Robust maneuverability in flipper-based systems across complex terrains

Aquatic resources are one of the natural resources that can be renewed, but if their use is carried out excessively without paying attention to sustainability, it will have a bad impact on the aquatic resources themselves. This study discusses policies related to sea turtle conservation activities, the purpose of this study is to find out the policies that have been made related to sea turtle conservation and its implementation in the field, this is done to realize the sustainability of resources and the aquatic environment. This study was conducted in the Nipah Essential Ecosystem Area (KEE), Malaka Village, North Lombok, West Nusa Tenggara. The existence of this ecosystem area can directly or indirectly help in natural resource conservation activities in the Nipah coastal environment. One of the policies that have been implemented to preserve turtle habitat is by conserving sea turtle habitat, and educational activities on the importance of sea turtles for natural resources and the aquatic environment. Conservation activities carried out in the Nipah Essential Ecosystem Area (KEE) have an implementation score of 100% meaning that policies related to sea turtle conservation in the Nipah Essential Ecosystem Area have been implemented properly, this happens because of the cooperation of various parties between local communities, the TCC (Turtle Conservation Community) community, local governments, and the central government. With a high implementation score, sea turtle habitats will be better preserved, and natural resources and aquatic environments will become sustainable.

In this study the performance of the Weather Research and Forecast (WRF) model in a complex and coastal terrain has been evaluated with focus on wind resource assessment. The study area is a small community on the northern part of the island Senja, Norway. The community, with fishery and seafood as its main industry, is being limited by poor grid connection. One of the solutions is to increase the production of local power from wind energy. There are no in-situ wind measurements in the area, and therefore numerical weather prediction models, namely the WRF model, is being evaluated as a method for wind resource assessment. The WRF model has been run for the whole of 2017 with high resolution covering an area large enough to include the three closest weather stations. The model is compared to the observed wind speed and direction. It is found that the model is able to reproduce the average wind speed and wind direction quite well for two of the locations, while for the third location the average wind speed is considerably overestimated compared to the observations. The Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) found are larger than in other comparable studies.

Lunar rover is a special kind of wheeled mobile robot for deep space exploration mission. On the moon, the soft weathered layers, as well as different sizes of rocks and craters, are distributed disorderly and unsystematically. Facing such kinds of complex environments and terrains, the mobility and terrain trafficability performance of the lunar rover will be threatened to a certain extent. The SpaceDyn toolbox is adopted to build the six-wheeled lunar rover kinematics relation and to calculate the kinetic parameters. Then the lunar rover dynamics model can be achieved. The wheel-soil interaction model on soft terrain is established based on terramechanics theory. Finally, the coordinated driving controller for the six-wheeled lunar rover on complex soft terrain is designed according to the above model. Numerical calculation and computer simulations are performed to verify the performance of the designed controller on soft terrain. Results indicate that the lunar rover has a better coordination driving control ability when using the designed controller, which may provide a reference for motion control of other kinds of wheeled mobile robot.

A field study of dispersion using tracer gases from offshore sources into severe coastal complex terrain was conducted in central California. Data were collected on dispersion, surface concentrations trajectories, and stability. An examination of the data has shown that a zone of stagnation extends well offshore causing unusual plume behaviors including evidence of bimodal concentration distributions in the horizontal. A conceptual model based on a Gaussian model is formulated to describe the observed behavior and is compared to actual surface tracer PS concentrations in the coastal terrain.

Salmonellae are Gram-negative zoonotic bacteria that are frequently part of the normal reptilian gastrointestinal flora. The main objective of this project was to estimate the prevalence of non-typhoidal Salmonella enterica in the nesting and foraging populations of sea turtles on St. Kitts and in sand from known nesting beaches. Results suggest a higher prevalence of Salmonella in nesting leatherback sea turtles compared with foraging green and hawksbill sea turtles. Salmonella was cultured from 2/9 and identified by molecular diagnostic methods in 3/9 leatherback sea turtle samples. Salmonella DNA was detected in one hawksbill turtle, but viable isolates were not recovered from any hawksbill sea turtles. No Salmonella was detected in green sea turtles. In samples collected from nesting beaches, Salmonella was only recovered from a single dry sand sample. All recovered isolates were positive for the wzx gene, consistent with the O:7 serogroup. Further serotyping characterized serovars Montevideo and Newport present in cloacal and sand samples. Repetitive-element palindromic PCR (rep-PCR) fingerprint analysis and pulsed-field gel electrophoresis of the 2014 isolates from turtles and sand as well as archived Salmonella isolates recovered from leatherback sea turtles in 2012 and 2013, identified two distinct genotypes and four different pulsotypes, respectively. The genotyping and serotyping were directly correlated. To determine the persistence of representative strains of each serotype/genotype in these environments, laboratory-controlled microcosm studies were performed in water and sand (dry and wet) incubated at 25 or 35°C. Isolates persisted for at least 32days in most microcosms, although there were significant decreases in culturable bacteria in several microcosms, with the greatest reduction in dry sand incubated at 35°C. This information provides a better understanding of the epizootiology of Salmonella in free-ranging marine reptiles and the potential public health risks associated with human interactions with these animals in the Caribbean.

