scholarly journals Back to the bones: do muscle area assessment techniques predict functional evolution across a macroevolutionary radiation?

2021 ◽  
Vol 18 (180) ◽  
pp. 20210324
Author(s):  
Karl T. Bates ◽  
Linjie Wang ◽  
Matthew Dempsey ◽  
Sarah Broyde ◽  
Michael J. Fagan ◽  
...  
Keyword(s):  
Large Scale ◽  
Functional Performance ◽  
Muscle Size ◽  
Muscle Area ◽  
Muscle Properties ◽  
Functional Studies ◽  
Biomechanical Models ◽  
Assessment Techniques ◽  
Masticatory System ◽  
Future Work

Measures of attachment or accommodation area on the skeleton are a popular means of rapidly generating estimates of muscle proportions and functional performance for use in large-scale macroevolutionary studies. Herein, we provide the first evaluation of the accuracy of these muscle area assessment (MAA) techniques for estimating muscle proportions, force outputs and bone loading in a comparative macroevolutionary context using the rodent masticatory system as a case study. We find that MAA approaches perform poorly, yielding large absolute errors in muscle properties, bite force and particularly bone stress. Perhaps more fundamentally, these methods regularly fail to correctly capture many qualitative differences between rodent morphotypes, particularly in stress patterns in finite-element models. Our findings cast doubts on the validity of these approaches as means to provide input data for biomechanical models applied to understand functional transitions in the fossil record, and perhaps even in taxon-rich statistical models that examine broad-scale macroevolutionary patterns. We suggest that future work should go back to the bones to test if correlations between attachment area and muscle size within homologous muscles across a large number of species yield strong predictive relationships that could be used to deliver more accurate predictions for macroevolutionary and functional studies.

scholarly journals Evolutionary biomechanics: hard tissues and soft evidence?

2021 ◽  
Vol 288 (1945) ◽  
pp. 20202809
Author(s):  
Sarah Broyde ◽  
Matthew Dempsey ◽  
Linjie Wang ◽  
Philip G. Cox ◽  
Michael Fagan ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Functional Performance ◽  
Reconstruction Error ◽  
Muscle Properties ◽  
Tissue Properties ◽  
Biomechanical Models ◽  
Reconstruction Methods ◽  
Quantitative Accuracy ◽  
Masticatory System ◽  
Relative Differences

Biomechanical modelling is a powerful tool for quantifying the evolution of functional performance in extinct animals to understand key anatomical innovations and selective pressures driving major evolutionary radiations. However, the fossil record is composed predominantly of hard parts, forcing palaeontologists to reconstruct soft tissue properties in such models. Rarely are these reconstruction approaches validated on extant animals, despite soft tissue properties being highly determinant of functional performance. The extent to which soft tissue reconstructions and biomechanical models accurately predict quantitative or even qualitative patterns in macroevolutionary studies is therefore unknown. Here, we modelled the masticatory system in extant rodents to objectively test the ability of current muscle reconstruction methods to correctly identify quantitative and qualitative differences between macroevolutionary morphotypes. Baseline models generated using measured soft tissue properties yielded differences in muscle proportions, bite force, and bone stress expected between extant sciuromorph, myomorph, and hystricomorph rodents. However, predictions from models generated using reconstruction methods typically used in fossil studies varied widely from high levels of quantitative accuracy to a failure to correctly capture even relative differences between macroevolutionary morphotypes. Our novel experiment emphasizes that correctly reconstructing even qualitative differences between taxa in a macroevolutionary radiation is challenging using current methods. Future studies of fossil taxa should incorporate systematic assessments of reconstruction error into their hypothesis testing and, moreover, seek to expand primary datasets on muscle properties in extant taxa to better inform soft tissue reconstructions in macroevolutionary studies.

Flexibility Effects in a Single Link Robotic Manipulator

1993 ◽  
Author(s):  
C. Nataraj
Keyword(s):  
Large Scale ◽  
Robotic Manipulator ◽  
Flexible Beam ◽  
Rotating Speed ◽  
Weighted Residuals ◽  
Individual Interaction ◽  
Single Link ◽  
Rigid Mass ◽  
The Individual ◽  
Future Work

Abstract A single link robotic manipulator is modeled as a rotating flexible beam with a rigid mass at the tip and accurate energy expressions are derived. The resulting partial differential equations are solved using an approximate method of weighted residuals. From the solutions, coupling between axial and flexural deformations and the interactions with rigid body motions are rigorously analyzed. The emphasis in the current paper is not on an exhaustive analysis of existing systems but it is rather intended to compare and highlight the various flexibility effects in a relatively simple system. Hence, a nondimensional parametric analysis is performed to determine the effect of several parameters (including the rotating speed) on the errors and the individual interaction effects are discussed. Comparison with previous work in the field shows important phenomena often ignored or buried in large scale numerical analyses. Future work including application to multi-link robots is outlined.

