polar bear fur waterproof and warmth research articles pdf Sunday, May 2, 2021 5:40:12 PM

Polar Bear Fur Waterproof And Warmth Research Articles Pdf

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Food Timing For Good Health, He explores his Arctic home, meets new friends, and saves some endangered whales. When becoming members of the site, you could use the full range of functions and enjoy the most exciting films.

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Metrics details. Recently, human clinical devices have been deployed in captive and free-ranging wildlife to aid in the characterization of both normal physiology and the interaction of animals with their environment, including reactions to humans. Although these devices have had a significant impact on the types and quantities of information that can be collected, their utility has been limited by internal memory capacities, the efforts required to extract and analyze information, and by the necessity to handle the animals in order to retrieve stored data.

We surgically implanted miniaturized cardiac monitors 1. These devices include wireless capabilities, which enabled frequent transmissions of detailed physiological data from bears in their remote den sites to a web-based data storage and management system.

Solar and battery powered telemetry stations transmitted detailed physiological data over the cellular network during the winter months. The system provided the transfer of large quantities of data in near-real time. For the first time, detailed physiological data were successfully transferred from an animal in the wild to a web-based data collection and management system, overcoming previous limitations on the quantities of data that could be transferred.

The system provides an opportunity to detect unusual events as they are occurring, enabling investigation of the animal and site shortly afterwards. Although the current study was limited to bears in winter dens, we anticipate that future systems will transmit data from implantable monitors to wearable transmitters, allowing for big data transfer on non-stationary animals.

Wildlife research has long benefited from the use of behavioral and physiological monitoring devices [ 1 ]—[ 12 ]. Such devices have had significant impacts on both the types and quantities of information that can be collected, but their utilities have been limited by internal memory capacities, the efforts required to extract and analyze information, and by the requirement that the animals need to be handled in order to retrieve stored data. Although human clinical devices have been successfully deployed in captive and free-ranging wildlife [ 16 ]—[ 18 ], emerging technologies with improved data recording and management capabilities hold the potential to provide even further insights into both normal physiology and the impacts of human interactions on animal behavior.

A common use of the system is for unexplained syncope fainting , in which case the implanted device can capture episodes with impaired cardiac outputs, including bradycardias unusually low heart rates , asystoles long periods without a heart beat , or tachycardias unusually high heart rates. For applications in wildlife research, the ability to capture extremes in heart rates may signal distinct physiological states, or ecological stressors or disturbances.

Previous generations of this ICM have been deployed in captive brown bears Ursus arctos and wild American black bears Ursus americanus [ 16 ]—[ 18 ]. Although these devices provided substantial insights into both behaviors and physiologies, their capabilities were hampered by limitations in internal memory capacities. Once reaching that limit, older episodes were over-written by new ones. This is appropriate for human clinical applications since this typically allows for the diagnoses of the arrhythmias of interest.

In addition, following an event, the human patient can seek medical attention at which time the device memory can be queried. By contrast, the device memories are likely to fill up in free-ranging wildlife, which cannot be regularly handled.

In this study we sought to overcome these limitations by downloading data at 2-hour intervals to a web-based data storage and management system, thereby dramatically increasing the recording resolution. Our study subjects were hibernating black bears at their natural den sites in the wild. Hibernating females give birth during mid-winter and also den with these cubs in the subsequent year [ 20 ]. Importantly, bears can defend themselves and their offspring through their maintenance of muscle strength and their capability of rousing from hibernation within seconds [ 22 ]—[ 24 ].

Black bears commonly elicit defensive posturing and high respiratory rates within seconds of being disturbed, with their hearts transitioning from the quiescent state of hibernation, to supporting bursts of activity [ 18 ]. Results of earlier studies indicate that cardiac wall thickness and function electrophysiological parameters were maintained in bears during the period of hibernation [ 17 ].

