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Orbital Frontal Cortex Projections to Secondary Motor Cortex Mediate Exploitation of Learned Rules.
Animals face the dilemma between exploiting known opportunities and exploring new ones, a decision-making process supported by cortical circuits. While different types of learning may bias exploration, the circumstances and the degree to which bias occurs is unclear. We used an instrumental lever press task in mice to examine whether learned rules generalize to exploratory situations and the cortical circuits involved. We first trained mice to press one lever for food and subsequently assessed how that learning influenced pressing of a second novel lever. Using outcome devaluation procedures we found that novel lever exploration was not dependent on the food value associated with the trained lever. Further, changes in the temporal uncertainty of when a lever press would produce food did not affect exploration. Instead, accrued experience with the instrumental contingency was strongly predictive of test lever pressing with a positive correlation between experience and trained lever exploitation, but not novel lever exploration. Chemogenetic attenuation of orbital frontal cortex (OFC) projection into secondary motor cortex (M2) biased novel lever exploration, suggesting that experience increases OFC-M2 dependent exploitation of learned associations but leaves exploration constant. Our data suggests exploitation and exploration are parallel decision-making systems that do not necessarily compete
Estimating Consumption- Based Poverty in the Ethiopia Demographic and Health Survey
Inequalities in health are linked with poverty, but quantifying the health/poverty nexusis hampered by data constraints. In particular, the most common measure of poverty compares consumption with poverty lines, but consumption surveys often do not collect detailed health data. Conversely, the large repository of internationallycomparable Demographic and Health Surveys has detailed health data but no consumption data. This has led DHS researchers who want to control for socioeconomic status use an asset index defined in terms of housing characteristics and the ownership of durable goods. While this is a valid conception of poverty, it is difficult to compare it with the more-common consumption-based measure. This paper presents a simple poverty scorecard for Ethiopia based on the poverty-mapping approach of Elbers et al. (2003). It allows researchers to estimate the likelihood that consumption is below a given poverty line using nine verifiable, inexpensive-to-collect indicators found in both Ethiopiaâs 2005 DHS and in the 2004/5 Household Income, Consumption, and Expenditure Survey. It turns out that the poverty scorecard and the DHS asset index do not generally rank people the same, so estimates of consumptionbased poverty in the DHS should use the poverty scorecard, not the DHS asset index. The bias and precision of scorecard estimates compare well with that of other tools, suggesting that government could use it to track poverty in years between national household expenditure surveys.Keywords: Poverty measurement, asset index, poverty mapping, Africa, Ethiopia, health equit
Characterization of the ZFX family of transcription factors that bind downstream of the start site of CpG island promoters
Our study focuses on a family of ubiquitously expressed human CâHâ zinc finger proteins comprised of ZFX, ZFY and ZNF711. Although their protein structure suggests that ZFX, ZFY and ZNF711 are transcriptional regulators, the mechanisms by which they influence transcription have not yet been elucidated. We used CRISPR-mediated deletion to create bi-allelic knockouts of ZFX and/or ZNF711 in female HEK293T cells (which naturally lack ZFY). We found that loss of either ZFX or ZNF711 reduced cell growth and that the double knockout cells have major defects in proliferation. RNA-seq analysis revealed that thousands of genes showed altered expression in the double knockout clones, suggesting that these TFs are critical regulators of the transcriptome. To gain insight into how these TFs regulate transcription, we created mutant ZFX proteins and analyzed them for DNA binding and transactivation capability. We found that zinc fingers 11â13 are necessary and sufficient for DNA binding and, in combination with the N terminal region, constitute a functional transactivator. Our functional analyses of the ZFX family provides important new insights into transcriptional regulation in human cells by members of the large, but under-studied family of CâHâ zinc finger proteins
Negative Ion Drift and Diffusion in a TPC near 1 Bar
Drift velocity and longitudinal diffusion measurements are reported for a
Negative Ion TPC (NITPC) operating with Helium + carbon disulfide gas mixtures
at total pressures from 160 to 700 torr. Longitudinal diffusion at the
thermal-limit was observed for drift fields up to at least 700 V/cm in all gas
mixtures tested. The results are of particular interest in connection with
mechanical simplification of Dark Matter searches such as DRIFT, and for high
energy physics experiments in which a low-Z, low density, gaseous tracking
detector with no appreciable Lorentz drift is needed for operation in very high
magnetic fields.Comment: 7 pages, 3 figure
Effects of saline irrigation on growth, physiology and quality of Mesembryanthemum crystallinum L., a rare vegetable crop.
