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Synthesis and characterization of a tertiary amine:boric acid (1:1) co-crystal and a neutral zwitterionic diamine pentaboron adduct
Get PDFThe syntheses of the 4,4’-trimethylenebis(N-methylpiperidine):boric acid (1:1) co-crystal, 4,4’-(1-MeNC5H9)2(CH2)3.B(OH)3 (1), and a zwitterionic tetrahydroxidohexaoxidopentaboron adduct, [B5O6(OH)4(N-NH2CH2CH2NHEt2).H2O (2), (NH2CH2CH2NEt2 = deen) from appropriate combinatorial libraries primed with B(OH)3, are reported together with their spectroscopic (NMR, IR) and single-crystal XRD characterization data. Solid-state H-bond interactions are the likely strong drivers for their formation, and these are described in detail. H-bond networks present in co-crystal 1 include C22(16), R22(8), and R66(36) whilst zwitterionic pentaboron derivative 2 has three R22(8) intermolecular H-bond interactions and the Et2NH- group is involved in a S(7) intramolecular H-bond. Thermal (TGA/DSC) data are also reported for 1 which thermally decomposes to B2O3, in a multistage process: dehydration (60-70 oC) and oxidation and further dehydration (90-700 oC)
Deep-C storage: Biological, chemical and physical strategies to enhance carbon stocks in agricultural subsoils
Get PDFDue to their substantial volume, subsoils contain more of the total soil carbon (C) pool than topsoils. Much of this C is thousands of years old, suggesting that subsoils offer considerable potential for long-term C sequestration. However, knowledge of subsoil C behaviour and manageability remains incomplete, and subsoil C storage potential has yet to be realised at a large scale, particularly in agricultural systems. A range of biological (e.g. deep-rooting), chemical (e.g. biochar burial) and physical (e.g. deep ploughing) C sequestration strategies have been proposed, but are yet to be assessed. In this review, we identify the main factors that regulate subsoil C cycling and critically evaluate the evidence and mechanistic basis of subsoil strategies designed to promote greater C storage, with particular emphasis on agroecosystems. We assess the barriers and opportunities for the implementation of strategies to enhance subsoil C sequestration and identify 5 key current gaps in scientific understanding. We conclude that subsoils, while highly heterogeneous, are in many cases more suited to long-term C sequestration than topsoils. The proposed strategies may also bring other tangible benefits to cropping systems (e.g. enhanced water holding capacity and nutrient use efficiency). Furthermore, while the subsoil C sequestration strategies we reviewed have large potential, more long-term studies are needed across a diverse range of soils and climates, in conjunction with chronosequence and space-for-time substitutions. Also, it is vital that subsoils are more consistently included in modelled estimations of soil C stocks and C sequestration potential, and that subsoil-explicit C models are developed to specifically reflect subsoil processes. Finally, further mapping of subsoil C is needed in specific regions (e.g. in the Middle East, Eastern Europe, South and Central America, South Asia and Africa). Conducting both immediate and long-term subsoil C studies will fill the knowledge gaps to devise appropriate soil C sequestration strategies and policies to help in the global fight against climate change and decline in soil quality. In conclusion, our evidence-based analysis reveals that subsoils offer an untapped potential to enhance global C storage in terrestrial ecosystems
Evaluation of the Effect of a Combined Chemical and Thermal Modification of Wood though the Use of Bicine and Tricine
Get PDFThe effects of thermal modification of wood have been well established, particularly in terms of reductions in mechanical performance. In recent years, there has been an increase in studies related to the Maillard reaction. More commonly associated with food chemistry, it involves the reaction of amines and reducing sugars during cooking procedures. This study has attempted to combine the use of amines and thermal modification, with subsequent properties investigated for the treatment of spruce (Picea abies (L.) H. Karst) and beech (Fagus sylvatica L.). In this initial study, the combined effects of chemical treatments by tricine and bicine were investigated with thermal modification. Along with some preliminary data on mechanical properties, the modifications which appeared in the wood structure were evaluated by infrared spectroscopy and biological studies according to EN113 and EN117 methodologies. The hierarchal study interpretation of FTIR suggested interactions between the bicine or tricine and the wood, which was partly supported by the analysis of volatile organic compounds (VOC), though other tests were not as conclusive. The potential of the method warrants further consideration, which will be described
