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Background: The wild stocks of Pinctada maxima pearl oysters found off the coast of northern Australia are of critical importance for the sustainability of Australia's pearling industry. Locations inhabited by pearl oysters often have oil and gas reserves in the seafloor below and are therefore potentially subjected to seismic exploration surveys. The present study assessed the impact of a simulated commercial seismic survey on the transcriptome of pearl oysters. Animals were placed at seven distances (-1000, 0, 300, 500, 1000, 2000, and 6000 m) from the first of six operational seismic source sail lines. Vessel control groups were collected before the seismic survey started and exposed groups were collected after completion of six operational seismic sail lines (operated at varying distances over a four-day period). Samples from these groups were taken immediately and at 1, 3, and 6 months post-exposure. RNA-seq was used to identify candidate genes and pathways impacted by the seismic noise in pearl oyster mantle tissues. The quantified transcripts were compared using DESeq2 and pathway enrichment analysis was conducted using KEGG pathway, identifying differentially expressed genes and pathways associated with the seismic activity. Results: The study revealed the highest gene expression and pathway dysregulation after four days of exposure and a month post-exposure. However, this dysregulation diminished after three months, with only oysters at -1000 and 0 m displaying differential gene expression and pathway disruption six months post-exposure. Stress-induced responses were evident and impacted energy production, transcription, translation, and protein synthesis. Conclusion: Seismic activity impacted the gene expression and pathways of pearl oysters at distances up to 2000 m from the source after four days of exposure, and at distances up to 1000 m from the source one-month post-exposure. At three- and six-months post-exposure, gene and pathway dysregulations were mostly observed in oysters located closest to the seismic source at 0 and − 1000 m. Overall, our results suggest that oysters successfully activated stress responses to mitigate damage and maintain cellular homeostasis and growth in response to seismic noise exposure. [ABSTRACT FROM AUTHOR]

Simple Summary: As animals age, exposure to additional environmental stressors such as noise pollution might be more detrimental at the physiological and behavioural levels, but such an effect is not yet clear. In this study, we tested the effects of noise exposure for 24 h on young adults and old zebrafish. Based on different behavioural tests, we found that both noise and ageing caused anxiety responses when the animals were introduced to a novel environment as well as a tendency for social proximity. Such anxiety responses decreased when the animals were tested in groups. Since the old zebrafish already showed anxiety-like behaviour with a preference for bottom dwelling, noise treatment induced the opposite effect in these individuals, increasing their vertical exploration. This work is a first attempt to investigate the effects of noise and ageing on zebrafish, a reference model in hearing and ecotoxicology research. Overall, we suggest that old individuals may have distinct physiological and behavioural mechanisms for dealing with noisy environments. Noise pollution is creating a wide range of health problems related to physiological stress and anxiety that impact the social life of vertebrates, including humans. Ageing is known to be associated with changes in susceptibility to acoustic stimuli; however, the interaction between noise effects and senescence is not well understood. We tested the effects of 24 h continuous white noise (150 dB re 1 Pa) on both young adults and old zebrafish in terms of anxiety (novel tank diving test), social interactions (with mirror/conspecific attraction), and shoaling behaviour. Both noise and ageing induced higher anxiety responses in a novel environment. Since the old zebrafish showed longer bottom dwelling, acoustic treatment induced the opposite pattern with an initial increase in vertical exploration in the aged individuals. Both noise- and age-related anxiety responses were lowered when individuals were tested within a group. Regarding social interactions, both noise and ageing seemed to cause an increase in their proximity to a mirror. Although the results were not statistically significant, noise exposure seemed to further enhance conspecific attraction. Moreover, the interindividual distance within a shoal decreased with noise treatment in the aged individuals. This study is a first attempt to investigate the effects of both noise and ageing on zebrafish behaviour, suggesting the age-dependent physiological coping mechanisms associated with environmental stress. [ABSTRACT FROM AUTHOR]

Main conclusion: Specific sound patterns can affect plant development. Plants are responsive to environmental stimuli such as sound. However, little is known about their sensory apparatus, mechanisms, and signaling pathways triggered by these stimuli. Thus, it is important to understand the effect of sounds on plants and their technological potential. This review addresses the effects of sounds on plants, the sensory elements inherent to sound detection by the cell, as well as the triggering of signaling pathways that culminate in plant responses. The importance of sound standardization for the study of phytoacoustics is demonstrated. Studies on the sounds emitted or reflected by plants, acoustic stress in plants, and recognition of some sound patterns by plants are also explored. [ABSTRACT FROM AUTHOR]

