Calcareous nannoplankton ecology and community change across the Paleocene-Eocene Thermal Maximum

The Paleocene-Eocene Thermal Maximum (PETM; ca. 55.8 Ma) is thought to coincide with a profound but entirely transient change among nannoplankton communities throughout the ocean. Here we explore the ecology of nannoplankton during the PETM by using multivariate analyses of a global data set that is based upon the distribution of taxa in time and space. We use these results, coupled with stable isotope data and geochemical modeling, to reinterpret the ecology of key genera. The results of the multivariate analyses suggest that the community was perturbed significantly in coastal and high-latitudes sites compared to the open ocean, and the relative influence of temperature and nutrient availability on the assemblage varies regionally. The open ocean became more stratified and less productive during the PETM and the oligotrophic assemblage responded primarily to changes in nutrient availability. Alternatively, assemblages at the equator and in the Southern Ocean responded to temperature more than to nutrient reduction. In addition, the assemblage change at the PETM was not merely transient—there is evidence of adaptation and a long-term change in the nannoplankton community that persists after the PETM and results in the disappearance of a high-latitude assemblage. The long-term effect on communities caused by transient warming during the PETM has implications for modern-day climate change, suggesting similar permanent changes to nannoplankton community structure as the oceans warm.

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Long-term change in the prevalence of intimate partner violence: a 20-year follow-up study in León, Nicaragua, 1995-2016

BMJ Global Health ◽

10.1136/bmjgh-2020-002339 ◽

2020 ◽

Vol 5 (4) ◽

pp. e002339 ◽

Cited By ~ 2

Author(s):

Mary Ellsberg ◽

William Ugarte ◽

Junior Ovince ◽

Alexandra Blackwell ◽

Margarita Quintanilla

Keyword(s):

Intimate Partner Violence ◽

Partner Violence ◽

Intimate Partner ◽

Access To Justice ◽

Data Set ◽

Time Period ◽

Term Change ◽

Significant Difference ◽

Demographic Shifts

IntroductionAlthough intimate partner violence (IPV) affects an estimated one out of three women globally, evidence on violence prevention is still scarce. No studies have measured long-term change in larger populations over a prolonged period.MethodsThe aim of this study was to measure changes in the prevalence of IPV in León, Nicaragua, between 1995 and 2016. The 2016 study interviewed 846 ever-partnered women aged 15 to 49 regarding experiences of physical, sexual and emotional IPV. These findings were analysed together with comparable data collected from 354 women in 1995. Multivariate logistic regression modelling was carried out on a pooled data set to identify differences between the two studies while controlling for potential confounding factors.ResultsLifetime physical IPV decreased from 54.8 to 27.6 per cent (adjusted OR (AOR) 0.37; 95% CI 0.28 to 0.49) and 12-month prevalence of physical IPV decreased from 28.2 to 8.3 per cent (AOR 0.29; 95% CI 0.20 to 0.42), respectively. Similar decreases were found in lifetime and 12-month emotional IPV. No significant difference was found in the prevalence of lifetime sexual violence between the two time periods.ConclusionsThe results suggest that the reduction in IPV was not due to demographic shifts, such as increased education or age, but reflects a true decrease in the prevalence of IPV. The decrease is not likely to have occurred on its own, and may be attributable to multisectoral efforts by the Nicaraguan government, international donors and the Nicaraguan women’s movement to increase women’s knowledge of their rights, as well as access to justice and services for survivors during this time period.

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The role of open ocean boundary forcing on seasonal to decadal-scale variability and long-term change of natural shelf hypoxia

Environmental Research Letters ◽

10.1088/1748-9326/6/2/025002 ◽

2011 ◽

Vol 6 (2) ◽

pp. 025002 ◽

Cited By ~ 23

Author(s):

Pedro M S Monteiro ◽

Boris Dewitte ◽

Mary I Scranton ◽

Aurélien Paulmier ◽

Anja K van der Plas

Keyword(s):

Open Ocean ◽

Term Change ◽

Decadal Scale ◽

Ocean Boundary

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Long-term community change through multiple rapid transitions in a desert rodent community

10.1101/163931 ◽

2017 ◽

Author(s):

Erica M. Christensen ◽

David J. Harris ◽

S. K. Morgan Ernest

Keyword(s):

Latent Dirichlet Allocation ◽

Community Change ◽

Priority Effects ◽

Point Model ◽

Term Change ◽

Desert Rodent ◽

Change Point Model ◽

Rodent Community ◽

Climate Events

AbstractWhile studies increasingly document long-term change in community composition, whether long-term change occurs gradually or via rapid reorganization events remains unclear. We used Latent Dirichlet Allocation (LDA) and a change-point model to examine the long-term dynamics of a desert rodent community undergoing compositional change over a 38-year span. Our approach detected three rapid reorganization events, where changes in the relative abundances of dominant and rare species occurred, and a separate period of increased variance in the structure of the community. These events coincided with time periods—possibly related to climate events—where the total abundance of rodents was extremely low. There are a variety of processes that could link low abundance events with a higher probability of rapid ecological transitions, including higher importance of stochastic processes (i.e., competitive interactions or priority effects) and the removal of structuring effects of competitive dominants or incumbent species. Continued study of the dynamics of community change will provide important information not only on the processes structuring communities, but will also provide guidance for forecasting how communities will undergo change in the future.

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Vivid Imagers Are Better at Detecting Salient Changes

Journal of Individual Differences ◽

10.1027/1614-0001.27.4.218 ◽

2006 ◽

Vol 27 (4) ◽

pp. 218-228 ◽

Cited By ~ 13

Author(s):

Paul Rodway ◽

Karen Gillies ◽

Astrid Schepman

Keyword(s):

Individual Differences ◽

Change Detection ◽

Visual Imagery ◽

Detection Task ◽

Level Of Detail ◽

Detection Accuracy ◽

Change Detection Task ◽

Term Change ◽

High Level

This study examined whether individual differences in the vividness of visual imagery influenced performance on a novel long-term change detection task. Participants were presented with a sequence of pictures, with each picture and its title displayed for 17 s, and then presented with changed or unchanged versions of those pictures and asked to detect whether the picture had been changed. Cuing the retrieval of the picture's image, by presenting the picture's title before the arrival of the changed picture, facilitated change detection accuracy. This suggests that the retrieval of the picture's representation immunizes it against overwriting by the arrival of the changed picture. The high and low vividness participants did not differ in overall levels of change detection accuracy. However, in replication of Gur and Hilgard (1975) , high vividness participants were significantly more accurate at detecting salient changes to pictures compared to low vividness participants. The results suggest that vivid images are not characterised by a high level of detail and that vivid imagery enhances memory for the salient aspects of a scene but not all of the details of a scene. Possible causes of this difference, and how they may lead to an understanding of individual differences in change detection, are considered.

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