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Many animals and plants have species-typical annual cycles, but individuals vary in their timing of life-history events. Individual variation in fur replacement (moult) timing is poorly understood in mammals due to the challenge of repeated observations and longitudinal sampling. We examined factors that influence variation in moult duration and timing among elephant seals (Mirounga angustirostris). We quantified the onset and progression of fur loss in 1178 individuals. We found that an exceptionally rapid visible moult (7 days, the shortest of any mammals or birds), and a wide range of moult start dates (spanning 6-10× the event duration) facilitated high asynchrony across individuals (only 20% of individuals in the population moulting at the same time). Some of the variation was due to reproductive state, as reproductively mature females that skipped a breeding season moulted a week earlier than reproductive females. Moreover, individual variation in timing and duration within age-sex categories far outweighed (76-80%) variation among age-sex categories. Individuals arriving at the end of the moult season spent 50% less time on the beach, which allowed them to catch up in their annual cycles and reduce population-level variance during breeding. These findings underscore the importance of individual variation in annual cycles.

BACKGROUND: Elephant seals exhibit extreme hypoxemic tolerance derived from repetitive hypoxia/reoxygenation episodes they experience during diving bouts. Real-time assessment of the molecular changes underlying protection against hypoxic injury in seals remains restricted by their at-sea inaccessibility. Hence, we developed a proliferative arterial endothelial cell culture model from elephant seals and used RNA-seq, functional assays, and confocal microscopy to assess the molecular response to prolonged hypoxia. RESULTS: Seal and human endothelial cells exposed to 1% O2 for up to 6 h respond differently to acute and prolonged hypoxia. Seal cells decouple stabilization of the hypoxia-sensitive transcriptional regulator HIF-1α from angiogenic signaling. Rapid upregulation of genes involved in glutathione (GSH) metabolism supports the maintenance of GSH pools, and intracellular succinate increases in seal but not human cells. High maximal and spare respiratory capacity in seal cells after hypoxia exposure occurs in concert with increasing mitochondrial branch length and independent from major changes in extracellular acidification rate, suggesting that seal cells recover oxidative metabolism without significant glycolytic dependency after hypoxia exposure. CONCLUSIONS: We found that the glutathione antioxidant system is upregulated in seal endothelial cells during hypoxia, while this system remains static in comparable human cells. Furthermore, we found that in contrast to human cells, hypoxia exposure rapidly activates HIF-1 in seal cells, but this response is decoupled from the canonical angiogenesis pathway. These results highlight the unique mechanisms that confer extraordinary tolerance to limited oxygen availability in a champion diving mammal.

Populations and species are threatened by human pressure, but their fate is variable. Some depleted populations, such as that of the northern elephant seal (Mirounga angustirostris), recover rapidly even when the surviving population was small. The northern elephant seal was hunted extensively and taken by collectors between the early 1800s and 1892, suffering an extreme population bottleneck as a consequence. Recovery was rapid and now there are over 200,000 individuals. We sequenced 260 modern and 8 historical northern elephant seal nuclear genomes to assess the impact of the population bottleneck on individual northern elephant seals and to better understand their recovery. Here we show that inbreeding, an increase in the frequency of alleles compromised by lost function, and allele frequency distortion, reduced the fitness of breeding males and females, as well as the performance of adult females on foraging migrations. We provide a detailed investigation of the impact of a severe bottleneck on fitness at the genomic level and report on the role of specific gene systems.

Deep ocean foraging northern elephant seals (Mirounga angustirostris) consume fish and squid in remote depths of the North Pacific Ocean. Contaminants bioaccumulated from prey are subsequently transferred by adult females to pups during gestation and lactation, linking pups to mercury contamination in mesopelagic food webs (200-1000 m depths). Maternal transfer of mercury to developing seal pups was related to maternal mercury contamination and was strongly correlated with maternal foraging behavior (biotelemetry and isotopes). Mercury concentrations in lanugo (hair grown in utero) were among the highest observed worldwide for young pinnipeds (geometric mean 23.01 μg/g dw, range 8.03-63.09 μg/g dw; n = 373); thus, some pups may be at an elevated risk of sub-lethal adverse health effects. Fetal mercury exposure was affected by maternal foraging geographic location and depth; mercury concentrations were highest in pups of the deepest diving, pelagic females. Moreover, pup lanugo mercury concentrations were strongly repeatable among successive pups of individual females, demonstrating relative consistency in pup mercury exposure based on maternal foraging strategies. Northern elephant seals are biosentinels of a remote deep-sea ecosystem. Our results suggest that mercury within North Pacific mesopelagic food webs may also pose an elevated risk to other mesopelagic-foraging predators and their offspring.

