Fuel cells for power generation and organic waste treatment on the island of Mull

In-situ use of biomass and organic waste streams have the potential to provide the key to energy self sustainability for islands and remote communities. Traditionally biogas fuels have been used in combustion engines for electric power generation. However, fuel cells offer the prospect of achieving higher generating efficiencies, and additionally, important environmental benefits can be achieved by way of mitigating greenhouse gas emissions, whilst providing a carbon sink. This paper presents the design details of a biogas gas plant and fuel cell installation that will provide a practical solution on an island (and be applicable in other remote and rural areas) where connection to the grid can be expensive, and where biofuels can be produced on site at no significant extra cost

Prediction of Nitrogen Inputs for Sugar Beet.An Evaluation of Soil Tests and Soil

End of Project ReportCurrently, advice on nitrogen (N) use for tillage crops employs an index system based on crop management. However, there has not been a systematic evaluation of several of its components or of the relevance of soil tests, alone or in conjunction. The objective of the current study, therefore, was to evaluate relevant soil management data, various biological and chemical soil tests, and measurements of Nmin (NH4 + NO3) in the root profile, for prediction of fertiliser N requirements. The data used in the study were derived from a data bank of results of field and laboratory experiments for sugar beet. The following topics were addressed: selection of regression models based on soil management criteria; sustainability of contribution of soil N reserves; limitations of soil tests for N; long-term trends in Nmin and biomass C; relationship of mineral-N flush with biomass C; relevance of Nmin with growing-season rainfall; implications of winter rainfall for residual effects and their justification within the current soil N index.European Union Structural Funding (EAGGF

Dynamics of quantum-dot mode-locked lasers with optical injection

We present the dynamics of quantum-dot passively mode-locked semiconductor lasers under optical injection. We discuss the benefits of various configurations of the master source including single, dual, and multiple coherent frequency sources. In particular, we demonstrate that optical injection can improve the properties of the slave laser in terms of time-bandwidth product, optical linewidth, and timing jitter

Two-photon-induced photoconductivity enhancement in semiconductor microcavities: a theoretical investigation

We describe a detailed theoretical investigation of two-photon absorption photoconductivity in semiconductor microcavities. We show that high enhancement (by a factor of >10, 000) of the nonlinear response can be obtained as a result of the microcavity effect. We discuss in detail the design and performance (dynamic range, speed) of such a device with the help of the example of an AlGaAs/GaAs microcavity operating at 900 nm. This device shows promise for low-intensity, fast autocorrelation and demultiplexing applications

Wider-frequency combs generation, noise reduction, and repetition rate tuning in quantum-dot mode-locked lasers

We describe the technique allowing for generation of low-noise wider frequency combs and pulses of shorter duration in quantum-dot mode-locked lasers. We compare experimentally noise stabilization techniques in semiconductor modelocked lasers. We discuss the benefits of electrical modulation of the laser absorber voltage (hybrid mode-locking), combination of hybrid mode-locking with optical injection seeding from the narrow linewidth continues wave master source and optical injection seeding of two coherent sidebands separated by the laser repetition rate

What support do frontline workers want? A qualitative study of health and social care workers' experiences and views of psychosocial support during the COVID-19 pandemic

Background: The COVID-19 pandemic has placed a significant burden on the mental health and wellbeing of frontline health and social care workers. The need to support frontline staff has been recognised. However, there is to date little research specifically on how best to support the mental health needs of frontline workers, and none on their own experiences and views about what might be most helpful. Aims: We set out to redress this research gap by qualitatively exploring UK frontline health and social care workers’ own experiences and views of psychosocial support during the pandemic. Method: Frontline health and social care workers were recruited purposively through social media and by snowball sampling via healthcare colleagues. Workers who volunteered to take part in the study were interviewed remotely following a semi-structured interview guide. Transcripts of the interviews were analysed by the research team following the principles of Reflexive Thematic Analysis. Results: We conducted 25 interviews with frontline workers from a variety of professional groups working in health and social care settings across the UK. Themes derived from our analysis showed that workers’ experiences and views about psychosocial support were complex. Peer support was many workers’ first line of support but could also be experienced as a burden. Workers were ambivalent about support shown by organisations, media and the public. Whilst workers valued psychological support services, there were many disparities in provision and barriers to access. Conclusions: The results of this study show that frontline health and social care workers are likely to need a flexible system of support including peer, organisational and professional support. More research is needed to fully unpack the structural, systemic and individual barriers to accessing psychosocial support. Greater collaboration, consultation and co-production of support services and their evaluation is warranted

