bluuebunny/crossref_metadata_2025_split huggingface dataset:
Skin toxicology and 3Rs—Current challenges for public health protection
Authors: Riebeling Christian , Luch Andreas , Tralau Tewes 
Published: March 2018

AbstractDriven by the fast paced development of complex test systems in vitro, mass spectrometry and omics, we finally have the tools to unravel the molecular events that underlie toxicological adversity. Yet, timely regulatory adaptation of these new tools continues to pose major challenges even for organs readily accessible such as skin. The reasons for this encompass a need for conservatism as well as the need of tests to serve an existing regulatory framework rather than to produce scientific knowledge. It is important to be aware of this in order to align regulatory skin toxicity with the 3R principles more readily. While most chemical safety testing is still based on animal data, regulatory frameworks have seen a strong push towards non‐animal approaches. The endpoints corrosion, irritation, sensitisation, absorption and phototoxicity, for example, can now be covered in vitro with the corresponding test guidelines (TGs) being made available by the OECD. However, in vitro approaches tend to be more reductionist. Hence, a combination of several tests is usually preferable to achieve satisfying predictivity. Moreover, the test systems and their combined use need to be standardised and are therefore subject not only to validation but also to the ongoing development of so‐called integrated approaches to testing and assessment (IATAs). Concomitantly, skin models are being refined to deliver the complexity required for increased applicability and predictivity. Given the importance of regulatory applicability for 3R‐derived approaches to have a long‐lasting impact, this review examines the state of regulatory implementation and perspectives, respectively.
The failed implementation of performance management in Irish central government
Authors: McGeough Francis , Beck Matthias 
Published: March 2018

AbstractIreland's Strategic Management Initiative was launched in 1994 and aimed to improve public services delivery. In line with public sector reforms in other countries, it placed strong emphasis on performance management in public sector organisations. Initiatives stressed the need for strategic planning and performance monitoring. The overall impact of these reforms was disappointing, with the Organisation for Economic Co‐operation and Development reporting in 2008 that the Irish public sector lacked a performance culture. This paper utilizes a series of interviews with senior managers in order to identify why performance management did not gain traction and our contribution highlights the complex contextual factors which undermined this agenda.
The development of the management accountant's role revisited: An example from the Swedish Social Insurance Agency
Authors: Holmgren Caicedo Mikael , Mårtensson Maria , Tamm Hallström Kristina 
Published: March 2018

AbstractThis study traces the development of the management accountant (MA) role at the Swedish Social Insurance Agency (SIA). In 2012, the agency began a reformation by implementing the Lean management system in hopes of increasing customer trust. The results of this study show that the authority of the MA rests on decentralization and the proximity of MAs to managers, as previous research has shown, and more specifically on a definitional and a moral prerogative that may or may not be awarded to MAs enabling them to act as de facto managers. The study shows how the role of the SIA's operative level MAs changed into a helpdesk function with the role of assisting other groups to help themselves, in this case operative‐level teams that had begun performing management accounting tasks. Thus, this study bears witness not to the expansion and hybridization of existing MA roles, but to the reduction in authority and de‐hybridization of the MA role, from business partner to a pedagogical role on a consultative basis.
Climate change alters fish community size‐structure, requiring adaptive policy targets
Authors: Queirós Ana M , Fernandes José , Genevier Lily , Lynam Christopher P 
Published: March 2018