For DanaIt is often forgotten that a variety of French peculiar to the British Isles, known as Anglo-Norman was, for more than four centuries post-Conquest, the default language for inscriptions of an amatory nature, on jewellery especially. The large number of inscribed rings, brooches and seal matrices unearthed by metal-detectorists in recent decades whose finds are recorded in detail on the Portable Antiquities Scheme (PAS) database have prompted this consideration of these legends — often simple rhyming couplets or 'posies' — especially in the context of that set of romantic conventions retrospectively termed 'Courtly Love'.1 [ABSTRACT FROM AUTHOR]

The paper considers the appearance and meaning of city walls on ducal and municipal seals in 13th-century Poland. Despite the great popularity of the motif, actual stone or brick fortifications, both of towns and castles, were rare in Poland at the time. It is especially striking that in the area of Kuyavia, where local dukes introduced the motif onto their seals at an early stage, such architectonic structures were almost entirely absent. Several towns also employed images of stone walls on their seals before they gained the real fortifications. The motif of fortification is examined here as a symbol of civilization in a wider sense, and particularly that of the communal town. The final section the paper explores ways in which Polish society might have come to understand this symbolism. [ABSTRACT FROM AUTHOR]

Failures in hydraulic systems in offshore wind turbines represent an enormous challenge for manufacturers and operators, as the pitch system statistically is one of the subsystems contributing the most to the downtime of the turbines, which is the case for both electrical and hydraulic pitch systems. However, the complex failure mechanisms of the various different hydraulic components mean that, typically, the critical components of hydraulic systems must be tested to better understand the failure mechanisms. Nonetheless, conventional testing procedures are lengthy and costly. Accelerated testing plays a critical role as it can mimic hydraulic system failure mechanisms in a shorter period. However, the lack of standardized test methods and detailed knowledge about the failure-accelerating effects complicates the process. Therefore, this paper offers a comprehensive examination of approaches applicable to conducting accelerated tests on hydraulic systems. It identifies and discusses five primary component types or sub-components related to the acceleration of testing in hydraulic systems: pumps, cylinders, seals, valves, and hoses. Each section references studies that delve into accelerated testing methodologies for these individual components. Furthermore, within each component, a concise overview of the current techniques is provided, followed by a discussion and summary based on the state of the art. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza A(H5N1) virus was detected in dead seals on Tyuleniy Island in eastern Russia, in the Sea of Okhotsk. Viruses isolated from dead northern fur seals belong to clade 2.3.4.4b and are closely related to viruses detected predominantly in the Russian Far East and Japan in 2022–2023.

Failures in hydraulic systems in offshore wind turbines represent an enormous challenge for manufacturers and operators, as the pitch system statistically is one of the subsystems contributing the most to the downtime of the turbines, which is the case for both electrical and hydraulic pitch systems. However, the complex failure mechanisms of the various different hydraulic components mean that, typically, the critical components of hydraulic systems must be tested to better understand the failure mechanisms. Nonetheless, conventional testing procedures are lengthy and costly. Accelerated testing plays a critical role as it can mimic hydraulic system failure mechanisms in a shorter period. However, the lack of standardized test methods and detailed knowledge about the failure-accelerating effects complicates the process. Therefore, this paper offers a comprehensive examination of approaches applicable to conducting accelerated tests on hydraulic systems. It identifies and discusses five primary component types or sub-components related to the acceleration of testing in hydraulic systems: pumps, cylinders, seals, valves, and hoses. Each section references studies that delve into accelerated testing methodologies for these individual components. Furthermore, within each component, a concise overview of the current techniques is provided, followed by a discussion and summary based on the state of the art.

Clay sealings (cretulae) have traditionally been assumed to have been used in ancient administrative systems to secure the shipment of commodities and to account for their receipt. However, research in Western Asia has revealed that they were primarily used as a complex administrative tool in the management of storehouses and the goods they contained, ensuring the personal accountability of the individuals under whose seal or combination of seals particular items were stored. Although stamp seals are relatively common finds in the Indus Civilization, clay sealings are not as numerous as in contemporaneous sites throughout Western Asia. This rarity has led to speculation about the actual use of seals in the Indus Civilization. However, the study of an exceptional assemblage of clay sealings found at the Indus site of Lothal in Gujarat, India, has shed light on the function and use of these objects in the Indus Civilization. In particular, the stratigraphic analysis of the discovery context has made it possible to consider the existence of an administrative archive comparable to those excavated in Western Asia. [ABSTRACT FROM AUTHOR]

The working processes and integral characteristics of piston long-stroke low-speed compressor stages are considered. Well-known technologies for increasing the feed rate are considered as objects of comparison: selection of the main dimensions and parameters of the stage; changing the size and design of valves, using elastomeric structural materials; change in the design of the cylinder-piston seal; changing the layout of the suction valve in the working chamber. Indicator efficiency, supply coefficient and tightness coefficient, as well as discharge temperature are considered as integral indicators. The following independent parameters are considered: parameters of the state of the working fluid at suction, discharge pressure, main dimensions and parameters of the stage, distance from the suction valve to the top dead center, seat diameters of the suction and discharge valves, as well as physical and mechanical properties of structural materials. A comparative analysis of the efficiency of the working process of the stage under consideration is carried out using various technologies for reducing the intensity of mass transfer through leaks in the working chamber of a low-speed, long-stroke piston stage. An assessment is made of the achievable value of the feed coefficient with the combined use of various technologies. The features of the working processes of the object under consideration and the relationship between the intensity of mass flows of working gas through leaks in the working chamber of the stage and the technologies used have been studied. The presented results of the theoretical analysis reflect the nature of the change in the integral characteristics of the stage depending on the technologies used to reduce the intensity of mass transfer through leaks in the working chamber of the stage under consideration.

