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The prolonged, postweaning fast of northern elephant seal (Mirounga angustirostris) pups is characterized by a reliance on lipid metabolism and reversible, fasting-induced insulin resistance, providing a unique model to examine the effects of insulin on lipid metabolism. We have previously shown that acute insulin infusion induced a shift in fatty acid metabolism dependent on fasting duration. This study complements the previous study by examining the effects of fasting duration and insulin infusion on circulating levels of oxylipins, bioactive metabolites derived from the oxygenation of polyunsaturated fatty acids. Northern elephant seal pups were studied at two postweaning periods (n = 5/period): early fasting (1-2 wk postweaning; 127 ± 1 kg) and late fasting (6-7 wk postweaning; 93 ± 4 kg). Different cohorts of pups were weighed, sedated, and infused with 65 mU/kg of insulin. Plasma was collected prior to infusion (T0) and at 10, 30, 60, and 120 min postinfusion. A profile of ∼80 oxylipins was analyzed by UPLC-ESI-MS/MS. Nine oxylipins changed between early and late fasting and eight were altered in response to insulin infusion. Fasting decreased prostaglandin F2α (PGF2α) and increased 14,15-dihydroxyicosatrienoic acid (14,15-DiHETrE), 20-hydroxyeicosatetraenoic acid (20-HETE), and 4-hydroxy-docosahexaenoic acid (4-HDoHE) (P < 0.03) in T0 samples, whereas insulin infusion resulted in an inverse change in area-under-the-curve (AUC) levels in these same metabolites (P < 0.05). In addition, 12-12-hydroperoxyeicosatetraenoic acid (HpETE) and 12-HETE decreased with fasting and insulin infusion, respectively (P < 0.04). The oxylipins altered during fasting and in response to insulin infusion may contribute to the manifestation of insulin resistance and participate in the metabolic regulation of associated cellular processes.

All organisms face resource limitations that will ultimately restrict population growth, but the controlling mechanisms vary across ecosystems, taxa, and reproductive strategies. Using four decades of data, we examine how variation in the environment and population density affect reproductive outcomes in a capital-breeding carnivore, the northern elephant seal (Mirounga angustirostris). This species provides a unique opportunity to examine the relative importance of resource acquisition and density-dependence on breeding success. Capital breeders accrue resources over large temporal and spatial scales for use during an abbreviated reproductive period. This strategy may have evolved, in part, to confer resilience to short-term environmental variability. We observed density-dependent effects on weaning mass, and maternal age (experience) was more important than oceanographic conditions or maternal mass in determining offspring weaning mass. Together these findings show that the mechanisms controlling reproductive output are conserved across terrestrial and marine systems and vary with population dynamics, an important consideration when assessing the effect of extrinsic changes, such as climate change, on a population.

We detected a novel poxvirus from a gray seal (Halichoerus grypus) from the North Sea, Germany. The juvenile animal showed pox-like lesions and deteriorating overall health condition and was finally euthanized. Histology, electron microscopy, sequencing, and PCR confirmed a previously undescribed poxvirus of the Chordopoxvirinae subfamily, tentatively named Wadden Sea poxvirus.

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.

The publication of the charters of the Abbaye de Longpont in the twelfth century is important, since we know of around 200 acts received by this great monastery. But it is a complex task, given the almost total absence of originals, and the fact that only very partial cartularies exist. Fortunately, we have the copying and analysis work carried out by Gaignières: around a quarter of the acts are known to us only through him, which shows just how valuable his contribution is. However, rather than making full (and reliable!) copies, Gaignières favoured partial copies or analyses, depending on what interested him most: the names of families as well as the seals.

This article examines the involvement of Beatrice, dowager Baroness Roos (d. 1415) in the making of art. Her patronage of masons and tomb-makers, glaziers and seal-makers, is explored in detail, showing her to have commissioned works from two of the most prominent English artists of the late medieval period. Her interest in the inventive use of heraldry and her role in the creation of a major monument in St Paul's Cathedral is established. Her right to be acknowledged as the donor of the St William window in York Minster is reasserted, and her influence on its content and meaning is demonstrated. The gift of this window made Beatrice the single most important secular benefactor of York Minster, a fact that has not been acknowledged before in print, but was recorded by the medieval cathedral chapter in the glazing of the Minster's western choir clerestory. [ABSTRACT FROM AUTHOR]