A respiratory sinus arrhythmia RSA enables the heart to rest between inspirations, with cardiac pauses of up to Although substantial research has been performed on ursid hearts during hibernation, limitations have included data collection at discrete time intervals, limited device memories, high foreign body rejection rates, and data collection from animals that were anesthetized, disturbed, or captive [ 16 ]—[ 18 ],[ 25 ]—[ 28 ].

A primary goal of this study was to further characterize the unique physiology of these animals by removing the previous limitations associated with the volume of data that could be collected, as well as to provide near-real time information about the state of the hibernating bear. In addition to improved management of wild and captive populations, a more detailed understanding of hibernation physiology may provide new insights into therapeutic approaches in human medicine [ 29 ]—[ 31 ].

Free-ranging, wild radiocollared bears in northern Minnesota Devices were placed subcutaneously in left peristernal locations with surgical sutures used to close the puncture sites. Wireless telemetry system at bear den. The insertable cardiac monitor ICM communicated with a relay station housed in a waterproof container via an antenna buried under the bear.

Transmissions to an internet site were via a cellular module attached to a timber tripod fabricated at the site. The system was powered by 12 volt batteries charged by a solar panel. Three generations of implantable monitors used by this research team.

A millimeter ruler is included as a size reference. A second sample of the current ECG is also included during data transmissions. A 5-meter long coaxial cable connected the antenna to the relay station, which was housed within an insulated, water-tight box positioned near the den. Average ventricular heart rates, heart rate variability, and activity were automatically plotted and stored on the website. The website also immediately alerted us to significant changes to any of these parameters. Image of website used for data tracking and display.

The subject bears were enrolled into a web-based clinic as patients. The site served as both a repository for data and as a means of tracking transmissions. In addition, the site automatically alerted the user when an event of interest occurred. In December , we implanted cardiac monitors in 6 hibernating black bears 3 pregnant females, 2 females with yearlings, 1 adult male.

Follow-up visits were made to each den site during early March, to check on the health of the bears and to examine the integrity of each telemetry system. Telemetered data were not received from the adult male, because he left his aboveground nest, or from one female with yearlings, because the bears had chewed through the antenna within the den. The acquisition of data increased from a maximum of 30 episodes with ECGs in prior generations of the ICM to up to episodes with ECGs plus additional sample ECGs associated with transmissions using the new technology.

Heart rate patterns exhibiting an extreme respiratory sinus arrhythmia were elicited by all animals with regular sinus pauses asystoles.

In the pregnant females, increased movements, heart rates, and muscle activities and reductions in their RSAs occurred prior to parturition. Following birthing, near complete cessation of activities occurred and the magnitudes of the RSAs returned to levels consistent with that of the early winter.

We suggest that the mothers remained more stationary immediately after birthing so as not to crush the altricial cubs, which stay warm beneath her for constant access to milk. Interestingly, the study female with yearlings did not elicit these patterns in heart rates and activity. During the period surrounding birthing, no sinus pause reached the minimum device recording threshold of 4.

Example near-real time data acquired from denning bears. A dramatic reduction in activity and heart rate variability was observed in pregnant females post parturition such as shown here , whereas a constant level of activity and heart rate variability was maintained throughout the winter for the female denning with yearlings The heart rate variability value in ms for each day is then calculated as the variability seen in the 5-minute median values over the hour period [ 19 ].

Sample ECG plots acquired from denning bears. Both were recorded from bear The maximum rate occurred the day following our visit to the den and is believed to be associated with a subsequent visit to the den by the landowners. A 5-second pause is shown for bear in the third recording and the bottom two recordings include myograms relating to skeletal muscle activity during the period of birthing for and post-parturition for Importantly, these deployed remote monitoring systems allow for the immediate detection of unusual events such as a den disturbance or something physiologically abnormal with the bear, thus providing an opportunity to quickly check the den to observe what had occurred.

For example, we previously observed denning bears that had survived an attack by wolves Canis lupus , but our observations occurred months after the attacks, thus hindering our ability to reconstruct details of the events. Telemetry system covered by snow drift. The bear at this site, which was denned in an open nest, relocated after our December visit. Author Iaizzo appears in the left side of both photos and author Laske is standing on the black telemetry box in the right panel.