Social identity influences policy preferences and actions regarding wildlife. Using data from a survey of residents, commercial fishers, and tourists on Cape Cod, Massachusetts, this study examined the relationships between self-selected social identities (i.e., animal protection, environmental, hunter, and angler) within these stakeholder groups and ocean management priorities, support for the Marine Mammal Protection Act (MMPA), and acceptance of lethal management of seals and white sharks. Results revealed three social identity clusters: (1) identification with environmental and animal protection groups (non-consumptive), (2) identification with both non-consumptive (environmental, animal protection) and consumptive (angler, hunter) groups, and (3) identification with none of the groups. Residents were a mix of identities; tourists primarily identified with the non-consumptive and, to a lesser extent, no identification clusters; and commercial fishers identified with the mixed nonconsumptive/consumptive and no identification clusters. The overlap between consumptive and non-consumptive identifications illustrates the heterogeneity of social identity. Participants in the non-consumptive cluster favored policies prioritizing wildlife, the environment, and marine mammal protections more strongly than those in other clusters. Findings contribute to research examining social identity theory to improve understanding of public wildlife management preferences, within the novel context of rebounding populations of marine predators such as pinnipeds and white sharks. [ABSTRACT FROM AUTHOR]

Bijapur, now a district headquarters in Karnataka, was formerly the seat of the Adil Shahi kingdom of the Deccan which ruled the region for nearly two centuries (1489-1686 AD). The founder of the Adilshahi dynasty, Sultan Yusuf Adil Shah made Bijapur, or Vijyapur the capital of the Bijapur kingdom. The rulers of the Adilshahi dynasty ordered their engravers to engrave the seals in their names. We find many seals of this dynasty representing different rulers, princes, princesses, or officials. The seals of the Adil Shahi dynasty are very peculiar in many facets. Some important seals of the same period will be studied in this small article. [ABSTRACT FROM AUTHOR]

Understanding the tribological behavior of elastomers in dry conditions is essential for sealing applications, as dry contact may occur even in lubricated conditions due to local dewetting. In recent decades, Persson and co-authors have developed a comprehensive theory for rubber contact mechanics and dry friction. In this work, their model is implemented and extended, particularly by including static friction based on the bond population model by Juvekar and coworkers. Validation experiments are performed using a tribometer over a wide range of materials, temperatures and speeds. It is shown that the friction model presented in this work can predict the static and dynamic dry friction of various commercial rubber materials with different base polymers (FKM, EPDM and NBR) with an average accuracy of 10%. The model is then used to study the relevance of different elastomer friction contributions under various operating conditions and for different roughness of the counter surface. The present model will help in the development of novel optimized sealing solutions and provide a foundation for future modeling of lubricated elastomer friction. [ABSTRACT FROM AUTHOR]

There exists widespread evidence that the Near Eastern societies manufactured seals. However, among these, South Arabian seals remain largely neglected while performing various particularly revealing functions. For instance, the practice of sealing allowed for the explicit expression of ownership as well as the act of witnessing in legal matters. More broadly, seals were a means of articulating individual identities and reinforcing communal belonging. This paper is the first study on the seals of ancient South Arabia after the unpublished Ph.D. dissertation by Diana P. Wong (1999. "Stamp Seals of the Ancient Yemen." Unpublished PhD diss., Berkely). It investigates a corpus comprising 85 published seals currently held in museums and private collections across three continents. After providing a brief survey of the region's history, this article analyses the epigraphic and iconographic content carved on the corpus, offering some reflections on the typology and characteristics of the seals, as well as on the society of ancient South Arabia. [ABSTRACT FROM AUTHOR]

Sleep is a crucial part of the daily activity patterns of mammals. However, in marine species that spend months or entire lifetimes at sea, the location, timing, and duration of sleep may be constrained. To understand how marine mammals satisfy their daily sleep requirements while at sea, we monitored electroencephalographic activity in wild northern elephant seals (Mirounga angustirostris) diving in Monterey Bay, California. Brain-wave patterns showed that seals took short (less than 20 minutes) naps while diving (maximum depth 377 meters; 104 sleeping dives). Linking these patterns to accelerometry and the time-depth profiles of 334 free-ranging seals (514,406 sleeping dives) revealed a North Pacific sleepscape in which seals averaged only 2 hours of sleep per day for 7 months, rivaling the record for the least sleep among all mammals, which is currently held by the African elephant (about 2 hours per day).