AbstractSize‐based indicators are used worldwide in research that supports the management of commercially exploited wild fish populations, because of their responsiveness to fishing pressure. Observational and experimental data, however, have highlighted the deeply rooted links between fish size and environmental conditions that can drive additional, interannual changes in these indicators. Here, we have used biogeochemical and mechanistic niche modelling of commercially exploited demersal fish species to project time series to the end of the 21st century for one such indicator, the large fish indicator (LFI), under global CO2 emissions scenarios. Our modelling results, validated against survey data, suggest that the LFI's previously proposed policy target may be unachievable under future climate change. In turn, our results help to identify what may be achievable policy targets for demersal fish communities experiencing climate change. While fisheries modelling has grown as a science, climate change modelling is seldom used specifically to address policy aims. Studies such as this one can, however, enable a more sustainable exploitation of marine food resources under changes unmanageable by fisheries control. Indeed, such studies can be used to aid resilient policy target setting by taking into account climate‐driven effects on fish community size‐structure.
Structural and functional characterisation of multi‐copper oxidase CueO from lignin‐degrading bacterium Ochrobactrum sp. reveal its activity towards lignin model compounds and lignosulfonate
Authors: Granja‐Travez Rommel Santiago , Wilkinson Rachael C. , Persinoti Gabriela Felix , Squina Fabio M. , Fülöp Vilmos , Bugg Timothy D. H. 
Published: March 2018

The identification of enzymes responsible for oxidation of lignin in lignin‐degrading bacteria is of interest for biotechnological valorization of lignin to renewable chemical products. The genome sequences of two lignin‐degrading bacteria, Ochrobactrum sp., and Paenibacillus sp., contain no B‐type DyP peroxidases implicated in lignin degradation in other bacteria, but contain putative multicopper oxidase genes. Multi‐copper oxidase CueO from Ochrobactrum sp. was expressed and reconstituted as a recombinant laccase‐like enzyme, and kinetically characterized. Ochrobactrum CueO shows activity for oxidation of β‐aryl ether and biphenyl lignin dimer model compounds, generating oxidized dimeric products, and shows activity for oxidation of Ca‐lignosulfonate, generating vanillic acid as a low molecular weight product. The crystal structure of Ochrobactrum CueO (OcCueO) has been determined at 1.1 Å resolution (PDB: 6EVG), showing a four‐coordinate mononuclear type I copper center with ligands His495, His434 and Cys490 with Met500 as an axial ligand, similar to that of Escherichia coli CueO and bacterial azurin proteins, whereas fungal laccase enzymes contain a three‐coordinate type I copper metal center. A trinuclear type 2/3 copper cluster was modeled into the active site, showing similar structure to E. coli CueO and fungal laccases, and three solvent channels leading to the active site. Site‐directed mutagenesis was carried out on amino acid residues found in the solvent channels, indicating the importance for residues Asp102, Gly103, Arg221, Arg223, and Asp462 for catalytic activity. The work identifies a new bacterial multicopper enzyme with activity for lignin oxidation, and implicates a role for bacterial laccase‐like multicopper oxidases in some lignin‐degrading bacteria.DatabaseStructural data are available in the PDB under the accession number 6EVG.
Interaction of isolated cross‐linked short actin oligomers with the skeletal muscle myosin motor domain
Authors: Qu Zheng , Fujita‐Becker Setsuko , Ballweber Edda , Ince Semra , Herrmann Christian , Schröder Rasmus R. , Mannherz Hans Georg 
Published: March 2018

The cyclical interaction between F‐actin and myosin in muscle cells generates contractile force. The myosin motor domain hydrolyses ATP, resulting in conformational changes that are amplified by the myosin lever arm that links the motor domain to the rod domain. Recent cryo‐electron microscopic data have provided a clear picture of the myosin‐ATP–F‐actin complex, but structural insights into other stages of the myosin‐actin interaction have been less forthcoming. To address this issue, we cross‐linked F‐actin subunits between Cys374 and Lys191, and separated them by gel filtration. Purified actin‐dimers, ‐trimers and ‐tetramers retained the ability to polymerize and to stimulate myosin‐subfragment 1 (myosin‐S1) ATPase activity. To generate stable actin oligomer:myosin‐S1 complexes, we blocked actin polymerization with gelsolin and Clostridium botulinum iota toxin‐mediated ADP‐ribosylation. After polymerization inhibition, actin‐trimers and ‐tetramers retained the ability to stimulate the myosin‐S1‐ATPase, whereas the actin‐dimer showed very little ATPase stimulation. We then analysed the stoichiometry and binding affinity of myosin‐S1 to actin oligomers. Actin‐trimers and ‐tetramers bound myosin‐S1 in the absence of nucleotide; the trimer contains one myosin‐S1 binding site. We calculated a dissociation constant (Kd) of 1.1 × 10−10 m and 1.9 × 10−10 m for binding of native F‐actin and the actin‐trimer to myosin‐S1, respectively. EM of the actin‐trimer:myosin‐S1 complex demonstrated the presence of single particles of uniform size. Image reconstruction allowed a reasonable fit of the actin‐trimer and myosin‐S1 into the obtained density clearly showing binding of one myosin‐S1 molecule to the two long‐pitch actins of the trimer, supporting the kinetic data.
On the connection between Palmgren‐Miner rule and crack propagation laws
Authors: Ciavarella M. , D'antuono P. , Papangelo A. 
Published: March 2018