Modular gas delivery systems replaced conventional gas panels in the semiconductor capital equipment industry for “dry” manufacturing processes. Modular gas delivery systems were adopted for many benefits over conventional system designs. These benefits include smaller size / footprint, easily customizable configurability, ease of maintenance, and increased equipment productivity. From our position as a gas panel supplier to major dry processing equipment manufacturers we have observed and responded to the customer-driven conversion to modular gas delivery systems. We present here details about the industry’s conversion from conventional to modular architecture and three areas of focus of development on the modular system architecture: serviceability, sealing mechanisms, and contamination control. In parallel to system-level work, the importance of component performance improvement shall not be neglected. From conventional to modular architecture, the use of mixer and mixing performance are critical in wafer manufacturing, yet it is often overlooked in equipment design and characterization. Among all component development and characterization, we would like to highlight our modular mixer development and testing work, including discussion on impact of mixer performance on wafer production processes, our modeling approach in mixer design, and test data for validation. [ABSTRACT FROM AUTHOR]

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. [Display omitted] • Corynosoma parasites in herring and cormorants were studied in northern Baltic Sea. • In 2014–2019, 7002 herrings and 65 cormorants were examined for parasites by PCR. • DNA analysis revealed three species: C. semerme , C. strumosum , and C. magdaleni. • In herring, Corynosoma infections increased between 2014 and 2018 (mean PR = 0.15). • Of cormorants, PR = 0.29 were infected by Corynosomas , represented only C. semerme. [ABSTRACT FROM AUTHOR]

To understand susceptibility of wild California sea lions and Northern elephant seals to influenza A virus (IAV), we developed an ex vivo respiratory explant model and used it to compare infection kinetics for multiple IAV subtypes. We first established the approach using explants from colonized rhesus macaques, a model for human IAV. Trachea, bronchi, and lungs from 11 California sea lions, 2 Northern elephant seals, and 10 rhesus macaques were inoculated within 24 h postmortem with 6 strains representing 4 IAV subtypes. Explants from the 3 species showed similar IAV infection kinetics, with peak viral titers 48 to 72 h post-inoculation that increased by 2 to 4 log10 PFU/explant relative to the inoculum. Immunohistochemistry localized IAV infection to apical epithelial cells. These results demonstrate that respiratory tissue explants from wild marine mammals support IAV infection. In the absence of the ability to perform experimental infections of marine mammals, this ex vivo culture of respiratory tissues mirrors the in vivo environment and serves as a tool to study IAV susceptibility, host range, and tissue tropism. IMPORTANCE Although influenza A virus can infect marine mammals, a dearth of marine mammal cell lines and ethical and logistical challenges prohibiting experimental infections of living marine mammals mean that little is known about IAV infection kinetics in these species. We circumvented these limitations by adapting a respiratory tract explant model first to establish the approach with rhesus macaques and then for use with explants from wild marine mammals euthanized for nonrespiratory medical conditions. We observed that multiple strains representing 4 IAV subtypes infected trachea, bronchi, and lungs of macaques and marine mammals with variable peak titers and kinetics. This ex vivo model can define infection dynamics for IAV in marine mammals. Further, use of explants from animals euthanized for other reasons reduces use of animals in research.

The auditory biology of Monachinae seals is poorly understood. Limited audiometric data and certain anatomical features suggest that these seals may have reduced sensitivity to airborne sounds compared to related species. Here, we describe the in-air hearing abilities of a Hawaiian monk seal (Neomonachus schauinslandi) trained to participate in a psychophysical paradigm. We report absolute (unmasked) thresholds for narrowband signals measured in quiet conditions across the range of hearing and masked thresholds measured in the presence of octave-band noise at two frequencies. The behavioral audiogram indicates a functional hearing range from 0.1 to 33 kHz and poor sensitivity, with detection thresholds above 40 dB re 20 µPa. Critical ratio measurements are elevated compared to those of other seals. The apparently reduced terrestrial hearing ability of this individual-considered with available auditory data for a northern elephant seal (Mirounga angustirostris)-suggests that hearing in Monachinae seals differs from that of the highly sensitive Phocinae seals. Exploration of phylogenetic relationships and anatomical traits support this claim. This work advances understanding of the evolution of hearing in amphibious marine mammals and provides updated information that can be used for management and conservation of endangered Hawaiian monk seals.