Structure Preserving Non-Photorealistic Rendering Framework for Image Abstraction and Stylization of Low-Illuminated and Underexposed Images

2021 ◽  
Vol 11 (2) ◽  
pp. 22-45
Author(s):  
Pavan Kumar ◽  
Poornima B. ◽  
Nagendraswamy H. S. ◽  
Manjunath C.
Keyword(s):  
Structural Features ◽  
Image Features ◽  
Visual Features ◽  
Structure Preserving ◽  
Photorealistic Rendering ◽  
Assessment Techniques ◽  
Contemporary Work ◽  
Image Abstraction ◽  
Future Work ◽  
Background Content

The proposed abstraction framework manipulates the visual-features from low-illuminated and underexposed images while retaining the prominent structural, medium scale details, tonal information, and suppresses the superfluous details like noise, complexity, and irregular gradient. The significant image features are refined at every stage of the work by comprehensively integrating a series of AnshuTMO and NPR filters through rigorous experiments. The work effectively preserves the structural features in the foreground of an image and diminishes the background content of an image. Effectiveness of the work has been validated by conducting experiments on the standard datasets such as Mould, Wang, and many other interesting datasets and the obtained results are compared with similar contemporary work cited in the literature. In addition, user visual feedback and the quality assessment techniques were used to evaluate the work. Image abstraction and stylization applications, constraints, challenges, and future work in the fields of NPR domain are also envisaged in this paper.

Research and industrialisation of Hermetia illucens L. in China

2020 ◽  
Vol 6 (1) ◽  
pp. 5-12
Author(s):  
J.B. Zhang ◽  
J.K. Tomberlin ◽  
M.M. Cai ◽  
X.P. Xiao ◽  
L.Y. Zheng ◽  
...  
Keyword(s):  
Large Scale ◽  
Organic Waste ◽  
Animal Feed ◽  
Egg Laying ◽  
Breeding Method ◽  
Hermetia Illucens ◽  
Cold Temperatures ◽  
The Usa ◽  
The Government ◽  
Future Work

The larvae of the black soldier fly (BSF), Hermetia illucens L., are commonly associated with decaying organic wastes. Over the past 15 years, investigators in China have conducted extensive research exploring the use of BSF larvae to recycle organic materials as a means to protect the environment, while producing products of value, such as protein and bioenergy. Initial efforts were based on a BSF strain from the USA. However, since then, H. illucens strains from specimens collected in Hubei and Guangdong Provinces have been established and used as models to explore the use of this species in sustainable agriculture. China has played an instrumental role in developing an in-door breeding method using a quartz-iodine lamp rather than depend on natural sunlight. This discovery has allowed the establishment of in-door BSF colonies in regions throughout the world where abiotic conditions (i.e. cold temperatures) are preventative. Researchers in China paved the way for using microbes as a means to enhance BSF production including, enhancing BSF egg-laying as well as waste reduction. Furthermore, bacteria from BSF gut or waste can be cultured and used to promote BSF growth, shorten conversion time, and enhanced conversion efficacy. Recent efforts have demonstrated BSF larvae can degrade antibiotics as well as suppress noxious odours in livestock manure. Due to the efforts of research on BSF in China, numerous companies that recycle organic waste at a large scale (>20 tonnes waste digested/day), have been established. Resulting products include insect powder, and live BSFL that can be used as animal feed ingredients for livestock (e.g. eels and frogs), while protecting the environment. Future work will decipher the mechanisms regulating BSF larval conversion of organic waste so that the system can be optimised. However, efforts are still needed at the government level to establish quality assurance standards if this process is truly to become established as an industry in China.

