| two decades of mercury concentrations in barents sea polar bears (ursus maritimus) in relation to dietary carbon, sulfur, and nitrogen. | temporal trends of total mercury (thg) were examined in female polar bear (ursus maritimus) hair (n = 199) from the barents sea in 1995-2016. in addition, hair values of stable isotopes (n = 190-197) of carbon (δ13c), sulfur (δ34s), and nitrogen (δ15n) and information on breeding status, body condition, and age were obtained. stable isotope values of carbon and sulfur reflect dietary source (e.g., marine vs terrestrial) and the nitrogen trophic level. values for δ13c and δ34s declined by -1.62 a ... | 2020 | 32410455 |
| bioinspired "skin" with cooperative thermo-optical effect for daytime radiative cooling. | energy-saving cooling materials with strong operability are desirable for sustainable thermal management. inspired by the cooperative thermo-optical effect in the fur of a polar bear, we develop a flexible, superhydrophobic, and reusable cooling "skin" by laminating a poly(dimethylsiloxane) film with a highly scattering polyethylene aerogel. owing to its high porosity (97.9%) and tailored pore size of 3.8 ± 1.4 μm, it can achieve superior solar reflectance (r̅sun ∼ 0.96) and high transparency to ... | 2020 | 32378874 |
| the stress of arctic warming on polar bears. | arctic ecosystems are changing rapidly in response to climate warming. while arctic mammals are highly evolved to these extreme environments, particularly with respect to their stress axis, some species may have limited capacity to adapt to this change. we examined changes in key components of the stress axis (cortisol and its carrier protein-corticosteroid binding globulin [cbg]) in polar bears (ursus maritimus) from western hudson bay (n = 300) over a 33 year period (1983-2015) during which ti ... | 2020 | 32364624 |
| congenital grouped albinotic spots: new insights on the pathophysiology based on multimodal retinal imaging. | the terms "congenital grouped albinotic spots" (cgas) and "polar bear tracks" refer to a rare, benign retinal disorder of unknown etiology characterized by multiple, predominantly unilateral, variably sized, well-circumscribed, flat white retinal spots organized in groups. to date, very few cases of cgas have been reported. the authors describe a case of cgas thoroughly characterized by multimodal imaging over an 8-year follow-up, aiming to provide new insights on the pathophysiology of this ent ... | 2020 | 32348540 |
| diving deep: understanding the genetic components of hypoxia tolerance in marine mammals. | marine mammals have highly specialized physiology, exhibited in many species by extreme breath-holding capabilities that allow deep dives and extended submergence. cardiovascular control and cell-level hypoxia tolerance are key features of this phenotype. identifying genomic signatures tied to physiology will be valuable in understanding these natural model species, which may generate translational opportunities to human diseases arising from hypoxic stress or tissue injury. genomic analyses hav ... | 2020 | 32324472 |
| canadian polar bear population structure using genome-wide markers. | predicting the consequences of environmental changes, including human-mediated climate change on species, requires that we quantify range-wide patterns of genetic diversity and identify the ecological, environmental, and historical factors that have contributed to it. here, we generate baseline data on polar bear population structure across most canadian subpopulations (n = 358) using 13,488 genome-wide single nucleotide polymorphisms (snps) identified with double-digest restriction site-associa ... | 2020 | 32313629 |
| a real-time pcr assay to accurately quantify polar bear dna in fecal extracts. | dna extracted from fecal samples contains dna from the focal species, food, bacteria and pathogens. most dna quantification methods measure total dna and cannot differentiate among sources. despite the desirability of noninvasive fecal sampling for studying wildlife populations, low amounts of focal species dna make it difficult to use for next-generation sequencing (ngs), where accurate dna quantification is critical for normalization. two factors are required prior to using fecal samples in ng ... | 2020 | 32292653 |
| faecal glucocorticoid metabolites as a measure of adrenocortical activity in polar bears (ursus maritimus). | analysis of faecal glucocorticoid metabolites (fgms) is frequently applied to assess adrenocortical activity in animal conservation and welfare studies. faecal sample collection is non-invasive and feasible under field conditions. fgm levels are also less prone to circadian rhythms, episodic fluctuations and short acute stressors than glucocorticoid (gc) levels obtained from other matrices, for example blood or saliva. to investigate the suitability of fgm measurement in polar bears (ursus marit ... | 2020 | 32274062 |
| fluorine mass balance and suspect screening in marine mammals from the northern hemisphere. | there is increasing evidence that the ∼20 routinely monitored perfluoroalkyl and polyfluoroalkyl substances (pfass) account for only a fraction of extractable organofluorine (eof) occurring in the environment. to assess whether pfas exposure is being underestimated in marine mammals from the northern hemisphere, we performed a fluorine mass balance on liver tissues from 11 different species using a combination of targeted pfas analysis, eof and total fluorine determination, and suspect screening ... | 2020 | 32160740 |
| efficacy of aerial forward-looking infrared surveys for detecting polar bear maternal dens. | denned polar bears (ursus maritimus) are invisible under the snow, therefore winter-time petroleum exploration and development activities in northern alaska have potential to disturb maternal polar bears and their cubs. previous research determined forward looking infrared (flir) imagery could detect many polar bear maternal dens under the snow, but also identified limitations of flir imagery. we evaluated the efficacy of flir-surveys conducted by oil-field operators from 2004-2016. aerial flir ... | 2020 | 32106278 |
| laminated fibrous membrane inspired by polar bear pelt for outdoor personal radiation management. | outdoor cold stress often causes an undesired threat to public health, but devising an efficient strategy to achieve localized outdoor warming of the human body is still a great challenge. polar bear pelt can absorb sunlight and reflect thermal radiation generated inside the body, which helps in adapting to the cold environment. inspired by the radiation control strategy of the polar bear pelt, this study reports a porous ag/cellulose/carbon nanotube (cnt)-laminated nanofiber membrane, in which ... | 2020 | 32067458 |
| identifying individual polar bears at safe distances: a test with captive animals. | the need to recognise individuals in population and behavioural studies has stimulated the development of various identification methods. a commonly used method is to employ natural markers to distinguish individuals. in particular, the automated processing of photographs of study animals has gained interest due to the speed of processing and the ability to handle a high volume of records. however, automated processing requires high-quality photographs, which means that they need to be taken fro ... | 2020 | 32053691 |
