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Brain-derived neurotrophic factor (BDNF), an important neural growth factor, has gained growing interest in neuroscience, but many influencing physiological and analytical aspects still remain unclear. In this study we assessed the impact of storage time at room temperature, repeated freeze/thaw cycles, and storage at 80 C up to 6 months on serum and ethylenediaminetetraacetic acid (EDTA)-plasma BDNF. Furthermore, we assessed correlations of serum and plasma BDNF concentrations in two independent sets of samples. Coefficients of variations (CVs) for serum BDNF concentrations were significantly lower than CVs of plasma concentrations (n = 245, p = 0.006). Mean serum and plasma concentrations at all analyzed time points remained within the acceptable change limit of the inter-assay precision as declared by the manufacturer. Serum and plasma BDNF concentrations correlated positively in both sets of samples and at all analyzed time points of the stability assessment (r = 0.455 to rs = 0.596; p < 0.004). In summary, when considering the acceptable change limit, BDNF was stable in serum and in EDTA-plasma up to 6 months. Due to a higher reliability, we suggest favoring serum over EDTA-plasma for future experiments assessing peripheral BDNF concentrations.

Mainstreaming of ecosystem service approaches has been proposed as one path toward sustainable development. Meanwhile, critics of ecosystem services question if the approach can account for the multiple values of ecosystems to diverse groups of people, or for aspects of inter- and intra-generational justice. In particular, an ecosystem service approach often overlooks power dimensions and capabilities that are core to environmental justice. This article addresses the need for greater guidance on incorporating justice into ecosystem services research and practice. We point to the importance of deep engagement with stakeholders and rights holders to disentangle contextual factors that moderate justice outcomes on ecosystem service attribution and appropriation in socio-political interventions. Such a holistic perspective enables the integration of values and knowledge plurality for enhancing justice in ecosystem services research. This broadened perspective paves a way for transformative ecosystem service assessments, management, and research, which can help inform and design governance structures that nourish human agency to sustainably identify, manage, and enjoy ecosystem services for human wellbeing.

The recent successes in analyzing images with deep neural networks are almost exclusively achieved with Convolutional Neural Networks (CNNs). The training of these CNNs, and in fact of all deep neural network architectures, uses the backpropagation algorithm where the output of the network is compared with the desired result and the difference is then used to tune the weights of the network towards the desired outcome. In a 2022 preprint, Geoffrey Hinton suggested an alternative way of training which passes the desired results together with the images at the input of the network. This so called Forward Forward (FF) algorithm has up to now only been used in fully connected networks. In this paper, we show how the FF paradigm can be extended to CNNs. Our FF-trained CNN, featuring a novel spatially-extended labeling technique, achieves a classification accuracy of 99.16% on the MNIST hand-written digits dataset. We show how different hyperparameters affect the performance of the proposed algorithm and compare the results with CNN trained with the standard backpropagation approach. Furthermore, we use Class Activation Maps to investigate which type of features are learnt by the FF algorithm., Comment: 19 pages, 9 figures

Context. During the post-perihelion phase of the European Space Agency's Rosetta mission to comet 67P, the Optical, Spectroscopic, and Infrared Remote Imaging System on board the spacecraft took numerous image sequences of the near-nucleus coma, with many showing the motion of individual pieces of debris ejected from active surface areas into space. Aims. We aim to track the motion of individual particles in these image sequences and derive their projected velocities and accelerations. This should help us to constrain their point of origin on the surface, understand the forces that influence their dynamics in the inner coma, and predict whether they will fall back to the surface or escape to interplanetary space. Methods. We have developed an algorithm that tracks the motion of particles appearing as point sources in image sequences. Our algorithm employs a point source detection software to locate the particles and then exploits the image sequences' pair-nature to reconstruct the particle tracks and derive the projected velocities and accelerations. We also constrained the particle size from their brightness. Results. Our algorithm identified 2268 tracks in a sample image sequence. Manual inspection not only found that 1187 (~52%) of them are likely genuine, but in combination with runs on simulated data it also revealed a simple criterion related to the completeness of a track to single out a large subset of the genuine tracks without the need for manual intervention. A tentative analysis of a small (n = 89) group of particles exemplifies how our data can be used, and provides first results on the particles' velocity, acceleration, and radius distributions, which agree with previous work., Comment: 16 pages, 20 figures

Global frameworks to guide consistent monitoring of changes in human–nature interactions across space and time are needed to better understand how healthy ecosystems support societies and to inform policy design. Monitoring Essential Ecosystem Service Variables (EESVs) can provide a comprehensive picture of how links between nature and people are changing. A first proposed set of EESV classes comprises: ecological supply, anthropogenic contribution, demand, use, instrumental values, and relational values. Development of specific indicators of these classes for three exemplary ecosystem services (food from fisheries, crop pollination and wildlife viewing) confirms their readiness for global operationalization. The EESV classes will advance our ability to monitor progress towards achieving the Sustainable Development Goals.

Food systems are primary drivers of human and environmental health, but the understanding of their diverse and dynamic co-transformation remains limited. We use a data-driven approach to disentangle different development pathways of national food systems (i.e. ‘transformation archetypes’) based on historical, intertwined trends of food system structure (agricultural inputs and outputs and food trade), and social and environmental outcomes (malnutrition, biosphere integrity, and greenhouse gases emissions) for 161 countries, from 1995 to 2015. We found that whilst agricultural total factor productivity has consistently increased globally, a closer analysis suggests a typology of three transformation archetypes across countries: rapidly expansionist, expansionist, and consolidative. Expansionist and rapidly expansionist archetypes increased in agricultural area, synthetic fertilizer use, and gross agricultural output, which was accompanied by malnutrition, environmental pressures, and lasting socioeconomic disadvantages. The lowest rates of change in key structure metrics were found in the consolidative archetype. Across all transformation archetypes, agricultural greenhouse gases emissions, synthetic fertilizer use, and ecological footprint of consumption increased faster than the expansion of agricultural area, and obesity levels increased more rapidly than undernourishment decreased. The persistence of these unsustainable trajectories occurred independently of improvements in productivity. Our results underscore the importance of quantifying the multiple human and environmental dimensions of food systems transformations and can serve as a starting point to identify potential leverage points for sustainability transformations. More attention is thus warranted to alternative development pathways able of delivering equitable benefits to both productivity and to human and environmental health.

