A striking neurochemical form of compartmentalization has been found in the striatum of humans and other species, dividing it into striosomes and matrix. The function of this organization has been ...unclear, but the anatomical connections of striosomes indicate their relation to emotion-related brain regions, including the medial prefrontal cortex. We capitalized on this fact by combining pathway-specific optogenetics and electrophysiology in behaving rats to search for selective functions of striosomes. We demonstrate that a medial prefronto-striosomal circuit is selectively active in and causally necessary for cost-benefit decision-making under approach-avoidance conflict conditions known to evoke anxiety in humans. We show that this circuit has unique dynamic properties likely reflecting striatal interneuron function. These findings demonstrate that cognitive and emotion-related functions are, like sensory-motor processing, subject to encoding within compartmentally organized representations in the forebrain and suggest that striosome-targeting corticostriatal circuits can underlie neural processing of decisions fundamental for survival.
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•A specific fronto-striatal decision circuit is activated by cost-benefit conflict•It primarily targets striatal striosomes, linked to limbic functions of striatum•Its optogenetic control selectively alters decisions under cost-benefit conflict•Its corticostriatal control is exerted through a striatal inhibitory microcircuit
Optogenetic manipulation and electrophysiology of a circuit connecting the prefrontal cortex to striosomes—compartmentalized structures of the striatum—reveals that it has a selective role in influencing decision-making for choices with cost-benefit tradeoffs.
Objective
This essay aims to explain the impasse in debates concerning Confederate monuments in public spaces by noting a difference in unstated philosophical assumptions.
Method
I examine two ...positions in this debate, offering an explanation for the inability for opposing sides to engage. The analytical framework has its basis in philosophical debates regarding objectivity in scientific theory selection.
Results
Arguably, the impasse in this debate concerns underlying ethical principles: one that assesses morality based on intentions that motivate actions (namely, the motivation for erecting a monument) and one that assesses morality based on consequences of actions (namely, the consequences of removing monuments).
Conclusions
The locus of discussion can shift to these philosophical principles, offering a novel avenue for discussion and, hence, reconciliation. I suggest a fate for Confederate monuments that is responsive to both sides’ concerns and is informed by another country's attempt to reconcile with its troubled past.
The oxygenation of Earth’s surface environment dramatically altered key biological and geochemical cycles and ultimately ushered in the rise of an ecologically diverse biosphere. However, atmospheric ...oxygen partial pressures (pO₂) estimates for large swaths of the Precambrian remain intensely debated. Here we evaluate and explore the use of carbonate cerium(Ce) anomalies (Ce/Ce*) as a quantitative atmospheric pO₂ proxy and provide estimates of Proterozoic pO₂ using marine carbonates from a unique Precambrian carbonate succession—the Paleoproterozoic Pethei Group. In contrast to most previous work, wemeasure Ce/Ce* on marine carbonate precipitates that formed in situ across a depth gradient, building on previous detailed sedimentology and stratigraphy to constrain the paleo-depth of each sample. Measuring Ce/Ce* across a full platform to basin depth gradient, we found only minor depleted Ce anomalies restricted to the platform and upper slope facies. We combine these results with a Ce oxidation model to provide a quantitative constraint on atmospheric pO₂ 1.87 billion years ago (Ga). Our results suggest Paleoproterozoic atmospheric oxygen concentrations were low, near 0.1% of the present atmospheric level. This work provides another crucial line of empirical evidence that atmospheric oxygen levels returned to low concentrations following the Lomagundi Event, and remained low enough for large portions of the Proterozoic to have impacted the ecology of the earliest complex organisms.
Effective evaluation of costs and benefits is a core survival capacity that in humans is considered as optimal, “rational” decision-making. This capacity is vulnerable in neuropsychiatric disorders ...and in the aftermath of chronic stress, in which aberrant choices and high-risk behaviors occur. We report that chronic stress exposure in rodents produces abnormal evaluation of costs and benefits resembling non-optimal decision-making in which choices of high-cost/high-reward options are sharply increased. Concomitantly, alterations in the task-related spike activity of medial prefrontal neurons correspond with increased activity of their striosome-predominant striatal projection neuron targets and with decreased and delayed striatal fast-firing interneuron activity. These effects of chronic stress on prefronto-striatal circuit dynamics could be blocked or be mimicked by selective optogenetic manipulation of these circuits. We suggest that altered excitation-inhibition dynamics of striosome-based circuit function could be an underlying mechanism by which chronic stress contributes to disorders characterized by aberrant decision-making under conflict.
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•Chronic stress produces abnormal cost-benefit integration in decision-making•This reflects abnormal in-task firing dynamics of prefrontal and striatal cells•This circuit disorder leads to highly elevated firing of striosomal output neurons•Optogenetic manipulations can mimic or reverse these behavioral effects of stress
A brain circuit that connects the prefrontal cortex with striosomes in the striatum is activated in cost-benefit decision-making and becomes severely impaired after chronic stress, producing abnormal weighing of cost and benefit.