Age determination of wild animals, including pinnipeds, is critical for accurate population assessment and management. For most pinnipeds, current age estimation methodologies utilize tooth or bone sectioning which makes antemortem estimations problematic. We leveraged recent advances in the development of epigenetic age estimators (epigenetic clocks) to develop highly accurate pinniped epigenetic clocks. For clock development, we applied the mammalian methylation array to profile 37,492 cytosine-guanine sites (CpGs) across highly conserved stretches of DNA in blood and skin samples (n = 171) from primarily three pinniped species representing the three phylogenetic families: Otariidae, Phocidae and Odobenidae. We built an elastic net model with Leave-One-Out-Cross Validation (LOOCV) and one with a Leave-One-Species-Out-Cross-Validation (LOSOCV). After identifying the top 30 CpGs, the LOOCV produced a highly correlated (r = 0.95) and accurate (median absolute error = 1.7 years) age estimation clock. The LOSOCV elastic net results indicated that blood and skin clock (r = 0.84) and blood (r = 0.88) pinniped clocks could predict age of animals from pinniped species not used for clock development to within 3.6 and 4.4 years, respectively. These epigenetic clocks provide an improved and relatively non-invasive tool to determine age in skin or blood samples from all pinniped species.

Highly pathogenic influenza A virus (HPIAV) H5N1 within the genetic clade 2.3.4.4b has emerged in wild birds in different regions of the world, leading to the death of >70 million birds. When these strains spread to pinniped species a remarkable mortality has also been observed. A detailed genetic characterization of HPIAV isolated from pinnipeds is essential to understand the potential spread of these viruses to other mammalian species, including humans. To gain insight into these matters a detailed phylogenetic analysis of HPIAV H5N1 2.3.4.4b strains isolated from pinniped species was performed. The results of these studies revealed multiple transmission events from birds to pinnipeds in all world regions. Different evolutionary histories of different genes of HPIAV H5N1 2.3.4.4b strains gave rise to the viruses infecting pinnipeds in different regions of the world. European strains isolated from pinnipeds represent a completely different genetic lineage from strains isolated from South American ones. All strains isolated from pinnipeds bear characteristics of a highly pathogenic form for of avian influenza in poultry. Amino acid substitutions, previously shown to confer an adaptive advantage for infecting mammals, were observed in different genes in all pinniped species studied.

From 2011-2018, we conducted surveillance in marine mammals along the California coast for influenza A virus (IAV), frequently detecting anti-influenza antibodies and intermittently detecting IAV. In spring 2019, this pattern changed. Despite no change in surveillance intensity, we detected IAV RNA in 10 samples in March and April, mostly in nasal and rectal swabs from northern elephant seals (Mirounga angustirostris). Although virus isolation was unsuccessful, IAV sequenced from one northern elephant seal nasal swab showed close genetic identity with pandemic H1N1 IAV subclade 6B.1A.1 that was concurrently circulating in humans in the 2018/19 influenza season. This represents the first report of human A(H1N1)pdm09 IAV in northern elephant seals since 2010, suggesting IAV continues to spill over from humans to pinnipeds.

The efficiency of quarry hydraulic excavators will depend on several factors, namely the climatic conditions of the area where hydraulic excavators are used, the degree of air pollution (pollination), the performance of the structural parts of the excavator, the reliability of the hydraulic system, the performance and cleanliness of the hydraulic working fluid. In this area, research was carried out on the performance of seals used in the hydraulic system of quarry excavators. The article presents the results of experimental tests of the existing type of oil seal a and b, as well as the proposed oil seal type c, shown in Fig. 1. [ABSTRACT FROM AUTHOR]

Under the Marine Mammal Protection Act of 1972, seals have recolonized historic ranges along the New England coast after near extirpation from bounty hunting in the 19th and 20th centuries. On Cape Cod, Massachusetts, concerns that rebounding seal populations damage fisheries and draw great white sharks have led some to call for a seal cull. Surveys on Cape Cod found strong opposition to lethal management among residents and tourists, and neutrality, on average, among commercial fishers. For all three samples, lethal management support was substantially explained by general attitudes toward seals and partially mediated by specific ecological benefits and risks associated with seals. Positive attitudes toward seals and perceived ecosystem benefits reduced support for lethal management among residents, tourists and commercial fishers. Negative attitudes and perceived ecological risks of seals increased lethal management support. These findings suggest communication of the ecological benefits of species can enhance continued marine mammal conservation. [ABSTRACT FROM AUTHOR]

This article deals with the question of the extent to which the Teutonic Order, as a clerical order of knights founded during the Third Crusade, succeeded in expressing its self-confidence and identity by means of its seal. The "geographical" area of investigation extends to the bailiwicks of Franconia, Alsace–Burgundy, Lorraine, Austria, An der Etsch and in the mountains (South Tyrol) as well as the so-called Deutschmeistertum, whereby the terms mentioned do not necessarily correspond to the present-day areas of that designation. The time frame is within the Middle Ages. Due to the large number of surviving seals of the Teutonic Order, however, only a small insight from a larger study can be provided here. Selected seals of the Order's various internal leadership strata are therefore presented, compared and examined to determine whether and to what extent they express a form of self-confidence and identity. [ABSTRACT FROM AUTHOR]

