Mussel Byssal Attachment Weakened by Anthropogenic Noise

The increasing underwater noise generated by anthropogenic activities has been widely recognized as a significant and pervasive pollution in the marine environment. Marine mussels are a family of sessile bivalves that attach to solid surfaces via the byssal threads. They are widely distributed along worldwide coastal areas and are of great ecological and socio-economic importance. Studies found that anthropogenic noise negatively affected many biological processes and/or functions of marine organisms. However, to date, the potential impacts of anthropogenic noise on mussel byssal attachment remain unknown. Here, the thick shell mussels Mytilus coruscus were exposed to an ambient underwater condition (∼50 dB re 1 μPa) or the playbacks of pile-driving noise (∼70 or ∼100 dB re 1 μPa) for 10 days. Results showed that the noise significantly reduced the secretion of byssal threads (e.g., diameter and volume) and weakened their mechanical performances (e.g., strength, extensibility, breaking stress, toughness and failure location), leading to a 16.95–44.50% decrease in mussel byssal attachment strength. The noise also significantly down-regulated the genes expressions of seven structural proteins (e.g., mfp-1, mfp-2, mfp-3, mfp-6, preCOL-P, preCOL-NG, and preCOL-D) of byssal threads, probably mediating the weakened byssal attachment. Given the essential functions of strong byssal attachment, the findings demonstrate that the increasing underwater anthropogenic noise are posing a great threat to mussel population, mussel-bed community and mussel aquaculture industry. We thus suggest that future work is required to deepen our understanding of the impacts of anthropogenic noise on marine invertebrates, especially these with limited locomotion ability, like bivalves.

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Impacts of pH on the Fitness and Immune System of Pacific White Shrimp

Frontiers in Marine Science ◽

10.3389/fmars.2021.748837 ◽

2021 ◽

Vol 8 ◽

Author(s):

Veran Weerathunga ◽

Wei-Jen Huang ◽

Sam Dupont ◽

Hsueh-Han Hsieh ◽

Nathangi Piyawardhana ◽

...

Keyword(s):

Immune System ◽

Industrial Revolution ◽

Marine Invertebrates ◽

Anthropogenic Activities ◽

Low Ph ◽

Pacific White Shrimp ◽

White Shrimp ◽

Surface Ocean ◽

Total Hemocyte Count ◽

Fitness Parameters

The atmospheric partial pressure of CO2 (pCO2) has been increasing dramatically since the beginning of the industrial revolution and about 30% of the CO2 produced by anthropogenic activities was absorbed by the ocean. This led to a perturbation of the seawater carbonate chemistry resulting in a decrease of the average surface ocean pH by 0.1 and termed ocean acidification (OA). Projections suggest that pCO2 may reach 900 μatm by the end of the twenty-first century lowering the average pH of the surface ocean by 0.4 units. The negative impacts of OA on many species of marine invertebrates such as mollusks, echinoderms, and crustaceans are well documented. However, less attention has been paid to the impacts of low pH on fitness and immune system in crustaceans. Here, we exposed Pacific white shrimps to 3 different pHs (nominal pH 8.0, 7.9, and 7.6) over a 100-days experiment. We found that, even though there were no significant effects on fitness parameters (survival, growth and allometries between length and weight), some immune markers were modified under low pH. A significant decrease in total hemocyte count and phenoloxidase activity was observed in shrimps exposed to pH 7.6 as compared to pH 8.0; and phagocytosis rate significantly decreased with decreasing pH. A significant increase in superoxide production was also observed at pH 7.6 as compared to pH 8.0. All these results suggest that a 100-days exposure to pH 7.6 did not have a direct effect on fitness but lead to a modulation of the immune response.