Peer Reviewed

Biosphere reserves (BR) balance biodiversity protection and sustainable use through different management restrictions in three zones: core areas, buffer zones, and transition areas. Information about the links between zoning and ecosystem services (ES) is lacking, particularly in terms of the relative roles of natural contributions (ecosystem properties and functions) and anthropogenic contributions (human inputs such as technology and infrastructure) in coproducing ES. This study aimed to: (1) analyse how coproduction of four ES (crop production, grazing, timber production, recreation) differs across the three zones of BRs; and (2) understand which predictors (zoning, natural and anthropogenic contributions, other environmental characteristics) best explain ES provision within BRs. To do this, we collected spatial data on 137 terrestrial BRs in the European Union and on 16 indicators of ES coproduction. We used non-parametric pairwise Wilcoxon rank sum tests to calculate differences in indicators between zones. We used model selection and multiple linear regression to identify predictors of ES provision patterns. Anthropogenic contributions showed most differences between zones, with contributions generally increasing from buffer zones to transition areas. Natural contributions did not, on average, differ between zones, however, for recreation and crop production they decreased from buffer zones to transition areas. ES provision differed between zones only for crop production and grazing, which increased from buffer zones to transition areas. Regression analysis showed that natural contributions are the best predictors of ES provision for all four services. Our results indicate that zoning of BRs has implications for ES coproduction.

The potential supply of ecosystem services is often assessed using land cover data. Assessment of actual use of ecosystem services by beneficiaries remains less covered and is often assumed to be congruent with potential supply. However, we believe that to contribute to the sustainable management of multifunctional landscapes, more insights are needed on the links between landscape characteristics and the various facets of ecosystem services. In this paper, we assess cultural ecosystem services (CES) such as recreation, inspiration or scenic beauty in three European mountain protected areas and their surroundings. We study the alignment between the potential supply and actual use of CES. CES potential supply was modelled using six biophysical indicators derived from earth observation and open geospatial data. For CES actual use, we employed participatory mapping with protected area visitors and local experts. We modelled CES actual use as a function of landscape biophysical indicators, weighted by (i) stated and (ii) revealed visitor preferences, and accessibility in each protected area using generalized additive mixed-effects models. Accessibility alone could explain around 50% of the variability of CES actual use, and with the additional inclusion of the ‘natural and cultural features’ variable, the actual use models reached an explanatory power of around 80% for all three case-studies. Importantly, biophysical information using land cover data alone cannot fully describe CES actual use, and there was little congruency between modelled potential supply and actual use. Additional socio-cultural features are required to explain the patterns of locations where protected area visitors enjoy CES. Our results can inform visitor management by addressing CES actual use and thereby provide evidence for landscape management and conservation planning and management, including offering a rewarding experience of nature for visitors.

Ecosystem services flow interregionally between sending and receiving regions and their consumption can have impacts on ecosystems in distant regions. Global trade of wild species comprises a multitude of ecosystem services. We identify ecosystem service flows provided by traded species and delineate main sending and receiving regions through species range maps, based on bilateral trade entries in the database of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) from 2014 to 2018. We found that 65% of species represent the service class ‘Science’ (1378 species), 14% ‘Decoration and Pets’ (293), 9% ‘Entertainment’ (188), 4.7% ‘Conservation’ (96), 4.6% ‘Education’ (95) and 2.7% ‘Medicine’ (54). Sending regions are predominantly located in the ‘global South’ and receiving regions in the ‘global North’. Of the traded species 12.3% are threatened and 83.9% may become so without regulation. Of the main sending regions 24.1% are protected. Results show that main sending and main receiving regions differ depending on the ecosystem service. By linking actual trade data from CITES with different types of services, traded service-providing species can be directly assigned to service classes. Through the novel approach of identifying sending regions based on species-specific range maps, the study enables spatial analyses down to a 100x100km scale within countries and regions globally for more targeted conservation actions.

We present a method for automatised detection and analysis of quasi-periodic lineament structures from images at pixel-precision. The method exploits properties of the images' frequency domain found by using the Fourier transform. We developed this method with the goal of detecting lineament structures in an image of the Hathor cliff of comet 67P/Churyumov-Gerasimenko, which are caused by layerings and furrows in the nucleus material. Using our method, we determined the orientation and wavelength-range of these structures. The detected layering edges have similar orientations, spatial separations of 9-20 m, and are ubiquitous throughout the image. We suggest that the layerings are a global feature of the comet nucleus that provide information about formation and evolution of comet 67P. The furrows are non-uniformly distributed throughout the image. Their orientation is broadly parallel to the direction of the local gravity vector at the Hathor cliff, with spacings similar to that of the layering structures. The furrows are interpreted as signatures of local down-slope movement of cliff material. We demonstrate that the developed method is broadly applicable to the detection and analysis of various kinds of quasi-periodic structures like geological layering, folding and faulting, and texture analysis in general. In order to facilitate the application of our method, this paper is accompanied by a demo program written in Matlab.