Review of potential impacts to sea turtles from underwater explosive removal of offshore structures

All-terrain microrobots possess significant potential in modern medical applications due to their superior maneuverability in complex terrains and confined spaces. However, conventional microrobots often struggle with adaptability and operational difficulties in variable environments. This study introduces a magnetic torque-driven all-terrain multiped microrobot (MTMR) to address these challenges. By coupling the structure's multiple symmetries with different uniform magnetic fields, such as rotating and oscillating fields, the MTMR demonstrates various locomotion modes, including rolling, tumbling, walking, jumping, and their combinations. Experimental results indicate that the robot can navigate diverse terrains, including flat surfaces, steep slopes (up to 75°), and gaps over twice its body height. Additionally, the MTMR performs well in confined spaces, capable of passing through slits (0.1 body length) and low tunnels (0.25 body length). The robot shows potential for clinical applications like minimally invasive hemostasis in internal bleeding and thrombus removal from blood vessels through accurate cargo manipulation capability. Moreover, the MTMR can carry temperature sensors to monitor environmental temperature changes in real time while simultaneously manipulating objects, displaying its potential for in-situ sensing and parallel task implementation. This all-terrain microrobot technology demonstrates notable adaptability and versatility, providing a solid foundation for practical applications in interventional medicine.

Sea turtles are basically creatures that spend their entire lives in marine or estuarine habitats. Their only remaining reptilian ties to terrestrial habitats are for nesting and restricted cases of basking. Consequently, physiological, anatomical, and behavioral adaptations have evolved largely in response to selection in the aquatic environment, and sea turtles share many common elements with larger fishes and cetaceans in their habitat utilization and migrations. A generalized habitat model may be constructed for sea turtles based on ontogenetic stages: early juvenile nursery habitat, later juvenile developmental habitat, adult foraging habitat, and adult inter-nesting and/or breeding habitat. In sea turtles as in fishes, the numbers and diversity of potential predators and resulting mortality rates are inversely proportional to the size of the juvenile. The advantage of pelagic, oceanic nurseries is the low density of predatory fishes and sea birds there dictated by low primary production.

Robots are becoming increasingly essential for traversing complex environments such as disaster areas, extraterrestrial terrains, and marine environments. Yet, their potential is often limited by mobility and adaptability constraints. In nature, various animals have evolved finely tuned designs and anatomical features that enable efficient locomotion in diverse environments. Sea turtles, for instance, possess specialized flippers that facilitate both long-distance underwater travel and adept maneuvers across a range of coastal terrains. Building on the principles of embodied intelligence and drawing inspiration from sea turtle hatchings, this paper examines the critical interplay between a robot’s physical form and its environmental interactions, focusing on how morphological traits and locomotive behaviors affect terrestrial navigation. We present a bioinspired robotic system and study the impacts of flipper/body morphology and gait patterns on its terrestrial mobility across diverse terrains ranging from sand to rocks. Evaluating key performance metrics such as speed and cost of transport, our experimental results highlight adaptive designs as crucial for multi-terrain robotic mobility to achieve not only speed and efficiency but also the versatility needed to tackle the varied and complex terrains encountered in real-world applications.

A dispersion modeling system consisting of a three-dimensional PBL model NHECM (non-hydrostaticE-e closure model) and SLPTDM (seven-level puff transport and diffusion model) is developed to simulate the transport and dispersion of pollutant over coastal complex terrain. As an application of the system, the transport and dispersion of SO2 released from an elevated point source are simulated during typical sea-land breeze circulation in the Hongkong-Shenzhen area of China. The NHECM provides time-varying, three-dimensional distributions of wind and turbulence fields to the SLPTDM. The NHECM predictions compare well with observational data. Reflection of both the ground and the mixing layer top and penetration of the mixing layer top are improved in the SLPTDM. Results obtained from the system indicate that temporal variation and nonuniformity of airflow and turbulence obviously affect the concentration distributions, especially during the sea-land breeze transition period. A diurnal cycle of the GLC (ground-level concentration) is discussed. The results are compared with those estimated using a Gaussian model. The study's results illustrate the complexity of the dispersion patterns due to diurnal effects and mesoscale circulations, and demonstrate the potential of the mesoscale atmospheric dispersion modeling system for studies of air quality in complex terrain.