Anthropogenic noise has been related to stress in captive animals; despite this there have been few studies on animal welfare assessment in walk-through zoo enclosures. We aimed to investigate the behavioural effects of noise on a male-female pair of two-toed sloths (Choloepus didactylus), housed in a walk-through enclosure in a zoo in the UK. The animals were filmed for 24 h per day, during three days per week, including days with potential low and high flow of visitors, for three weeks. Sound pressure measurement was performed four times each collection day (twice in the morning, once at noon and once in the afternoon), for 15 min per session, using a sound level meter. The number of visitors passing the enclosure during each session was also recorded. The videos were analysed using focal sampling, with continuous recording of behaviour. Correlations between noise and the behaviours expressed during, and in the 24 h after the acoustic recording, were investigated. The number of visitors correlated with the acoustic parameters. At the moment of exposure, higher levels of noise correlated with decreased inactivity, and longer expression of locomotion and maintenance behaviours for the male; the female spent more time inside a box in these moments. During the 24 h hours after exposure to loud noise, the female showed no behavioural changes while the male tended to reduce foraging. The behavioural changes observed in both individuals have already been reported in other species, in response to stressful events. Our study indicates the need for a good acoustic management in walk-through zoo enclosures where sloths are housed.

Football matches, as a common urban activity, produce high levels of noise because of vehicular traffic, screams, whistles, and firework displays. Fear of noise is one of the most commonly reported behavior problems in dogs (Canis familiaris); however, few studies have focused on the effects of repeated exposition to noise in these animals. Here, we investigated whether the noise produced during football matches may act as a stress source for dogs living near football stadiums. We measured noise levels on days with and without matches, in the surrounding neighborhoods of two football stadiums of Minas Gerais, Brazil: (a) Arena Independência (AI) and (b) Governador Magalhães Pinto (GMP). Noise measurements were carried out by using a sound level meter, in distances varying between 0 and 400 m from the stadiums. A structured interview was conducted to dog owners living nearby AI, about the dogs' characteristics, demographics, and behavior. Noise records of days with and without matches were compared, and questionnaires were analyzed (general linear models) to identify possible correlations between the reported changes in the animals' behaviors on days with football matches and the distance these animals lived from the stadium. Higher noise levels were recorded on football match days than on days without matches, with a greater effect of these between 0 and 249 m (D1) than between 250 and 400 from AI. Around Governador Magalhães Pinto, we recorded greater noise levels on days without football matches compared with match days, with no difference between distances. Fear/anxiety behaviors were reported as more intense on days with football matches, in comparison with days without matches for 90.6% of the study dogs. The occurrence of matches made specific fear-related behaviors of the dogs—severe trembling, excessive salivation, agitation/restlessness, whining, and appetite loss—more frequent. The proximity of AI intensified the exhibition of general fear/anxiety behaviors and made intense trembling and excessive salivation more frequent at D1, in relation to D2. On the other hand, dogs living at D2 barked, howled, and lost appetite more often than those living at D1. Our results suggested a detrimental influence of noise from football matches on the behavior of dogs living around football stadiums. These data are relevant for public policy-making to promote preventive and mitigating measures, to improve the quality of life of both the dog and the human populations in the surroundings of football stadiums. [ABSTRACT FROM AUTHOR]

Seismic surveys map the seabed using intense, low-frequency sound signals that penetrate kilometers into the Earth's crust. Little is known regarding how invertebrates, including economically and ecologically important bivalves, are affected by exposure to seismic signals. In a series of field-based experiments, we investigate the impact of exposure to seismic surveys on scallops, using measurements of physiological and behavioral parameters to determine whether exposure may cause mass mortality or result in other sublethal effects. Exposure to seismic signals was found to significantly increase mortality, particularly over a chronic (months postexposure) time scale, though not beyond naturally occurring rates of mortality. Exposure did not elicit energetically expensive behaviors, but scallops showed significant changes in behavioral patterns during exposure, through a reduction in classic behaviors and demonstration of a nonclassic "flinch" response to air gun signals. Furthermore, scallops showed persistent alterations in recessing reflex behavior following exposure, with the rate of recessing increasing with repeated exposure. Hemolymph (blood analog) physiology showed a compromised capacity for homeostasis and potential immunodeficiency, as a range of hemolymph biochemistry parameters were altered and the density of circulating hemocytes (blood cell analog) was significantly reduced, with effects observed over acute (hours to days) and chronic (months) scales. The size of the air gun had no effect, but repeated exposure intensified responses. We postulate that the observed impacts resulted from high seabed ground accelerations driven by the air gun signal. Given the scope of physiological disruption, we conclude that seismic exposure can harm scallops. [ABSTRACT FROM AUTHOR]

The protective effect of cortexin was investigated with the use of acoustic stress hemorrhagic stroke model. A significant decrease of 8-oxo-2'-deoxyguanosine to 2'-deoxyguanosine ratio in the DNA molecule was shown using brain slices of cortexin treated Krushinsky-Molodkina rats.