Both the abiotic environment and the composition of animal and plant communities change with elevation. For mutualistic species, these changes are expected to result in altered partner availability, ...and shifts in context-dependent benefits for partners. To test these predictions, we assessed the network structure of terrestrial ant-plant mutualists and how the benefits to plants of ant inhabitation changed with elevation in tropical forest in Papua New Guinea. At higher elevations, ant-plants were rarer, species richness of both ants and plants decreased, and the average ant or plant species interacted with fewer partners. However, networks became increasingly connected and less specialized, more than could be accounted for by reductions in ant-plant abundance. On the most common ant-plant, ants recruited less and spent less time attacking a surrogate herbivore at higher elevations, and herbivory damage increased. These changes were driven by turnover of ant species rather than by within-species shifts in protective behaviour. We speculate that reduced partner availability at higher elevations results in less specialized networks, while lower temperatures mean that even for ant-inhabited plants, benefits are reduced. Under increased abiotic stress, mutualistic networks can break down, owing to a combination of lower population sizes, and a reduction in context-dependent mutualistic benefits.
Acute kidney injury (AKI) is a common complication following cardiac surgery performed on cardiopulmonary bypass (CPB) and has important implications for prognosis. The aetiology of cardiac ...surgery‐associated AKI is complex, but renal hypoxia, particularly in the medulla, is thought to play at least some role. There is strong evidence from studies in experimental animals, clinical observations and computational models that medullary ischaemia and hypoxia occur during CPB. There are no validated methods to monitor or improve renal oxygenation during CPB, and thus possibly decrease the risk of AKI. Attempts to reduce the incidence of AKI by early transfusion to ameliorate intra‐operative anaemia, refinement of protocols for cooling and rewarming on bypass, optimization of pump flow and arterial pressure, or the use of pulsatile flow, have not been successful to date. This may in part reflect the complexity of renal oxygenation, which may limit the effectiveness of individual interventions. We propose a multi‐disciplinary pathway for translation comprising three components. Firstly, large‐animal models of CPB to continuously monitor both whole kidney and regional kidney perfusion and oxygenation. Secondly, computational models to obtain information that can be used to interpret the data and develop rational interventions. Thirdly, clinically feasible non‐invasive methods to continuously monitor renal oxygenation in the operating theatre and to identify patients at risk of AKI. In this review, we outline the recent progress on each of these fronts.
Many publications lack sufficient background information (e.g. location) to be interpreted, replicated, or reused for synthesis. This impedes scientific progress and the application of science to ...practice. Reporting guidelines (e.g. checklists) improve reporting standards. They have been widely taken up in the medical sciences, but not in ecological and agricultural research. Here, we use a community-centred approach to develop a reporting checklist (AgroEcoList 1.0) through surveys and workshops with 23 experts and the wider agroecological community. To put AgroEcoList in context, we also assessed the agroecological community's perception of reporting standards in agroecology. A total of 345 researchers, reviewers, and editors, responded to our survey. Although only 32% of respondents had prior knowledge of reporting guidelines, 76% of those that had said guidelines improved reporting standards. Overall, respondents agreed on the need of AgroEcolist 1.0; only 24% of respondents had used reporting guidelines before, but 78% indicated they would use AgroEcoList 1.0. We updated AgroecoList 1.0 based on respondents' feedback and user-testing. AgroecoList 1.0 consists of 42 variables in seven groups: experimental/sampling set-up, study site, soil, livestock management, crop and grassland management, outputs, and finances. It is presented here, and is also available on github (https://github.com/AgroecoList/Agroecolist). AgroEcoList 1.0 can serve as a guide for authors, reviewers, and editors to improve reporting standards in agricultural ecology. Our community-centred approach is a replicable method that could be adapted to develop reporting checklists in other fields. Reporting guidelines such as AgroEcoList can improve reporting standards and therefore the application of research to practice, and we recommend that they are adopted more widely in agriculture and ecology.
Author‐level metrics are a widely used measure of scientific success. The h‐index and its variants measure publication output (number of publications) and research impact (number of citations). They ...are often used to influence decisions, such as allocating funding or jobs. Here, we argue that the emphasis on publication output and impact hinders scientific progress in the fields of ecology and evolution because it disincentivizes two fundamental practices: generating impactful (and therefore often long‐term) datasets and sharing data. We describe a new author‐level metric, the data‐index, which values both dataset output (number of datasets) and impact (number of data‐index citations), so promotes generating and sharing data as a result. We discuss how it could be implemented and provide user guidelines. The data‐index is designed to complement other metrics of scientific success, as scientific contributions are diverse and our value system should reflect that both for the benefit of scientific progress and to create a value system that is more equitable, diverse, and inclusive. Future work should focus on promoting other scientific contributions, such as communicating science, informing policy, mentoring other scientists, and providing open‐access code and tools.
Our current value system in academia centers around publications. This hinders scientific progress as it disincentivizes fundamental practices, such as generating and sharing data. Here, we describe a new author‐level metric (the data‐index) which values these practices and promotes them as a result. The data‐index is designed to complement other indices of scientific success, and create a broader perspective of scientific impact.
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