| the clock keeps ticking: circadian rhythms of free-ranging polar bears. | life in the arctic presents organisms with multiple challenges, including extreme photic conditions, cold temperatures, and annual loss and daily movement of sea ice. polar bears (ursus maritimus) evolved under these unique conditions, where they rely on ice to hunt their main prey, seals. however, very little is known about the dynamics of their daily and seasonal activity patterns. for many organisms, activity is synchronized (entrained) to the earth's day/night cycle, in part via an endogenou ... | 2020 | 31975640 |
| interrelated ecological impacts of climate change on an apex predator. | climate change has broad ecological implications for species that rely on sensitive habitats. for some top predators, loss of habitat is expected to lead to cascading behavioral, nutritional, and reproductive changes that ultimately accelerate population declines. in the case of the polar bear (ursus maritimus), declining arctic sea ice reduces access to prey and lengthens seasonal fasting periods. we used a novel combination of physical capture, biopsy darting, and visual aerial observation dat ... | 2020 | 31925853 |
| do trait emotional intelligence and dispositional mindfulness have a complementary effect on the children's and adolescents' emotional states? | mindfulness is both a non-judgmental and present-centered awareness, which has been applied to reduce negative emotions. on the other hand, trait emotional intelligence (tei) is the way of how good people perceive their emotional intelligence abilities (perceiving, expressing, understanding, and regulating emotions), which are involved in people's social functioning. this empirical study was designed to analyze whether dispositional mindfulness (dm) and tei have a potential combined role for chi ... | 2019 | 31920855 |
| multimodal semantic revision during inferential processing: the role of inhibitory control in text and picture comprehension. | although language comprehension usually requires multimodal information, no study to date has investigated how comprehenders deal with the revision of a text's interpretation when different modalities are involved. twenty-four young adults listened to a story prompting an inference (e.g., polar bear), and then saw a picture that was either consistent (polar bear) or inconsistent but still plausible (penguin). larger negativity (n400) in the inconsistent picture indicated successful inferential m ... | 2020 | 31904356 |
| a critical review about neurotoxic effects in marine mammals of mercury and other trace elements. | marine mammals are more exposed to mercury (hg) than any others animals in the world. as many trace elements, hg it is able to impair the brain function, which could be a cause of population decline. nevertheless, these issues have been scarcely studied because of the technical and ethical difficulties. we conducted a systematic review about marine mammals' brain exposition to hg and other trace elements, and their neurotoxic effects. information was scarce and the lack of standardization of nom ... | 2020 | 31896013 |
| full genome sequence analysis of a novel adenovirus from a captive polar bear (ursus maritimus). | the presence of a novel adenovirus (adv) was detected by pcr and sequencing, in the internal organs of a captive polar bear that had died in the budapest zoo. the virus content of the samples proved to be high enough to allow for conventional sanger sequencing on pcr-amplified genomic fragments. with this approach, the sequence of the entire genome of the putative polar bear adenovirus 1 (pbadv-1) was obtained. although the genome was found to be short, consisting of 27,952 base pairs merely, wi ... | 2020 | 31870796 |
| the seasonal energetic landscape of an apex marine carnivore, the polar bear. | divergent movement strategies have enabled wildlife populations to adapt to environmental change. in recent decades, the southern beaufort sea subpopulation of polar bears (ursus maritimus) has developed a divergent movement strategy in response to diminishing sea ice where the majority of the subpopulation (73-85%) stays on the sea ice in summer and the remaining bears move to land. although declines in sea ice are generally considered a challenge to energy balance in polar bears residing in so ... | 2020 | 31850515 |
| assessment of risks of dioxins for aryl hydrocarbon receptor-mediated effects in polar bear (ursus maritimus) by in vitro and in silico approaches. | polar bear (ursus maritimus) populations accumulate dioxins and related compounds (drcs) at levels that are of health concern. the toxicities of drcs are primarily mediated via aryl hydrocarbon receptor (ahr) signaling pathway. to evaluate the sensitivity and responses to drcs in polar bears, we assessed the activation potencies of polar bear-specific ahr (pbahr) by drcs through in vitro and in silico approaches. in vitro assays showed that the pbahr was as sensitive to drcs as c3h/lpr mouse ahr ... | 2020 | 31841312 |
| pelagic vs coastal-key drivers of pollutant levels in barents sea polar bears with contrasted space-use strategies. | in the barents sea, pelagic and coastal polar bears are facing various ecological challenges that may explain the difference in their pollutant levels. we measured polychlorinated biphenyls, organochlorine pesticides, polybrominated diphenyl ethers in fat, and perfluoroalkyl substances in plasma in pelagic and coastal adult female polar bears with similar body condition. we studied polar bear feeding habits with bulk stable isotope ratios of carbon and nitrogen. nitrogen isotopes of amino acids ... | 2020 | 31823610 |
| babesia sp. infection in a zoo-housed polar bear (ursus maritimus). | a 28-year-old female polar bear (ursus maritimus) housed in a zoo in upstate new york presented with acute inappetence and lethargy. the bear's condition rapidly deteriorated, and because laboratory testing indicated severe hepatic and renal disease, the bear was humanely euthanized. examination of a blood smear from a sample collected just prior to euthanasia revealed the presence of intra-erythrocytic inclusions, which were identified as babesia sp. by pcr. although it is unclear if babesiosis ... | 2019 | 31796190 |
| multimodal imaging characteristics of congenital grouped hyper- and hypo-pigmented fundus lesions. | the imaging characteristics of congenital grouped pigmentation of the retinal pigment epithelium (cgp-rpe) and its non-pigmented variant - grouped congenital albinotic retinal pigment epithelial spots (gcarpes) are poorly defined in the literature. our case series reports their multimodal imaging characteristics across a spectrum of presentations. | 2020 | 31769080 |
| correction to: age-related differences in the attentional white bear. | this article was originally published with errors in the graphs. it has been republished with corrections. | 2020 | 31676978 |
| aviation, melting sea-ice and polar bears. | on 11 may 2019, the mauna loa, hawaii, earth system research laboratory reported the highest co2 concentration in human meteorological history. continuing co2 rise will devastate ecosystems, and ice dependent species like polar bears ultimately will disappear. commercial aviation is presently a relatively small co2 contributor, but this co2 intensive mode of transportation is projected to increase greatly. scientists and conservationists are often among the most frequent of flyers, despite their ... | 2019 | 31671313 |
