipulated between-subjects. Contrary ...
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The Role of Institutional Uncertainty for Social Sustainability of Companies and Supply Chains
(2020-04-06)
Global sourcing largely occurs from so-called emerging markets and developing economies (EMDEs). In these contexts, substantial leverage effects for sustainability in supply chains (SCs) can be expected by reducing adverse impacts on society and minimising related risks. For this ethical end, an adequate understanding of the respective sourcing contexts is fundamental. This case study of South Africa’s (SA) mining sector uses institutional theory and the notion of institutional uncertainty to empirically analyse the ...
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Biomass Performance and Competition Effects in an Established Temperate Agroforestry System of Willow and Grassland—Results of the 2nd Rotation
(2020-11-19)
Agroforestry systems (AFSs) are promoted as environmentally friendly and climate-change-resilient cultivation systems with the potential of increasing ecosystem services. Especially under temperate climatic conditions, the implementation in agricultural practice is low so far, inter alia due to the lack of knowledge regarding longer-term effects of such systems. This study investigated biomass yields and crop development during the second rotation of an alley cropping system with willows (clone “Tordis” ((Salix ...
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Diversity of Trametes (Polyporales, Basidiomycota) in tropical Benin and description of new species Trametes parvispora
(2020-03-10)
Trametes is a globally distributed genus of white-rot polypores and well sampled in temperate and boreal areas. However, the diversity, taxonomy, and phylogenetic positions of Trametes spp. are poorly known in tropical Africa. This study aims at documenting the diversity of Trametes species in Benin (tropical Africa) and their phylogenetic positions with a focus on the T. elegans species complex. Therefore, we collected specimens of Trametes from different forest types across Benin. To infer phylogenetic relationships ...
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A note on dual prehomomorphisms from a group into the Margolis–Meakin expansion of a group
(2020-08-07)
We give a category-free order theoretic variant of a key result in Auinger and Szendrei (J Pure Appl Algebra 204(3):493–506, 2006) and illustrate how it might be used to compute whether a finite X-generated group H admits a canonical dual prehomomorphism into the Margolis–Meakin expansion M(G) of a finite X-generated group G. We show that for G the Klein four-group a suitable H must be of exponent 6 at least and recapture a result of Szakács.
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Molecular Basis for Ser/Thr Specificity in PKA Signaling
(2020-06-25)
cAMP-dependent protein kinase (PKA) is the major receptor of the second messenger cAMP and a prototype for Ser/Thr-specific protein kinases. Although PKA strongly prefers serine over threonine substrates, little is known about the molecular basis of this substrate specificity. We employ classical enzyme kinetics and a surface plasmon resonance (SPR)-based method to analyze each step of the kinase reaction. In the absence of divalent metal ions and nucleotides, PKA binds serine (PKS) and threonine (PKT) substrates, ...
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Sphaeropsis sapinea and fungal endophyte diversity in twigs of Scots pine (Pinus sylvestris) in Germany
(2020-09-03)
Sphaeropsis sapinea is the causal fungal agent of Diplodia tip blight disease of Scots pine (Pinus sylvestris) and other coniferous trees of relevance to forestry in Germany. In this study, the distribution and occurrence of S. sapinea and accompanying endophytic fungi in twigs of healthy and diseased Scots pine was investigated on a spatial and temporal scale. Sampling of 26,000 twig segments from trees in 105 temperate coniferous forest stands in Germany resulted in isolation of 33,000 endophytic fungi consisting ...