AbstractThe classical Palmgren‐Miner (PM) rule, despite clearly approximation, is commonly applied for the case of variable amplitude loading, and to date, there is no simple alternative. In the literature, previous authors have commented that the PM hypothesis is based on an exponential fatigue crack growth law, ie, when da/dN is proportional to the crack size a, the case that includes also Paris law for m=2, in particular. This is because they applied it by updating the damage estimate during the crack growth.It is here shown that applying PM to the “initial” and nominal (Stress vs Number of cycles) curve of a cracked structure results exactly in the integration of the simple Paris power law equation and more in general to any crack law in the form da/dN=HΔσhan. This leads to an interesting new interpretation of PM rule. Indeed, the fact that PM rule is often considered to be quite inaccurate pertains more to the general case when propagation cannot be simplified to this form (like when there are distinct initiation and propagation phases), rather than in long crack propagation. Indeed, results from well‐known round‐robin experiments under spectrum loading confirm that even using modified Paris laws for crack propagation, the results of the “noninteraction” models, neglecting retardation and other crack closure or plasticity effects due to overloads, are quite satisfactory, and these correspond indeed very closely to applying PM, at least when geometrical factors can be neglected. The use of generalized exponential crack growth, even in the context of spectrum loading, seems to imply the PM rule applies. Therefore, this seems closely related to the so‐called lead crack fatigue lifing framework. The connection means however that the same sort of accuracy is expected from PM rule and from assuming exponential crack growth for the entire lifetime.
Acoustic monitoring reveals diversity and surprising dynamics in tropical freshwater soundscapes
Authors: Gottesman Benjamin L. , Francomano Dante , Zhao Zhao , Bellisario Kristen , Ghadiri Maryam , Broadhead Taylor , Gasc Amandine , Pijanowski Bryan C. 
Published: March 2018

Abstract

Freshwater systems are globally threatened and in need of enhanced monitoring and assessment. We applied soundscape recording and analysis—which presents an opportunity for long‐term, high‐resolution animal community monitoring and assessment—to a freshwater context to better understand the acoustic diversity and dynamics of these systems.

We recorded the aquatic soundscape of a Neotropical freshwater swamp in Costa Rica for 23 days in January and February 2015 during the dry season. We classified biological sound types in these recordings and developed measurements of richness and occupancy based on this classification. We also calculated six complementary acoustic indices to assess soundscape diversity and daily and longer‐term soundscape dynamics, and we examined correlations between these acoustic indices and sound type metrics.

We found rich soundscapes in which biological sounds were almost always present, and we classified 18 sound types that we attribute to aquatic insects. These sound types showed distinct daily patterns and exhibited temporal and spectral acoustic niche partitioning. Sound type richness was most correlated with the number of peaks index (correlation = .36; p < .001), while sound type occupancy was most correlated with the Bioacoustic Index (correlation = .92; p < .001). In contrast to generally high levels of acoustic activity, there were brief (approximately 1 hr), unexpected quiet periods around dawn and dusk.

