Recent studies have shown that hippocampal “time cells” code for sequential moments in temporally organized experiences. However, it is currently unknown whether these temporal firing patterns ...critically rely on upstream cortical input. Here we employ an optogenetic approach to explore the effect of large-scale inactivation of the medial entorhinal cortex on temporal, as well as spatial and object, coding by hippocampal CA1 neurons. Medial entorhinal inactivation produced a specific deficit in temporal coding in CA1 and resulted in significant impairment in memory across a temporal delay. In striking contrast, spatial and object coding remained intact. Further, we extended the scope of hippocampal phase precession to include object information relevant to memory and behavior. Overall, our work demonstrates that medial entorhinal activity plays an especially important role for CA1 in temporal coding and memory across time.
•MEC was inactivated during temporal, spatial, and object processing in a memory task•CA1 time cells and memory performance were impaired during MEC inactivation•Spatial and object-selective coding remained stable during MEC inactivation•Highly object-selective spiking exhibited theta phase precession
Robinson and Priestley et al. combine single-unit recording with large-scale optogenetic inactivation in animals performing a temporal association memory task to assess the role of MEC in the generation of hippocampal temporal, spatial, and object-selective firing fields.
The Foreign Agents Registration Act ("FARA") is a sweeping and generally underenforced public-disclosure statute. Enacted in 1938, FARA was used during World War II to target fascist propaganda, but ...by the 1960s its enforcement had shifted to lobbyists and public-relations firms for foreign governments. After the 2016 presidential election, FARA has gained favor among policymakers and prosecutors as a central tool to respond to a range of foreign influence in U.S. politics, including foreign lobbying, electioneering, and disinformation.
This Article argues that FARA's breadth creates substantial risk that it will be used in a politicized manner. In the past decade, analogous transparency laws in other countries-often justified by reference to FARA-have been weaponized to target dissenting voices with the stigma and burden of registering as a "foreign agent." This Article undertakes an analysis of FARA to show how its broad and unclear provisions make FARA susceptible to being similarly used in the United States, especially against nonprofits, the media, and public officials. It examines three cases in which FARA was arguably enforced in a politicized manner, explains why strengthening the Act's enforcement would likely exacerbate this problem, and discusses the Act's potential constitutional deficiencies under the Supreme Court's recent First Amendment jurisprudence.
The Article ends by weighing the merits of using FARA to address different types of foreign influence. It posits that transparency provisions like those in FARA are most appropriate, and on strongest ground, when applied to (1) those who clearly are acting at the direction or control of a foreign government or political party; and (2) when the covered activity involves core democratic processes, such as lobbying or electioneering. It warns that using FARA to target disinformation is unlikely to be effective and presents a high risk of politicized abuse. Based on these insights, it suggests three potential strategies for FARA reform.
Aquaculture is the fastest growing food production industry, and the vast majority of aquaculture products are derived from Asia. The quantity of aquaculture products directly consumed is now greater ...than that resulting from conventional fisheries. The nutritional value of aquatic products compares favourably with meat from farm animals because they are rich in micronutrients and contain high levels of healthy omega-3 fatty acids. Compared with farm animals, fish are more efficient converters of energy and protein. If the aquaculture sector continues to expand at its current rate, production will reach 132million tonnes of fish and shellfish and 43million tonnes of seaweed in 2020. Future potential for marine aquaculture production can be estimated based on the length of coastline, and for freshwater aquaculture from available land area in different countries. The average marine production in 2005 was 103tonnes per km coastline, varying from 0 to 1721 (China). Freshwater aquaculture production in 2005 averaged 0.17tonnes/ha, varying from 0 to close to 6tonnes per ha (Bangladesh), also indicating potential to dramatically increase freshwater aquaculture output. Simple estimations indicate potential for a 20-fold increase in world aquaculture production. Limits imposed by the availability of feed resources would be lessened by growing more herbivorous species and by using more of genetically improved stocks.
Aquaculture generally trails far behind plant and farm animal industries in utilizing selective breeding as a tool to improve the biological efficiency of production. It is estimated that at present less than 10% of aquaculture production is based on genetically improved stocks, despite the fact that annual genetic gains reported for aquatic species are substantially higher than that of farm animals. With an average genetic gain in growth rate of 12.5% per generation, production may be dramatically increased if genetically improved animals are used. Importantly, animals selected for faster growth have also been shown to have improved feed conversion and higher survival, implying that increased use of selectively bred stocks leads to better utilization of limited resources such as feed, labour, water, and available land and sea areas.
► We demonstrate existence of vast potential for increased aquaculture production. ► The largest potential for aquaculture lies in the marine environment. ► Selection responses in aquaculture species are higher than for conventional livestock. ► More use of genetically improved stocks may dramatically increase aquaculture output. ► Genetically improved stocks are critical for better utilization of limited resources.
The hippocampus is crucial for spatial navigation and episodic memory formation. Hippocampal place cells exhibit spatially selective activity within an environment and have been proposed to form the ...neural basis of a cognitive map of space that supports these mnemonic functions. However, the direct influence of place cell activity on spatial navigation behavior has not yet been demonstrated. Using an ‘all-optical’ combination of simultaneous two-photon calcium imaging and two-photon optogenetics, we identified and selectively activated place cells that encoded behaviorally relevant locations in a virtual reality environment. Targeted stimulation of a small number of place cells was sufficient to bias the behavior of animals during a spatial memory task, providing causal evidence that hippocampal place cells actively support spatial navigation and memory.