During our follow-up den visits in March, we found all bears to be in good condition, but 1 of the 6 ICMs had been rejected from under the skin via a foreign body response.

We have seen this frequently in black bears [ 32 ],[ 33 ], and had anticipated that the much smaller size of these newer devices would have eliminated the problem of rejection. We do not know when this occurred because the bears had already damaged the antenna inside this den, and we could not find the device inside the den with a metal detector. We implanted a second ICM in this female in March, but again the recording system failed.

When we retrieved the system in the spring, we found that the antenna had again been damaged by the bears. Although data were not transmitted by this device, heart rate and activity trends will be downloaded using transcutaneous telemetry at a future date when handling the animal assuming the second device remains implanted.

The number of data transmissions over the study period ranged from bear to bear Factors impacting the reliability of transmissions likely included battery temperature, exposure of the solar panel to sunlight, reliability of cellular phone coverage, and the position of the bear relative to the antenna.

The impact of these factors will be investigated in future studies to enable further system refinement. This study is the first to wirelessly transmit detailed data on heart rhythms from animals in the wild. In addition, it uniquely demonstrated the ability to use a web-based data storage and management systems for recording and plotting cardiac events and trends associated with the physiological state and activity of wild bears.

Further, the use of these devices allowed for continuous monitoring of heart rhythms and physical activities, with regular downloads of ECGs strips associated with notable cardiac events.

These devices provided substantially more information than had been previously recorded, including detailed responses to birthing and cub-rearing during hibernation. They also provided an opportunity to observe physiological changes in near-real time. Although the current study was limited to bears in winter dens, we anticipate that future systems will transmit data from implantable monitors to wearable transmitters e. Written informed consent was obtained for the publication of this report and any accompanying images.

TGL is an employee of Medtronic, Inc. PAI is a consultant to Medtronic. Both are experts in heart function and the use of cardiac devices, including the use of animal models to develop medical devices for humans. Front Ecol Environ , 3: Biol Lett , 5: Poganis PJ: Bio-logging of physiological parameters in higher marine vertebrates. Deep-Sea Res II , Google Scholar.

J Exp Biol , J Biomech Eng , J Avian Biol , Biol Lett , 3: Wilson Bull , Anim Biotelem , 2: 9.

Amazing Facts About Fur: Dressing for the Arctic

Metrics details. Recently, human clinical devices have been deployed in captive and free-ranging wildlife to aid in the characterization of both normal physiology and the interaction of animals with their environment, including reactions to humans. Although these devices have had a significant impact on the types and quantities of information that can be collected, their utility has been limited by internal memory capacities, the efforts required to extract and analyze information, and by the necessity to handle the animals in order to retrieve stored data. We surgically implanted miniaturized cardiac monitors 1. These devices include wireless capabilities, which enabled frequent transmissions of detailed physiological data from bears in their remote den sites to a web-based data storage and management system.

The traditional skin clothing of the Inuit is a complex system of cold-weather garments historically made from animal hide and fur , worn by the Inuit , a group of culturally related indigenous peoples inhabiting the Arctic areas of North America and Greenland. The most basic traditional outfit consisted of a coat parka , pants, mittens, inner footwear, and outer boots made of animal hide and fur. The most common sources of hide were caribou , seals and seabirds , although other animals were used when available. Production of warm, durable clothing was an essential survival skill for the Inuit, which was traditionally passed down from adult women to girls. Preparation of clothing was an intensive, weeks-long process that occurred on a yearly cycle following traditional hunting seasons.

True enough, but some types of fur are so much warmer than others, and the reasons why may surprise you. Nunavut is actually the size of Western Europe, so even though almost the whole territory is classed as having a polar climate, there are considerable differences in weather and hours of sunlight. Time of year also makes a big difference. This is achieved primarily by means of insulation, and one of the greatest insulators is air. Or, to be more precise, trapped air. Heat travels more slowly through air than through solids or liquids, For comparison, water is 24 times more effective at conducting heat than air.