The in-pipe robot is the most commonly used technique in offshore pipelines. The use of rubber sealing discs is important for in-pipe robots to ensure that the robots are moved by fluid pressures inside offshore pipelines. This paper focuses on the measuring and modeling of the wax–oil gel-breaking process at the soft frictional area between sealing discs and the pipe wall. In this study, a detailed characterization of the gel-scraping process and in situ probing portable microscopy are performed. Two contributions are made in this study. First, a direct observation of wax–oil deposition breaking is employed to detect the minute changes at the in-pipe robot. Second, we find that a simple function is possible to describe the relationship between the wax contents and dewaxing efficiency, in which the debris material removal ratio (DRR) is discussed. Thus, the gel deposition-breaking phenomena are quite different under the influence of rubber sealing discs. This result is further confirmed by the real contact ratio measurements. It is important to research the sealing disc further and apply it more in the petroleum industry, especially in in-pipe robots for deepwater pipeline systems. [ABSTRACT FROM AUTHOR]

Social identity influences policy preferences and actions regarding wildlife. Using data from a survey of residents, commercial fishers, and tourists on Cape Cod, Massachusetts, this study examined the relationships between self-selected social identities (i.e., animal protection, environmental, hunter, and angler) within these stakeholder groups and ocean management priorities, support for the Marine Mammal Protection Act (MMPA), and acceptance of lethal management of seals and white sharks. Results revealed three social identity clusters: (1) identification with environmental and animal protection groups (non-consumptive), (2) identification with both non-consumptive (environmental, animal protection) and consumptive (angler, hunter) groups, and (3) identification with none of the groups. Residents were a mix of identities; tourists primarily identified with the non-consumptive and, to a lesser extent, no identification clusters; and commercial fishers identified with the mixed non-consumptive/consumptive and no identification clusters. The overlap between consumptive and non-consumptive identifications illustrates the heterogeneity of social identity. Participants in the non-consumptive cluster favored policies prioritizing wildlife, the environment, and marine mammal protections more strongly than those in other clusters. Findings contribute to research examining social identity theory to improve understanding of public wildlife management preferences, within the novel context of rebounding populations of marine predators such as pinnipeds and white sharks.

The resurgence of pinniped populations along the West Coast of the United States, a consequence of the Marine Mammal Protection Act, has resulted in unintended ecological and socio-economic repercussions. The conflict between pinniped and fisheries in California, a persistent management challenge for decades, primarily manifests as depredation (the removal or damage of hooked fish) from Commercial Passenger Fishing Vessels (CPFVs). Depredation not only results in stolen fish but also in lost fishing opportunities due to the presence of pinnipeds deterring target fish species or necessitating vessel relocation. Using logbook data from 1994 to 2021, we explored spatiotemporal trends in pinniped depredation of CPFVs in California. Our model, which evaluates the factors predicting the number of fish depredated, revealed a distinct concentration of pinniped depredation in Southern California, with increasing rates of depredation during summer and spring. Over our time series, depredation is decreasing, as our model found a seven percent decrease in the number of fish depredated each calendar year. Correspondingly, changepoint and trend analysis revealed two key trend reversals in 1999 and 2014, exemplified by a rapid peak and ensuing drop in overall depredation. Overall, our study suggests that depredation is shaped by an interplay of environmental factors, the population dynamics of pinnipeds, and the patterns of fishing activities within the California current ecosystem.

The darkness of the deep ocean limits the vision of diving predators, except when prey emit bioluminescence. It is hypothesized that deep-diving seals rely on highly developed whiskers to locate their prey. However, if and how seals use their whiskers while foraging in natural conditions remains unknown. We used animal-borne tags to show that free-ranging elephant seals use their whiskers for hydrodynamic prey sensing. Small, cheek-mounted video loggers documented seals actively protracting their whiskers in front of their mouths with rhythmic whisker movement, like terrestrial mammals exploring their environment. Seals focused their sensing effort at deep foraging depths, performing prolonged whisker protraction to detect, pursue, and capture prey. Feeding-event recorders with light sensors demonstrated that bioluminescence contributed to only about 20% of overall foraging success, confirming that whiskers play the primary role in sensing prey. Accordingly, visual prey detection complemented and enhanced prey capture. The whiskers' role highlights an evolutionary alternative to echolocation for adapting to the extreme dark of the deep ocean environment, revealing how sensory abilities shape foraging niche segregation in deep-diving mammals. Mammals typically have mobile facial whiskers, and our study reveals the significant function of whiskers in the natural foraging behavior of a marine predator. We demonstrate the importance of field-based sensory studies incorporating multimodality to better understand how multiple sensory systems are complementary in shaping the foraging success of predators.

