scholarly journals Field Testing of Biohybrid Robotic Jellyfish to Demonstrate Enhanced Swimming Speeds

Biomimetics ◽  
2020 ◽  
Vol 5 (4) ◽  
pp. 64
Author(s):  
Nicole W. Xu ◽  
James P. Townsend ◽  
John H. Costello ◽  
Sean P. Colin ◽  
Brad J. Gemmell ◽  
...  
Keyword(s):  
Coastal Waters ◽  
Environmental Changes ◽  
Damage Tolerance ◽  
Field Testing ◽  
Time Dependent ◽  
Robotic Manipulation ◽  
Large Animal ◽  
Ocean Monitoring ◽  
Future Work ◽  
Natural Dynamic

Biohybrid robotic designs incorporating live animals and self-contained microelectronic systems can leverage the animals’ own metabolism to reduce power constraints and act as natural chassis and actuators with damage tolerance. Previous work established that biohybrid robotic jellyfish can exhibit enhanced speeds up to 2.8 times their baseline behavior in laboratory environments. However, it remains unknown if the results could be applied in natural, dynamic ocean environments and what factors can contribute to large animal variability. Deploying this system in the coastal waters of Massachusetts, we validate and extend prior laboratory work by demonstrating increases in jellyfish swimming speeds up to 2.3 times greater than their baseline, with absolute swimming speeds up to 6.6 ± 0.3 cm s−1. These experimental swimming speeds are predicted using a hydrodynamic model with morphological and time-dependent input parameters obtained from field experiment videos. The theoretical model can provide a basis to choose specific jellyfish with desirable traits to maximize enhancements from robotic manipulation. With future work to increase maneuverability and incorporate sensors, biohybrid robotic jellyfish can potentially be used to track environmental changes in applications for ocean monitoring.

scholarly journals Field testing of biohybrid robotic jellyfish to demonstrate enhanced swimming speeds

2020 ◽  
Author(s):  
Nicole W. Xu ◽  
James P. Townsend ◽  
John H. Costello ◽  
Sean P. Colin ◽  
Bradford J. Gemmell ◽  
...  
Keyword(s):  
Coastal Waters ◽  
Environmental Changes ◽  
Damage Tolerance ◽  
Field Testing ◽  
Time Dependent ◽  
Robotic Manipulation ◽  
Large Animal ◽  
Ocean Monitoring ◽  
Future Work ◽  
Natural Dynamic

ABSTRACTBiohybrid robotic designs incorporating live animals and self-contained microelectronic systems can leverage the animals’ own metabolism to reduce power constraints and act as natural chassis and actuators with damage tolerance. Previous work established that biohybrid robotic jellyfish can exhibit enhanced speeds up to 2.8 times their baseline behavior in laboratory environments. However, it remains unknown if the results could be applied in natural, dynamic ocean environments and what factors can contribute to large animal variability. Deploying this system in the coastal waters of Massachusetts, we validate and extend prior laboratory work by demonstrating increases in jellyfish swimming speeds up to 2.3 times greater than their baseline, with absolute swimming speeds up to 6.6 ± 0.3 cm s-1. These experimental swimming speeds are predicted using a hydrodynamic model with morphological and time-dependent input parameters obtained from field experiment videos. The theoretical model can provide a basis to choose specific jellyfish with desirable traits to maximize enhancements from robotic manipulation. With future work to increase maneuverability and incorporate sensors, biohybrid robotic jellyfish can potentially be used track environmental changes in applications for ocean monitoring.

New strength metrics for containerboards: influences of basic papermaking factors

2018 ◽  
Vol 33 (4) ◽  
pp. 592-602
Author(s):  
Amanda Mattsson ◽  
Tetsu Uesaka
Keyword(s):  
Time Dependent ◽  
New Method ◽  
Creep Tests ◽  
Material Parameters ◽  
Dependent Failures ◽  
Short Term Strength ◽  
New Material ◽  
End Use ◽  
Future Work ◽  
Operating Window