| investigating the relationship between distinctive patterns of emotion regulation, trauma exposure and psychopathology among refugees resettled in australia: a latent class analysis. | background: emotion regulation difficulties are common among individuals from refugee backgrounds. little is known, however, about whether there are specific patterns relating to the types of emotion regulation strategies commonly employed by refugees, nor how this relates to psychopathology. moreover, wider literature on emotion regulation has primarily focused on examining specific emotion regulation strategies in isolation, rather than patterns of emotion regulation across multiple strategies ... | 2019 | 31552131 |
| reference intervals for blood-based biochemical analytes of southern beaufort sea polar bears. | accurate reference intervals (ris) for commonly measured blood-based analytes are essential for health monitoring programmes. baseline values for a panel of analytes can be used to monitor physiologic and pathophysiologic processes such as organ function, electrolyte balance and protein catabolism. our reference population includes 651 serum samples from polar bears (ursus maritimus) from the southern beaufort sea (sb) subpopulation sampled in alaska, usa, between 1983 and 2016. to establish ri ... | 2019 | 31548889 |
| how not to fall for the white bear: combined frequency and recency manipulations diminish negation effects on overt behavior. | processing negated mental representations comes with a price: not only are negations harder to resolve than affirmative statements, but they may even invoke ironic effects, producing the exact opposite of the intended outcome. negation effects also behave ironically when subjected to high-frequency training; when they are confronted often, the difficulty to process negations strangely increases. here we show that negation effects can be mitigated under certain circumstances. based on models of c ... | 2019 | 31517231 |
| the impact of emotional regulation strategies on pain catastrophizing in the context of interpersonal relationships. | the communal coping model suggests that pain catastrophizing may serve to elicit support from others. what is not known is how emotional regulation, namely emotional inhibition, impacts pain catastrophizing within the context of an interpersonal relationship. individuals who have a greater tendency to emotionally inhibit may have a greater likelihood to use catastrophizing as a means for seeking support, particularly in relationships characterized by satisfaction and emotional validation. | 2019 | 31513053 |
| correlates of seasonal change in the body condition of an arctic top predator. | climate-driven sea ice loss has led to changes in the timing of key biological events in the arctic, however, the consequences and rate of these changes remain largely unknown. polar bears (ursus maritimus) undergo seasonal changes in energy stores in relation to foraging opportunities and habitat conditions. declining sea ice has been linked to reduced body condition in some subpopulations, however, the specific timing and duration of the feeding period when bears acquire most of their energy s ... | 2020 | 31465583 |
| ironic and overcompensating processes under avoidance instructions in motor tasks: an attention imbalance model with golf-putting evidence. | thought-suppression research showed, when asked to suppress a given thought (e.g., a white bear), people ironically report thinking more of the suppressed thought. testing motor performance given avoidance goals (e.g., avoid putting the ball short of the target in golf) represents an interest to transfer thought-suppression findings to motor tasks. however, instead of revealing an ironic process, motor studies showed mixed results, suggesting a coexistence of ironic and overcompensating processe ... | 2019 | 31464468 |
| the use of hair as a proxy for total and methylmercury burdens in polar bear muscle tissue. | polar bears (ursus maritimus) are an ecologically important species in the arctic, whose health, and that of the people whose livelihoods depend on them, are increasingly affected by climate change and the bioaccumulation of contaminants such as mercury (hg). although methylmercury (mehg) is the toxic form of hg that biomagnifies up food webs, risk assessment studies typically only report on total hg (thg) concentrations because it is cheaper to quantify. furthermore, hair is commonly analysed f ... | 2019 | 31412508 |
| are polar bear habitat resource selection functions developed from 1985-1995 data still useful? | greenhouse-gas-induced warming in the arctic has caused declines in sea ice extent and changed its composition, raising concerns by all circumpolar nations for polar bear conservation.negative impacts have been observed in three well-studied polar bear subpopulations. most subpopulations, however, receive little or no direct monitoring, hence, resource selection functions (rsf) may provide a useful proxy of polar bear distributions. however, the efficacy of rsfs constructed from past data, that ... | 2019 | 31410267 |
| depletion of hemoglobin transcripts and long-read sequencing improves the transcriptome annotation of the polar bear (ursus maritimus). | transcriptome studies evaluating whole blood and tissues are often confounded by overrepresentation of highly abundant transcripts. these abundant transcripts are problematic, as they compete with and prevent the detection of rare rna transcripts, obscuring their biological importance. this issue is more pronounced when using long-read sequencing technologies for isoform-level transcriptome analysis, as they have relatively lower throughput compared to short-read sequencers. as a result, long-re ... | 2019 | 31379921 |
| global change-driven use of onshore habitat impacts polar bear faecal microbiota. | the gut microbiota plays a critical role in host health, yet remains poorly studied in wild species. polar bears (ursus maritimus), key indicators of arctic ecosystem health and environmental change, are currently affected by rapid shifts in habitat that may alter gut homeostasis. declining sea ice has led to a divide in the southern beaufort sea polar bear subpopulation such that an increasing proportion of individuals now inhabit onshore coastal regions during the open-water period ('onshore b ... | 2019 | 31378786 |
| plasmon-activated water can prolong existing sea-ice habitats to potentially save polar bears. | due to increasing global warming resulting from the greenhouse effect, subsequent environmental impacts and corresponding ecological influences are unavoidable. these problems are becoming more serious with time. due to rising temperatures, the survival crisis of polar bears is a very often reported issue, because polar bears are encountering shortened seasons for catching prey on their sea-ice habitat. in this work, we report an innovative and facile strategy to save polar bears via prolonging ... | 2019 | 31320695 |
