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Agricultural landscapes impede woodland ground-dwelling beetle colonisation and establishment in planted woodlands
Get PDFGlobal insect declines have been partly attributed to habitat loss and agricultural intensification. Large-scale habitat restoration is crucial to address this biodiversity crisis, with woodlands representing a key habitat that supports diverse insect communities, particularly beetle assemblages. However, little is known about beetle colonisation and establishment processes as woodland is created. Using data from a long-term natural experiment (the WrEN project), we investigate the relative importance of local and landscape characteristics on ground-dwelling beetle colonisation and establishment across 60 UK secondary broadleaved woodlands. Our sites, planted 12 β 160 years ago, range in size between 0.5 β 32 ha and are embedded in landscapes ranging from 20 β 90 % agriculture. Using structural equation models, we show that woodland generalist and specialist beetles were more abundant in larger woodlands and more species-rich in woodlands with a lower proportion of surrounding agriculture. Woodland specialists were more abundant in woodlands with lower tree densities, a positive indirect effect of woodland age. Beetle community composition varied according to woodland age and
structure, with younger and more homogenous woodlands having more non-woodland species. These findings suggest that the agricultural matrix may hinder woodland beetle colonisation into newly established woodlands in farmed landscapes. To enhance beetle biodiversity, woodland restoration initiatives should prioritise planting larger sites, and active management such as selective thinning that reduces tree density and increases structural heterogeneity. We highlight a potential paradox between the benefits of restoration that avoids landscapes with high agriculture to promote beetle colonisation vs. targeting these landscapes in efforts to enhance biodiversity
Between collective self-reliance and cooperation: Yugoslavia and the developing countries in the non-alignment space
No full textYugoslavia played a key role in the history of the Non-Aligned Movement, as a founding member and key actor in shaping its approach to economic development. Inspired by a strong socialist and developmental ideology, Yugoslaviaβs active presence in non-aligned international cooperation was marked by its entanglement with the developing world. Rebalancing the global terms of trade and guaranteeing a more equal economic development based on interdependence between developing countries was a key priority for the non-aligned movement. As this article shows, collective self-reliance was a flagship policy of non-aligned economic development, one dedicated to maintaining distinctive and sovereign paths to economic growth for member countries. This approach was crucial in building relations between Yugoslavia and its partners in the developing world. The rather malleable and fuzzy nature of self-reliance cast a sufficiently wide net over relations of economic cooperation, one that allowed Yugoslav companies to position themselves as key actors in these exchanges. At the same time, as the article illustrates, the non-aligned movement was confronted by challenges that partly undermined its founding principles, especially in relation to its stated aim of rebalancing north-south power dynamics in trade and debt politics. Through a focus on Yugoslaviaβs relations with Panama and Zambia, this article excavates what was happening behind the grand gestures of international solidarity and it provides a diagnosis of the movementβs shortcomings in its approach to self-reliance
Effect of drought on wildlife activity at artificial waterholes
Get PDFAcross southern Africa artificial waterholes have been introduced into many national parks to reduce the pressure of water scarcity on animals during drought. However, their introduction can shift ecological dynamics,
and many artificial waterholes are now being removed. As global temperatures rise, droughts are predicted to become more frequent and more severe. Whether to retain or remove artificial waterholes thus presents a management dilemma. Here, we examine the effect of an extreme drought on artificial waterhole use in the Kruger National Park, South Africa. Comparing camera trap data collected during a one-in-twenty year drought with observation from a non-drought year, we quantify shifts in waterhole visitation patterns between years. The
majority of the species show differences in waterhole use between drought and non-drought years. Species showing the largest temporal shifts include kudu and white rhinoceros, whereas elephants and warthogs show little change between years. Temporal overlaps between species pairs were also highly shifted, with the majority of species overlapping more in drought years, although some (e.g. buffalo and impala) show the opposite trend. Asynchronous shifts in species daily activity cycle may have cascading impacts on interspecific competition,
predator-prey interactions, and multi-host disease dynamics. Our study illustrates how the interaction between drought and management choices to mitigate impacts of climate change may have complex and unforeseen ecological consequences. We show that, during drought, artificial waterholes are visited more frequently, likely increasing the frequency of interspecific interactions, including between ungulate herbivores and their predators, and elevating risk of disease spillover
First differential measurement of the single Ο+ production cross section in neutrino neutral-current scattering
Get PDFSince its first observation in the 1970s, neutrino-induced neutral-current single positive pion production (NC1Ο +) has remained an elusive and poorly understood interaction channel. This process is a significant background in neutrino oscillation experiments and studying it further is critical for the physics program of next-generation accelerator-based neutrino oscillation experiments. In this Letter we present the first double-differential cross-section measurement of NC1Ο + interactions using data from the ND280 detector of the T2K experiment collected in Ξ½-beam mode. The measured flux-averaged integrated cross-section is Ο = (6.07Β±1.22)Γ10β41 cm2 /nucleon. We compare the results on a hydrocarbon target to the predictions of several neutrino interaction generators and final-state interaction models. While model predictions agree with the differential results, the data shows a weak preference for a cross-section normalization approximately 30% higher than predicted by most models studied in this Letter