Tree diversity effects on soil microbial biomass and respiration are context dependent across forest diversity experiments
Get PDFSoil microorganisms are essential for the functioning of terrestrial ecosystems. Although soil microbial communities and functions are linked to tree species composition and diversity, there has been no comprehensive study of how general or context-dependent these relationships are. Here, we examine tree diversity–soil microbial biomass and respiration relationships across environmental gradients using a global network of tree diversity experiments.Soil samples collected from eleven tree diversity experiments were used to measure microbial respiration, biomass, and respiratory quotient using the substrate-induced respiration method. All samples were measured using the same analytical device, method, and procedure to reduce measurement bias. We used linear mixed-effects models and principal component analysis (PCA) to examine the effects of tree diversity (taxonomic and phylogenetic), environmental conditions, and interactions on soil microbial properties. Abiotic drivers, mainly soil water content, but also soil carbon and soil pH, significantly increased soil microbial biomass and respiration. High soil water content reduced the importance of other abiotic drivers. Tree diversity had no effect on the soil microbial properties, but interactions with phylogenetic diversity indicated that diversity effects are context-dependent and stronger in drier soils. Similar results were found for soil carbon and soil pH. Our results point to the importance of abiotic variables, and especially soil water content, for maintaining high levels of soil microbial functions and modulating the effects of other environmental drivers. Planting tree species with diverse water-use strategies and structurally complex canopies and high leaf area may be crucial for maintaining high soil microbial biomass and respiration. Since higher phylogenetic distance alleviated unfavorable soil water conditions, reforestation efforts accounting for traits improving soil water content or choosing more phylogenetically distant species may assist in increasing soil microbial functions
Combining targeted grass traits with red clover improves grassland performance and reduces need for nitrogen fertilisation
Get PDFTo increase ruminant production efficiency, the environmental impact of growing forage must be reduced, through lowering system inputs and increasing crop resilience to extreme weather. Here we examined the role of red clover (cv. AberClaret) in minimising nitrogen (N) requirements, alongside two novel grass varieties, (1) a festulolium (cv. AberNiche), developed for drought tolerance, with potential for deep-rooting, and (2) a ryegrass hybrid (cv. AberEcho), developed for high-sugar content, which may enhance ruminant N-uptake in-vivo. Field trials were conducted at two UK sites, growing festulolium and ryegrass ± red clover (at 29% of the seed mix weight) at a range of N fertilisation rates (0 – 600 kg N ha−1) for 2 years (six harvests). We assessed sward performance (N offtake, herbage quality, and grass N use efficiency), rooting depth and N transfer from clover to grasses using 15N natural abundance. Across both sites and years, dry matter yield and herbage-N content were overall greater from the swards that included clover. Dry matter yields from festulolium were not greater than from ryegrass under the drought conditions experienced in 2018, despite its greater root mass. Agronomic efficiency of fertiliser N was similar between grasses (19 – 22%), however the festulolium more effectively used endogenous soil N than the ryegrass. Inclusion of clover in the sward affected forage quality, with increased crude protein and metabolisable energy content and reduced sugar and fibre (NDF) content. Among the grass types, metabolisable energy was greater and NDF content less for ryegrass than for festulolium. A strong reliance on biological N fixation (80 – 94%) for clover was observed, however, N transfer from clover to the neighbouring grass was not evident from the ẟ15N signatures. We conclude that red clover is a viable fertiliser-N replacement strategy in short-term leys, and that grass varieties with improved herbage quality may provide a better option for optimising sward performance than drought tolerant grass varieties
Dementia Care Mapping. National Strategy
Get PDFThis strategy represents a commitment that all people living with dementia should experience care, which is person-centred, safe and supports their well-being when using care services in Wales. Dementia Care Mapping (DCM) in Wales must be used to understand the experience of care from the perspective of people living with dementia and to inform positive actions to promote person-centred approaches