The postweaning fast of northern elephant seal pups is characterized by a lipid-dependent metabolism and associated with a decrease in plasma glucagon-like peptide-1 (GLP-1), insulin, and glucose and increased gluconeogenesis (GNG) and ketogenesis. We have also demonstrated that exogenous GLP-1 infusion increased plasma insulin despite simultaneous increases in cortisol and glucagon, which collectively present contradictory regulatory stimuli of GNG, ketogenesis, and glycolysis. To assess the effects of GLP-1 on metabolism using primary carbon metabolite profiles in late-fasted seal pups, we dose-dependently infused late-fasted seals with low (LDG; 10 pM/kg; n = 3) or high (HDG; 100 pM/kg; n = 4) GLP-1 immediately following a glucose bolus (0.5 g/kg), using glucose without GLP-1 as control (n = 5). Infusions were performed in similarly aged animals 6-8 wk into their postweaning fast. The plasma metabolome was measured from samples collected at five time points just prior to and during the infusions, and network maps constructed to robustly evaluate the effects of GLP-1 on primary carbon metabolism. HDG increased key tricarboxylic acid (TCA) cycle metabolites, and decreased phosphoenolpyruvate and acetoacetate (P < 0.05) suggesting that elevated levels of GLP-1 promote glycolysis and suppress GNG and ketogenesis, which collectively increase glucose clearance. These GLP-1-mediated effects on cellular metabolism help to explain why plasma GLP-1 concentrations decrease naturally in fasting pups as an evolved mechanism to help conserve glucose during the late-fasting period.

Seasonal resource pulses can have enormous impacts on species interactions. In marine ecosystems, air-breathing predators often drive their prey to deeper waters. However, it is unclear how ephemeral resource pulses such as near-surface phytoplankton blooms alter the vertical trade-off between predation avoidance and resource availability in consumers, and how these changes cascade to the diving behaviour of top predators. We integrated data on Weddell seal diving behaviour, diet stable isotopes, feeding success and mass gain to examine shifts in vertical foraging throughout ice break-out and the resulting phytoplankton bloom each year. We also tested hypotheses about the likely location of phytoplankton bloom origination (advected or produced in situ where seals foraged) based on sea ice break-out phenology and advection rates from several locations within 150 km of the seal colony. In early summer, seals foraged at deeper depths resulting in lower feeding rates and mass gain. As sea ice extent decreased throughout the summer, seals foraged at shallower depths and benefited from more efficient energy intake. Changes in diving depth were not due to seasonal shifts in seal diets or horizontal space use and instead may reflect a change in the vertical distribution of prey. Correspondence between the timing of seal shallowing and the resource pulse was variable from year to year and could not be readily explained by our existing understanding of the ocean and ice dynamics. Phytoplankton advection occurred faster than ice break-out, and seal dive shallowing occurred substantially earlier than local break-out. While there remains much to be learned about the marine ecosystem, it appears that an increase in prey abundance and accessibility via shallower distributions during the resource pulse could synchronize life-history phenology across trophic levels in this high-latitude ecosystem.

Like landscapes of fear, animals are hypothesized to strategically use lightscapes based on intrinsic motivations. However, longitudinal evidence of state-dependent risk aversion has been difficult to obtain in wild animals. Using high-resolution biologgers, we continuously measured body condition, time partitioning, three-dimensional movement, and risk exposure of 71 elephant seals throughout their 7-month foraging migrations (N = 16,000 seal days). As body condition improved from 21 to 32% fat and daylength declined from 16 to 10 hours, seals rested progressively earlier with respect to sunrise, sacrificing valuable nocturnal foraging hours to rest in the safety of darkness. Seals in superior body condition prioritized safety over energy conservation by resting >100 meters deeper where it was 300× darker. Together, these results provide empirical evidence that marine mammals actively use the three-dimensional lightscape to optimize risk-reward trade-offs based on ecological and physiological factors.

The article discusses the main methods for calculating seals of hybrid power machines. The analysis of works on the designs of hybrid power machines is carried out. The main types of piston seals of pumps, compressors and hybrid power machines are considered, with an emphasis on the main advantages and disadvantages of each type of seal, as well as recommendations on the choice of seals for hybrid power machines. Based on the analysis of the work on the research of piston seals, the main methods for calculating the seals of hybrid power machines are considered and the most suitable one is determined.

