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Building, bridge or wind turbine maintenance requires manual dexterity tasks by a specialist rope-access trained workforce via two principal means: harness suspension of individual workers from above, or deployment of a suspended platform or cradle from which workers access the structure to be maintained. Currently no published research compares accuracy and efficiency of simulated maintenance tasks between these modalities. This study investigated manual dexterity task performance of peg placement and shape delineation in seated, standing and suspended environments in 16 healthy controls and 26 professional rope-access trained individuals. Both seated and standing assessments were superior to those suspended, and height of suspension, total mass and years of experience had no influence on the task outcome. These findings suggest that, where feasible, cradle suspension mechanisms which permit standing maintenance are favourable in terms of task efficacy and where feasible, should be considered for deployment in wind energy and other engineering applications.

Previous studies reveal that the primary distribution of the current density is sharply enhanced at the edge of a disk electrode submerged into a semi-infinite space of conductive solution. The current enhancement will cause the double layer capacitance at the periphery of the electrode to be charged much faster compared to the center, and can also lead to severe corrosion at the edge. While several studies focused on the geometric design of the electrode to reduce this enhancement, we explore the feasibility of achieving similar effect by shaping the edges of the current input. The simulation uses finite element analysis software to solve the system of partial differential equations and results show that the edge enhancement could be greatly reduced without significantly changing the input efficacy of current and/or charge.

The formation and decay of excited states of light‐harvesting bacteriochlorophyll (BChl) molecules and primary charge separation in reaction centres (RCs) of pigment‐protein complex B890 of the purple bacterium Chromatium minutissimum were studied as a function of excitation wavelength by means of picosecond absorbance difference spectroscopy. Selective excitation in the RC absorption band (at 800 nm) induced rapid bleaching of the absorption band of the RC BChl dimer (τ ∼ 1 ps) without absorption changes due to excited light‐harvesting BChl. It is concluded that excitation energy transfer from the BChl dimer of the RC to light‐harvesting BChl molecules is considerably slower than RC charge separation. Therefore, energy transfer from the light‐harvesting antenna to the RC in bacterial photosynthesis may be described as a ‘migration‐limited model’.

From its inception, the Nuclear Energy Agency (NEA), which is part of the broader Organisation for Economic Co-operation and Development, has contributed to the development of international radiological protection norms and standards. This continues today, in the form of studies and workshops to assist radiological protection policy makers, regulators and practitioners to develop concepts and approaches to help the international system of radiological protection, as recommended by the International Commission on Radiological Protection (ICRP), to evolve to better serve societal needs. The NEA's Committee on Radiation Protection and Public Health (CRPPH), in providing this support, has collaborated closely with the ICRP and strongly supports the current ICRP recommendation development process. In particular, active dialogue with a broad range of stakeholders is contributing to the evolution of concepts towards consensus on new ICRP recommendations. The CRPPH, as a body of ICRP recommendation practitioners, feels that the public, workers and the environment are well protected by the current radiological protection system, but agrees that a new consolidation and clarification of ICRP recommendations would be of value. The intent of the CRPPH in collaborating with ICRP is to develop a system of radiological protection that is simplified, more coherent, firmly based upon science and more clearly presented than the current system. This paper summarises the more detailed views of the CRPPH on the evolution of the system of radiological protection.

A noncompartmented microbial fuel cell (NCMFC) composed of a Mn(IV)-carbon plate and a Fe(III)-carbon plate was used for electricity generation from organic wastewater without consumption of external energy. The Fe(III)-carbon plate, coated with a porous ceramic membrane and a semipermeable cellulose acetate film, was used as a cathode, which substituted for the catholyte and cathode. The Mn(IV)-carbon plate was used as an anode without a membrane or film coating. A solar cell connected to the NCMFC activated electricity generation and bacterial consumption of organic matter contained in the wastewater. More than 99 degrees of the organic matter was biochemically oxidized during wastewater flow through the four NCMFC units. A predominant bacterium isolated from the anode surface in both the conventional and the solar cell-linked NCMFC was found to be more than 99 degrees similar to a Mn(II)-oxidizing bacterium and Burkeholderia sp., based on 16S rDNA sequence analysis. The isolate reacted electrochemically with the Mn(IV)-modified anode and produced electricity in the NCMFC. After 90 days of incubation, a bacterial species that was enriched on the Mn(IV)-modified anode surface in all of the NCMFC units was found to be very similar to the initially isolated predominant species by comparing 16S rDNA sequences.

The fast decay in PEM fuel cells of a highly active, high performance, but unstable Fe/N/C catalyst like our NC_Ar + NH3 follows a chemical, not an electrochemical, demetallation mechanism for its ORR active FeN4 sites in the catalyst micropores.

The increasing demand for lignocellulosic biomass for the production of biofuels provides value to vegetative plant tissue and leads to a paradigm shift for optimizing plant architecture in bioenergy crops. Plant height (PHT) is among the most important biomass yield components and is the focus of this review, with emphasis on the energy grasses maize (Zea mays) and sorghum (Sorghum bicolor). We discuss the scientific advances in the identification of PHT quantitative trait loci (QTLs) and the understanding of pathways and genes controlling PHT, especially gibberellins and brassinosteroids. We consider pleiotropic effects of QTLs or genes affecting PHT on other agronomically important traits and, finally, we discuss strategies for applying this knowledge to the improvement of dual-purpose or dedicated bioenergy crops.

The conceptualization of the Shared Socioeconomic Pathways (SSPs) framework represented a major leap in scenario development in the context of global environmental change and sustainability, providing significant advances from the previous scenario frameworks-especially the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios. It is highly likely that the SSP concept, along with its scenario narratives and their respective results, including land-use change projections, will play a substantial role in the forthcoming Sixth Assessment Report by the IPCC. Here, we offer some insights that could make the SSPs' projected future changes in global land use more comprehensive and also help improve the interpretability of such projections. For example, instead of focusing on the quantity of each land-use class at various time points which results only in a net change when change is detected between time points, we recommend that the projected gross gains and gross losses in each land-use class across all scenarios should also be considered. Overall, the insights presented could also help pave the way for stronger collaboration between the SSP-climate science community and the land system science community; such collaboration is much needed in addressing the challenges of global environmental change towards a climate-resilient sustainable development pathway.