Abstract In end-use, containerboard is subjected to a variety of loading histories, such as seconds of loading/unloading, hours of vibration, days of creep load. The fundamental question is whether the commonly measured static strength represents “strength” under these conditions. Another question is, since those time-dependent failures are notoriously variable, how to describe the probabilistic aspect. This study concerns the characterisation of these different facets of “strength”. In our earlier work, we have investigated the theoretical framework for time-dependent, probabilistic failures, and identified three material parameters: (1) characteristic strength, {S_{c}}, representing short-term strength, (2) brittleness/durability parameter, ρ, and (3) reliability parameter, β. We have also developed a new method that allows us to determine all these parameters much faster than typical creep tests. Using the new method, we have started investigating effects of basic papermaking variables on the new material parameters. Among the samples tested, the parameter ρ varied from 20 to 50, and β from 0.5 to 1.0. This suggests that, even within the current papermaking practice, there is a wide operating window to tune these new material parameters. The future work is, therefore, to find specific manufacturing variables that can systematically change these new material parameters.

scholarly journals Resilience of Atlantic Slippersnail Crepidula fornicata Larvae in the Face of Severe Coastal Acidification

2018 ◽  
Author(s):  
Nicola G. Kriefall ◽  
Jan A. Pechenik ◽  
Anthony Pires ◽  
Sarah W. Davies
Keyword(s):  
Gene Expression ◽  
Environmental Changes ◽  
Larval Mortality ◽  
Shell Growth ◽  
Crepidula Fornicata ◽  
Physiological Limits ◽  
Nearshore Ecosystems ◽  
The Face ◽  
Intertidal Gastropod ◽  
Future Work

AbstractGlobally, average oceanic pH is dropping, and it will continue to decline into the foreseeable future. This ocean acidification (OA) will exacerbate the natural fluctuations in pH that nearshore ecosystems currently experience daily, potentially pushing marine organisms to their physiological limits. Adults of Crepidula fornicata (the Atlantic slippersnail) have proven remarkably resilient to many environmental changes, which is perhaps not surprising considering that they are common intertidally, have a geographically large native range, and have been extremely successful at invading coastal water in many other parts of the world. However, the larvae of C. fornicata have been shown to be somewhat more vulnerable than adults to the effects of reduced pH. Research to date has focused on the physiological impacts of OA on C. fornicata larvae; few studies have explored shifts in gene expression resulting from changes in pH. In the present study, we examined the response of young (4- day old) C. fornicata larvae to two extreme OA treatments (pH 7.5 and 7.6) relative to pH 8.0, documenting both phenotypic and genome-wide gene expression responses. We found that rearing larvae at reduced pH had subtle influences on gene expression, predominantly involving downregulation of genes related to growth and metabolism, accompanied by significantly reduced shell growth rates only for larvae reared at pH 7.5. Additionally, 10-day old larvae that had been reared at the two lower pH levels were far less likely to metamorphose within six hours when exposed to inducer. However, all larvae eventually reached similarly high levels of metamorphosis 24 hours after settlement induction. Finally, there were no observed impacts of OA on larval mortality. Taken together, our results indicate that far future OA levels have observable, but not severe, impacts on C. fornicata larvae, which is consistent with the resilience of this invasive snail across rapidly changing nearshore ecosystems. We propose that future work should delve further into the physiological and transcriptomic responses of all life history stages to gain a more comprehensive understanding of how OA impacts the intertidal gastropod C. fornicata.

scholarly journals Dynamic metabolic modelling of overproduced protein secretion in Streptomyces lividans using adaptive DFBA

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Jósé R. Valverde ◽  
Sonia Gullón ◽  
Clara A. García-Herrero ◽  
Iván Campoy ◽  
Rafael P. Mellado
Keyword(s):  
Protein Secretion ◽  
Environmental Changes ◽  
Streptomyces Lividans ◽  
Secretory Protein ◽  
Time Dependent ◽  
Secretory Proteins ◽  
Exogenous Dna ◽  
Dynamic Flux Balance Analysis ◽  
Balance Analysis ◽  
Living Organisms

