scholarly journals Group-level patterns emerge from individual speed as revealed by an extremely social robotic fish

2020 ◽  
Author(s):  
Jolle W. Jolles ◽  
Nils Weimar ◽  
Tim Landgraf ◽  
Pawel Romanczuk ◽  
Jens Krause ◽  
...  
Keyword(s):  
Empirical Work ◽  
Feedback System ◽  
Robotic Fish ◽  
Collective Behaviour ◽  
Movement Speed ◽  
Group Level ◽  
Individual Based Models ◽  
Biomimetic Robot ◽  
Induced Changes

AbstractUnderstanding the emergence of collective behaviour has long been a key research focus in the natural sciences. Besides the fundamental role of social interaction rules, a combination of theoretical and empirical work indicates individual speed may be a key process that drives the collective behaviour of animal groups. Socially-induced changes in speed by interacting animals make it difficult to isolate the effects of individual speed on group-level behaviours. Here we tackled this issue by pairing guppies with a biomimetic robot. We used a closed-loop tracking and feedback system to let a robotic fish naturally interact with a live partner in real time, and programmed it to strongly copy and follow its partner’s movements while lacking any preferred movement speed or directionality of its own. We show that individual differences in guppies’ movement speed were highly repeatable and shaped key collective patterns: higher individual speeds resulted in stronger leadership, lower cohesion, higher alignment, and better temporal coordination in the pairs. By combining the strengths of individual-based models and observational work with state-of-the-art robotics, we provide novel evidence that individual speed is a key, fundamental process in the emergence of collective behaviour.

scholarly journals Group-level patterns emerge from individual speed as revealed by an extremely social robotic fish

2020 ◽  
Vol 16 (9) ◽  
pp. 20200436
Author(s):  
Jolle W. Jolles ◽  
Nils Weimar ◽  
Tim Landgraf ◽  
Pawel Romanczuk ◽  
Jens Krause ◽  
...  
Keyword(s):  
Empirical Work ◽  
Feedback System ◽  
Robotic Fish ◽  
Collective Behaviour ◽  
Movement Speed ◽  
Group Level ◽  
Individual Based Models ◽  
Biomimetic Robot ◽  
Induced Changes

Understanding the emergence of collective behaviour has long been a key research focus in the natural sciences. Besides the fundamental role of social interaction rules, a combination of theoretical and empirical work indicates individual speed may be a key process that drives the collective behaviour of animal groups. Socially induced changes in speed by interacting animals make it difficult to isolate the effects of individual speed on group-level behaviours. Here, we tackled this issue by pairing guppies with a biomimetic robot. We used a closed-loop tracking and feedback system to let a robotic fish naturally interact with a live partner in real time, and programmed it to strongly copy and follow its partner's movements while lacking any preferred movement speed or directionality of its own. We show that individual differences in guppies' movement speed were highly repeatable and in turn shaped key collective patterns: a higher individual speed resulted in stronger leadership, lower cohesion, higher alignment and better temporal coordination of the pairs. By combining the strengths of individual-based models and observational work with state-of-the-art robotics, we provide novel evidence that individual speed is a key, fundamental process in the emergence of collective behaviour.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Cannabinoid-induced changes in the immune system: The role of microRNAs

2021 ◽  
Vol 98 ◽  
pp. 107832
Author(s):  
Hirva K. Bhatt ◽  
Dana Song ◽  
Gyen Musgrave ◽  
P.S.S. Rao
Keyword(s):  
Immune System ◽  
Induced Changes

scholarly journals Space Radiation-Induced Alterations in the Hippocampal Ubiquitin-Proteome System

2021 ◽  
Vol 22 (14) ◽  
pp. 7713
Author(s):  
Alyssa Tidmore ◽  
Sucharita M. Dutta ◽  
Arriyam S. Fesshaye ◽  
William K. Russell ◽  
Vania D. Duncan ◽  
...  
Keyword(s):  
Spatial Memory ◽  
Memory Performance ◽  
Space Radiation ◽  
Label Free ◽  
Proteomic Profiling ◽  
Neurocognitive Deficits ◽  
Male Wistar Rats ◽  
Radiation Induced ◽  
Induced Changes

Exposure of rodents to <20 cGy Space Radiation (SR) impairs performance in several hippocampus-dependent cognitive tasks, including spatial memory. However, there is considerable inter-individual susceptibility to develop SR-induced spatial memory impairment. In this study, a robust label-free mass spectrometry (MS)-based unbiased proteomic profiling approach was used to characterize the composition of the hippocampal proteome in adult male Wistar rats exposed to 15 cGy of 1 GeV/n 48Ti and their sham counterparts. Unique protein signatures were identified in the hippocampal proteome of: (1) sham rats, (2) Ti-exposed rats, (3) Ti-exposed rats that had sham-like spatial memory performance, and (4) Ti-exposed rats that impaired spatial memory performance. Approximately 14% (159) of the proteins detected in hippocampal proteome of sham rats were not detected in the Ti-exposed rats. We explored the possibility that the loss of the Sham-only proteins may arise as a result of SR-induced changes in protein homeostasis. SR-exposure was associated with a switch towards increased pro-ubiquitination proteins from that seen in Sham. These data suggest that the role of the ubiquitin-proteome system as a determinant of SR-induced neurocognitive deficits needs to be more thoroughly investigated.