| geographical assignment of polar bears using multi-element isoscapes. | wide-ranging apex predators are among the most challenging of all fauna to conserve and manage. this is especially true of the polar bear (ursus maritimus), an iconic predator that is hunted in canada and threatened by global climate change. we used combinations of stable isotopes (13c,15n,2h,18o) in polar bear hair from > 1000 individuals, sampled from across much of the canadian arctic and sub-arctic, to test the ability of stable isotopic profiles to 'assign' bears to (1) predefined managed s ... | 2019 | 31253845 |
| age-related differences in the attentional white bear. | the cognitive aging literature suggests that aging populations exhibit impairments in the proactive inhibition of attention. although proactive inhibition is often preceded by the allocation of attention toward the predicted or known spatial location of to-be-ignored stimuli, proactive allocation of attention has not been assessed in aging populations. in this study, an older and younger cohort engaged in the attentional-white-bear paradigm which measures proactive allocation of attention. in th ... | 2019 | 31183745 |
| intrinsic rivalry. can white bears help us with the other side of consciousness? | studies of consciousness have traditionally been based mainly upon the perceptual domains of consciousness. however, there is another side of consciousness, represented by various types of intrinsic conscious experiences. even though intrinsic experiences can represent up to 50% of our conscious experiences, they are still largely neglected in conscious studies. we assume there are two reasons for this. first, the field of intrinsic conscious experiences is methodologically far more problematic ... | 2019 | 31133953 |
| modeling optimal responses and fitness consequences in a changing arctic. | animals must balance a series of costs and benefits while trying to maximize their fitness. for example, an individual may need to choose how much energy to allocate to reproduction versus growth, or how much time to spend on vigilance versus foraging. their decisions depend on complex interactions between environmental conditions, behavioral plasticity, reproductive biology, and energetic demands. as animals respond to novel environmental conditions caused by climate change, the optimal decisio ... | 2019 | 31077520 |
| environmental contaminants modulate the transcriptional activity of polar bear (ursus maritimus) and human peroxisome proliferator-activated receptor alpha (ppara). | peroxisome proliferator-activated receptor alfa (ppara/nr1c1) is a ligand activated nuclear receptor that is a key regulator of lipid metabolism in tissues with high fatty acid catabolism such as the liver. here, we cloned ppara from polar bear liver tissue and studied in vitro transactivation of polar bear and human ppara by environmental contaminants using a luciferase reporter assay. six hinge and ligand-binding domain amino acids have been substituted in polar bear ppara compared to human pp ... | 2019 | 31061404 |
| how many cubs can a mum nurse? maternal age and size influence litter size in polar bears. | life-history theory predicts that females' age and size affect the level of maternal investment in current reproduction, balanced against the future reproductive effort, maintenance and survival. using long-term (30 years) individual data on 193 female polar bears ( ursus maritimus), we assessed age- and size-specific variation on litter size. litter size varied with maternal age, younger females had higher chances of losing a cub during their first months of life. results suggest an improvement ... | 2019 | 31039729 |
| the relevance of mindfulness and thought suppression to scrupulosity. | the purpose of this study was to examine the relevance of the mindfulness and thought suppression to scrupulosity, or religious obsessions. it was hypothesized that scrupulosity would be negatively associated trait mindfulness and positively associated with thought suppression. it was also hypothesized that thought suppression and mindfulness would mediate the association between scrupulosity and symptoms of obsessive-compulsive disorder (ocd). a survey-based study was conducted to test these hy ... | 2019 | 32746386 |
| estimating the energy expenditure of free-ranging polar bears using tri-axial accelerometers: a validation with doubly labeled water. | measures of energy expenditure can be used to inform animal conservation and management, but methods for measuring the energy expenditure of free-ranging animals have a variety of limitations. advancements in biologging technologies have enabled the use of dynamic body acceleration derived from accelerometers as a proxy for energy expenditure. although dynamic body acceleration has been shown to strongly correlate with oxygen consumption in captive animals, it has been validated in only a few st ... | 2019 | 31015999 |
| thermal insulation design bioinspired by microstructure study of penguin feather and polar bear hair. | nature is an amazing source of inspiration for the design of thermal insulation strategies, which are key for saving energy. in nature, thermal insulation structures, such as penguin feather and polar bear hair, are well developed; enabling the animals' survival in frigid waters. the detailed microscopy investigations conducted in this study, allowed us to perform microstructural analysis of these thermally insulating materials, including statistical measurements of keratin fiber and pore dimens ... | 2019 | 31005607 |
| a stochastic game model of searching predators and hiding prey. | when the spatial density of both prey and predators is very low, the problem they face may be modelled as a two-person game (called a 'search game') between one member of each type. following recent models of search and pursuit, we assume the prey has a fixed number of heterogeneous 'hiding' places (for example, ice holes for a seal to breathe) and that the predator (maybe polar bear) has the time or energy to search a fixed number of these. if he searches the actual hiding location and also suc ... | 2019 | 30940027 |
| age and seasonal variation in testis and baculum morphology in east greenland polar bears (ursus maritimus) in relation to high concentrations of persistent organic pollutants. | persistent organic pollutants (pops) are found in high concentrations in the artic. polar bears (ursus maritimus) are one of the most exposed mammals in the arctic and are thereby vulnerable to reproductive disruption. the aim of this study was to investigate male polar bear reproduction based on a detailed evaluation of testis histology and to assess possible effects of environmental chemicals on male polar bear reproduction. reproductive groups that were identified based on histology were as f ... | 2019 | 30928855 |
| psychological care augmented by telemedicine after a polar bear encounter at an arctic research station: a case report. | background: psychologically stressful events can be particularly challenging in the wilderness or extreme environments due to a lack of immediate medical or psychological support. telemedicine consultations may provide a means to supply medical providers in austere environments with expertise when confronted with these situations. methods: in this study, we detail a case of psychological care imparted to residents at a remote, arctic research station after they encountered a polar bear. the heal ... | 2020 | 30912705 |