Phenological shifts are among the most obvious biological responses to environmental change, yet documented responses for Southern Ocean marine mammals are extremely rare. Marine mammals can respond to environmental changes through phenological flexibility of their life-history events such as breeding and moulting. Southern elephant seals (Mirounga leonina) undergo an obligatory annual moult which involves the rapid shedding of epidermal skin and hair while seals fast ashore. We quantified the timing (phenology) and duration (the time from arrival ashore to departure) of the moult haulout of 4612 female elephant seals at Marion Island over 32 years. Using linear mixed-effects models, we investigated age, breeding state and environmental drivers of moult timing and haulout duration. We found no clear evidence for a temporal shift in moult phenology or its duration. Annual variation in moult arrival date and haulout duration was small relative to age and breeding effects, which explained more than 90% of the variance in moult arrival date and 25% in moult haulout duration. All environmental covariates we tested explained minimal variation in the data. Female elephant seals moulted progressively later as juveniles, but adults age 4 and older had similar moult start dates that depended on the breeding state of the female. In contrast, moult haulout duration was not constant with age among adults, but instead became shorter with increasing age. Moulting is energetically expensive and differences in the moult haulout duration are possibly due to individual variation in body mass and associated metabolizable energy reserves, although other drivers (e.g. hormones) may also be present. Individual-based data on moult arrival dates and haulout duration can be used as auxiliary data in demographic modelling and may be useful proxies of other important biological parameters such as body condition and breeding history.

BackgroundResolving the preferred prey items and dietary proportions of leopard seals is central to understanding food-web dynamics in the rapidly-warming Antarctic Peninsula region. Previous studies have identified a wide range of prey items; however, due to anecdotal or otherwise limited information, leopard seal diets remain unresolved by seal sex, individual, body size, region, and season. Over the 2013, 2014, and 2017 field seasons we collected scat, tissue samples (red blood cells and plasma; n = 23) for stable isotope analyses, and previously-reported animal-borne video from 19 adult leopard seals foraging near mesopredator breeding colonies at Cape Shirreff, Livingston Island. We summarized a priori diet information from scat and video analysis and applied a three-isotope (δ13C, δ15N, δ34S), four-source (fish, fur seal, krill, penguin) Bayesian mixing model to examine temporal variability in both prey sources and leopard seal tissues.ResultsThe austral spring diets of males and females focused on Antarctic krill (31.7-38.0%), notothen fish (31.6-36.5%), and penguin (24.4-26.9%) and were consistent across all 3 years. Several lines of evidence suggest the transition to summer foraging was distinct for males and females. Female diets transitioned rapidly to higher δ15N values (+2.1‰), indicating increased consumption of penguin (29.5-46.2%) and energy-dense Antarctic fur seal pup (21.3-37.6%).ConclusionsThe seasonal increase in leopard seal δ15N values, and thus fur seal in their diet, was predictably related to larger body size; it may also be forcing reductions to the largest Antarctic fur seal colony in the Antarctic Peninsula. Our ensemble sampling approach reduces historical biases in monitoring marine apex predator diets. Further, our results are necessary to best inform regional fisheries management planning.

Key improvements are needed for implementation of the Endangered Species Act

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.

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.

The beginning of the Armenian printed book is a new era for Armenian writing and literature. It has completely inherited all the traditions of manuscripts. Remember that throughout the sixteenth and nineteenth centuries, printed and handwritten literature coexisted and served the public. Ancient books, like manuscripts, have handwritten remarks by historical masters, library inventory numbers, and other different kinds of notes in the margins, on free pages. Seals hold equal significance to these. In addition to being a unique source for printing, the compilation of handwritten and library notes found in the National Library's ancient books is also an excellent source for research on history in general, and culture history in particular. [ABSTRACT FROM AUTHOR]