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Void and Moisture Content of Fiber Reinforced Composites

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences ◽

10.37934/arfmts.87.3.7893 ◽

2021 ◽

Vol 87 (3) ◽

pp. 78-93

Author(s):

Nurul Zuhairah Mahmud Zuhudi ◽

Afiq Faizul Zulkifli ◽

Muzafar Zulkifli ◽

Ahmad Naim Ahmad Yahaya ◽

Nurhayati Mohd Nur ◽

...

Keyword(s):

Moisture Content ◽

Short Review ◽

Fiber Reinforced Composites ◽

Moisture Determination ◽

Reinforced Composites ◽

Fiber Reinforced ◽

Mechanical Performances ◽

Future Work ◽

Selection Of

In this paper, a short review on the void and moisture content studies of fiber reinforced composites for both, synthetic and natural based fibers are presented. The review summarized the research papers in which include experimental and theoretical works that related to the void and moisture content studies. In addition to that, this review paper highlighting a few research studies conducted in literature on the effects of the void and moisture on the mechanical performances of the composite. Few common measurement methods used for the void and moisture determination are discussed here. The aims of this short review, mainly to capture the trend ranging from the recent five years back and summarize the various studies and also to compare and conclude the most common method for the determination of the void and moisture content. This paper is mainly providing a baseline in the selection of the methods for the future work of the author’s work with regard to the reduction of the presence of voids and moisture occur during the impregnation process of fiber reinforced composites, especially when using natural-based fiber.

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A newly discovered radiation of endoparasitic gastropods and their coevolution with asteroid hosts in Antarctica

BMC Evolutionary Biology ◽

10.1186/s12862-019-1499-8 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 2

Author(s):

Kara K. S. Layton ◽

Greg W. Rouse ◽

Nerida G. Wilson

Keyword(s):

Marine Invertebrates ◽

Global Scale ◽

Morphological Data ◽

Sea Stars ◽

Single Host ◽

Scotia Arc ◽

Event Based ◽

Genus One ◽

Future Work ◽

The Antarctic

Abstract Background Marine invertebrates are abundant and diverse on the continental shelf in Antarctica, but little is known about their parasitic counterparts. Endoparasites are especially understudied because they often possess highly modified body plans that pose problems for their identification. Asterophila, a genus of endoparasitic gastropod in the family Eulimidae, forms cysts in the arms and central discs of asteroid sea stars. There are currently four known species in this genus, one of which has been described from the Antarctic Peninsula (A. perknasteri). This study employs molecular and morphological data to investigate the diversity of Asterophila in Antarctica and explore cophylogenetic patterns between host and parasite. Results A maximum-likelihood phylogeny of Asterophila and subsequent species-delimitation analysis uncovered nine well-supported putative species, eight of which are new to science. Most Asterophila species were found on a single host species, but four species were found on multiple hosts from one or two closely related genera, showing phylogenetic conservatism of host use. Both distance-based and event-based cophylogenetic analyses uncovered a strong signal of coevolution in this system, but most associations were explained by non-cospeciation events. Discussion The prevalence of duplication and host-switching events in Asterophila and its asteroid hosts suggests that synchronous evolution may be rare even in obligate endoparasitic systems. The apparent restricted distribution of Asterophila from around the Scotia Arc may be an artefact of concentrated sampling in the area and a low obvious prevalence of infection. Given the richness of parasites on a global scale, their role in promoting host diversification, and the threat of their loss through coextinction, future work should continue to investigate parasite diversity and coevolution in vulnerable ecosystems.

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MARINE INVERTEBRATES, INTENSE ANTHROPOGENIC NOISE, AND SQUID RESPONSE TO SEISMIC SURVEY PULSES

Bioacoustics ◽

10.1080/09524622.2008.9753861 ◽

2008 ◽

Vol 17 (1-3) ◽

pp. 315-318 ◽

Cited By ~ 3

Author(s):

R. D. McCAULEY ◽

J. FEWTRELL

Keyword(s):

Marine Invertebrates ◽

Seismic Survey ◽

Anthropogenic Noise

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Noise Footprint: A Proposal Within the Framework of FP7 AQUO Project to Define a Goal Based Approach Towards the Reduction of Underwater Radiated Noise From Shipping

Volume 7: Ocean Space Utilization; Professor Emeritus J. Randolph Paulling Honoring Symposium on Ocean Technology ◽

10.1115/omae2014-24424 ◽

2014 ◽

Cited By ~ 1

Author(s):

Eric Baudin ◽

Thomas Folegot ◽

Michel Andre ◽

Christian Audoly ◽

Enrico Rizzuto ◽

...