Simple SummaryEmerging environmental contaminants, such as sunscreen agents, have been broadly identified in marine ecosystems. Thus, the present work aims to investigate whether organic UV filters cause immunotoxic effects in juvenile loggerhead sea turtles (Caretta caretta). We found that loggerhead sea turtles showing high circulating levels of organic UV filters manifested increased expression of genes involved in inflammatory responses, probably due to contaminant-induced oxidative damage.Recent evidence suggests that exposure to organic ultraviolet filters (UV filters) is associated with dysregulated neuroendocrine-immune homeostasis. Marine species are likely to be among the most vulnerable to UV filters due to widespread diffusion of these chemicals in the aquatic environment. In the present study, the effects of UV filter bioaccumulation on toll-like-receptors (TLRs) and related signaling pathways were investigated in peripheral blood mononuclear cells (PBMCs) of juvenile loggerhead sea turtles (Caretta caretta). We found that the expression of both TLR1 and TLR2 was significantly increased in UV-filter exposed turtles compared to control animals. Similarly, the signaling pathway downstream of activated TLRs (i.e., Ras-related C3 botulinum toxin substrate 1 (RAC1), Phosphoinositide 3-kinase (PI3K), serine/threonine-protein kinase (AKT3), and nuclear factor κB (NF-κB)) was significantly up-regulated, leading to an enhanced transcription of pro-inflammatory cytokines. In addition, we demonstrated that high levels of plasma UV filters increased lipid peroxidation in sea turtles’ PBMCs. Our results indicated that UV filters affected the inflammatory responses of PBMCs via modulation of the TLR/NF-κB signaling pathway and provided a new insight into the link between exposure to sunscreen agents and sea turtle health.

Sea turtles spend much of their life in aquatic environments, but critical portions of their life cycle, such as nesting and hatching, occur in terrestrial environments, suggesting that it may be important for them to detect sounds in both air and water. In this study we compared underwater and aerial hearing sensitivities in five juvenile green sea turtles (Chelonia mydas) by measuring auditory evoked potential responses to tone pip stimuli. Green sea turtles detected acoustic stimuli in both media, responding to underwater stimuli between 50 and 1600 Hz and aerial stimuli between 50 and 800 Hz, with maximum sensitivity between 200 and 400 Hz underwater and 300 and 400 Hz in air. When underwater and aerial hearing sensitivities were compared in terms of pressure, green sea turtle aerial sound pressure thresholds were lower than underwater thresholds, however they detected a wider range of frequencies underwater. When thresholds were compared in terms of sound intensity, green sea turtle sound intensity level thresholds were 2–39 dB lower underwater particularly at frequencies below 400 Hz. Acoustic stimuli may provide important environmental cues for sea turtles. Further research is needed to determine how sea turtles behaviorally and physiologically respond to sounds in their environment.

Lidar ceilometer observations and modeling of a fireworks plume in Vancouver, British Columbia

Utilizing hourly observational data from automatic weather stations across Fujian Province from 2008 to 2020, this study defined and classified concepts and thresholds for convective precipitation, short-duration convective precipitation, long-duration convective precipitation, localized heavy precipitation, and widespread heavy precipitation. We explored the fundamental diurnal climatic characteristics of convective precipitation during the flood season in Fujian Province’s complex terrain. The results indicate the following. 1) Convective precipitation during the flood season exhibits distinct diurnal variation, with a significant spatial distribution along mountainous and coastal terrains. 2) The frequency of precipitation during the pre-flood season is higher and its intensity is lower than in the post-flood season. Due to differing primary weather systems influencing each period, resulting in substantial differences in the spatial distribution of precipitation frequency and intensity. 3) Both short-duration and localized precipitation show pronounced afternoon peaks in their diurnal patterns, predominantly occurring on windward slopes, highlighting mechanisms of afternoon moist convection and orographic lifting, whereas long-duration and widespread precipitation lack diurnal variation, reflecting the influence of large-scale circulation. These results will help forecasters better understand the unique precipitation characteristics of Fujian Province.

AimIdentifying processes that determine climatic niche dynamics is difficult, especially for wide‐ranging species where niche conservatism might differ at different life stages. Evolutionary history shapes climatic niche, with populations of the same or phylogenetically close species occupying similar conditions. However, the geographical separation of populations also leads to niche evolution as an adaptive response to local conditions. Here, we use five sea turtle species (loggerhead, green, leatherback, hawksbill, olive ridley) to test whether short‐ (environmental adaptation) or long‐term (phylogenetic separation) evolutionary events determined the level of niche conservatism among distinct groups of nesting populations (termed Regional Management Units; RMUs) distributed across different ocean basins.LocationGlobal.MethodsWe estimated the climatic niche of 4,829 georeferenced nesting locations using air and sea surface parameters. We quantified niche overlap among RMUs of the same species at a global scale and examined how the geographical ranges of each RMU are correlated with niche similarity. We also investigated the extent of niche conservatism among RMUs of different species in the same ocean basin.ResultsWe found limited within‐species niche similarity of RMUs at a global scale, with geographical range having negligible impact (latitudinal overlap, range size asymmetries). We detected generally higher niche overlap between RMUs of different species located within the same ocean basin, where the geographical range had a stronger effect on niche similarity.Main conclusionsWe show that adaptation to local conditions potentially prevails over distant evolutionary events when considering the climatic niche of RMUs of the same species across different oceans. Because sea turtles, like other long‐distance migratory animals, occupy distinct climatic niches, our findings support the importance of understanding this phenomenon for different life stages, populations and species to preserve unique adaptations to different environments that might enhance future viability under climate change, as well as help identify key conservation areas.