Due to the limited battery and computing resource, offloading unmanned aerial vehicles (UAVs)’ computation tasks to ground infrastructure, e.g., vehicles, is a fundamental framework. Under such an open and untrusted environment, vehicles are reluctant to share their computing resource unless provisioning strong incentives, privacy protection, and fairness guarantee. Precisely, without strategy-proofness guarantee, the strategic vehicles can overclaim participation costs so as to conduct market manipulation. Without the fairness provision, vehicles can deliberately abort the assigned tasks without any punishments, and UAVs can refuse to pay by the end, causing an exchange dilemma. Lastly, the strategy-proofness and fairness provision typically require transparent payment/task results exchange under public audit, which may disclose sensitive information of vehicles and make the privacy preservation a foremost issue. To achieve the three design goals, we propose SEAL, an integrated framework to address Strategy-proof, fair, and privacy-prEserving UAV computation offLoading. SEAL deploys a strategy-proof reverse combinatorial auction mechanism to optimize UAVs’ task offloading under practical constraints while ensuring economic-robustness and polynomial-time efficiency. Based on smart contracts and hashchain micropayment, SEAL implements a fair on-chain exchange protocol to realize the atomic completion of batch payments and computing results in multi-round auctions. In addition, a privacy-preserving off-chain auction protocol is devised with the assistance of the trusted processor to efficiently protect vehicles’ bid privacy. Using rigorous theoretical analysis and extensive simulations, we validate that SEAL can effectively prevent vehicles from manipulating, ensure privacy protection and fairness, improve the offloading efficiency, and reduce UAV’s energy costs and expenses with low overheads. [ABSTRACT FROM AUTHOR]

The impacts of climate change on the health of marine mammals are increasingly being recognised. Given the rapid rate of environmental change in the Arctic, the potential ramifications on the health of marine mammals in this region are a particular concern. There are eleven endemic Arctic marine mammal species (AMMs) comprising three cetaceans, seven pinnipeds, and the polar bear (Ursus maritimus). All of these species are dependent on sea ice for survival, particularly those requiring ice for breeding. As air and water temperatures increase, additional species previously non-resident in Arctic waters are extending their ranges northward, leading to greater species overlaps and a concomitant increased risk of disease transmission. In this study, we review the literature documenting disease presence in Arctic marine mammals to understand the current causes of morbidity and mortality in these species and forecast future disease issues. Our review highlights potential pathogen occurrence in a changing Arctic environment, discussing surveillance methods for 35 specific pathogens, identifying risk factors associated with these diseases, as well as making recommendations for future monitoring for emerging pathogens. Several of the pathogens discussed have the potential to cause unusual mortality events in AMMs. Brucella, morbillivirus, influenza A virus, and Toxoplasma gondii are all of concern, particularly with the relative naivety of the immune systems of endemic Arctic species. There is a clear need for increased surveillance to understand baseline disease levels and address the gravity of the predicted impacts of climate change on marine mammal species. [ABSTRACT FROM AUTHOR]

Wildlife research in the polar regions has historically been limited by the logistical constraints of site access, but recent developments in the use of satellite imagery for animal detection has unlocked new possibilities for pan-Arctic and pan-Antarctic monitoring of animal populations. A range of different sensor systems have been used for wildlife research, but most have focused on optical sensors that collect data in the visible spectrum and can be directly interpreted similar to a photograph. These include medium-resolution sensors like Landsat (30 m) and Sentinel-2 (10 m) and very high-resolution sensors such as Maxar’s Worldview-2 (51 cm) and Worldview-3 (31 cm). These long-established satellite systems have been joined more recently by constellations of smaller satellites (so-called “Small Sats”) that offer imagery of comparable spatial and spectral resolution to those operated by Maxar. This rapidly expanding portfolio of earth observation satellites offers the potential for a radical transformation of wildlife research in polar regions, but the sheer volume of data being collected now eclipses our capacity for manual imagery interpretation. To meet this challenge, researchers are now harnessing advances in computer vision that, coupled with improvements in computing capacity, promise to deliver a new era in our ability to monitor polar wildlife. [ABSTRACT FROM AUTHOR]