| state of knowledge on current exposure, fate and potential health effects of contaminants in polar bears from the circumpolar arctic. | the polar bear (ursus maritimus) is among the arctic species exposed to the highest concentrations of long-range transported bioaccumulative contaminants, such as halogenated organic compounds and mercury. contaminant exposure is considered to be one of the largest threats to polar bears after the loss of their arctic sea ice habitat due to climate change. the aim of this review is to provide a comprehensive summary of current exposure, fate, and potential health effects of contaminants in polar ... | 2019 | 30901781 |
| accounting for phenology in the analysis of animal movement. | the analysis of animal tracking data provides important scientific understanding and discovery in ecology. observations of animal trajectories using telemetry devices provide researchers with information about the way animals interact with their environment and each other. for many species, specific geographical features in the landscape can have a strong effect on behavior. such features may correspond to a single point (eg, dens or kill sites), or to higher dimensional subspaces (eg, rivers or ... | 2019 | 30859552 |
| from polar bears to cell polarity and everything in between: 2018 in review. | | 2019 | 30808619 |
| unpacking cognitive emotion regulation in eating disorder psychopathology: the differential relationships between rumination, thought suppression, and eating disorder symptoms among men and women. | while previous literature suggests that emotion dysregulation is a salient factor contributing to the onset and maintenance of eating disorders (eds), less is known about how maladaptive, cognitively oriented regulation strategies such as rumination and thought suppression may be uniquely related to ed symptoms in men and women. the present study sought to examine the independent associations of ruminative brooding and thought suppression with ed symptoms, after controlling for negative affect i ... | 2019 | 30677597 |
| distract yourself: prediction of salient distractors by own actions and external cues. | distracting sensory events can capture attention, interfering with the performance of the task at hand. we asked: is our attention captured by such events if we cause them ourselves? to examine this, we employed a visual search task with an additional salient singleton distractor, where the distractor was predictable either by the participant's own (motor) action or by an endogenous cue; accordingly, the task was designed to isolate the influence of motor and non-motor predictive processes. we f ... | 2019 | 30588545 |
| temporal trends of persistent organic pollutants in barents sea polar bears ( ursus maritimus) in relation to changes in feeding habits and body condition. | temporal trends of persistent organic pollutants (pops: pcbs, oh-pcbs, p, p'-dde, hcb, β-hch, oxychlordane, bde-47, and 153) in relation to changes in feeding habits and body condition in adult female polar bears ( ursus maritimus) from the barents sea subpopulation were examined over 20 years (1997-2017). all 306 samples were collected in the spring (april). both stable isotope values of nitrogen (δ15n) and carbon (δ13c) from red blood cells declined over time, with a steeper trend for δ13c bet ... | 2019 | 30548071 |
| potential clinical utility of erc-2 yeast phase lysate antigen for antibody detection in dogs with blastomycosis. | four blastomyces antigens erc-2 (b. gilchristii, dog, wisconsin), b5929 (human, minnesota), 597 (human, wisconsin), and t-27 (polar bear, tennessee) were tested against 31 serum specimens from dogs with blastomycosis and 19 from healthy dogs. all antigens detected antibody; efficacy varied. erc-2 showed the highest elisa mean absorbance value of 3.00 followed by t-27. test performance varied by sample geographic origin. further study is needed to determine if erc-2 antigens may be clinically use ... | 2019 | 30544205 |
| integrated population modeling provides the first empirical estimates of vital rates and abundance for polar bears in the chukchi sea. | large carnivores are imperiled globally, and characteristics making them vulnerable to extinction (e.g., low densities and expansive ranges) also make it difficult to estimate demographic parameters needed for management. here we develop an integrated population model to analyze capture-recapture, radiotelemetry, and count data for the chukchi sea subpopulation of polar bears (ursus maritimus), 2008-2016. our model addressed several challenges in capture-recapture studies for polar bears by incl ... | 2018 | 30429493 |
| surface free energy of a hard-sphere fluid at curved walls: deviations from morphometric thermodynamics. | we report molecular-dynamics (md) simulation results for the surface free energy of a hard-sphere fluid at cylindrical and spherical hard walls of different radii. the precision of the results is much higher than that in our previous study [b. b. laird et al., phys. rev. e 86, 060602 (2012)], allowing us to estimate the size of deviations from the predictions of morphometric thermodynamics (mt). we compare our results to the analytical expressions for the surface energy as a function of wall rad ... | 2018 | 30409005 |
| heightened immune system function in polar bears using terrestrial habitats. | climate change is altering the distribution of some wildlife species while warming temperatures are facilitating the northward expansion of pathogens, potentially increasing disease risk. melting of arctic sea ice is increasingly causing polar bears (ursus maritimus) of the southern beaufort sea (sbs) to spend summer on land, where they may encounter novel pathogens. here, we tested whether sbs polar bears on shore during summer exhibited greater immune system activity than bears remaining on th ... | 2019 | 30403916 |
| concentrations of legacy and new contaminants are related to metabolite profiles in hudson bay polar bears. | there are very few metabolomics assessments based on field accumulated, uncontrolled contaminant exposures in wildlife, particularly in the arctic. in the present study, targeted metabolomics and contaminant data were analyzed together to assess potential influences of contaminant exposure on the hepatic metabolome of male polar bears (n = 29) from the southern and western hudson bay (shb and whb respectively), canada. the 29 metabolites identified as important in the differentiation of the two ... | 2019 | 30384230 |
| hundreds of unrecognized halogenated contaminants discovered in polar bear serum. | exposure of polar bears (ursus maritimus) to persistent organic pollutants was discovered in the 1970s, but recent evidence suggests the presence of unknown toxic chemicals in their blood. protein and phospholipid depleted serum was stirred with polyethersulfone capillaries to extract a broad range of analytes, and nontarget mass spectrometry with "fragmentation flagging" was used for detection. hundreds of analytes were discovered belonging to 13 classes, including novel polychlorinated bipheny ... | 2018 | 30376612 |
| polar bears turn to whale meat as their hunting grounds melt. | | 2018 | 30327510 |
| tracking arctic marine mammal resilience in an era of rapid ecosystem alteration. | global warming is significantly altering arctic marine ecosystems. specifically, the precipitous loss of sea ice is creating a dichotomy between ice-dependent polar bears and pinnipeds that are losing habitat and some cetaceans that are gaining habitat. while final outcomes are hard to predict for the many and varied marine mammal populations that rely on arctic habitats, we suggest a simplified framework to assess status, based upon ranking a population's size, range, behavior, and health. this ... | 2018 | 30300350 |