Abstract Background Streptomyces lividans is an appealing host for the production of proteins of biotechnological interest due to its relaxed exogenous DNA restriction system and its ability to secrete proteins directly to the medium through the major Sec or the minor Tat routes. Often, protein secretion displays non-uniform time-dependent patterns. Understanding the associated metabolic changes is a crucial step to engineer protein production. Dynamic Flux Balance Analysis (DFBA) allows the study of the interactions between a modelled organism and its environment over time. Existing methods allow the specification of initial model and environment conditions, but do not allow introducing arbitrary modifications in the course of the simulation. Living organisms, however, display unexpected adaptive metabolic behaviours in response to unpredictable changes in their environment. Engineering the secretion of products of biotechnological interest has systematically proven especially difficult to model using DFBA. Accurate time-dependent modelling of complex and/or arbitrary, adaptive metabolic processes demands an extended approach to DFBA. Results In this work, we introduce Adaptive DFBA, a novel, versatile simulation approach that permits inclusion of changes in the organism or the environment at any time in the simulation, either arbitrary or interactively responsive to environmental changes. This approach extends traditional DFBA to allow steering arbitrarily complex simulations of metabolic dynamics. When applied to Sec- or Tat-dependent secretion of overproduced proteins in S. lividans, Adaptive DFBA can overcome the limitations of traditional DFBA to reproduce experimental data on plasmid-free, plasmid bearing and secretory protein overproducing S. lividans TK24, and can yield useful insights on the behaviour of systems with limited experimental knowledge such as agarase or amylase overproduction in S. lividans TK21. Conclusions Adaptive DFBA has allowed us to overcome DFBA limitations and to generate more accurate models of the metabolism during the overproduction of secretory proteins in S. lividans, improving our understanding of the underlying processes. Adaptive DFBA is versatile enough to permit dynamical metabolic simulations of arbitrarily complex biotechnological processes.

scholarly journals Production of Biodiesel from Marine Macroalgae occurring in the Gulf of Guinea, off the Coast of Ghana

2019 ◽  
Vol 60 (1) ◽  
pp. 50-58
Author(s):  
G. K. Ameka ◽  
L. K. Doamekpor ◽  
A. A. Amadu ◽  
A. P. Amamoo
Keyword(s):  
Lipid Content ◽  
Coastal Waters ◽  
Commercial Production ◽  
Marine Macroalgae ◽  
Liquid Fuels ◽  
Gulf Of Guinea ◽  
Caulerpa Taxifolia ◽  
Algae Biomass ◽  
Chaetomorpha Linum ◽  
Future Work

The purpose of this study was to determine the suitability of marine macroalgae (also known as seaweeds), from the Gulf of Guinea, off the coast of Ghana, for the production of biodiesel as an alternative to liquid fuels like gasoil and gasoline. Five green marine macroalgae species: Caulerpa taxifolia, Chaetomorpha antennina, Chaetomorpha linum, Ulva fasciata, and Ulva flexuosa, were collected from the coastal waters of Ghana at West Tema Rocks during low tide. Algal lipids were extracted from dried algae biomass with hexane and diethyl ether. Biodiesel was produced from algal lipids by base-catalysed transesterification, with alcohol. The lipid content of samples was highest in C. linum (1.13 g; 5.65% dry wt.) and lowest in C. antennina (0.54 g; 2.70% dry wt.). Similarly, the quantity of biodiesel produced from the lipids was highest in C. linum (0.97 g; 4.85% dry wt.) and lowest in C. antennina (0.48 g; 2.40% dry wt.). The quantity of biodiesel produced from samples of the five species fell well within the range obtained for such species worldwide. The implications of the yield of biodiesel for commercial production and future work on marine macroalgae from Ghana as source of biofuel are discussed.

scholarly journals Variation of phytoplankton community structure in Quang Ngai coastal waters during 2015–2019

2021 ◽  
Vol 20 (4A) ◽  
pp. 21-33
Author(s):  
Huynh Thi Ngoc Duyen ◽  
Tran Thi Minh Hue ◽  
Tran Thi Le Van ◽  
Phan Tan Luom ◽  
Nguyen Ngoc Lam ◽  
...  
Keyword(s):  
Community Structure ◽  
Environmental Impacts ◽  
Coastal Waters ◽  
Phytoplankton Community ◽  
Environmental Changes ◽  
Diversity Indices ◽  
Species Number ◽  
Phytoplankton Community Structure ◽  
Phytoplankton Diversity ◽  
Phytoplankton Communities

Phytoplankton in coastal waters are important for the evaluation of either biodiversity or environmental impacts because of this highly vulnerable ecosystem. Seasonal and annual changes in the phytoplankton community structure in Quang Ngai waters during the period 2015 to 2019 were analyzed to assess the phytoplankton diversity and reveal possible causes of these changes. A total of 366 phytoplankton taxa belonging to 10 classes were identified throughout this present study. The highest species number was found in 2019 with 295 taxa, followed by those in 2015 (247), 2017 (185), and 2018 (99). The waters of Ly Son transect showed the highest diversity and most stable phytoplankton communities in both dry and rainy seasons, whereas the stations of Quang Ngai coast revealed high variability of the communities. All diversity indices including Margalef, Pielou, Shannon, Simpson did not reflect well differences in average values but a certain degree of variances, indicating possible environmental impacts. During the study time, there were blooms of certain diatom species including Skeletonema spp. in 2015 and Pseudo-nitzschia spp. in 2019. Analysis of a diatoms index, Centric/Pennate ratio, indicated that the waters were in eutrophic status with a decreasing trend from the coast area to Ly Son island in 2015 and 2019. This research built up fundamental data on phytoplankton communities for Quang Ngai province. The Centric/Pennate diatom index and diversity would be used as indicators for environmental changes and their values provided warning of eutrophication in this coastal waters including the water surrounding Ly Son island.