The Influence of Incubator and Accelerator Participation on Nanotechnology Venture Success

2021 ◽  
pp. 104225872110245
Author(s):  
Jennifer L. Woolley ◽  
Nydia MacGregor
Keyword(s):  
Venture Capital ◽  
Empirical Work ◽  
Development Program ◽  
Development Programs ◽  
Government Grants ◽  
Recent Growth ◽  
Using Data

This study investigates how venture development programs such as private incubators, university incubators, and accelerators influence the success of participating nanotechnology startups. With the recent growth in such programs, empirical work is needed to compare their impact on participants across programs and with nonparticipants. Using data on firm bankruptcies, liquidation, government grants, and venture capital, we find benefits, but the influence of each venture development program varies greatly. We further investigate the influence of program services and resources to clarify program heterogeneity beyond existing typologies. The results clarify the role of these programs and ecosystem intermediaries.

scholarly journals The role of race, religion, and partisanship in misperceptions about COVID-19

2021 ◽  
Vol 24 (4) ◽  
pp. 638-657
Author(s):  
James N. Druckman ◽  
Katherine Ognyanova ◽  
Matthew A. Baum ◽  
David Lazer ◽  
Roy H. Perlis ◽  
...  
Keyword(s):  
Lived Experiences ◽  
Media Exposure ◽  
Group Level ◽  
Political Issues ◽  
The Public ◽  
Media Usage ◽  
Targeted Interventions ◽  
Large Survey ◽  
Racial Ethnic

Concerns about misperceptions among the public are rampant. Yet, little work explores the correlates of misperceptions in varying contexts – that is, how do factors such as group affiliations, media exposure, and lived experiences correlate with the number of misperceptions people hold? We address these questions by investigating misperceptions about COVID-19, focusing on the role of racial/ethnic, religious, and partisan groups. Using a large survey, we find the number of correct beliefs held by individuals far dwarfs the number of misperceptions. When it comes to misperceptions, we find that minorities, those with high levels of religiosity, and those with strong partisan identities – across parties – hold a substantially greater number of misperceptions than those with contrasting group affiliations. Moreover, we show other variables (e.g., social media usage, number of COVID-19 cases in one’s county) do not have such strong relationships with misperceptions, and the group-level results do not reflect acquiescence to believing any information regardless of its truth value. Our results accentuate the importance of studying group-level misperceptions on other scientific and political issues and developing targeted interventions for these groups.

scholarly journals The Effect of Dual Language Activation on L2-Induced Changes in L1 Speech within a Code-Switched Paradigm

Languages ◽  
2021 ◽  
Vol 6 (3) ◽  
pp. 114
Author(s):  
Ulrich Reubold ◽  
Sanne Ditewig ◽  
Robert Mayr ◽  
Ineke Mennen
Keyword(s):  
Dual Language ◽  
Native Speakers ◽  
Predictor Variable ◽  
Predictor Variables ◽  
Acoustic Measures ◽  
Before And After ◽  
Language Activation ◽  
Dual Activation ◽  
Induced Changes

The present study sought to examine the effect of dual language activation on L1 speech in late English–Austrian German sequential bilinguals, and to identify relevant predictor variables. To this end, we compared the English speech patterns of adult migrants to Austria in a code-switched and monolingual condition alongside those of monolingual native speakers in England in a monolingual condition. In the code-switched materials, German words containing target segments known to trigger cross-linguistic interaction in the two languages (i.e., [v–w], [ʃt(ʁ)-st(ɹ)] and [l-ɫ]) were inserted into an English frame; monolingual materials comprised English words with the same segments. To examine whether the position of the German item affects L1 speech, the segments occurred either before the switch (“He wants a Wienerschnitzel”) or after (“I like Würstel with mustard”). Critical acoustic measures of these segments revealed no differences between the groups in the monolingual condition, but significant L2-induced shifts in the bilinguals’ L1 speech production in the code-switched condition for some sounds. These were found to occur both before and after a code-switch, and exhibited a fair amount of individual variation. Only the amount of L2 use was found to be a significant predictor variable for shift size in code-switched compared with monolingual utterances, and only for [w]. These results have important implications for the role of dual activation in the speech of late sequential bilinguals.

Nitric oxide decreases lung liquid production via guanosine 3′,5′-cyclic monophosphate

2001 ◽  
Vol 280 (5) ◽  
pp. L923-L929 ◽  
Author(s):  
James J. Cummings ◽  
Huamei Wang
Keyword(s):  
Nitric Oxide ◽  
Pulmonary Epithelium ◽  
Fetal Sheep ◽  
Cgmp Analog ◽  
Pulmonary Arterial ◽  
Series Of Experiments ◽  
Lung Liquid ◽  
Tracer Dilution ◽  
Induced Changes

We studied the role of cGMP in nitric oxide (NO)-induced changes in lung liquid production ( J v ) in chronically instrumented fetal sheep. Forty-five studies were done in which J v was measured by a tracer dilution technique. Left pulmonary arterial flow (Qlpa) was measured by a Doppler flow probe. There were two series of experiments. In the first, we gave 8-bromo-cGMP, a cGMP analog, by either the pulmonary vascular or intraluminal route; in the second, we used agents to inhibit or enhance endogenous cGMP activity. When infused directly into the pulmonary circulation, 8-bromo-cGMP significantly increased Qlpa but had no effect on J v. Conversely, when instilled into the lung liquid, 8-bromo-cGMP had no effect on Qlpa but significantly reduced J v. Inhibition of guanylate cyclase activity with methylene blue totally blocked, whereas phosphodiesterase inhibition with Zaprinast significantly enhanced, the effect of instilled NO on J v. Thus the reduction in lung liquid caused by NO appears to be mediated by cGMP, perhaps through a direct effect on the pulmonary epithelium.

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