What next? Rewilding as a radical future for the British countryside

Rewilding is an optimistic environmental agenda to reverse the loss of biodiversity and reconnect society with nature. This chapter explores Britain’s ecological history, back to the Last Interglacial before the arrival of modern humans, when the climate was similar to today, to analyse how conservationists can learn from the past to rewild the ecosystems of the present and prepare for an uncertain future. Because there is no single point in history that should or could be recreated, rewilding focuses on re-establishing naturally dynamic ecological processes that, through an appropriate sequence of species reintroductions, attempts to move the ecosystem towards a more appropriately biodiverse and functional state. A state that is self-sustaining in the present climate, and that projected for the near future. Specifically, this chapter explores a rewilding solution to conservation challenges associated with over-grazing, limited germination niche availability, and river dynamics: the reintroduction of wolves, wild boar, and beaver respectively. This sequence of reintroductions is suggested to be complimentary, each altering ecosystem dynamics to facilitate the return of the next. Evidence indicates wolves will reduce deer abundance and re-distribute browsing intensity promoting tree regeneration, particularly in riparian areas, increasing woodland availability to the more habitat-dependent wild boar and beaver. An important message behind rewilding is that a rich biodiversity with all guilds well represented, including the ones that polarize public opinion, such as large predators, are important components of ecosystem service rich and self-sustaining ecosystems, particularly in core areas

Resource considerate data routing through satellite networks

In many envisaged satellite-based networks, such as constellations or federations, there often exists a desire to reduce data latency, increase delivered data volume, or simply exploit unused resources. A strategy is presented that achieves efficient routing of data, in a store-carry-forward fashion, through satellite networks that exhibit delay- and disruption-tolerant network characteristics. This network-layer protocol, termed Spae, exploits information about the schedule of future contacts between network nodes, because satellite motion is deterministic, along with the capacity of these contacts to route data in such a way as to avoid significant overcommitment of data along a resource limited journey. Results from simulations of a federated satellite system indicate consistent benefit in terms of network performance over other, less-sophisticated, conventional methods, and comparable performance to a packet-optimal, full-knowledge approach

Fast maximum likelihood estimation using continuous-time neural point process models

A recent report estimates that the number of simultaneously recorded neurons is growing exponentially. A commonly employed statistical paradigm using discrete-time point process models of neural activity involves the computation of a maximum-likelihood estimate. The time to computate this estimate, per neuron, is proportional to the number of bins in a finely spaced discretization of time. By using continuous-time models of neural activity and the optimally efficient Gaussian quadrature, memory requirements and computation times are dramatically decreased in the commonly encountered situation where the number of parameters p is much less than the number of time-bins n. In this regime, with q equal to the quadrature order, memory requirements are decreased from O(np) to O(qp), and the number of floating-point operations are decreased from O(np2) to O(qp2). Accuracy of the proposed estimates is assessed based upon physiological consideration, error bounds, and mathematical results describing the relation between numerical integration error and numerical error affecting both parameter estimates and the observed Fisher information. A check is provided which is used to adapt the order of numerical integration. The procedure is verified in simulation and for hippocampal recordings. It is found that in 95 % of hippocampal recordings a q of 60 yields numerical error negligible with respect to parameter estimate standard error. Statistical inference using the proposed methodology is a fast and convenient alternative to statistical inference performed using a discrete-time point process model of neural activity. It enables the employment of the statistical methodology available with discrete-time inference, but is faster, uses less memory, and avoids any error due to discretization.National Science Foundation (U.S.) (NSF grant DMS-1042134

Entorhinal–hippocampal neuronal circuits bridge temporally discontiguous events

The entorhinal cortex (EC)–hippocampal (HPC) network plays an essential role for episodic memory, which preserves spatial and temporal information about the occurrence of past events. Although there has been significant progress toward understanding the neural circuits underlying the spatial dimension of episodic memory, the relevant circuits subserving the temporal dimension are just beginning to be understood. In this review, we examine the evidence concerning the role of the EC in associating events separated by time—or temporal associative learning—with emphasis on the function of persistent activity in the medial entorhinal cortex layer III (MECIII) and their direct inputs into the CA1 region of HPC. We also discuss the unique role of Island cells in the medial entorhinal cortex layer II (MECII), which is a newly discovered direct feedforward inhibitory circuit to CA1. Finally, we relate the function of these entorhinal cortical circuits to recent findings concerning hippocampal time cells, which may collectively activate in sequence to bridge temporal gaps between discontiguous events in an episode.RIKEN Brain Science InstituteHoward Hughes Medical InstituteJPB Foundatio