This study represents an early attempt to comprehensively describe tropical freshwater soundscapes in a systematic and quantitative manner. We demonstrate that sound type classification and the quantification of acoustic occupancy capture aspects of soundscape diversity and dynamics that are complementary to those assessed by acoustic indices. Our analyses reveal that the soundscapes of this tropical wetland were diverse and exhibited daily dynamics that differed from those found in other ecosystems.
Evaluating effects of weed cutting on water level and ecological status in Danish lowland streams
Authors: Baattrup‐Pedersen Annette , Ovesen Niels B. , Larsen Søren E. , Andersen Dagmar K. , Riis Tenna , Kronvang Brian , Rasmussen Jes J. 
Published: March 2018

AbstractAt present, scientific evidence documenting effects of weed cutting in streams as a measure to improve flood protection and run‐off from agricultural land is scarce, which is surprising considering the huge effect that it has on stream ecology. Instead, weed cutting is performed under the assumption that removal of aquatic plant biomass improves runoff from agricultural land and prevents flooding of adjacent areas provided that it is performed regularly.In this study, we examined linkages between weed cutting practice and water level reductions in 126 small‐ and medium‐sized Danish streams (catchment size <100 km2) with continuously monitored discharge and water level data (from 1990 to 2012). Specifically, we hypothesised that (1) weed cutting reduces stream water levels more in late summer when the biomass of aquatic plants is higher than in early summer; (2) the efficiency of cutting declines with increasing cutting frequency as the aquatic plant community changes with increasing abundance of species able to regrow fast following a cutting event; (3) the high‐frequency cutting in Danish streams lowers the ecological status of the streams as evaluated from aquatic plant assemblages.The average effect of weed cutting on the water level was largest in July, August and September with an average reduction of 16 cm and lowest in early spring and late autumn with an average reduction of 11 cm. Regrowth was largest in June, with an increase in water level of 0.41 cm/day, whereas regrowth was absent in autumn. Regrowth also varied with the frequency of weed cutting, from an average of 0.04 cm/day in streams subjected to one annual cutting to an average of 0.6 cm/day in streams subjected to >6 annual cuttings. Furthermore, we found that the ecological status was either moderate or poor/bad in streams with more than one annual cutting.Our findings highlight that it is by no means certain that the current weed cutting practice is efficient for flood control since (1) regrowth is stimulated by frequent cuttings and a positive feedback loop may develop, necessitating even more frequent cuttings to maintain the discharge capacity of the streams, and (2) many species stimulated by weed cutting, like for instanceSparganium emersum, form dense canopy beds across the entire stream profile and therefore reduce the discharge capacity of the stream more than species growing in confined patches. We encourage more studies with the aim to identify how stream maintenance should be performed to optimise flood control without compromising the ability to reach good ecological stream quality.
Emerging threat of the 21st century lightscape to global biodiversity
Authors: Koen Erin L. , Minnaar Corneile , Roever Carrie L. , Boyles Justin G. 
Published: March 2018

AbstractOver the last century the temporal and spatial distribution of light on Earth has been drastically altered by human activity. Despite mounting evidence of detrimental effects of light pollution on organisms and their trophic interactions, the extent to which light pollution threatens biodiversity on a global scale remains unclear. We assessed the spatial extent and magnitude of light encroachment by measuring change in the extent of light using satellite imagery from 1992 to 2012 relative to species richness for terrestrial and freshwater mammals, birds, reptiles, and amphibians. The encroachment of light into previously dark areas was consistently high, often doubling, in areas of high species richness for all four groups. This pattern persisted for nocturnal groups (e.g., bats, owls, and geckos) and species considered vulnerable to extinction. Areas with high species richness and large increases in light extent were clustered within newly industrialized regions where expansion of light is likely to continue unabated unless we act to conserve remaining darkness. Implementing change at a global scale requires global public, and therefore scientific, support. Here, we offer substantial evidence that light extent is increasing where biodiversity is high, representing an emerging threat to global biodiversity requiring immediate attention.
Global effects of plant litter alterations on soil CO2 to the atmosphere
Authors: Chen Xinli , Chen Han Y. H. 
Published: March 2018