| effects of tanning on the stable isotopic compositions of hair. | we investigated the effect of tanning on the stable isotopic compositions (cnhos) of hair keratin. samples of hair from polar bear (ursus maritimus) hides were collected before and after the tanning process from a commercial tannery. with the exception of sulphur isotopes, tanning did not alter the stable isotopic compositions of hair. δ34s values were slightly more positive (1 per mil) in hair that had gone through the tanning process, likely as a result of the tanning agent, alum (al2(so4)3) o ... | 2018 | 30286339 |
| development of on-shore behavior among polar bears (ursus maritimus) in the southern beaufort sea: inherited or learned? | polar bears (ursus maritimus) are experiencing rapid and substantial changes to their environment due to global climate change. polar bears of the southern beaufort sea (sb) have historically spent most of the year on the sea ice. however, recent reports from alaska indicate that the proportion of the sb subpopulation observed on-shore during late summer and early fall has increased. our objective was to investigate whether this on-shore behavior has developed through genetic inheritance, asocia ... | 2018 | 30250663 |
| polar bear health in environmental science and translational medicine. | | 2018 | 30227316 |
| metagenomic composition analysis of an ancient sequenced polar bear jawbone from svalbard. | the sequencing of ancient dna samples provides a novel way to find, characterize, and distinguish exogenous genomes of endogenous targets. after sequencing, computational composition analysis enables filtering of undesired sources in the focal organism, with the purpose of improving the quality of assemblies and subsequent data analysis. more importantly, such analysis allows extinct and extant species to be identified without requiring a specific or new sequencing run. however, the identificati ... | 2018 | 30200636 |
| thermodynamics of the hard-disk fluid at a planar hard wall: generalized scaled-particle theory and monte carlo simulation. | a generalized scaled-particle theory for the uniform hard-disk mixture is derived in the spirit of the white bear ii free energy of the hard-sphere fluid [h. hansen-goos and r. roth, j. phys. c: condens. matter 18, 8413 (2006)]. the theory provides a very simple result for the interfacial free energy γ of the hard-disk fluid at a planar hard wall (which in d = 2 is a line) in terms of the equation of state. to complement and assess the theory, we perform monte carlo simulations from which we obt ... | 2018 | 30193513 |
| evidence for ussurian tube-nosed bats (murina ussuriensis) hibernating in snow. | surviving winter is a challenge for endothermic animals living at high latitudes. in bats, some species migrate to milder climates in winter, but others presumably stay and hibernate in thermally buffered roosts. however, we know little about where, or in what roosts bats hibernate. ussurian tube-nosed bats (murina ussuriensis) have occasionally been observed under or near the surface of snow. we collected the details of those accounts and used our own observations to conclude that these bats hi ... | 2018 | 30104736 |
| the international mouse phenotyping consortium (impc): a functional catalogue of the mammalian genome that informs conservation. | the international mouse phenotyping consortium (impc) is building a catalogue of mammalian gene function by producing and phenotyping a knockout mouse line for every protein-coding gene. to date, the impc has generated and characterised 5186 mutant lines. one-third of the lines have been found to be non-viable and over 300 new mouse models of human disease have been identified thus far. while current bioinformatics efforts are focused on translating results to better understand human disease pro ... | 2018 | 30100824 |
| mean-field density functional theory of a nanoconfined classical, three-dimensional heisenberg fluid. ii. the interplay between molecular packing and orientational order. | as in paper i of this series of papers [s. m. cattes et al., j. chem. phys. 144, 194704 (2016)], we study a heisenberg fluid confined to a nanoscopic slit pore with smooth walls. the pore walls can either energetically discriminate specific orientations of the molecules next to them or are indifferent to molecular orientations. unlike in paper i, we employ a version of classical density functional theory that allows us to explicitly account for the stratification of the fluid (i.e., the formatio ... | 2018 | 30089380 |
| novel divergent polar bear-associated mastadenovirus recovered from a deceased juvenile polar bear. | polar bears in captivity can be exposed to opportunistic pathogens not present in their natural environments. a 4-month-old polar bear (ursus maritimus) living in an isolated enclosure with his mother in the tierpark berlin, berlin, germany, was suffering from severe abdominal pain, mild diarrhea, and loss of appetite and died in early 2017. histopathology revealed severe hepatic degeneration and necrosis without evidence of inflammation or inclusion bodies, although a viral infection had been s ... | 2018 | 30045965 |
| isotopic composition of blood of polar bears (ursus maritimus) of the kara-barents sea population. | the data on the content of carbon and nitrogen isotopes in the blood samples of polar bears obtained in the present study confirm that polar bears in the taimyr region (and the kara-barents sea population in general) are partly dependent on the resources of terrestrial origin. however the "terrestrial carbon" evidently reaches bears' tissues indirectly, via marine food webs utilizing organic carbon brought into the polar basin by siberian rivers. | 2018 | 30009348 |
| vulnerability of arctic marine mammals to vessel traffic in the increasingly ice-free northwest passage and northern sea route. | the fabled northwest passage and northern sea route that were once the quests of early western explorers are now increasingly sea ice-free, with routine vessel transits expected by midcentury. the potential impacts of this novel vessel traffic on endemic arctic marine mammal (amm) species are unknown despite their critical social and ecological roles in the ecosystem and widely recognized susceptibility to ice loss. we developed a vulnerability assessment of 80 subpopulations of seven amm specie ... | 2018 | 29967138 |
| evolutionary adaptation and amyloid formation: does the reduced amyloidogenicity and cytotoxicity of ursine amylin contribute to the metabolic adaption of bears and polar bears? | much of our knowledge of diabetes is derived from studies of rodent models. an alternative approach explores evolutionary solutions to physiological stress by studying organisms that face challenging metabolic environments. polar bears eat an enormously lipid-rich diet without deleterious metabolic consequences. in contrast, transgenic rodents expressing the human neuropancreatic polypeptide hormone amylin develop hyperglycemia and extensive pancreatic islet amyloid when fed a high fat diet. the ... | 2017 | 29955200 |