World wide increased desertification due to recent global changes enhances the need of irrigation, which, in turn, provokes the risk of soil salinization. Furthermore, limited fresh water resources may increasingly constrain the use of low quality irrigation water. Hence, intensified use of halotolerant crop plants will be necessary, even in Europe.Commercial use of halophytes as fresh food is limited. Several facultative halophytic members of Aizoaceae are nowadays used as special crop plants. A rare leafy vegetable species is the common ice plant Mesembryanthemum crystallinum, a Crassulacean acid metabolism (CAM) species, which is mostly cultivated in India, California, Australia, and New Zealand. It is also known in Europe as a quickly cooked tender vegetable. With their succulent, mellow, slightly salty tasting leaves and young shoots, M. crystallinum is getting interesting as delicious cool flavored salad greens during recent years. However, it is a perishable product and thus, shelf live is short. On the other hand, CAM capacity of M. crystallinum can be largely enhanced by saline irrigation. Increased CAM potentially reduces water and carbon losses.In this project we studied whether moderate salt treatment affects physiology, growth and yield of this rare crop plant. Furthermore, we investigated whether such treatment that enhances the irreversible C3 to CAM shift in young leaves of this CAM species, potentially prolongs shelf live. Results showed that moderate salt treatment did not negatively influence growth, yield and sensory quality. When in CAM, leaves showed reduced transpiration water losses and CAM also reduced carbon losses during storage
Maternal input and infantsâ response to infantâdirected speech
Caregivers typically use an exaggerated speech register known as infantâdirected speech (IDS) in communication with infants. Infants prefer IDS over adultâdirected speech (ADS) and IDS is functionally relevant in infantâdirected communication. We examined interactions among maternal IDS quality, infantsâ preference for IDS over ADS, and the functional relevance of IDS at 6 and 13 months. While 6âmonthâolds showed a preference for IDS over ADS, 13âmonthâolds did not. Differences in gaze following behavior triggered by speech register (IDS vs. ADS) were found in both age groups. The degree of infantsâ preference for IDS (relative to ADS) was linked to the quality of maternal IDS infants were exposed to. No such relationship was found between gaze following behavior and maternal IDS quality and infantsâ IDS preference. The results speak to a dynamic interaction between infantsâ preference for different kinds of social signals and the social cues available to them
L_(p)-error estimates for radial basis function interpolation on the sphere
In this paper we review the variational approach to radial basis function interpolation on the sphere and establish new Lp-error bounds, for p[1,â]. These bounds are given in terms of a measure of the density of the interpolation points, the dimension of the sphere and the smoothness of the underlying basis function
Trends Shaping Western European Agrifood Systems of the Future
Western Europeâs agrifood systems are highly developed, extremely complex, and dependably produce food for billions. Securing their functionality is imperative whilst dealing with varieties of major challenges and opportunities in the future. Multiple stakeholders are involved in system transitions; therefore, synthesizing views from different scientific disciplines is essential for a robust trend analysis. Through workshops with a variety of experts, extensive research, followed by close monitoring over 5 years, we identified trends that will influence the shape of the evolving agrifood systems. Based on this, we determined which trends need addressing by agrifood research to secure the systemâs future functioning. We detected nine trends with 50 sub-topics that will shape the future of Western European agrifood systems, of which 5 are classified as macro- and 4 as micro-trends. Our second objective was to improve the efforts of the stakeholders in- and outside of the agrifood area to secure functioning and further improvement through giving a comprehensive overview. This contributes to enhanced strategies for sustainable and resilient agrifood systems that produce sufficient affordable nutritious food for a planetary health diet, and hence, supporting successful implementation of selected goals from the 2030 Agenda for Sustainable Development and the European Green Deal
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