AbstractSoil respiration (Rs) is the largest terrestrial carbon (C) efflux to the atmosphere and is predicted to increase drastically through global warming. However, the responses of Rs to global warming are complicated by the fact that terrestrial plant growth and the subsequent input of plant litter to soil are also altered by ongoing climate change and human activities. Despite a number of experiments established in various ecosystems around the world, it remains a challenge to predict the magnitude and direction of changes in Rs and its temperature sensitivity (Q10) due to litter alteration. We present a meta‐analysis of 100 published studies to examine the responses of Rs and Q10 to manipulated aboveground and belowground litter alterations. We found that 100% aboveground litter addition (double litter) increased Rs by 26.1% (95% confident intervals, 18.4%–33.7%), whereas 100% aboveground litter removal, root removal and litter + root removal reduced Rs by 22.8% (18.5%–27.1%), 34.1% (27.2%–40.9%) and 43.4% (36.6%–50.2%) respectively. Moreover, the effects of aboveground double litter and litter removal on Rs increased with experimental duration, but not those of root removal. Aboveground litter removal marginally increased Q10 by 6.2% (0.2%–12.3%) because of the higher temperature sensitivity of stable C substrate than fresh litter. Estimated from the studies that simultaneously tested the responses of Rs to aboveground litter addition and removal and assuming negligible changes in root‐derived Rs, “priming effect” on average accounted for 7.3% (0.6%–14.0%) of Rs and increased over time. Across the global variation in terrestrial ecosystems, the effects of aboveground litter removal, root removal, litter + root removal on Rs as well as the positive effect of litter removal on Q10 increased with water availability. Our meta‐analysis indicates that priming effects should be considered in predicting Rs to climate change‐induced increases in litterfall. Our analysis also highlights the need to incorporate spatial climate gradient in projecting long‐term Rs responses to litter alterations.
Nitrogen fertilization raises CO2 efflux from inorganic carbon: A global assessment
Authors: Zamanian Kazem , Zarebanadkouki Mohsen , Kuzyakov Yakov 
Published: March 2018

AbstractNitrogen (N) fertilization is an indispensable agricultural practice worldwide, serving the survival of half of the global population. Nitrogen transformation (e.g., nitrification) in soil as well as plant N uptake releases protons and increases soil acidification. Neutralizing this acidity in carbonate‐containing soils (7.49 × 109 ha; ca. 54% of the global land surface area) leads to a CO2 release corresponding to 0.21 kg C per kg of applied N. We here for the first time raise this problem of acidification of carbonate‐containing soils and assess the global CO2 release from pedogenic and geogenic carbonates in the upper 1 m soil depth. Based on a global N‐fertilization map and the distribution of soils containing CaCO3, we calculated the CO2 amount released annually from the acidification of such soils to be 7.48 × 1012 g C/year. This level of continuous CO2 release will remain constant at least until soils are fertilized by N. Moreover, we estimated that about 273 × 1012 g CO2‐C are released annually in the same process of CaCO3 neutralization but involving liming of acid soils. These two CO2 sources correspond to 3% of global CO2 emissions by fossil fuel combustion or 30% of CO2 by land‐use changes. Importantly, the duration of CO2 release after land‐use changes usually lasts only 1–3 decades before a new C equilibrium is reached in soil. In contrast, the CO2 released by CaCO3 acidification cannot reach equilibrium, as long as N fertilizer is applied until it becomes completely neutralized. As the CaCO3 amounts in soils, if present, are nearly unlimited, their complete dissolution and CO2 release will take centuries or even millennia. This emphasizes the necessity of preventing soil acidification in N‐fertilized soils as an effective strategy to inhibit millennia of CO2 efflux to the atmosphere. Hence, N fertilization should be strictly calculated based on plant‐demand, and overfertilization should be avoided not only because N is a source of local and regional eutrophication, but also because of the continuous CO2 release by global acidification.