1,082 research outputs found
Next steps for understanding the selective relevance of female-female competition
After decades of neglect, recent empirical
research on exaggerated female traits
(e.g., ornaments, armaments, aggression,
acoustic signals, etc.) has revived interest
in this widespread but poorly understood
phenomenon, and shown that these traits
often function in the context of female-female
competition (West-Eberhard,
1983; Amundsen, 2000; Clutton-Brock,
2009; Rosvall, 2011a; Stockley and Bro-Jørgensen,
2011; Rubenstein, 2012 [Theme
issue]; Stockley and Campbell, 2013
[Theme issue]). However, recent reviews
have emphasized the applicability of sexual
vs. social selection, rather than rigorously
examining the role of different ecological
contexts in shaping the evolution of traits
used in competitive contexts (hereafter,
“competitive traits”) in females. Thus,
we still lack a solid understanding of
the ecological and evolutionary mechanisms
driving the evolution of female trait
expression, in particular whether, how,
and why these mechanisms vary among
species, and between the sexes
Amniotic Fluid Ingestion Enhances\ud Opioid-Mediated But Not\ud Nonopioid-Mediated Analgesia
Ingestion of amniotic fluid or placenta by rats has been shown to enhance several types of opioid-mediated analgesia: that induced by morphine, footshock, vaginal/cervical stimulation, and late pregnancy. This enhancement has also been blocked by administration of opioid antagonists. The present study was designed to examine further the specificity of the enhancement effect for opioid-mediated analgesia by testing for enhancement following administration of aspirin, a nonopioid analgesic. The formalin test was used as the pain threshold assay. Amniotic fluid or beef bouillon was administered by orogastric tube to rats that were treated either with morphine sulfate or saline. or pretreated with naltrexone, then treated with aspirin or vehicle. Both morphine and aspirin treatments produced analgesia. Amniotic fluid significantly enhanced the analgesia produced by morphine, but did not enhance the analgesia produced by aspirin, further suggesting that the enhancing effect of amniotic fluid ingestion is specific for opioid-mediated analgesia, such as that existing at the start of parturition
Effects of hypothalamic knife cuts and experience on maternal behavior in the rat
Recent investigations suggest that the disruption of placentophagia, pup-directed maternal behavior, and nestbuilding seen after lesions of the medial preoptic area (MPO) or the lateral hypothalamus may be due to the interruption at different points of a single longitudinal neural system mediating these behaviors. To test this, we compared the effects of knife cuts on the lateral border of the MPO, and of the posterior medial forebrain bundle (MFB), with asymmetrical cuts combining a unilateral MPO cut with a contralateral MFB cut. We observed placentophagia, nestbuilding, and pup-directed maternal behaviors at, and after, parturition in both primiparous and biparous rats. In primiparae, MPO cuts (a) disrupted placentophagia, (b) delayed the onset of crouching and pup-licking, and (c) eliminated retrieval and nestbuilding. Asymmetrical cuts (a) disrupted placentophagia, and (b) delayed the onset of maternal behavior. In biparous rats, MPO cuts eliminated nestbuilding and retrieval. MFB cuts (a) disrupted placentophagia, and (b) eliminated nestbuilding. Asymmetrical cuts (a) delayed nestbuilding. These results suggest the involvement of a longitudinal neural system in the production of immediate pup-directed maternal behavior, placentophagia, and nestbuilding in parturient primiparae, but which is not critical for the eventual display of maternal behavior and nestbuilding in maternally naive rats, nor for the immediate onset of placentophagia and maternal behavior in maternally experienced rats
Recommended from our members
The Effect of Flowrate on Trapping in a Two-phase System as it Relates to CO₂ Sequestration
This research examines the independent and combined effects of drainage and imbibition flowrate on nonwetting phase capillary trapping in a two-phase, porous medium system. A uniform system of cubic arrangement and non-uniform systems of both cubic and rhombohedral arrangements were examined in order to analyze and compare the nonwetting phase trapping trends between uniform and non-uniform porous media. The unique system set-up, composed of similar refractive indexes of the wetting phase and medium, allows flow experiments to be performed in 3-D printed bead packs (of different arrangements) (44.8x44.8x2.8mm) and quantified with 2-D images. All beads are 700μm in diameter, comparable to the grain size of a sandstone. Soltrol and water (proxy fluids for brine and supercritical CO₂) were used in flow experiments. For the uniform cubic arrangement, it was found that slower drainage flowrates, regardless of the subsequent imbibition flowrate, resulted in the largest amount of nonwetting phase trapped in comparison to higher drainage flowrates. Slow drainages correspond to a capillary dominated flow regime and greater disconnect of the nonwetting phase post-drainage, both of which are found to be conducive to nonwetting phase trapping. However, increasing non- uniformity (or the introduction of high porosity zones) in a cubic bead pack was observed to alter this trend, while trends determined by the uniform cubic arrangement were also observed on the non-uniform rhombohedral bead pack. It is therefore suggested that drainage flowrate (scCO₂ injection) and a system’s uniformity (formation heterogeneity) be considered in order to favorably influence trapping efficiency in scCO₂ injection schemes
Detecting Urban Emissions Changes and Events With a Near‐Real‐Time‐Capable Inversion System