Inclusive electron scattering in the resonance region off a hydrogen target with CLAS12
Get PDFInclusive electron scattering cross sections off a hydrogen target at a beam energy of 10.6 GeV have been measured with data collected from the CLAS12 spectrometer at Jefferson Laboratory. These first absolute cross sections from CLAS12 cover a wide kinematic area in invariant mass W of the final state hadrons from the pion threshold up to 2.5 GeV for each bin in virtual photon four-momentum transfer squared Q2 from 2.55 to 10.4 GeV2 owing to the large scattering angle acceptance of the CLAS12 detector. Comparison of the cross sections with the resonant contributions computed from the CLAS results on the nucleon resonance electroexcitation amplitudes has demonstrated a promising opportunity to extend the information on their Q2 evolution up to 10 GeV2 . Together these results from CLAS and CLAS12 offer good prospects for probing the nucleon parton distributions at large fractional parton momenta x for W < 2.5 GeV, while covering the range of distances where the transition from the strongly coupled to the perturbative regimes is expected
First observation of the Ξ0 b β Ξ+ c Dβ s K+Kβ decay and search for pentaquarks in the Ξ+ c Dβ s system
Get PDFMaking cow-free caseins and casein micelles
No full textA key step in the precision fermentation of casein proteins is correct
phosphorylation to generate one or more short linear sequence motifs
(SLiMs) containing three or more phosphorylated seryl residues. The
work of Balasubramanian et al. takes us a step closer to that goal
by showing that two bacterial phosphokinases are promising alternatives to the mammalian Golgi phosphokinases and casein kinase-II
Interdisciplinary Learning: Addressing the Implementation Gap [Keynote presentation]
Get PDFNo abstract available
Characterizing neuronal and population responses to electrical stimulation in the human hippocampo-cortical network
Get PDFBackground:
The hippocampus is a common target for direct electrical stimulation (DES). While considerable research has focused on clinical outcomes of various stimulation protocols, the precise neural dynamics of DES in the human hippocampus remain poorly understood, limiting our ability to model and predict hippocampal neural activity. Conventional stereotactic electrodes provide limited insight as the recorded signal becomes saturated during DES, allowing to only record LFP activity from stimulation in sufficiently distant areas. Behnke-Fried electrodes circumvent this limitation, enabling simultaneous recording of local hippocampal single-unit and LFP activity during stimulation.
Objective:
We aimed to characterize the neural responses to single pulse DES in the hippocampus and surrounding cortical areas at both single-neuron and population levels.
Methods:
We collected data from 34 hippocampally implanted Behnke-Fried electrodes across seven epilepsy patients. This unique approach allowed us to monitor both local field potentials and single neuron activity (N = 136) in response to 1 ms bipolar single pulse DES in the hippocampus and surrounding neocortex. Single pulses were administered systematically across electrode leads terminating in the neocortex, allowing us to assess both local responses and network propagation effects.
Results:
Despite high stimulation intensity, only 29 % of single units exhibited measurable responses to hippocampal stimulation. Responsive neurons displayed a stereotypical pattern: an initial excitatory response (cluster size: 110 ms, p = 0.0017) followed by an inhibitory 'silent period' of reduced firing (cluster size: 141 ms, p < 0.0005). Both the intensity of the initial excitation and the duration of the silent period were inversely correlated with distance from the stimulation site (peak height: r = β0.94, p < 0.0001; silent duration: r = β0.93, p < 0.0001). LFP responses corroborated these findings in both time and frequency domains. Notably, hippocampal responses to neocortical stimulation revealed a consistent lag of approximately 100 ms. Finally, we found evidence that cortical responses to hippocampal stimulation were modulated by hippocampal theta phase at the time of stimulation.
Conclusions:
We provide the first comprehensive characterization of hippocampal responses to DES at both neuronal and population levels in the human hippocampo-cortical network. Our findings of stereotypical response patterns and quantifiable phase-dependent network effects provide crucial parameters to inform future stimulation paradigms targeting the human memory system
Inverting Laguerre tessellations: recovering tessellations from the volumes and centroids of their cells using optimal transport
Get PDFIn this paper we study an inverse problem in convex geometry, inspired by a problem in materials science. Firstly, we consider the question of whether a Laguerre tessellation (a partition by convex polytopes) can be recovered from only the volumes and centroids of its cells. We show that this problem has a unique solution and give a constructive way of computing it using optimal transport theory and convex optimisation. Secondly, we consider the problem of fitting a Laguerre tessellation to synthetic volume and centroid data. Given some target volumes and centroids, we seek a Laguerre tessellation such that the difference between the volumes and centroids of its cells and the target volumes and centroids is minimised. For an appropriate objective function and suitable data, we prove that local minimisers of this problem can be constructed using convex optimisation. We also illustrate our results numerically. There is great interest in the computational materials science community in fitting Laguerre tessellations to electron backscatter diffraction (EBSD) and x-ray diffraction images of polycrystalline materials. As an application of our results we fit a 2D Laguerre tessellation to an EBSD image of steel
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