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•Two-photon optogenetics in VR enables targeted manipulation of place cell ensembles•Activating specific place cell ensembles drives their spatially associated behavior•Place cell stimulation inhibits endogenous place code expression and triggers remapping•Direct evidence for a causal role of place cells in spatial navigation
Selective stimulation of a small number of hippocampal place cells in mice provides causal evidence that hippocampal place cells actively support spatial navigation and memory.
According to schema theory as proposed by Piaget and Bartlett, learning involves the assimilation of new memories into networks of preexisting knowledge, as well as alteration of the original ...networks to accommodate the new information. Recent evidence has shown that rats form a schema of goal locations and that the hippocampus plays an essential role in adding new memories to the spatial schema. Here we examined the nature of hippocampal contributions to schema updating by monitoring firing patterns of multiple CA1 neurons as rats learned new goal locations in an environment in which there already were multiple goals. Before new learning, many neurons that fired on arrival at one goal location also fired at other goals, whereas ensemble activity patterns also distinguished different goal events, thus constituting a neural representation that linked distinct goals within a spatial schema. During new learning, some neurons began to fire as animals approached the new goals. These were primarily the same neurons that fired at original goals, the activity patterns at new goals were similar to those associated with the original goals, and new learning also produced changes in the preexisting goal-related firing patterns. After learning, activity patterns associated with the new and original goals gradually diverged, such that initial generalization was followed by a prolonged period in which new memories became distinguished within the ensemble representation. These findings support the view that consolidation involves assimilation of new memories into preexisting neural networks that accommodate relationships among new and existing memories.
Populations of broadcast spawning marine organisms often have large sizes and are exposed to reduced genetic drift. Under such scenarios, strong selection associated with spatial environmental ...heterogeneity is expected to drive localized adaptive divergence, even in the face of connectivity. We tested this hypothesis using a seascape genomics approach in the commercially important greenlip abalone (Haliotis laevigata). We assessed how its population structure has been influenced by environmental heterogeneity along a zonal coastal boundary in southern Australia linked by strong oceanographic connectivity. Our data sets include 9,109 filtered SNPs for 371 abalones from 13 localities and environmental mapping across ~800 km. Genotype–environment association analyses and outlier tests defined 8,786 putatively neutral and 323 candidate adaptive loci. From a neutral perspective, the species is better represented by a metapopulation with very low differentiation (global FST = 0.0081) and weak isolation by distance following a stepping‐stone model. For the candidate adaptive loci, however, model‐based and model‐free approaches indicated five divergent population clusters. After controlling for spatial distance, the distribution of putatively adaptive variation was strongly correlated to selection linked to minimum sea surface temperature and oxygen concentration. Around 80 candidates were annotated to genes with functions related to high temperature and/or low oxygen tolerance, including genes that influence the resilience of abalone species found in other biogeographic regions. Our study includes a documented example about the uptake of genomic information in fisheries management and supports the hypothesis of adaptive divergence due to coastal environmental heterogeneity in a connected metapopulation of a broadcast spawner.
see also the Perspective by Lampert
By taking into account the turbine type, terrain, wind climate and layout, the effects of wind turbine wakes and other losses, engineering models enable the rapid estimation of energy yields for ...prospective and existing wind farms. We extend the capability of engineering models, such as the existing deep-array wake model, to account for additional losses that may arise due to the presence of clusters of wind farms, such as the global blockage effect and large-scale wake effects, which become more significant with increasing thermal stratification. The extended strategies include an enhanced wind-farm-roughness approach which assumes an infinite wind farm, and recent developments account for the upstream flow blockage. To test the plausibility of such models in capturing the additional blockage and wake losses in real wind farm clusters, the extended strategies are compared with large-eddy simulations of the flow through a cluster of three wind farms located in the German sector of the North Sea, as well as real measurements of wind power within these wind farms. Large-eddy simulations and wind farm measurements together suggest that the extensions of the Openwind model help capture the different flow features arising from flow blockage and cluster effects, but further model refinement is needed to account for higher-order effects, such as the effect of the boundary-layer height, which is not currently included in standard engineering models.
The debates on regionalism have been polarized between European Union (EU) scholars and non-EU scholars, with the assumption being that regionalism within the EU and other regions of the world are ...quite distinct, with little to be learnt from dialogue with each other. This book challenges such assumptions and calls for a genuine debate between scholars of regionalism.
This book demonstrates that more can and needs to be learned about regional integration all over the world through comparison and reflection on specific regional trends. Beginning with a theoretically driven introduction, leading experts in the field are brought together to offer a series of case studies on regional integration within Latin America, Africa, Asia, North America and Europe. In Part III the authors investigate the links between the EU and selected other regional organisations and processes, exploring the dynamics through which these interregional relations are developing and the implications they have for the study of contemporary regionalism/regionalisation both inside and beyond the continent of Europe. The conclusions set out a challenging research agenda for comparative studies in the field.
Addressing one of the under-explored aspects of EU studies, the EU's coexistence with other pan-continental/regional organisations in the European continent, this book will be of interest to students and scholars of regionalism, IPE, European Studies and international politics.
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