An Applicative Survey on Few-Shot Learning

2021 ◽  
Vol 15 ◽  
Author(s):  
Jianwei Zhang ◽  
Xubin Zhang ◽  
Lei Lv ◽  
Yining Di ◽  
Wei Chen
Keyword(s):  
Large Scale ◽  
Representation Learning ◽  
Language Models ◽  
Data Sets ◽  
Research Directions ◽  
Large Scale Data ◽  
Cross Domain ◽  
Meta Learning ◽  
Definition Of ◽  
Future Work

Background: Learning discriminative representation from large-scale data sets has made a breakthrough in decades. However, it is still a thorny problem to generate representative embedding from limited examples, for example, a class containing only one image. Recently, deep learning-based Few-Shot Learning (FSL) has been proposed. It tackles this problem by leveraging prior knowledge in various ways. Objective: In this work, we review recent advances of FSL from the perspective of high-dimensional representation learning. The results of the analysis can provide insights and directions for future work. Methods: We first present the definition of general FSL. Then we propose a general framework for the FSL problem and give the taxonomy under the framework. We survey two FSL directions: learning policy and meta-learning. Results: We review the advanced applications of FSL, including image classification, object detection, image segmentation and other tasks etc., as well as the corresponding benchmarks to provide an overview of recent progress. Conclusion: FSL needs to be further studied in medical images, language models, and reinforcement learning in future work. In addition, cross-domain FSL, successive FSL, and associated FSL are more challenging and valuable research directions.

scholarly journals In-Fiber Structured Particles and Filament Arrays from the Perspective of Fluid Instabilities

2020 ◽  
Vol 2 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Bingrui Xu ◽  
Shuqi Ma ◽  
Yuanzhuo Xiang ◽  
Jing Zhang ◽  
Meifang Zhu ◽  
...  
Keyword(s):  
Thermal Treatment ◽  
Large Scale ◽  
The Other ◽  
Materials Selection ◽  
Capillary Instability ◽  
Fluid Instabilities ◽  
Fiber Devices ◽  
Filamentation Instability ◽  
Future Work ◽  
Thermal Drawing

AbstractIn-fiber structured particles and filament array have been recently emerging, providing unique advantages of feasible fabrication, diverse structures and sophisticated functionalities. This review will focus on the progress of this topic mainly from the perspective of fluid instabilities. By suppressing the capillary instability, the uniform layered structures down to nanometers are attained with the suitable materials selection. On the other hand, by utilizing capillary instability via post-drawing thermal treatment, the unprecedent structured particles can be designed with multimaterials for multifunctional fiber devices. Moreover, an interesting filamentation instability of a stretching viscous sheet has been identified during thermal drawing, resulting in an array of filaments. This review may inspire more future work to produce versatile devices for fiber electronics, either at a single fiber level or in large-scale fabrics and textiles, simply by manipulating and controlling fluid instabilities.

Further Evaporation and Final Treatment of Process-Water Concentrates

1999 ◽  
Vol 40 (11-12) ◽  
pp. 25-32
Author(s):  
Paterson McKeough ◽  
Leena Fagernäs
Keyword(s):  
Large Scale ◽  
Treatment Process ◽  
Treatment Options ◽  
Paper Mill ◽  
Pilot Scale ◽  
Forced Circulation ◽  
Final Treatment ◽  
Solids Content ◽  
Combustion Processes ◽  
Future Work

The study is part of a longer-term effort aimed at developing a separate treatment process for evaporation-concentrates of paper-mill process waters. This article deals with research on the two key processing steps; namely, the further evaporation and the final treatment of the concentrates. In laboratory experiments, various feed waters, including several different TMP filtrates, were evaporated to high dry-solids contents. The condensates recovered in most experiments contained relatively small amounts of organic matter. The extent of vapourisation of organic acids, relative to water, increased somewhat with increase in dry-solids content. Two TMP concentrates from large-scale evaporation plants were further concentrated in a pilot-scale forced-circulation evaporator. Viscosity was the factor limiting the extent of concentration. Using an evaporation temperature of about 80°C, the maximum dry-solids contents achieved with the two different concentrates were about 45 wt% and about 60 wt%, respectively. Fouling of heat-transfer surfaces was observed with both concentrates. A techno-economic evaluation of final-treatment options for alkali-rich concentrates is under way. According to intermediate results, molten-phase combustion processes would not require support fuel once the dry-solids content of TMP concentrate exceeds about 50 wt%. The aim of future work is to optimise the overall treatment process.