In situ observing networks are increasingly being used to study greenhouse gas emissions in urban environments. While the need for sufficiently dense observations has often been discussed, density requirements depend on the question posed and interact with other choices made in the analysis. Focusing on the interaction of network density with varied meteorological information used to drive atmospheric transport, we perform geostatistical inversions of methane flux in the South Coast Air Basin, California, in 2015–2016 using transport driven by a locally tuned Weather Research and Forecasting configuration as well as by operationally available meteorological products. We find total‐basin flux estimates vary by as much as a factor of two between inversions, but the spread can be greatly reduced by calibrating the estimates to account for modeled sensitivity. Using observations from the full Los Angeles Megacities Carbon Project observing network, inversions driven by low‐resolution generic wind fields are robustly sensitive (p < 0.05) to seasonal differences in methane flux and to the increase in emissions caused by the 2015 Aliso Canyon natural gas leak. When the number of observing sites is reduced, the basin‐wide sensitivity degrades, but flux events can be detected by testing for changes in flux variance, and even a single site can robustly detect basin‐wide seasonal flux variations. Overall, an urban monitoring system using an operational methane observing network and off‐the‐shelf meteorology could detect many seasonal or event‐driven changes in near real time—and, if calibrated to a model chosen as a transfer standard, could also quantify absolute emissions.Key PointsLA CH4 flux estimates differ by driving meteorology but agree when calibrated for model sensitivityAliso Canyon leak can be detected by inversions using operational meteorologyOperational meteorology driven inversions significantly detect seasonal emission changes even with only one sitePeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149534/1/jgrd55279-sup-0001-Text_SI-S01.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149534/2/jgrd55279.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149534/3/jgrd55279_am.pd
Signing at the beginning versus at the end does not decrease dishonesty
Honest reporting is essential for society to function well. However, people frequently lie when asked to provide information, such as misrepresenting their income to save money on taxes. A landmark finding published in PNAS [L. L. Shu, N. Mazar, F. Gino, D. Ariely, M. H. Bazerman, *Proc. Natl. Acad. Sci. USA.* 109, 15197–15200
(2012)] provided evidence for a simple way of encouraging honest reporting: asking people to sign a veracity statement at the beginning instead of at the end of a self-report form. Since this finding was published, various government agencies have adopted this practice.
However, in this project, we failed to replicate this result. Across five conceptual replications (*n* = 4,559) and one highly powered, preregistered, direct replication (*n* = 1,235) conducted with the authors of the original paper, we observed no effect of signing first on honest reporting. Given the policy applications of this result, it is important to update the scientific record regarding the veracity of these results
Recommended from our members
In utero ultrafine particulate matter exposure causes offspring pulmonary immunosuppression.
Early life exposure to fine particulate matter (PM) in air is associated with infant respiratory disease and childhood asthma, but limited epidemiological data exist concerning the impacts of ultrafine particles (UFPs) on the etiology of childhood respiratory disease. Specifically, the role of UFPs in amplifying Th2- and/or Th17-driven inflammation (asthma promotion) or suppressing effector T cells (increased susceptibility to respiratory infection) remains unclear. Using a mouse model of in utero UFP exposure, we determined early immunological responses to house dust mite (HDM) allergen in offspring challenged from 0 to 4 wk of age. Two mice strains were exposed throughout gestation: C57BL/6 (sensitive to oxidative stress) and BALB/C (sensitive to allergen exposure). Offspring exposed to UFPs in utero exhibited reduced inflammatory response to HDM. Compared with filtered air (FA)-exposed/HDM-challenged mice, UFP-exposed offspring had lower white blood cell counts in bronchoalveolar lavage fluid and less pronounced peribronchiolar inflammation in both strains, albeit more apparent in C57BL/6 mice. In the C57BL/6 strain, offspring exposed in utero to FA and challenged with HDM exhibited a robust response in inflammatory cytokines IL-13 and Il-17. In contrast, this response was lost in offspring exposed in utero to UFPs. Circulating IL-10 was significantly up-regulated in C57BL/6 offspring exposed to UFPs, suggesting increased regulatory T cell expression and suppressed Th2/Th17 response. Our results reveal that in utero UFP exposure at a level close to the WHO recommended PM guideline suppresses an early immune response to HDM allergen, likely predisposing neonates to respiratory infection and altering long-term pulmonary health
How Methods for Navigating Uncertainty Connect Science and Policy at the Water-Energy-Food Nexus
As the water-energy-food (WEF) nexus becomes an increasingly common framework for bridging science and policy, there is a growing need to unpack and make explicit many of the methods and assumptions being used to operationalize the nexus. In this paper, we focus on two common approaches to nexus research, quantitative modeling and futures thinking, and the ways that each set of methodological tools address uncertainty. We first review the underlying assumptions of each approach with a focus on sources of and ability to measure uncertainty, and potential complementarities. Quantitative modeling takes a probabilistic approach to predicting the likelihood of a specific outcome or future state based on estimates of current system dynamics. In contrast, futures thinking approaches, such as scenario processes, explore novel changes that cannot be fully predicted or even anticipated based on current understandings of the nexus. We then examine a set of applied nexus projects that bridge science and policy-making contexts to better understand practitioner experiences with different methodological tools and how they are utilized to navigate uncertainty. We explore one nexus case study, LIVES Cambodia, in-depth, to better understand the opportunities and challenges associated with participatory modeling and stakeholder engagement with uncertainty in a policy-making context. Across the cases, practitioners identify the complementarity between modeling and futures thinking approaches, and those projects that integrated both into the planning process experienced benefits from having multiple angles on uncertainty within the nexus. In particular, stakeholder engagement provided critical opportunities to address some types of uncertainties (e.g., data gaps) through the use of local knowledge. Explicit discussions of model uncertainty and use of scenario processes also enabled stakeholders to deepen their understandings of uncertainties and envision policy pathways that would be robust to uncertainty. In many senses, models became boundary objects that encouraged critical thinking and questioning of assumptions across diverse stakeholders. And, for some nexus projects, confronting uncertainty in explicit and transparent ways build capacity for policy flexibility and adaptiveness. We conclude with a discussion of when and how these benefits can be fully realized through the strategic use of appropriate approaches to characterizing and navigating nexus uncertainty
- …