In this study, our hypothesis was that workplace noise can alter brain element levels like immobilization and light-dark cycle shift, and we aimed to investigate the effects of workplace noise on element levels of brain areas as well as changes in blood of chronically noise-exposed rats. Twenty-four rats were randomly divided into three groups. The first group was the control. The second group (noise exposed) was subjected to daily 8 h 85 dB workplace noise for 15 days, and the third group (noise exposed plus normal condition) was also subjected to the same noise exposure and then returned to normal condition for 15 days. In noise-exposed group, Na, K, Ca, Mg , Fe, Cu, and Zn levels in plasma significantly increased when compared with controls ( p = 0.03 for Na; p = 0.005 for K and Mg; p = 0.002 for Ca and Fe; p = 0.01 for Cu and Zn). In this group, Fe level of temporal lobe significantly increased ( p = 0.021) while Mg level significantly increased in frontal ( p = 0.021) and temporal ( p = 0.001) lobes when compared with controls. In the noise-exposed plus normal condition group, plasma Na, K, Fe, Cu, and Zn levels were greatly similar to controls. But, plasma Ca and Mg levels significantly decreased when compared with controls ( p = 0.002 and p = 0.007) and noise-exposed group ( p = 0.002 and p = 0.001). Fe level of temporal lobe significantly increased when compared with controls ( p = 0.001) and noise exposed group ( p = 0.001). These alterations may be attributed to impaired intake of water and micronutrients or their excretions, emerging by acoustic stress. [ABSTRACT FROM AUTHOR]

This study examined the effects of an acoustic stimulus on the haemolymph and agonistic behaviour of the red swamp crayfish, Procambarus clarkii. The experiment was conducted in a tank equipped with a video recording system using six groups (three control and three test groups) of five adult crayfish (30 specimens in total). After 1 h of habituation, the behaviour of the crayfish was monitored for 2h. During the second hour, the animals in the test groups were exposed to a linear sweep (frequency range 0.1-25kHz; peak amplitude l48dBrmsre. 1 μPa at 12kHz) acoustic stimulus for 30mm. Exposure to the noise produced significant variations in haemato-immunological parameters as well as a reduction in agonistic behaviour. Key words: acoustic stress. aaonistic behaviour. ohvsioloaical resoonse. red swamo crayfish [ABSTRACT FROM AUTHOR]

Strong acoustic stimulation (105 dB SPL white noise) elicited c-fos expression in neurons in several acoustic system nuclei and in stress-sensitive hypothalamic nuclei and limbic areas in rats. In the present study, using this type of loud noise for 30 min, Fos-like immunoreactivity (Fos-ir) was investigated in neurons that synthesize tuberoinfundibular peptide of 39 residues (TIP39) in the rat brain: in the subparafascicular area of the thalamus, the posterior intralaminar complex of the thalamus and the medial paralemniscal nucleus in the lateral part of the pons. By double labeling, Fos-ir was shown in nearly 80% of TIP39-positive cells in the medial paralemniscal nucleus, 43% in the posterior intralaminar complex and 18.5% in the subparafascicular area 30 min after the end of a 30-min loud noise period. In control rats, only few neurons, including 0–4% of TIP39-positive neurons showed Fos-ir. While the majority of the Fos-ir neurons were TIP39-positive in the subparafascicular area and medial paralemniscal nucleus, a fairly high number of TIP39-immunonegative, chemically uncharacterized neurons expressed c-fos in the subparafascicular area and the posterior intralaminar complex of the thalamus. These observations clearly show that some TIP39 neurons in the so-called “acoustic thalamus” and the majority of TIP39 neurons in the medial paralemniscal nucleus are sensitive to loud noise and they may participate in the central organization of responses to acoustic stress. Furthermore, the present data suggest that non-TIP39-expressing neurons may play a prevalent role in the activity of the “acoustic thalamus”. [ABSTRACT FROM AUTHOR]

Abstract: Exposure of rats to unpredictable loud sound pulses increases activity of the rate-limiting enzyme for serotonin synthesis, tryptophan hydroxylase (TPH), in the median raphe nucleus (MnR) and a mesolimbocortical serotonergic system. Corticotropin-releasing factor (CRF)-induced activation of a subset of serotonergic neurons in the caudal dorsal raphe nucleus (DR) may underlie stress-related increases in TPH activity in the MnR and a mesolimbocortical serotonergic system. An in vivo acoustic stimulation paradigm and an in vitro brain slice preparation were designed to test the hypothesis that stress-related stimuli and CRF receptor activation have convergent actions on TPH activity in the caudal DR (DRC). We measured 5-hydroxytryptophan (5-HTP) accumulation as an index of TPH activity following inhibition of aromatic amino acid decarboxylase (using NSD-1015). To examine effects of acoustic stimulation on TPH activity, male Wistar rats, pretreated with NSD-1015, were exposed to a 30min sham, predictable or unpredictable acoustic stimulation paradigm; brains were frozen and microdissected for analyses of tissue 5-HTP concentrations in subregions of the DR. To examine the effect of CRF receptor activation on TPH activity, freshly prepared brain slices were exposed to CRF (0–2000nM) for 10min in the presence of NSD-1015, then frozen and microdissected for analysis of tissue 5-HTP concentrations. Increases in TPH activity in the DRC, but not other subregions, were observed in both paradigms. These findings are consistent with the hypothesis that stress-related increases in TPH activity are mediated via effects of CRF or CRF-related neuropeptides on a mesolimbocortical serotonergic system originating in the DRC. [Copyright &y& Elsevier]