Keyword(s):

Work Group ◽

Noise Pollution ◽

Anthropogenic Noise ◽

Current Status ◽

Marine Biota ◽

Policy Makers ◽

Maritime Traffic ◽

Project Structure ◽

Applied Knowledge ◽

Future Work

The Marine Strategy Framework Directive has officially stated as soon as 2008 the anthropogenic noise due to shipping were to be mitigated. The policy makers, the yards and the ship owners still strongly rely on the expert studies and guidelines to find the appropriate methodology to assess and then mitigate the acoustic pollution impact shipping on the marine biota. To address this issue, the project AQUO “Achieve QUieter Oceans by shipping noise footprint reduction” (www.aquo.eu) started in October 2012 for 3 years. The AQUO project was built in the scope of FP7 European Research Framework. It involves 13 partners from 8 European countries, mixes academic experts, industry representatives from yard, classification society and other acoustic and bio-acoustic specialized bodies. Addressing the anthropogenic noise pollution into the marine biota is an increasing concern which is logically paired with the increasing commercial maritime traffic. The IMO itself has recently issued a first draft guideline, to be followed up during the next MEPC, addressing this matter. In parallel to the different achievements that are effective or in progress by standardization bodies or other delegated or assigned work group, the AQUO project aims to finally issue guidelines to be taken as methodological tools. The multi-disciplinary team of this project aims to comply with expectations from the different stakeholders. First, an overview of the project is given. The objectives and the related project structure are detailed so as to better understand which axes are chosen and studied. Secondly, it is here proposed to share the recent outcomes of AQUO project. The current status of applied knowledge, related legal decisions as well as standards empowerment are essential to identify the remaining needs and consequent expected efforts. Drawing first the background rationales the noise footprint concept is then detailed. The process followed towards the main objective of mitigating the anthropogenic noise from shipping will be partly revealed and completed by the expected future work to be achieved by 2015.

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Bacterial community dynamics during embryonic and larval development of three confamilial echinoids

10.1101/394478 ◽

2018 ◽

Author(s):

Tyler J. Carrier ◽

Adam M. Reitzel

Keyword(s):

Bacterial Community ◽

Larval Development ◽

Bacterial Communities ◽

Community Dynamics ◽

Marine Invertebrates ◽

Sea Urchins ◽

Larval Feeding ◽

Bacterial Community Dynamics ◽

Future Work ◽

Embryonic And Larval Development

ABSTRACTDevelopment of some animals is influenced by and, in some cases, dependent on the associated microbiota. The timing of when associated bacterial communities are established during the development of marine invertebrates and their subsequent dynamics across stages are known for only a few species. Here, we compare the bacterial communities of three confamilial echinoids from egg to juvenile using sequence-based approaches. Bacterial communities are established on unfertilized eggs and change gradually during embryonic and larval development. Despite the differences amongst these pre-metamorphic stages, approximately thirty-percent of OTUs identified in association with unfertilized egg were present in the juveniles. During embryonic development, host-associated communities diverged from the environmental microbiota but later converged following the onset of larval feeding. Taken together, the data presented here support the hypothesis that bacterial communities are established prior to fertilization and community composition shifts gradually thereafter, all while remaining distinct from the environment. Future work will need to determine the relative influence of the host and bacteria-bacteria interactions in shaping the associated bacterial community to determine the potential functional importance of bacteria during the development of larval sea urchins and benthic marine invertebrates more broadly.