Arctic states, regional and local authorities, NGOs, and Indigenous communities have debated how Arctic seals should be governed for more than a century. This governance discourse covers a wide array of issues, from seal hunting and the sale of animal products to the impacts of pollution and climate change. This article examines the frames used by political entities to discuss the regional governance of Arctic seals in the North American Arctic from 1900-2020, a period defined by landmark agreements on seals. Informed by framing and agenda-setting theory, the article employs textual analysis of policy documents and newspaper articles. These serve as a source of information and space for policy advocacy and debate to study political entities' discourse regarding the issues and policies that shape Arctic seal governance. The analysis focuses on English-language texts from regional and local newspapers and international newspapers of record. The article identifies four dominant frames, namely perceived threats to (a) economic revenue, (b) animal welfare, (c) Indigenous ways of life, and (d) threats emanating from the involvement of NGOs in Arctic regional governance. Each of these frames is associated with one or multiple political entities involved in the regional governance of seals. The article demonstrates how the dominance of these entities and the frames they employ varies over time and corresponds to several anthropogenic threats to seals, including commercial hunting, pollution, and climate change. The article concludes that tensions between local and regional entities and international and non-Arctic entities are reflective of broader Arctic regional governance dynamics. [ABSTRACT FROM AUTHOR]

The aim of this study was to describe the pathology in seals from which Listeria monocytogenes was isolated and investigate if the lesions' nature and severity were related to the phylogeny of isolates. L. monocytogenes was isolated from 13 of 50 (26%) dead grey seal (Halichoerus grypus) pups, six (12%) in systemic distribution, on the Isle of May, Scotland. Similar fatal L. monocytogenes -associated infections were found in a grey seal pup from Carnoustie, Scotland, and a juvenile harbour seal (Phoca vitulina) in the Netherlands. Whole genome sequencing of 15 of the L. monocytogenes isolates identified 13 multilocus sequence types belonging to the L. monocytogenes lineages I and II, but with scant phenotypic and genotypic antimicrobial resistance and limited variation in virulence factors. The phylogenetic diversity present suggests there are multiple sources of L. monocytogenes , even for seal pups born in the same colony and breeding season. This is the first description of L. monocytogenes isolated from, and detected in lesions in, pinnipeds and indicates that infection can be systemic and fatal. Therefore, listeriosis may be an emerging or overlooked disease in seals with infection originating from contamination of the marine environment. [ABSTRACT FROM AUTHOR]

The archaeological excavations at Oylum Höyük were started in 1987 by Prof. Dr. Engin Özgen. Since 2012, they have been carried out by Prof. Dr. Atilla Engin. During these excavations, a total of eight seals or seal impressions with Anatolian hieroglyphs were unearthed. This article will discuss a total of five seal or seal impressions that were found during excavations at Oylum Höyük near Kilis between 2011 and 2022. All examples are seals or seal impressions with Anatolian hieroglyphs, which give us information about the names or titles of the respective owners. So far, only a few written artefacts from the second half of the second millennium BC have been found in Oylum Höyük. However, these new finds should prove that considerably more finds are to be expected and that Oylum Höyük played an important role for the Hittites in northern Syria. [ABSTRACT FROM AUTHOR]

BOLOM-KOTARI, Martina. The Development of Seals of the Middle and Lower Clergy in Bohemia and Moravia in the Middle Ages. Basic Overview and Typology. The study focuses on the seals of the middle and lower clergy in Bohemia and Moravia in the Middle Ages. In contrast to the seals of bishops and archbishops, the sphragistic material of, for example, important episcopal officials, officials and vicars general, but also superiors and members of chapters, monastery superiors and priests, has received less attention in the form of partial studies that do not systematically cover the topic. The text provides basic information about the first appearance of seals of the mentioned ecclesiastical dignitaries. It focuses on the motifs they chose for their seals, the reasons for their use and their significance. The iconography of their seals was very varied; one can encounter portrait, hagiographic motifs and their combinations, as well as armorial, inscriptional and topographical motifs. The study also briefly summarizes the development of the use of coloured wax, the changes in the size of individual seals and notes the relationship between the size of seals of church dignitaries and other members of society. [ABSTRACT FROM AUTHOR]

The morphological and morphometric parameters of erythrocytes (size, shape, and color) were studied in five species of marine mammals. A comparative assessment of oxygen reserves in the blood of Harp seal (Pagophilus groenlandicus (Erxleben 1777)) and Grey seal (Halichoerus grypus (Fabricius 1791)) pups during adaptations to the aquatic environment, as well as of Bottlenose dolphins during the period of adaptation to conditions of captivity, is given. The morphometric parameters of red blood cells have been established to vary depending on the age, habitat conditions, and phylogenetic position of the animals. [ABSTRACT FROM AUTHOR]

Initiation of self-expanding high-temperature synthesis (SHS) in the Al–Ti–C system in the process of spark plasma sintering (SPS) of specimens allows obtaining a material with high density, which contains MAX-phases. A simple rheological theory has been developed, which can describe SHS and SPS processes under certain conditions. Within the framework of this model, the processes of pressing and extrusion at uniaxial pressure are considered. The dependence of the relative density of the powder mixture on time is scaled by the factor of the ratio of pressure to the viscosity of the invariant base of the material. Analytical time dependences of the plunger speed and sample height, as well as the time required to achieve the specified value of the relative density of the Al–Ti–C material, which allows us to predict and analyze the compression of powder mixtures in the SPS process were obtained. [ABSTRACT FROM AUTHOR]

