scholarly journals A sleep epidemic or enlightenment? A Bayesian approach to test the sleep epidemic hypothesis shows foragers have short and fragmented sleep compared to large scale societies

2020 ◽  
Author(s):  
David R. Samson

AbstractHuman sleep is linked with nearly every aspect of our health and wellbeing. The question whether and to what extent human sleep is in a state of evolutionary mismatch has gained recent attention from both clinical and biological science researchers. Here, I use a comparative Bayesian approach aimed at testing the sleep epidemic hypothesis – the idea that, due to labor demands and technological disruption, sleep-wake activity is negatively impacted in post-industrial, economically developed societies. In contrast to the expectations of the sleep epidemic hypothesis, when compared to both large and small-scale subsistence societies that rely on agriculture for subsistence, foragers were the shortest, least efficient sleeping group. Coupled with previous work demonstrating that foragers have stronger circadian rhythms compared to those sleeping in buffered environments, I present the sleep-rhythm trade-off hypothesis – that sleep duration, quality, and synchrony is driven by trade-offs between sleep security and comfort versus sleep site environmental exposure. One strategy to improve wellbeing of modern sleepers would be to focus on behavioral interventions that reduce desynchronizations of circadian rhythms, while holding the positive ground of safe, secure, and regulated sleep environments typical of economically developed societies.

2010 ◽  
Vol 14 (10) ◽  
pp. 1989-2001 ◽  
Author(s):  
H. Murakami ◽  
X. Chen ◽  
M. S. Hahn ◽  
Y. Liu ◽  
M. L. Rockhold ◽  
...  

Abstract. This study presents a stochastic, three-dimensional characterization of a heterogeneous hydraulic conductivity field within the Hanford 300 Area, Washington, USA, by assimilating large-scale, constant-rate injection test data with small-scale, three-dimensional electromagnetic borehole flowmeter (EBF) measurement data. We first inverted the injection test data to estimate the transmissivity field, using zeroth-order temporal moments of pressure buildup curves. We applied a newly developed Bayesian geostatistical inversion framework, the method of anchored distributions (MAD), to obtain a joint posterior distribution of geostatistical parameters and local log-transmissivities at multiple locations. The unique aspects of MAD that make it suitable for this purpose are its ability to integrate multi-scale, multi-type data within a Bayesian framework and to compute a nonparametric posterior distribution. After we combined the distribution of transmissivities with depth-discrete relative-conductivity profile from the EBF data, we inferred the three-dimensional geostatistical parameters of the log-conductivity field, using the Bayesian model-based geostatistics. Such consistent use of the Bayesian approach throughout the procedure enabled us to systematically incorporate data uncertainty into the final posterior distribution. The method was tested in a synthetic study and validated using the actual data that was not part of the estimation. Results showed broader and skewed posterior distributions of geostatistical parameters except for the mean, which suggests the importance of inferring the entire distribution to quantify the parameter uncertainty.


2018 ◽  
Author(s):  
Marco A. R. Mello ◽  
Gabriel M. Felix ◽  
Rafael B. P. Pinheiro ◽  
Renata L. Muylaert ◽  
Cullen Geiselman ◽  
...  

Introductory paragraphHow are ecological systems assembled? Here, we aim to contribute to answering this question by harnessing the framework of a novel integrative hypothesis. We shed light on the assembly rules of a multilayer network formed by frugivory and nectarivory interactions between bats and plants in the Neotropics. Our results suggest that, at a large scale, phylogenetic trade-offs separate species into different layers and modules. At an intermediate scale, the modules are also shaped by geographic trade-offs. And at a small scale, the network shifts to a nested structure within its modules, probably as a consequence of resource breadth processes. Finally, once the topology of the network is shaped, morphological traits related to consuming fruits or nectar determine which species are central or peripheral. Our results help understand how different processes contribute to the assemblage of ecological systems at different scales, resulting in a compound topology.


2020 ◽  
pp. 1-15
Author(s):  
ALAN S. GERBER ◽  
GREGORY A. HUBER ◽  
ALBERT H. FANG

Abstract Do small wording differences in message-based behavioral interventions have outsized effects on behavior? An influential initial study, examining this question in the domain of political behavior using two small-scale field experiments, argues that subtle linguistic cues in voter mobilization messages describing someone as a voter (noun) instead of one who votes (verb) dramatically increases turnout rates by activating a person's social identity as a voter. Two subsequent large-scale replication field experiments challenged this claim, finding no effect even in electorally competitive settings. However, these experiments may not have reproduced the psychological context needed to motivate behavioral change because they did not occur in highly competitive and highly salient electoral contexts. Addressing this major criticism, we conduct a large-scale, preregistered replication field experiment in the 2016 presidential election. We find no evidence that noun wording increases turnout compared to verb wording in this highly salient electoral context, even in competitive states.


2021 ◽  
Vol 13 (13) ◽  
pp. 7310
Author(s):  
Aicha Ait Sair ◽  
Kamal Kansou ◽  
Franck Michaud ◽  
Bernard Cathala

Biorefineries have many possible designs and therefore, present varied benefits in regards to sustainable development. Evaluating these biorefineries is central for the domain, and, as small-scale biorefineries (SSB) are commonly opposed to the large ones, specifying the concept of scale of a biorefinery is essential as well. However, there is no consensual definition of the “scale”, and the meaning of the term changes with the context. This paper presents a methodology to specify the concept of scale by grouping various biorefineries processing lignocellulosic biomass according to factors related to feedstock, process, economy and mobility of the facility, without any predetermined pattern. Data from 15 operational biorefineries are analyzed using a multivariate analysis combined with a hierarchical clustering. The classification obtained categorizes biorefineries into four design classes: smallest, small, hybrid and large scale. Small-scale biorefineries are characterized by a small investment cost (less than 2 M€), a low processing capacity (less than 100 t/day) and a low process complexity, while the end-products’ added value is variable. The mobility of the plants is a sufficient, but not necessary, criterion to have a small-scale biorefinery. Finally, the designs of the investigated biorefineries can be explained by two main trade-offs: one between the mobility and the processing capacity-investment cost, and the other between the process complexity and the added value.