Evaluation of the Water Footprint of Beef Cattle Production in Nebraska

Data were compiled on feed usage to model the amount of water needed to produce beef in typical Nebraska production systems. Production systems where cows were wintered on corn residue utilized 18% less water than systems utilizing native range as a wintering source, because of water allocations. Therefore, the water footprint (gallons of water required to produce one pound of boneless meat) was decreased by 18%. In addition, increasing the dietary inclusion of distillers grains from 0% to 40% decreased the water footprint in the finishing phase by 29%, again based on water allocation. Utilizing corn residue and distillers grains in Nebraska beef cattle systems decreases the overall water footprint of production. Additionally, the water footprint of the systems analyzed was 80% green water as rain, minimizing the environmental impact of beef production on freshwater use and ecological water balance

Acquisition of “Start” and “Stop” response thresholds in peak-interval timing is differentially sensitive to protein synthesis inhibition in the dorsal and ventral striatum

Time-based decision-making in peak-interval timing procedures involves the setting of response thresholds for the initiation (“Start”) and termination (“Stop”) of a response sequence that is centered on a target duration. Using intracerebral infusions of the protein synthesis inhibitor anisomycin, we report that the acquisition of the “Start” response depends on normal functioning (including protein synthesis) in the dorsal striatum (DS), but not the ventral striatum (VS). Conversely, disruption of the VS, but not the DS, impairs the acquisition of the “Stop” response. We hypothesize that the dorsal and ventral regions of the striatum function as a competitive neural network that encodes the temporal boundaries marking the beginning and end of a timed response sequence

Space mission resilience with inter-satellite networking

Satellites typically operate in isolation from their orbiting counterparts, but communicating only with ground-based infrastructure leaves them susceptible to the consequences of on-board anomalies. Loss of payload, communication system, or other sub-system function could render the entire satellite inoperable. This susceptibility can be partially mitigated through the addition of an inter-satellite networking capability, which offers value in terms of increased general performance and an increased resilience to on-board anomalies. While a typical platform can be modelled to exhibit only two fundamental states: operational and failed, a networking-capable platform (specifically one with an inter-satellite communication capability) exhibits six states, each reached through a unique combination of sub-system malfunctions. The result of this added resilience is a reduction in the likelihood of the satellite reaching a fully-failed state. Simulations for independent and networking-capable systems are presented that illustrate the benefits and limitations of inter-satellite networking in terms of failure resilience. It is shown that whilst a networked system can be expected to reach greater levels of performance utility, sub-system anomalies are found to result in greater percentage levels of performance degradation compared to a non-networking-capable system with similar characteristics

Validation of the self-completed Cambridge-Hopkins questionnaire (CH-RLSq) for ascertainment of restless legs syndrome (RLS) in a population survey.

BACKGROUND AND PURPOSE: Epidemiological studies of restless legs syndrome (RLS) have been limited by lack of a well validated patient-completed diagnostic questionnaire that has a high enough specificity to provide a reasonable positive predictive value. Most of the currently used patient completed diagnostic questionnaires have neither been validated nor included items facilitating the differential diagnosis of RLS from conditions producing similar symptoms. The Cambridge-Hopkins diagnostic questionnaire for RLS (CH-RLSq) was developed with several iterations to include items covering the basic diagnostic features of RLS and to provide some basic differential diagnosis. This validation study sought to determine the sensitivity and specificity of the RLS diagnosis based on this questionnaire. PATIENTS AND METHODS: The CH-RLSq was completed by 2005 blood donors who were asked to consent to being contacted for a telephone diagnostic interview. A scoring criterion was established for ascertainment of RLS based on the clinical definition of the disorder and the exclusion of "mimic" conditions. A weighted sample (N=185) of all completed questionnaires was selected for expert clinical diagnosis of RLS using the validated Hopkins Telephone Diagnostic Interview (HDTI). The telephone interviewers were blinded to all questionnaire responses. RESULTS: A telephone diagnosis was obtained on 183 of the sample's 185 questionnaires. The questionnaire's normalized sensitivity and specificity were 87.2% and 94.4%, respectively, for RLS compared to not RLS. The positive predictive values in this sample were 85.5%. CONCLUSIONS: The Cambridge-Hopkins RLS questionnaire provides a reasonable level of sensitivity and specificity for ascertainment of RLS in population-based studies