An increase in the efficiency of gland seals in compressor cylinders with cast iron rings pressed against the contact surface of the piston rod using a steel spring in reciprocating compressors used in offshore oil and gas-condensate fields for gas-lift oil production systems is considered. Studies of a gas engine reciprocating compressor working directly on the operating gas-lift system have shown that in order to increase the time of normal operation of gland seals, it is necessary to adjust the clearance using lubricant up to 0.1 mm. After increasing the spring stiffness, the serviceability and number of working hours of the gland seal increased twofold, from 850 to 1700 h. [ABSTRACT FROM AUTHOR]

Understanding how marine animals behave around tidal turbines is essential if we are to quantify how individuals and populations may be affected by the installation of these devices in the coming decades. Our particular interest is in collision risk, and how this may be affected by the fine-scale behaviour of seals and small cetacean species around devices. We report on a study in which multibeam sonar data were collected close to an operational tidal turbine in Scotland continuously over a twelve-month period. The sonars provide high-resolution (a few cm) data over a 120° angle out to a range of 55 m at a rate of 10 frames per second. We describe a system which uses automatic computer algorithms to detect potential targets of interest, verified by human analysts using a sophisticated computer user interface to confirm detections and assign target species. To date, we have identified 359 tracks of marine mammals in the data, as well as several thousand tracks from fish and diving birds. These are currently being parameterised to study how these species react to the moving turbine rotors, and the data are now being used to explore the development of improved automated detection and classification algorithms. [ABSTRACT FROM AUTHOR]

Many marine animals migrate between foraging areas and reproductive sites, often timing the return migration with extreme precision. In theory, the decision to return should reflect energy acquisition at foraging areas, energetic costs associated with transit, and timing arrival for successful reproduction. For long-distance migrations to be successful, animals must integrate 'map' information to assess where they are relative to their reproductive site as well as 'calendar' information to know when to initiate the return migration given their distance from home1. Elephant seals, Mirounga angustirostris, migrate thousands of kilometers from reproductive sites to open ocean foraging areas (Figure 1A), yet return within a narrow window of time to specific beaches2. Each year, pregnant female elephant seals undertake a ∼240-day, 10,000 km foraging migration across the Northeast Pacific Ocean before returning to their breeding beaches, where they give birth 5 days after arriving2. We found that the seals' abilities to adjust the timing of their return migration is based on the perception of space and time, which further elucidates the mechanisms behind their astonishing navigational feats3.

Recently, the Institute for Radiological protection and Nuclear Safety (IRSN) has launched VSEAL (Vertical SEALing) project to investigate the impact of gas migration on the long-term performance of bentonite based vertical sealing systems (VSS). The first VSEAL in situ test was emplaced in IRSN's Underground Research Laboratory (URL) in Tournemire (France) in 2019 and was equipped with 76 wired and wireless sensors. The test is still in progress, but the collected set of data provides already valuable information of the hydro-mechanical behavior of VSS during hydration. The swelling core consists of a mixture of high-density pellets and powder of MX80 bentonite in a ratio of 80/20 (in dry mass). An innovative method was adopted to drill a 1-m diameter and ∼10-m deep shaft in order to minimize the rock perturbation at the sidewalls. Because a specific protocol was adopted to install the bentonite mixture together with a careful characterization of the core during construction, VSEAL 1 constitutes the unique in situ sealing test with a well-known initial structural distribution of the pellets and the powder. Some heterogeneities occurred within the experiment during the installation process: a damaged zone developed around the shaft walls due to the interruption of the installation operations caused by COVID19 lockdown in France; a technological gap with a variable thickness between the last pellets layer and the top confining lid and a heterogeneous distribution of the bentonite powder at some layers inducing large inter pellets voids close to the bentonite-rock interface. Artificially injected water volume, relative humidity, water content and swelling pressure in both radial and axial directions were monitored. Comparison of the results showed that the presence of installation-induced heterogeneities led to the generation of preferential flow paths that influenced the swelling pressure evolution at radial and axial directions.

During 2014–2019, the prevalence of Corynosoma spp., a parasite species in great cormorants (Phalacrocorax carbo spp.) and in Baltic herring (Clupea harengus membras), was studied in the Archipelago and the Bothnian Seas of the northern Baltic Sea. These results suggest that cormorants may act as a definitive host for these acanthocephalan parasites. Adults were more infected with the parasites than juveniles, which could be due to their larger size. A lower prevalence of Corynosoma spp. in juveniles may be because smaller cormorants eat smaller fish that have less parasites. We found that the most abundant corynosoma species in both the Baltic herring and cormorants were Corynosoma semerme, whereas only a few individuals of C. strumosum and only one C. magdaleni were found. The prevalence of corynosoma in herring increased from 2014 to 2018, and individuals in the Bothnian Sea were infected less frequently than herring in the Archipelago Sea. Results also showed that infected herring individuals were generally larger than non-infected individuals, which could be explained by their size and their feeding habits. Currently, the changing environment of the Baltic Sea may cause an effect on the herring making them more susceptible to infections. Our results, therefore, emphasize the importance of the regular monitoring of infections and the parasite-host relationships in the Baltic Sea.