Marine environments have suffered from a lack of quantitative methods for delineating areas that are sensitive or vulnerable to particular stresses, natural and anthropogenic. We define sensitivity as the degree to which marine features respond to stresses, which are deviations of environmental conditions beyond the expected range. Vulnerability can then be defined as the probability that a feature will be exposed to a stress to which it is sensitive. Using these definitions, we provide a quantitative methodology for identifying vulnerable marine areas based on valued ecological features, defined as biological or physical features, processes, or structures deemed by humans to have environmental, social, cultural, or economic significance. The vulnerability of the valued ecological features is a function of their sensitivity to particular stresses and their vulnerability to those stresses. We used the methodology to demonstrate how vulnerable marine areas for two groups of endangered whale species (inshore and offshore) could be identified with a predictive habitat model and acoustic stress surfaces. Acoustic stress surfaces were produced for ferry traffic, commercial shipping traffic, potential offshore oil production, and small-boat traffic. The vulnerabilities of the two whale groups to the four stressors considered in this example were relatively similar; however, inshore species were more sensitive to on-shelf, coastal activities such as offshore hydrocarbon production, ferry traffic, and small-boat traffic. Our approach demonstrates how valued features can be associated with stresses and the likelihood of encountering these stresses (vulnerability) in order to identify geographic areas for management and conservation purposes. The method can be applied to any combination of valued ecological features and stressors. [ABSTRACT FROM AUTHOR]

A variety of approaches have been developed to release contents from capsules, including techniques that use electric or magnetic fields, light, or ultrasound as a stimulus. However, in the majority of the known approaches, capsules are disintegrated in violent way and the liberation of the encapsulated material is often in a random direction. Thus, the controllable and direction-specific release from microcapsules in a simple and effective way is still a great challenge. This greatly limits the use of microcapsules in applications where targeted and directional release is desirable. Here, we present a convenient ultrasonic method for controllable and unidirectional release of an encapsulated substance. The release is achieved by using MHz-frequency ultrasound that enables the inner liquid stretching, which imposes mechanical stress on the capsule's shell. This leads to the puncturing of the shell and enables smooth liberation of the liquid payload in one direction. We demonstrate that 1-4.3 MHz acoustic waves with the intensity of a few W/cm 2 are capable of puncturing of particle capsules with diameters ranging from around 300 μm to 5 mm and the release of the encapsulated liquid in a controlled manner. Various aspects of our route, including the role of the capsule size, ultrasound wavelength, and intensity in the performance of the method, are studied in detail. We also show that the additional control of the release can be achieved by using capsules having patchy shells. The presented method can be used to facilitate chemical reactions in micro- and nanolitre droplets and various small-scale laboratory operations carried in bulk liquids in microenvironment. Our results may also serve as an entry point for testing other uses of the method and formulation of theoretical modeling of the presented ultrasound mechanism.

The effect of circulation arrest on the development of stress-induced injuries was studied in Krushinsky—Molodkina rats genetically predisposed to audiogenic seizure. Resuscitated rats were subjected to acoustic stress 1.5 month after circulation arrest. The severity of neurological disorders and the frequency and severity of intracranial hemorrhages increased, while excitability of the central nervous system remained unchanged during stress. Thus, the resistance to stress considerably decreased in rats survived a short-term circulatory arrest due to dysfunction of the autonomic nervous regulation of hemodynamics rather than enhanced excitability of the central nervous system. [ABSTRACT FROM AUTHOR]

The paper reports the results of an experimental seismic survey in the open sea by an air gun, carried out to evaluate the effects of airgun acoustic waves on marine animals. Air gun blast exposition was found to have a marked influence on confined Dicentrarchus labrax. Ourdata, in fact, demonstrated a biochemical response to acoustic stress induced by air gun blasts. Variations of cortisol, glucose, lactate, AMP, ADP, ATP and cAMP in different tissues of D. labrax, indicate that fish have a typical primary and secondary stress response after air gun detonations. Radiography indicates that air gun blasts do notinduce any macroscopic effect on skeletal apparatus. The variations of biochemical parameters returned within physiological values within72 h indicating a rapid recovery of homeostasis after acoustic stress and no mortality was observed. [ABSTRACT FROM AUTHOR]