scholarly journals Comparing the Durability and Strength of Simple Adhesive Recipes and PVA-Based Glues

2021 ◽  
Vol 10 (2) ◽  
Author(s):  
Bethany Elliott ◽  
Sara Fox
Keyword(s):  
Tensile Strength ◽  
Environmental Changes ◽  
Gum Arabic ◽  
Cohesive Strength ◽  
Large Structures ◽  
Factory Production ◽  
Essential Components ◽  
Cost Efficient ◽  
The Stability ◽  
Future Work

Adhesives are essential components of factory production, for maintaining the stability of large structures, and even for pastimes such as paper-mâché crafts. Therefore, it is imperative that adhesives retain their durability and strength when under pressure. The purpose of this project was to test the tensile strength of several adhesive recipes in order to ultimately create a stronger adhesive. To test the tensile strength of each adhesive, one of the adherends had weights attached and was suspended and the amount of time that the adhesive stayed attached was recorded. After completing the experimental procedures, it was found that the flour/water adhesive, cornstarch adhesive, and the waterproof adhesives performed the best, Elmer’s glue and the Gum Arabic adhesive performed less well than the first three adhesives, and Elmer’s glue with beads did not stay attached. In conclusion, the simple adhesives recipes outperformed Elmer’s glue, most likely because they had better cohesive strength and were able to dry faster. The results of this experiment can aid in the creation of a stronger and more cost-efficient adhesive product. Based on these results, future work will be aimed towards determining the effects of environmental changes like humidity and temperature on the tensile strength.

scholarly journals Anemia and Incident End-Stage Kidney Disease

Kidney360 ◽  
2020 ◽  
Vol 1 (7) ◽  
pp. 623-630
Author(s):  
Santosh L. Saraf ◽  
Jesse Y. Hsu ◽  
Ana C. Ricardo ◽  
Rupal Mehta ◽  
Jing Chen ◽  
...  
Keyword(s):  
Time Dependent ◽  
World Health ◽  
Ckd Progression ◽  
Increased Risk ◽  
Multivariable Analyses ◽  
Using Data ◽  
Health Organization ◽  
End Stage ◽  
Future Work ◽  
Racial Ethnic

BackgroundCKD progression can be a cause and potentially a consequence of anemia. Previous studies suggesting that anemia is associated with CKD progression have not used methodologic approaches to address time-dependent confounding.MethodsWe evaluated the association of anemia (defined using World Health Organization criteria of hemoglobin <12 g/dl in women and <13 g/dl in men) with incident ESKD and all-cause death in individuals with CKD using data from the Chronic Renal Insufficiency Cohort Study. Marginal structural models were used to account for time-dependent confounding.ResultsAmong 3919 participants, 1859 (47%) had anemia at baseline. Over median follow-up of 7.8 years, we observed 1010 ESKD events and 994 deaths. In multivariable analyses, individuals with anemia had higher risk for ESKD compared with those without (HR, 1.62; 95% CI, 1.24 to 2.11). In stratified analyses, the increased risk for incident ESKD with anemia was observed in males (HR, 2.15; 95% CI, 1.53 to 3.02) but not females (HR, 1.20; 95% CI, 0.82 to 1.78). The association between anemia and ESKD was significant among all racial/ethnic groups except non-Hispanic blacks (non-Hispanic white, HR, 2.16; 95% CI, 1.53 to 3.06; Hispanic, HR, 1.92; 95% CI, 1.04 to 3.51; others, HR, 2.94; 95% CI, 1.16 to 7.44; non-Hispanic black, HR, 1.39; 95% CI, 0.95 to 2.02). There was no association between anemia and all-cause death.ConclusionsIn this cohort, anemia was independently associated with increased risk for incident ESKD. Future work is needed to evaluate the mechanisms by which anemia leads to CKD progression as well as the effect of novel therapeutic agents to treat anemia.

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