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Unraveling the Detoxification Mechanism of 2,4-Dichlorophenol by Marine-Derived Mesophotic Symbiotic Fungi Isolated from Marine Invertebrates

Marine Drugs ◽

10.3390/md17100564 ◽

2019 ◽

Vol 17 (10) ◽

pp. 564 ◽

Cited By ~ 3

Author(s):

Efstratios Nikolaivits ◽

Andreas Agrafiotis ◽

Aikaterini Termentzi ◽

Kyriaki Machera ◽

Géraldine Le Goff ◽

...

Keyword(s):

Environmental Protection Agency ◽

Marine Invertebrates ◽

Anthropogenic Activities ◽

Environmental Pollutants ◽

Fungal Strains ◽

Adverse Health Effects ◽

Detoxification Mechanism ◽

The Us ◽

Symbiotic Fungi ◽

Living Organisms

Chlorophenols (CPs) are environmental pollutants that are produced through various anthropogenic activities and introduced in the environment. Living organisms, including humans, are exposed to these toxic xenobiotics and suffer from adverse health effects. More specifically, 2,4-dichlorophenol (2,4-DCP) is released in high amounts in the environment and has been listed as a priority pollutant by the US Environmental Protection Agency. Bioremediation has been proposed as a sustainable alternative to conventional remediation methods for the detoxification of phenolic compounds. In this work, we studied the potential of fungal strains isolated as symbionts of marine invertebrates from the underexplored mesophotic coral ecosystems. Hence, the unspecific metabolic pathways of these fungal strains are being explored in the present study, using the powerful analytical capabilities of a UHPLC-HRMS/MS. The newly identified 2,4-DCP metabolites add significantly to the knowledge of the transformation of such pollutants by fungi, since such reports are scarce.

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Intrapopulation variation in the behavioral responses of dwarf mongooses to anthropogenic noise

Behavioral Ecology ◽

10.1093/beheco/araa011 ◽

2020 ◽

Vol 31 (3) ◽

pp. 680-691 ◽

Cited By ~ 2

Author(s):

Emma Eastcott ◽

Julie M Kern ◽

Amy Morris-Drake ◽

Andrew N Radford

Keyword(s):

Traffic Noise ◽

Anthropogenic Noise ◽

Dominance Status ◽

Substantial Evidence ◽

Intrapopulation Variation ◽

Age Class ◽

Ambient Sound ◽

Global Pollutant ◽

Response Variation ◽

Future Work

Abstract Anthropogenic noise is an increasingly widespread pollutant, with a rapidly burgeoning literature demonstrating impacts on humans and other animals. However, most studies have simply considered if there is an effect of noise, examining the overall cohort response. Although substantial evidence exists for intraspecific variation in responses to other anthropogenic disturbances, this possibility has received relatively little experimental attention with respect to noise. Here, we used field-based playbacks with dwarf mongooses (Helogale parvula) to test how traffic noise affects vigilance behavior and to examine potential variation between individuals of different age class, sex, and dominance status. Foragers exhibited a stronger immediate reaction and increased their subsequent vigilance (both that on the ground and as a sentinel) in response to traffic-noise playback compared with ambient-sound playback. Traffic-noise playback also resulted in sentinels conducting longer bouts and being more likely to change post height or location than in ambient-sound playback. Moreover, there was evidence of variation in noise responses with respect to age class and dominance status but not sex. In traffic noise, foraging pups were more likely to flee and were slower to resume foraging than adults; they also tended to increase their vigilance more than adults. Dominants were more likely than subordinates to move post during sentinel bouts conducted in traffic-noise trials. Our findings suggest that the vigilance–foraging trade-off is affected by traffic noise but that individuals differ in how they respond. Future work should, therefore, consider intrapopulation response variation to understand fully the population-wide effects of this global pollutant.

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