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Δευτέρα 10 Σεπτεμβρίου 2018

Loss of Biodiversity Dimensions through Shifting Climates and Ancient Mass Extinctions

Abstract
Many aspects of climate affect the deployment of biodiversity in time and space, and so changes in climate might be expected to drive regional and global extinction of both taxa and their ecological functions. Here we examine the association of past climate changes with extinction in marine bivalves, which are increasingly used as a model system for macroecological and macroevolutionary analysis. Focusing on the Cenozoic Era (66 Myr ago to the present), we analyze extinction patterns in shallow-water marine bivalve genera relative to temperature dynamics as estimated from isotopic data in microfossils. When the entire Cenozoic timeseries is considered, extinction intensity is not significantly associated with the mean temperature or the detrended variance in temperature within a given time interval (stratigraphic stage). However, extinction increases significantly with both the rate of temperature change within the stage of extinction and the absolute change in mean temperature from the preceding stage to the stage of extinction. Thus, several extinction events, particularly the extinction pulse near the Pliocene–Pleistocene boundary, do appear to have climatic drivers. Further, the latitudinal diversity gradient today and the Cenozoic history of polar faunas suggest that long-term, regional extinctions associated with cooling removed not just taxa but a variety of ecological functions from high-latitude seas. These dynamics of biodiversity loss contrast with the two mass extinctions bracketing the Mesozoic Era, which had negligible effects on the diversity of ecological functions despite removing nearly as many taxa as the latitudinal gradient does today. Thus, the fossil record raises a key issue: whether the biotic consequences of present-day stresses will more closely resemble the long-term effects of past climate changes or those that cascaded from the mass extinctions.

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Where Animation and Science Meet

Synopsis
Animation is the collision of art and science. How does an animation studio like DreamWorks Animation use scientific principles and engage in science education to make our films better? By facilitating scientific master-classes, demos, and lectures we give our creators a fundamental understanding of reality that enables them to create the animation caricature known as the Illusion of Life. We leverage principles of biology and physics to create believable performances. I will share insights about our custom programming such as master-classes on Quadruped Anatomy and Flight and how these result in a better image on screen. Conversely, animators offer storytelling tools to the scientific community. Animators often use visualization tools similar to those that many scientists use, but in differing narrative orders and with budgets often far exceeding those of scientists. I will highlight strategies of presentation enhancing understanding and increasing the speed of building bridges to share information with the public. This can help scientists leverage their own scientific principles as they present the importance and excitement of their work to the public, as well as to one another.

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In Vitro Differentiation of Mouse Granulocyte-macrophage-colony-stimulating Factor (GM-CSF)-producing T Helper (THGM) Cells

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Here, we present a protocol to differentiate murine granulocyte-macrophage-colony-stimulating-factor-producing T helper (THGM) cells from naive CD4+ T cells, including isolation of naive CD4+ T cells, differentiation of THGM, and analysis of differentiated THGM cells. This method can be applied to studies of the regulation and function of THGM cells.

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Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods

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We describe a system that utilizes three methods to evaluate the safety and effectiveness of placenta-targeted drug delivery: in vivo imaging to monitor nanoparticle accumulation, high-frequency ultrasound to monitor placental and fetal development, and HPLC to quantify drug delivery to tissue.

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Operant Protocols for Assessing the Cost-benefit Analysis During Reinforced Decision Making by Rodents

A cost-benefit analysis is a weighing-scale approach that the brain performs during the course of decision making. Here, we propose a protocol to train rats on an operant-based decision-making paradigm where rats choose higher rewards at the expense of waiting for 15 s to receive them.

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You Probably Made a Better First Impression Than You Think

After we have conversations with new people, our conversation partners like us and enjoy our company more than we think, according to findings published in Psychological Science, a journal of the Association for Psychological Science.

In our social lives, we're constantly engaged in what researchers call "meta-perception," or trying to figure out how other people see us. Do people think we're boring or interesting, selfish or altruistic, attractive or not?

"Our research suggests that accurately estimating how much a new conversation partner likes us—even though this a fundamental part of social life and something we have ample practice with—is a much more difficult task than we imagine," explain first authors Erica Boothby, a postdoctoral researcher at Cornell University, and Gus Cooney, a postdoctoral researcher at Harvard University.

"We call this a 'liking gap,' and it can hinder our ability to develop new relationships," study coauthor Margaret S. Clark, the John M. Musser Professor of Psychology at Yale University, told Yale News.

Boothby, Cooney, Clark, and Gillian M. Sandstrom, Professor of Psychology at the University of Essex, examined various aspects of the liking gap in a series of five studies.

In one study, the researchers paired participants who had not met before and tasked them with having a 5-minute conversation featuring typical icebreaker questions (e.g., Where are you from? What are your hobbies?). At the end of the conversation, the participants answered questions that gauged how much they liked their conversation partner and how much they thought their conversation partner liked them.

On average, the ratings showed that participants liked their partner more than they thought their partner liked them. Since it can't logically be the case that both people in a conversation like their partner more than their partner likes them, this disparity in average ratings suggests that participants tended to make an estimation error. Indeed, analyses of video recordings suggested that participants were not accounting for their partner's behavioral signals indicating interest and enjoyment.

In a separate study, participants reflected on the conversations they'd just had — according to their ratings, they believed that the salient moments that shaped their partner's thoughts about them were more negative than the moments that shaped their own thoughts about their partner.

"They seem to be too wrapped up in their own worries about what they should say or did say to see signals of others' liking for them, which observers of the conservations see right away," Clark noted.

Additional studies showed that the liking gap emerged regardless of whether people had longer conversations or had conversations in real-world settings. And a study of actual college roommates showed that the liking gap was far from fleeting, enduring over several months.

The phenomenon is interesting because it stands in contrast with the well-established finding that we generally view ourselves more positively than we do others, whether we're thinking about our driving skills, our intelligence, or our chance of experiencing negative outcomes like illness or divorce.

"The liking gap works very differently. When it comes to social interaction and conversation, people are often hesitant, uncertain about the impression they're leaving on others, and overly critical of their own performance," say Boothby and Cooney. "In light of people's vast optimism in other domains, people's pessimism about their conversations is surprising."

The researchers hypothesize that this difference may come down to the context in which we make these self-assessments. When there is another person involved, such as a conversation partner, we may be more cautious and self-critical than in situations when we are rating our own qualities with no other source of input.

"We're self-protectively pessimistic and do not want to assume the other likes us before we find out if that's really true," Clark said.

This self-monitoring may prevent us from pursuing relationships with others who truly do like us.

"As we ease into new neighborhood, build new friendships, or try to impress new colleagues, we need to know what other people think of us," Boothby and Cooney explain. "Any systematic errors we make might have a big impact on our personal and professional lives."

This work was supported by the Templeton Foundation and the Economic and Social Research Council (United Kingdom).

All data have been made publicly available via the Open Science Framework. The complete Open Practices Disclosure for this article is available online. This article has received the badge for Open Data.



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Fifteen Genetic Determinants of Fracture Identified

MONDAY, Sept. 10, 2018 -- Fifteen genetic determinants of fracture, which are also associated with bone mineral density, have been identified, according to a meta-analysis of genome-wide association studies (GWAS) published online Aug. 29 in the...

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