This retrospective study used data obtained from medical records of 530 stranded free-ranging harbor (Phoca vitulina), grey (Halichoerus grypus), harp (Pagophilus groenlandicus), and hooded seals (Cystophora cristata) presented to the Marine Mammal Stranding Center in Brigantine, New Jersey from January 1998 through December 2016. The objective was to identify hematological and plasma biochemical parameters of seals at time of presentation that were associated with successful rehabilitation and with duration of hospitalization using univariate and multivariate logistic regressions. At presentation, animals that subsequently survived rehabilitation had greater alkaline phosphatase activity and absolute lymphocyte and total calcium concentrations and lower blood urea nitrogen, sodium, chloride, phosphorus, and total bilirubin concentrations and lower aspartate aminotransferase and alanine aminotransferase activities than animals that eventually died or were euthanized while under care. Results suggest that young, actively growing animals are more likely to survive rehabilitation and that bloodwork consistent with dehydration, systemic disease, and exhaustion are negative prognostic indicators. These results provide prognostic indicators that may aid clinical decision-making for seals presented for rehabilitation.

The Weddell seal (Leptonychotes weddellii) thrives in its extreme Antarctic environment. We generated the Weddell seal genome assembly and a high-quality annotation to investigate genome-wide evolutionary pressures that underlie its phenotype and to study genes implicated in hypoxia tolerance and a lipid-based metabolism. Genome-wide analyses included gene family expansion/contraction, positive selection, and diverged sequence (acceleration) compared to other placental mammals, identifying selection in coding and non-coding sequence in five pathways that may shape cardiovascular phenotype. Lipid metabolism as well as hypoxia genes contained more accelerated regions in the Weddell seal compared to genomic background. Top-significant genes were SUMO2 and EP300; both regulate hypoxia inducible factor signaling. Liver expression of four genes with the strongest acceleration signals differ between Weddell seals and a terrestrial mammal, sheep. We also report a high-density lipoprotein-like particle in Weddell seal serum not present in other mammals, including the shallow-diving harbor seal.

Our aim was to develop a method for estimating the number of animals using a single site in an asynchronous species, meaning that not all animals are present at once so that no one count captures the entire population. This is a common problem in seasonal breeders, and in northern elephant seals, we have a model for quantifying asynchrony at the Año Nuevo colony. Here we test the model at several additional colonies having many years of observations and demonstrate how it can account for animals not present on any one day. This leads to correction factors that yield total population from any single count throughout a season. At seven colonies in California for which we had many years of counts of northern elephant seals, we found that female arrival date varied < 2 days between years within sites and by < 5 days between sites. As a result, the correction factor for any one day was consistent, and at each colony, multiplying a female count between 26 and 30 Jan by 1.15 yielded an estimate of total population size that minimized error. This provides a method for estimating the female population size at colonies not yet studied. Our method can produce population estimates with minimal expenditure of time and resources and will be applicable to many seasonal species with asynchronous breeding phenology, particularly colonial birds and other pinnipeds. In elephant seals, it will facilitate monitoring the population over its entire range.

Bonding between mothers and their young is fundamental to mammalian reproductive behaviour and individual fitness. In social systems where the risk of confusing filial and non-filial offspring is high, mothers should demonstrate early, strong and consistent responses to their kin throughout the period of offspring dependence, irrespective of maternal traits. We tested this hypothesis through playback experiments in the northern elephant seal Mirounga angustirostris, a phocid species that breeds in high-density colonies. We found that mothers recognized their offspring throughout lactation and as early as 1-2 days after parturition. Measures of experience (age) and temperament (aggressivity) did not predict their response strength to filial playback treatments, nor did pup age or sex. Some mothers showed great consistency in behavioural responses throughout the lactation period, while others were less predictable. The strength of a female's response did not influence her pup's weaning weight; however, more consistent females weaned pups of higher mass. This is a rare demonstration of individual recognition among phocid mothers and their offspring, and suggests that consistency in maternal responsiveness may be an important social factor influencing the pup's growth and survival.

Understanding the tribological behavior of elastomers in dry conditions is essential for sealing applications, as dry contact may occur even in lubricated conditions due to local dewetting. In recent decades, Persson and co-authors have developed a comprehensive theory for rubber contact mechanics and dry friction. In this work, their model is implemented and extended, particularly by including static friction based on the bond population model by Juvekar and coworkers. Validation experiments are performed using a tribometer over a wide range of materials, temperatures and speeds. It is shown that the friction model presented in this work can predict the static and dynamic dry friction of various commercial rubber materials with different base polymers (FKM, EPDM and NBR) with an average accuracy of 10%. The model is then used to study the relevance of different elastomer friction contributions under various operating conditions and for different roughness of the counter surface. The present model will help in the development of novel optimized sealing solutions and provide a foundation for future modeling of lubricated elastomer friction.