PDF | This research compares the use of fur and blubber as insulation in insulation: fur seals have dense, waterproof fur and a moderate blubber layer, while sea lions I propose that young fur seals utilize both the heat increment of feeding as well pinnipeds (seals, sea lions, and walruses), sea otters, and polar bears.


Amazing Facts About Fur: Dressing for the Arctic

Approximate worldwide winter distribution of polar bears light gray. Polar bears are distributed throughout most ice-covered seas of the Northern Hemisphere. They can be found in the Artic, the U.

Please follow this equipment list and do not bring extra gear. While this is a hotel-based trip, you will still be spending hours at a time in the elements. Space is limited in the airplanes we use. By carefully following this list you can keep your personal gear under 50 pounds without any trouble. All garments should be synthetic or wool because they are light, fast drying, and warmer when wet.

У вас есть кольцо. - Проваливайте! - зарычал немец и начал закрывать дверь.

Managing Heat

 - Мне нужен совет. Джабба встряхнул бутылочку с острой приправой Доктор Пеппер. - Выкладывай. - Может быть, все это чепуха, - сказала Мидж, - но в статистических данных по шифровалке вдруг вылезло что-то несуразное. Я надеюсь, что ты мне все объяснишь.

Беккер постарался придать своему испанскому тяжелый немецкий акцент: - Hola, hablas Aleman. - Нет, но я говорю по-английски, - последовал ответ. Беккер перешел на ломаный английский: - Спасибо. Не могли бы вы мне помочь.

Затуманенные глаза Беккера не отрываясь смотрели на торчащий из двери кусок ткани. Он рванулся, вытянув вперед руки, к этой заветной щели, из которой торчал красный хвост сумки, и упал вперед, но его вытянутая рука не достала до. Ему не хватило лишь нескольких сантиметров. Пальцы Беккера схватили воздух, а дверь повернулась. Девушка с сумкой была уже на улице. - Меган! - завопил он, грохнувшись на пол. Острые раскаленные иглы впились в глазницы.

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Hydrophobic Hood

 - Ну, что еще - до того как вы отправитесь домой. В одно мгновение Сьюзан все стало ясно. Когда Стратмор загрузил взятый из Интернета алгоритм закодированной Цифровой крепости и попытался прогнать его через ТРАНСТЕКСТ, цепная мутация наткнулась на фильтры системы Сквозь строй. Горя желанием выяснить, поддается ли Цифровая крепость взлому, Стратмор принял решения обойти фильтры. В обычных условиях такое действие считалось бы недопустимым.

Но за два дня до окончания третьего боевого дежурства в его будущем произошел резкий зигзаг. В пьяной драке Хейл случайно убил сослуживца. Корейское искусство самозащиты, тхеквондо, оказалось в большей мере смертоносным, нежели оборонительным. Военной службе пришел конец. Отсидев некоторое время в тюрьме, Хейл занялся поисками места программиста в частных компаниях. Он не скрывал от нанимателей того, что случилось с ним во время службы в морской пехоте, и стремился завоевать их расположение, предлагая работать без оплаты в течение месяца, чтобы они узнали ему цену.

Сотрудник лаборатории систем безопасности схватил ее за руку. - Мисс Флетчер. У нас вирус.

 - Самолет улетел почти пустой. Но завтра в восемь утра тоже есть… - Мне нужно узнать, улетела ли этим рейсом моя подруга. Она собиралась купить билет прямо перед вылетом. Женщина нахмурилась: - Извините, сэр.

Он убил Дэвида. Бринкерхофф положил руку ей на плечо. - Мы почти приехали, мисс Флетчер. Держитесь. Скоростной карт фирмы Кенсингтон повернул за угол и остановился.

Managing Heat

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Request PDF | Polar bears: Can their fur help us increase the efficiency of solar panels? Find, read and cite all the research you need on ResearchGate. traveling down the hairs, until it is dissipated into heat and trapped within the fur. for the Solar Thermal Use According to the Model of the Polar Bear's Fur. Article.

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