| aquatic behaviour of polar bears (ursus maritimus) in an increasingly ice-free arctic. | polar bears are ice-associated marine mammals that are known to swim and dive, yet their aquatic behaviour is poorly documented. reductions in arctic sea ice are clearly a major threat to this species, but understanding polar bears' potential behavioural plasticity with respect to the ongoing changes requires knowledge of their swimming and diving skills. this study quantified time spent in water by adult female polar bears (n = 57) via deployment of various instruments bearing saltwater switche ... | 2018 | 29946080 |
| accumulation of plastic debris and associated contaminants in aquatic food webs. | we present a generic theoretical model (microweb) that simulates the transfer of microplastics and hydrophobic organic chemicals (hoc) in food webs. we implemented the model for an arctic case comprised of nine species including atlantic cod and polar bear as top predator. we used the model to examine the effect of plastic ingestion on trophic transfer of microplastics and persistent hocs (pcbs) and metabolizable hocs (pahs), spanning a wide range of hydrophobicities. in a scenario where hocs in ... | 2018 | 29925231 |
| immunologic, reproductive, and carcinogenic risk assessment from pop exposure in east greenland polar bears (ursus maritimus) during 1983-2013. | polar bears (ursus maritimus) are among the world's highest trophic level marine predators and as such have some of the highest tissue concentrations of organohalogen contaminants (ohcs) among arctic biota. in this paper we present the results of a three decade (1983-2013) risk assessment of ohc exposure and effects on reproduction, immunity, and cancer (genotoxicity) in polar bears from central east greenland. risk of adverse effects are evaluated using a risk quotient (rq) approach with deriva ... | 2018 | 29883763 |
| effects of biometrics, location and persistent organic pollutants on blood clinical-chemical parameters in polar bears (ursus maritimus) from svalbard, norway. | in the present study, blood clinical-chemical parameters (bccps) were analysed in 20 female and 18 male svalbard polar bears (ursus maritimus) captured in spring 2007. the aim was to study how age, body condition (bc), biometrics, plasma lipid content and geographical location may confound the relationship between persistent organic pollutants (pops) including pcbs, hcb, chlordanes, ddts, hchs, mirex and oh-pcbs and the concentrations of 12 specific bccps (hematocrit [hct], hemoglobin [hb], aspa ... | 2018 | 29860211 |
| white bear suppression inventory: translation and cross-cultural adaptation to brazilian portuguese. | introduction intrusive thoughts may cause a significant level of distress, since some individuals evaluate the content of those thoughts as aversive. suppression of intrusive thoughts is one of the strategies adopted by these individuals, which increases the level of distress. suppression of thoughts may be present as one of the factors that maintain different psychological disorders. objective to describe the translation and adaptation into brazilian portuguese of the white bear suppression inv ... | 2018 | 29668821 |
| heritability of body size in the polar bears of western hudson bay. | among polar bears (ursus maritimus), fitness is dependent on body size through males' abilities to win mates, females' abilities to provide for their young and all bears' abilities to survive increasingly longer fasting periods caused by climate change. in the western hudson bay subpopulation (near churchill, manitoba, canada), polar bears have declined in body size and condition, but nothing is known about the genetic underpinnings of body size variation, which may be subject to natural selecti ... | 2018 | 29667364 |
| targeting acceptance in the management of food craving: the mediating roles of eating styles and thought suppression. | food craving is now widely considered to be a cognitively motivated state. acceptance-based treatments are effective in reducing the adverse impact of food cravings on consumption, via a hypothesized decrease in experiential avoidance. the mechanisms that drive the success of acceptance-based management of craving remain to be empirically tested. this study examined the role of eating styles and thought suppression as mediators in the relationship between experiential avoidance and craving. part ... | 2018 | 29665461 |
| corrigendum: internet blogs, polar bears, and climate-change denial by proxy. | [this corrects the article doi: 10.1093/biosci/bix133.]. | 2018 | 29664475 |
| internet blogs, polar bears, and climate-change denial by proxy. | increasing surface temperatures, arctic sea-ice loss, and other evidence of anthropogenic global warming (agw) are acknowledged by every major scientific organization in the world. however, there is a wide gap between this broad scientific consensus and public opinion. internet blogs have strongly contributed to this consensus gap by fomenting misunderstandings of agw causes and consequences. polar bears (ursus maritimus) have become a "poster species" for agw, making them a target of those deny ... | 2018 | 29662248 |
| corrigendum: internet blogs, polar bears, and climate-change denial by proxy. | | 2018 | 29608770 |
| persistent organic pollutants and penile bone mineral density in east greenland and canadian polar bears (ursus maritimus) during 1996-2015. | persistent organic pollutants (pops) are long-range transported to the arctic via atmospheric and oceanic currents, where they biomagnify to high concentrations in the tissues of apex predators such as polar bears (ursus maritimus). a major concern of pop exposure is their physiological effects on vital organ-tissues posing a threat to the health and survival of polar bears. here we examined the relationship between selected pops and baculum bone mineral density (bmd) in the east greenland and s ... | 2018 | 29522985 |
| range contraction and increasing isolation of a polar bear subpopulation in an era of sea-ice loss. | climate change is expected to result in range shifts and habitat fragmentation for many species. in the arctic, loss of sea ice will reduce barriers to dispersal or eliminate movement corridors, resulting in increased connectivity or geographic isolation with sweeping implications for conservation. we used satellite telemetry, data from individually marked animals (research and harvest), and microsatellite genetic data to examine changes in geographic range, emigration, and interpopulation conne ... | 2018 | 29468025 |
| a thermally insulating textile inspired by polar bear hair. | animals living in the extremely cold environment, such as polar bears, have shown amazing capability to keep warm, benefiting from their hollow hairs. mimicking such a strategy in synthetic fibers would stimulate smart textiles for efficient personal thermal management, which plays an important role in preventing heat loss and improving efficiency in house warming energy consumption. here, a "freeze-spinning" technique is used to realize continuous and large-scale fabrication of fibers with alig ... | 2018 | 29443435 |