Turbulence and Coherent Structure Characterisation in a Tidally Energetic Channel
Get PDFUnderstanding the temporal and spatial characteristics of turbulent coherentstructures is of interest to the emergent sector of marine renewable energy forpower generation from tidal stream turbines as loading due to these vortexstructures has resulted in costly device failure. Here methods for characteris-ing these coherent structures are developed using an off the shelf broadbandacoustic Doppler current profiler (ADCP) vertical beam with the metrics fastFourier transforms and a wavelet element model. Results indicate length-scales fall in the range 2.5 to 51 m. Focused study on a 30-minute windowfinds the 5 most powerful features have a median lengthscale of 13.2 m andthe strongest signal lies at ∼6.8 m, which scale to 0.9 and 0.4 times the waterdepth respectively, these features have a periodicity of ∼127 s. Methods us-ing variance across ADCP beams are common for turbulence characterisationwithin the tidal energy sector, with turbulence intensity being appropriatedfrom the wind energy sector. However, turbulence intensity is found to be a poor predictor water column turbulence in the presence of coherent struc-tures.Keywords: Hydrodynamics, Tidal stream turbines, Coherent Structures,Tidal Power, Variance Method, Alternative Energy Site Assessmen
Developing Theoretically Informed Typologies in International Business: Why We Need Them, and How to Do It
Get PDFIn this article, we make the case for theoretically/logically derived explanatory typologies and their constituent ideal types, arguing that they can provide us with the basis to further understand dynamic and complex contemporary phenomena. We contrast this approach with dominant analytical strategies in international-business research. We show that the greater use of explanatory typologies and their associated ideal types in international-business research facilitates comparisons of similar cases; illuminates key, but relatively under-researched aspects of phenomenon; promotes theory building; and readily supports configurational analyses. By doing this, explanatory typologies can underpin rigorous analyses, and enhance the relevance of research findings on causally complex contemporary phenomena at different analytical levels
Changes in microbial community composition drive the response of ecosystem multifunctionality to elevated ozone
Get PDFIncreasing tropospheric ozone poses a potential threat to both above- and belowground components of the terrestrial biosphere. Microorganisms are the main drivers of soil ecological processes, however, the link between soil microbial communities and ecological functions under elevated ozone remains poorly understood. In this study, we assessed the responses of three crop seedlings (i.e., soybean, maize, and wheat) growth and soil microbial communities to elevated ozone (40 ppb O3 above ambient air) in a pot experiment in the solardomes. Results showed that elevated ozone adversely affected ecosystem multifunctionality by reducing crop biomass, inhibiting soil extracellular enzyme activities, and altering nutrient availability. Elevated ozone increased bacterial and fungal co-occurrence network complexity, negatively correlated with ecosystem multifunctionality. Changes in the relative abundance of some specific bacteria and fungi were associated with multiple ecosystem functioning. In addition, elevated ozone significantly affected fungal community composition but not bacterial community composition and microbial alpha-diversity. Crop type played a key role in determining bacterial alpha-diversity and microbial community composition. In conclusion, our findings suggest that short-term elevated ozone could lead to a decrease in ecosystem multifunctionality associated with changes in the complexity of microbial networks in soils
Eugen Ehrlich und die heutige Rechtssoziologie – 10 Thesen
No full textThe paper introduces 10 theses how Ehrlich (1822-1922) is still relevant for today's sociology of law. It starts with Ehrlich showing a social science approach to law, continues with Ehrlich opening up a qualitative empirical approach and suggesting an empirically comparative approach. His work encourages studying legal dogmatic and the tools jurists use. Ehrlich invites to study the development and origins of laws and he sharpens the view on the everyday and the ordered lives of lay people. The emotional grounding of law has been highlighted by Ehrlich as well as conducting research together with students and practitioners. He exemplifies how political perspectives influence research questions and his life reminds of the existential vulnerability of the individual in modern society