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To study the effect of soft segments of thermoplastic polyurethane elastomer (TPU) material on the sealing performance of hydraulic cylinders, a series of TPU materials were synthesized by polybutylene adipate diol (PBA),polycarbonate diol (PCDL), polycaprolactone diol(PCL), polytetrahydrofuran ether diol ( PTMEG ), diphenyl methane-4, 4'--diisocyanate (MDI) and hydroquinone dihydroxyethyl ether (HQEE).The effects of soft segment types on physical and mechanical properties, friction and wear properties, hydraulic oil aging properties and sealing properties of TPU materials were studied. The results show that the four kinds of TPU materials synthesized by four soft segments have good physical and mechanical properties. PBA-type TPU material has the best wear resistance, and the friction coefficient of the TPU materials synthesized by four soft segments under the condition of hydraulic oil lubrication is 0. 05, indicating a lower friction coefficient. PCDL--type TPU material has the best tolerance to hydraulic oil and sealing performance. PCDL--type TPU material is an ideal material for manufacturing hydraulic cylinder seals. [ABSTRACT FROM AUTHOR]

One of the most remarkable features of the language of early Greek writing is a pervasive rhetorical strategy which consists in personifying objects for the purpose of identifying humans closely associated with them. Such 'speaking objects' have no Semitic parallel; how, then, is their conventional status in the Archaic Age to be explained? This article first considers the formulaic language of speaking objects, which is no straightforward transcription of speech, and seeks to explain where it comes from. It then turns to the question of why writers employed the curious strategy of personification by setting it in the broader context of early Greek writing and literature. Variously analogous to herms, slaves and skytalai , speaking objects are shown to have been conceived as messengers acting on behalf of their senders by not speaking in their name. [ABSTRACT FROM AUTHOR]

Late Bronze Age seals and sealings from Aegean Anatolia (the western part of western Anatolia) are a very heterogeneous collection of finds. Especially widespread are seals belonging to the Aegean tradition, including earlier hard stone seals and later soÁ stone lentoids related to the Mycenaean Mainland Popular Group. Also represented are seals executed in the central Anatolian style, which, however, arrive later to the area of study. In both groups, imports as well as local production are aested, and some seals show individual features. e spread of these objects is related to various factors, such as commercial and cultural exchange, but also political and military impacts. Participation in long-distance trade networks is confirmed by the presence of seals coming from the eastern Mediterranean.

A document containing unique information about the seals on medieval acts that were stored in the early 18th century in the archives of the “Moscow” (i. e. Kremlin) monasteries is examined and published in the article. It has been established that this description was compiled by the Monastyrskii Prikaz in 1709 in response to the request of Tsar Peter I and was attached to the letter of I. A. Musin-Pushkin, the Prikaz’s Head. The document was not found and was considered lost, when the Letters and Papers of Emperor Peter the Great were published in 1709. The description contains information about official seals from the archives of two of the four Kremlin monasteries that existed that time — Chudov and Afanasievsky (the courtyard of the Kirillo-Belozersky monastery). Four seals were discovered, described and drawn in the Chudov archive, and one in the Afanasevsky archive. The author considers the description as the origins of scientific sphragistics, since the compilation of this document is clearly out of the scope of practical tasks (identification of the act in the monastic archive and indication of its proper certification).

Baikal seals (Pusa sibirica) are a unique freshwater pinniped that inhabits Lake Baikal in the interior of Eastern Siberia. These seals were critical resources for human groups living along the lake through at least the Holocene. This study develops osteometric methods for assessing Baikal seal body size, including body mass and nose-tail length. This was accomplished through the analysis of biometric and osteometric data for 354 modern Baikal seals. The resulting methods can be expediently used to estimate seal body mass and length. Using these methods, we explore seal use at Sagan-Zaba II, a habitation site on Lake Baikal with deposits spanning much of the past 9000 years. These analyses reveal a general preference for smaller-bodied seals, particularly during the Middle Holocene, and a paucity of larger individuals in the assemblage. Previous ageing of seal remains from Sagan-Zaba II based on incremental structures in seal canines suggested a very similar pattern of seal use. These methods provide useful insights on seal use that complement those already developed for estimating seal age and season of death. [ABSTRACT FROM AUTHOR]