| high-energy, high-fat lifestyle challenges an arctic apex predator, the polar bear. | regional declines in polar bear (ursus maritimus) populations have been attributed to changing sea ice conditions, but with limited information on the causative mechanisms. by simultaneously measuring field metabolic rates, daily activity patterns, body condition, and foraging success of polar bears moving on the spring sea ice, we found that high metabolic rates (1.6 times greater than previously assumed) coupled with low intake of fat-rich marine mammal prey resulted in an energy deficit for m ... | 2018 | 29420288 |
| choose your poison-space-use strategy influences pollutant exposure in barents sea polar bears. | variation in space-use is common within mammal populations. in polar bears, ursus maritimus, some individuals follow the sea ice (offshore bears) whereas others remain nearshore yearlong (coastal bears). we studied pollutant exposure in relation to space-use patterns (offshore vs coastal) in adult female polar bears from the barents sea equipped with satellite collars (2000-2014, n = 152). first, we examined the differences in home range (hr) size and position, body condition, and diet proxies ( ... | 2018 | 29363970 |
| high contributions of sea ice derived carbon in polar bear (ursus maritimus) tissue. | polar bears (ursus maritimus) rely upon arctic sea ice as a physical habitat. consequently, conservation assessments of polar bears identify the ongoing reduction in sea ice to represent a significant threat to their survival. however, the additional role of sea ice as a potential, indirect, source of energy to bears has been overlooked. here we used the highly branched isoprenoid lipid biomarker-based index (h-print) approach in combination with quantitative fatty acid signature analysis to sho ... | 2018 | 29360849 |
| demographic and temporal variations in immunity and condition of polar bears (ursus maritimus) from the southern beaufort sea. | assessing the health and condition of animals in their natural environment can be problematic. many physiological metrics, including immunity, are highly influenced by specific context and recent events to which researchers may be unaware. thus, using a multifaceted physiological approach and a context-specific analysis encompassing multiple time scales can be highly informative. ecoimmunological tools in particular can provide important indications to the health of animals in the wild. we colle ... | 2017 | 29356384 |
| potential impacts of offshore oil spills on polar bears in the chukchi sea. | sea ice decline is anticipated to increase human access to the arctic ocean allowing for offshore oil and gas development in once inaccessible areas. given the potential negative consequences of an oil spill on marine wildlife populations in the arctic, it is important to understand the magnitude of impact a large spill could have on wildlife to inform response planning efforts. in this study we simulated oil spills that released 25,000 barrels of oil for 30 days in autumn originating from two s ... | 2018 | 29339335 |
| a compendium and functional characterization of mammalian genes involved in adaptation to arctic or antarctic environments. | many mammals are well adapted to surviving in extremely cold environments. these species have likely accumulated genetic changes that help them efficiently cope with low temperatures. it is not known whether the same genes related to cold adaptation in one species would be under selection in another species. the aims of this study therefore were: to create a compendium of mammalian genes related to adaptations to a low temperature environment; to identify genes related to cold tolerance that hav ... | 2017 | 29297313 |
| persistent organic pollutants, skull size and bone density of polar bears (ursus maritimus) from east greenland 1892-2015 and svalbard 1964-2004. | we investigated skull size (condylobasal length; cbl) and bone mineral density (bmd) in polar bears (ursus maritimus) from east greenland (n = 307) and svalbard (n = 173) sampled during the period 1892-2015 in east greenland and 1964-2004 at svalbard. adult males from east greenland showed a continuous decrease in bmd from 1892 to 2015 (linear regression: p < 0.01) indicating that adult male skulls collected in the early pre-pollution period had the highest bmd. a similar decrease in bmd over ti ... | 2018 | 29287182 |
| morphology of the lingual papillae of the polar bear (ursus maritimus). | we examined the dorsal lingual surfaces of a newborn and an old polar bears by using scanning electron microscopy. in the newborn polar bear, the filiform papilla on the lingual apex was cylindrical in shape. the connective tissue core of the filiform papillae was needle-shaped and that of the fungiform papillae was funnel-shaped. the filiform papillae on the lingual body was dome-shaped. the connective tissue core of the filiform papillae was u-shaped and that of the fungiform papillae was colu ... | 2017 | 29249734 |
| phenotypic plasticity and climate change: can polar bears respond to longer arctic summers with an adaptive fast? | plasticity in the physiological and behavioural responses of animals to prolonged food shortages may determine the persistence of species under climate warming. this is particularly applicable for species that can "adaptively fast" by conserving protein to protect organ function while catabolizing endogenous tissues. some ursids, including polar bears (ursus maritimus), adaptively fast during winter hibernation-and it has been suggested that polar bears also employ this strategy during summer. w ... | 2018 | 29197040 |
| multiple-stressor effects in an apex predator: combined influence of pollutants and sea ice decline on lipid metabolism in polar bears. | there is growing evidence from experimental and human epidemiological studies that many pollutants can disrupt lipid metabolism. in arctic wildlife, the occurrence of such compounds could have serious consequences for seasonal feeders. we set out to study whether organohalogenated compounds (ohcs) could cause disruption of energy metabolism in female polar bears (ursus maritimus) from svalbard, norway (n = 112). we analyzed biomarkers of energy metabolism including the abundance profiles of nine ... | 2017 | 29184161 |
| environmental and behavioral changes may influence the exposure of an arctic apex predator to pathogens and contaminants. | recent decline of sea ice habitat has coincided with increased use of land by polar bears (ursus maritimus) from the southern beaufort sea (sb), which may alter the risks of exposure to pathogens and contaminants. we assayed blood samples from sb polar bears to assess prior exposure to the pathogens brucella spp., toxoplasma gondii, coxiella burnetii, francisella tularensis, and neospora caninum, estimate concentrations of persistent organic pollutants (pops), and evaluate risk factors associate ... | 2017 | 29038498 |
| optimal marine mammal welfare under human care: current efforts and future directions. | marine mammals include cetaceans, pinnipeds, sirenians, sea otters and polar bears, many of which are charismatic and popular species commonly kept under human care in zoos and aquaria. however, in comparison with their fully terrestrial counterparts their welfare has been less intensively studied, and their partial or full reliance on the aquatic environment leads to unique welfare challenges. in this paper we attempt to collate and review the research undertaken thus far on marine mammal welfa ... | 2018 | 28927965 |
| sea-ice 'treadmill' speeds up for polar bears. | | 2017 | 32076341 |