2010 ◽  
Vol 7 (2) ◽  
pp. 2017-2052 ◽  
Author(s):  
H. Murakami ◽  
X. Chen ◽  
M. S. Hahn ◽  
Y. Liu ◽  
M. L. Rockhold ◽  
...  

Abstract. This study presents a stochastic, three-dimensional characterization of a heterogeneous hydraulic conductivity field within DOE's Hanford 300 Area site, Washington, by assimilating large-scale, constant-rate injection test data with small-scale, three-dimensional electromagnetic borehole flowmeter (EBF) measurement data. We first inverted the injection test data to estimate the transmissivity field, using zeroth-order temporal moments of pressure buildup curves. We applied a newly developed Bayesian geostatistical inversion framework, the method of anchored distributions (MAD), to obtain a joint posterior distribution of geostatistical parameters and local log-transmissivities at multiple locations. The unique aspects of MAD that make it suitable for this purpose are its ability to integrate multi-scale, multi-type data within a Bayesian framework and to compute a nonparametric posterior distribution. After we combined the distribution of transmissivities with depth-discrete relative-conductivity profile from the EBF data, we inferred the three-dimensional geostatistical parameters of the log-conductivity field, using the Bayesian model-based geostatistics. Such consistent use of the Bayesian approach throughout the procedure enabled us to systematically incorporate data uncertainty into the final posterior distribution. The method was tested in a synthetic study and validated using the actual data that was not part of the estimation. Results showed broader and skewed posterior distributions of geostatistical parameters except for the mean, which suggests the importance of inferring the entire distribution to quantify the parameter uncertainty.


2015 ◽  
Vol 12 (112) ◽  
pp. 20150780 ◽  
Author(s):  
A. Bottinelli ◽  
E. van Wilgenburg ◽  
D. J. T. Sumpter ◽  
T. Latty

Transport networks distribute resources and information in many human and biological systems. Their construction requires optimization and balance of conflicting criteria such as robustness against disruptions, transport efficiency and building cost. The colonies of the polydomous Australian meat ant Iridomyrmex purpureus are a striking example of such a decentralized network, consisting of trails that connect spatially separated nests. Here we study the rules that underlie network construction in these ants. We find that a simple model of network growth, which we call the minimum linking model (MLM), is sufficient to explain the growth of real ant colonies. For larger networks, the MLM shows a qualitative similarity with a Euclidean minimum spanning tree, prioritizing cost and efficiency over robustness. We introduce a variant of our model to show that a balance between cost, efficiency and robustness can be also reproduced at larger scales than ant colonies. Remarkably, such a balance is influenced by a parameter reflecting the specific features of the modelled transport system. The extended MLM could thus be a suitable source of inspiration for the construction of cheap and efficient transport networks with non-zero robustness, suggesting possible applications in the design of human-made networks.


2000 ◽  
Vol 45 (4) ◽  
pp. 396-398
Author(s):  
Roger Smith
Keyword(s):  

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Evi Rahmawati ◽  
Irnin Agustina Dwi Astuti ◽  
N Nurhayati

IPA Integrated is a place for students to study themselves and the surrounding environment applied in daily life. Integrated IPA Learning provides a direct experience to students through the use and development of scientific skills and attitudes. The importance of integrated IPA requires to pack learning well, integrated IPA integration with the preparation of modules combined with learning strategy can maximize the learning process in school. In SMP 209 Jakarta, the value of the integrated IPA is obtained from 34 students there are 10 students completed and 24 students are not complete because they get the value below the KKM of 68. This research is a development study with the development model of ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The use of KPS-based integrated IPA modules (Science Process sSkills) on the theme of rainbow phenomenon obtained by media expert validation results with an average score of 84.38%, average material expert 82.18%, average linguist 75.37%. So the average of all aspects obtained by 80.55% is worth using and tested to students. The results of the teacher response obtained 88.69% value with excellent criteria. Student responses on a small scale acquired an average score of 85.19% with highly agreed criteria and on the large-scale student response gained a yield of 86.44% with very agreed criteria. So the module can be concluded receiving a good response by the teacher and students.


2019 ◽  
Vol 61 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Loretta Lees

Abstract Gentrification is no-longer, if it ever was, a small scale process of urban transformation. Gentrification globally is more often practised as large scale urban redevelopment. It is state-led or state-induced. The results are clear – the displacement and disenfranchisement of low income groups in favour of wealthier in-movers. So, why has gentrification come to dominate policy making worldwide and what can be done about it?


2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Bùi Thị Bích Lan

In Vietnam, the construction of hydropower projects has contributed significantly in the cause of industrialization and modernization of the country. The place where hydropower projects are built is mostly inhabited by ethnic minorities - communities that rely primarily on land, a very important source of livelihood security. In the context of the lack of common productive land in resettlement areas, the orientation for agricultural production is to promote indigenous knowledge combined with increasing scientific and technical application; shifting from small-scale production practices to large-scale commodity production. However, the research results of this article show that many obstacles in the transition process are being posed such as limitations on natural resources, traditional production thinking or the suitability and effectiveness of scientific - technical application models. When agricultural production does not ensure food security, a number of implications for people’s lives are increasingly evident, such as poverty, preserving cultural identity, social relations and resource protection. Since then, it has set the role of the State in researching and building appropriate agricultural production models to exploit local strengths and ensure sustainability.


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