The identification of discrete intraspecific units, such as genetically informed management units (MUs), is important to effectively develop and implement conservation strategies for protected species. Harbour seals (Phoca vitulina) occurring in Irish waters are currently viewed as a single nationwide panmictic population (and hence MU), although this assumption is not based on any knowledge of population structure because of the lack of available genetic data.Thus, the present study used mitochondrial control region sequences and between nine and 11 microsatellite loci from harbour seals from Ireland and Northern Ireland (up to n = 123) and adjacent UK/European waters (up to n = 289) to provide insights into the genetic population structure and diversity of harbour seals in the areas studied.Within the island of Ireland, genetic analyses revealed the presence of three genetically distinct local populations, characterized by high genetic diversity, hereby defined as: East Ireland (EI), North‐west & Northern Ireland (NWNI), and South‐west Ireland (SWI).Using previously published and newly generated data, a subsequent wider scale analysis revealed that the EI and SWI local populations were genetically distinct from neighbouring UK/European areas, whereas seals from the NWNI area could not be distinguished from a previously identified Northern UK metapopulation. Migration rate estimates showed that NWNI receives migrants from North‐west Scotland, with NWNI acting as a genetic source for both SWI and EI.The present study provides the most comprehensive genetic assessment of harbour seals in European waters to date, with findings indicating that conservation strategies for harbour seals in Irish waters should be amended to accommodate at least three genetically distinct local populations/MUs. The use of approaches considering both ecological and genetic parameters is recommended for future assessments and delineation of units of ecological relevance for conservation management purposes. [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.

Animals can respond to dynamic environments through phenological plasticity of life history events; however, changes in one part of the annual cycle can diminish the success of subsequent life history events. Our aims were to determine the associations between reproduction and moult phenology across years and to quantify phenological plasticity across varying environmental conditions. We conducted demographic surveys of 4,252 flipper-tagged Weddell seals (Leptonychotes weddellii) in the Ross Sea, Antarctica during four austral summers. At each sighting, seals were assigned a moult code based on the visible presence of new fur and the start date of each animal's moult was back-calculated. Reproductive success and parturition dates were obtained for the breeding season prior to and following the moult. We found that successful reproduction delayed moult by 16 days relative to non-parturient females. Phenology of the intervening moult was indicative of previous reproductive dynamics but not predictive of subsequent reproductive outcomes. Across years, moult phenology varied by about two weeks and covaried strongly with sea ice break-out timing for all reproductive categories. Our findings suggest these polar mammals have some flexibility within the annual cycle that allows adjustment of moult phenology to fluctuating environmental conditions without compromising future reproductive success.

Vocal dialects are fundamental to our understanding of the transmission of social behaviours between individuals and populations, however few accounts trace this phenomenon among mammals over time. Northern elephant seals (Mirounga angustirostris) provide a rare opportunity to examine the trajectory of dialects in a long-lived mammalian species. Dialects were first documented in the temporal patterns of the stereotyped vocal displays produced by breeding males at four sites in the North Pacific in 1968 and 1969, as the population recovered from extreme exploitation. We evaluated the longevity of these geographical differences by comparing these early recordings to calls recently recorded at these same locations. While the presence of vocal dialects in the original recordings was re-confirmed, geographical differences in vocal behaviour were not found at these breeding rookeries nearly 50 years later. Moreover, the calls of contemporary males displayed more structural complexity after approximately four generations, with substantial between-individual variation and call features not present in the historical data. In the absence of measurable genetic variation in this species-owing to an extreme population bottleneck-a combination of migration patterns and cultural mutation are proposed as factors influencing the fall of dialects and the dramatic increase in call diversity.