Optimisation of a Multi-Gravity Separator with Novel Modifications for the Recovery of Ferberite

This is the final version of the article. Available from MDPI via the DOI in this record.Tungsten is considered by the European Union as a critical raw material for future development due to its expected demand and scarcity of resource within Europe. It is therefore, critical to optimize European tungsten operations and maximise recoveries. The role of enhanced gravity/centrifugal concentrators in recovering tungsten from ultra-fine fractions should form an important part of this aim. Reported herein are the results of investigations to improve efficiency of Wolf Minerals’ Draklends mine, a major European tungsten mine, by recovering saleable material from a magnetic waste stream of a low-intensity magnetic separator using an enhanced gravity concentrator. The mine hosts wolframite and ferberite as the main tungsten bearing mineral species. A Mozley multi-gravity separator (MGS) C-900 was selected as it is suited to exploiting small variations in mineral density to affect a separation. Working with a current manufacturer, a novel scraping blade system was tested. To assess the MGS in a statistically valid manner, a response surface methodology was followed to determine optimal test conditions. The test programme showed that the most important parameters were drum speed and wash water rate. Under optimal conditions the model predicted that 40% of the tungsten could be recovered above the required grade of 43% WO3.This work is part of the OptimOre project. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 642201. Authors are thankful to Wolf Minerals for providing material for experimentation and to Gravity Mining Ltd. for support in undertaking experiments and providing the opportunity to test the modified low profile blades

Synthesis of alpha-amino acid derived (1,2,3-triazol-4-yl)-picolinamide (tzpa) ligands and their corresponding luminescent Tb(iii) complexes

The synthesis of chiral a-amino acid derived (1,2,3-triazol-4-yl)-picolinamide (tzpa) ligands 4-6 designed by combining the coordination properties of two well-known ligand structures within a single unit is described. The self-assembly formation between these ligands and the lanthanide ion Tb(iii) was investigated in solution by probing the ground and the singlet excited state properties of the ligands as well as monitoring the evolution of the Tb(iii) emission at long wavelengths. The spectroscopic results showed that while under thermodynamic control the 1 : 3 (Tb : L) is produced, then analysis of the titration data using non-liner regression analysis demonstrated that the main species in solution is the 1 : 2 (Tb : L) after the addition of 0.5 equivalents of Tb(iii)

Bistability and hysteresis in an optically injected two-section semiconductor laser

The effect of coherent single frequency injection on two-section semiconductor lasers is studied numerically using a model based on a set of delay differential equations. The existence of bistability between different continuous-wave and nonstationary regimes of operation is demonstrated in the case of sufficiently large linewidth enhancement factors

Interaction of preimplantation factor with the global bovine endometrial transcriptome

Preimplantation factor (PIF) is an embryo derived peptide which exerts an immune modulatory effect on human endometrium, promoting immune tolerance to the embryo whilst maintaining the immune response to invading pathogens. While bovine embryos secrete PIF, the effect on the bovine endometrium is unknown. Maternal recognition of pregnancy is driven by an embryo-maternal cross talk, however the process differs between humans and cattle. As many embryos are lost during the early part of pregnancy in cattle, a greater knowledge of factors affecting the embryo-maternal crosstalk, such as PIF, is needed to improve fertility. Therefore, for the first time, we demonstrate the effect of synthetic PIF (sPIF) on the bovine transcriptome in an ex vivo bovine endometrial tissue culture model. Explants were cultured for 30h with sPIF (100nM) or in control media. Total RNA was analysed via RNA-sequencing. As a result of sPIF treatment, 102 genes were differentially expressed compared to the control (Padj<0.1), although none by more than 2-fold. The majority of genes (78) were downregulated. Pathway analysis revealed targeting of several immune based pathways. Genes for the TNF, NF-κB, IL-17, MAPK and TLR signalling pathways were down-regulated by sPIF. However, some immune genes were demonstrated to be upregulated following sPIF treatment, including C3. Steroid biosynthesis was the only over-represented pathway with all genes upregulated. We demonstrate that sPIF can modulate the bovine endometrial transcriptome in an immune modulatory manner, like that in the human endometrium, however, the regulation of genes was much weaker than in previous human work