scholarly journals OLDER ADULTS’ OPINIONS ON DIFFERENT VEHICLE TECHNOLOGIES

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S342-S343
Author(s):  
Sara A Freed ◽  
Lesley A Ross ◽  
Despina Stavrinos
Keyword(s):  
Older Adults ◽  
Functional Performance ◽  
Importance Rating ◽  
Collision Warning ◽  
Crash Avoidance ◽  
Importance Ratings ◽  
Vehicle Technology ◽  
Vehicle Technologies ◽  
Future Work ◽  
Collision Warning Systems

Abstract Vehicle technologies have the potential to greatly improve road safety. Given normative changes in cognitive, sensory and physical functioning, older drivers may particularly benefit from such technologies. However, little research has examined older adults’ opinions of vehicle technologies, descriptive differences of individuals more likely to have positive opinions of vehicle technologies, and how their opinions may differ depending on the type of vehicle technology. The current study examined older adults’ opinions on vehicle technology in a sample of 72 adults between 65 and 85 years (M = 72.3, SD = 5.36, 48% women). Participants were asked, “How important is [parking assistance, crash avoidance systems, early collision warnings, built-in GPS] in choosing a new vehicle?” on a scale from 1 (“not at all”) to 5 (“must have”). On average, participants rated built-in GPS as the most important (M = 3.81, SD=1.10) with parking assist as the least important (M=1.86, SD=1.13). We used correlational analyses to examine the association between demographic and personality and importance ratings. Women were more likely to rate greater importance for built-in GPS than men (r=.35, p<.05). Age, education, self-reported driving quality, and self-reported average weekly driving miles were not significantly associated with importance rating. In terms of personality, only higher levels of extraversion were associated with more positive ratings of early collision warning systems (r=.24, p<.05). Vehicle technology design and education should take older adults’ preferences into account and consider individual differences, and future work should examine other predictors of vehicle technology preferences such as functional performance.

scholarly journals In situ predator conditioning of naive prey prior to reintroduction

2019 ◽  
Vol 374 (1781) ◽  
pp. 20180058 ◽  
Author(s):  
Daniel T. Blumstein ◽  
Mike Letnic ◽  
Katherine E. Moseby
Keyword(s):  
Small Groups ◽  
Large Scale ◽  
Management Tool ◽  
Behavioural Ecology ◽  
Ecological Community ◽  
Theme Issue ◽  
Selection For ◽  
Future Work ◽  
Dynamics Of Populations

Many translocations and introductions to recover threatened populations fail because predators kill prey soon after release; a problem exacerbated for predator-naive prey. While pre-release training has been shown to work in some situations, it is time consuming and relies on using inferred predator cues and treating small groups. We review a relatively new and very promising management tool: in situ , pre-release predator conditioning. Here, the goal is to allow prey in large enclosures to live with low densities of predators to accelerate selection for antipredator traits (in an evolutionary sense) or provide prey essential experience with predators that they will later encounter. We review the published results of a large-scale, controlled experiment where we have permitted burrowing bettongs ( Bettongia lesueur ) and greater bilblies ( Macrotis lagotis ) to live with low densities of feral cats ( Felis catus ), a species implicated in their widespread decline and localized extinction. We found that both species could persist with cats, suggesting that future work should define coexistence thresholds—which will require knowledge of prey behaviour as well as the structure of the ecological community. Compared to control populations, predator-naive prey exposed to cats has a suite of morphological and behavioural responses that seemingly have increased their antipredator abilities. Results suggest that predator-conditioned bilbies survive better when released into a large enclosure with an established cat population; future work will determine whether this increased survival extends to the wild. This article is part of the theme issue ‘Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation’.

Community Structure in Service-Oriented Enterprises Collaboration Network

2011 ◽  
Vol 314-316 ◽  
pp. 2033-2036
Author(s):  
Fu Qiang Zhang ◽  
Ping Yu Jiang
Keyword(s):  
Community Structure ◽  
Large Scale ◽  
Collaboration Network ◽  
Service Oriented ◽  
Future Work ◽  
Clustering Behavior

Service-oriented manufacturing is a new manufacturing paradigm, which has appeared in large-scale enterprises cluster in recent years. In this paper, the property of community structure for service-oriented enterprises collaboration network (so-ECN) has been investigated. First, characteristics and modeling of so-ECN are presented. Then, implementing procedure of community structure is provided to evaluate the collaboration clustering behavior. Finally, the conclusions and future work are put forward.

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