Simple Summary: Plastic pollution is spreading worldwide and a growing number of reports point to the presence of plastic waste and microplastics in Antarctic marine ecosystems. Although the available data do not yet allow us to define the distribution of microplastics in the biotic and abiotic components of the Southern Ocean, in discussing the possible interactions with other contaminants in wastewater from scientific stations and their possible combined effects on primary producers and food webs, this review emphasizes the urgent need for standardized protocols of sampling and analysis of microplastics. Considering the unique oceanographic and biological characteristics of the Southern Ocean, we also suggest evaluating the likely cumulative stresses in Antarctic marine organisms and ecosystems due to exposure to climate-induced environmental changes, such as the recent decrease in sea-ice formation and seawater acidification. Antarctica and the Southern Ocean are the most remote regions on Earth, and their quite pristine environmental conditions are increasingly threatened by local scientific, tourism and fishing activities and long-range transport of persistent anthropogenic contaminants from lower latitudes. Plastic debris has become one of the most pervasive and ubiquitous synthetic wastes in the global environment, and even at some coastal Antarctic sites it is the most common and enduring evidence of past and recent human activities. Despite the growing scientific interest in the occurrence of microplastics (MPs) in the Antarctic environment, the lack of standardized methodologies for the collection, analysis and assessment of sample contamination in the field and in the lab does not allow us to establish their bioavailability and potential impact. Overall, most of the Southern Ocean appears to be little-affected by plastic contamination, with the exception of some coastal marine ecosystems impacted by wastewater from scientific stations and tourist vessels or by local fishing activities. Microplastics have been detected in sediments, benthic organisms, Antarctic krill and fish, but there is no clear evidence of their transfer to seabirds and marine mammals. Therefore, we suggest directing future research towards standardization of methodologies, focusing attention on nanoplastics (which probably represent the greatest biological risks) and considering the interactions of MPs with macro- and microalgae (especially sea-ice algae) and the formation of epiplastic communities. In coastal ecosystems directly impacted by human activities, the combined exposure to paint chips, metals, persistent organic pollutants (POPs), contaminants of emerging interest (CEI) and pathogenic microorganisms represents a potential danger for marine organisms. Moreover, the Southern Ocean is very sensitive to water acidification and has shown a remarkable decrease in sea-ice formation in recent years. These climate-related stresses could reduce the resilience of Antarctic marine organisms, increasing the impact of anthropogenic contaminants and pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

This paper is intended as the first of a series of studies aimed at a reclassification and re-evaluation of Urartian glyptic. In this specific contribution we have chosen to firstly analyse exclusively that group of seal impressions that have short cuneiform inscriptions attributable to the royal and palatine sphere of Urartu. [ABSTRACT FROM AUTHOR]

Roman gems have continued to be discovered in Roman Britain and published in archaeological reports and notes since the author completed his Corpus of Gems from British Sites in 1978. A new source of glyptic material can be found in the on-line publication of Portable Antiquities (Portable Antiquities Scheme) which includes intaglios, most of them found without stratigraphical context, by users of metal detectors, though many are set in rings, which provide significant aids in dating. Others were clearly re-used as they are set in seal matrices or medieval rings and were frequently freshly imported at that period from southern Europe. In the High Middle Ages, as in Roman times, intaglios reflect the interests, and patterns of thought of those who wore and valued these beautiful objects. [ABSTRACT FROM AUTHOR]

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The research commenced with the synthesis of antimony-impregnated graphite composites, designated as C/Sb20 %, incorporating 20 % by weight of antimony. These specimens were subjected to a battery of tests employing the high temperature and high speed friction test bench and EDS, TEM, and XRD. Furthermore, through the deployment of molecular dynamics simulations, this paper elaborates on the construction of both planar and spherical models of the tungsten carbide (WC) structure alongside a comprehensive structural model of C/Sb20 %. Leveraging the canonical ensemble (NVT) and a diverse array of potential functions, including Morse and embedded atom model (EAM)/alloy potentials, the study delves into the wear dynamics and sliding friction phenomena at the interface of the C/Sb20 % friction pairs. Notably, findings from the simulations reveal a dramatic decline in antimony concentration within the C/Sb20 % samples, plummeting from an initial 19.6 % to 6.89 % over an experimental period of 4000 s, signaling a substantial depletion of antimony. Concurrently, the emergence of Sb2O3 and Sb2O5 oxides was observed, indicating oxidative phenomena. Further elucidation from FIB-TEM analysis confirmed that the antimony lattice within the C/Sb20 % consistently exhibited a face-centered cubic (FCC) configuration. Integrating insights from molecular dynamics simulations with SEM analyses conducted before and after experimentation, this study unveils the extraordinary activity and "softening" of antimony flake structures under extreme conditions. This transformation, from flake to agglomerated forms, coupled with sliding friction, leads to the disruption of the graphite's internal structure, facilitating the continuous efflux of antimony and, consequently, diminishing the structural integrity of the graphite. This degradation not only compromises the graphite's mechanical properties but also escalates the risk of secondary wear through the formation of metallic oxides. • The manuscript proposes the Morse potential function method for the modeling of Sb elemental model in molecular dynamics. • The Sb layer in C/Sb produces an agglomerated stacking structure that destroys the graphite interlayer structure. • The loss of Sb in C/Sb graphite is huge, with a loss rate of 65.7 %. [ABSTRACT FROM AUTHOR]