Crittercams and Positron Emission Tomography - Term Paper Example

Media Major Essay Introduction The progress of science and technology has been tremendous. There are inventions that defy even the wildest imaginations of humans. In addition, technological inventions are sometimes being put to use in diverse and unexpected areas. Crittercams and Positron Emission Tomography are two such applications. Wildlife is on the decline, and many species get extinct frequently. This alarming situation has resulted in renewed efforts to preserve wildlife. Some of the technical tools employed in this effort are voice recorders, satellite telemetry, manned underwater video cameras and Crittercams. The latter are unmanned microprocessor based measuring gadgets. Crittercams are animal borne and thus provide continuous footage of habitats and animal habits that had previously not been thought possible. Another such technological tool is the Positron Emission Tomography (PET). A minute quantity of positron emitting radioactive material is ingested into the body, in such a manner that it reaches an organ or area suspected of being diseased. The emitted positrons are annihilated on coming into contact with electrons and the resultant release of pure energy is detected by sophisticated machinery. This provides an image of that organ or area, which is of significant use in diagnosis. PET has been of great help in diagnosing cancer, brain disorders and heart disease. It is an excellent non – invasive method for differentiating between malignant and non – malignant tumors. Thus, a process of nuclear physics has found widespread use in medical diagnosis. Crittercam Crittercams were initially used for underwater photography. They have provided considerable knowledge about animals. Crittercams make it possible to film animals from a distance and image them remotely. Many of the programs telecast on the National Geographic Channel are taken with Crittercams (Haraway, 2007, Pp 258-259). Operation of Crittercams is unmanned, and there is no necessity of a camera operator. Crittercam cameras are attached to animals and one video was taken by installing a Crittercam on a seal’s back. Wherever the seal swam, videos were shot, which provided considerable information to scientists, regarding the Hawaiian monk seals and their ability to save the life of other animals. Greg Marshall, a marine biologist invented this technology, to find out about the life of marine creatures (Wichlegren, 10/23/98, P 8). Marshall and other scientists have conducted various experiments with Crittercams, by attaching the latter to seals, turtles and sperm whales. Sperm whales are giant mammals, which live in oceans. They dive to great depths, and these cameras were attached to sperm whales, to explore their secret life. These whales feed on Architeuthis, a type of giant squid. The Crittercams attached to sperm whales provided vast knowledge about these squids. For this reason, they had selected sperm whales as the carrier of the Crittercam (Wichlegren, 10/23/98, P 8). Architeuthis is one of the most mysterious and elusive species on Earth and no scientist has seen a living specimen. The dead squid of this family have been found on the beaches and they are very large with huge eyeballs, and a large number of arms and tentacles. These arms and tentacles are lined with very powerful suckers. These squids grow bigger than a truck, and constitute the prey of sperm whales, which are much larger than the squids and possess stronger and more powerful jaws with huge teeth (Wichlegren, 10/23/98, P 8). Initially, Marshall approached a group of sperm whales with fear and managed to attach a Crittercam to the back of a sperm whale. After twenty minutes, the camera detached itself from the whale’s back and floated to the surface. The scientists observed the video recordings of the camera, and obtained substantial information about the behavior of these gigantic animals at great depths (Wichlegren, 10/23/98, P 8). The video also showed four whales swimming side by side with their bodies often touching each other. This established that sperm whales feed in groups. The camera also recorded the sounds produced by the sperm whales. These sounds had not been heard by humans until then. They included growls, grunts and squeals. Each whale produces sounds with a characteristic frequency. The scientists are now trying to decipher the language of the whales through these recordings (Wichlegren, 10/23/98, P 8). One of these whales emitted a long buzzing sound, which was intended to assist the whale in hunting prey, in the depths of the ocean. The energy produced by the sound resonates in the waters, and allows the whale to determine the exact location of its prey. This is known as echolocation (Wichlegren, 10/23/98, P 8). The Crittercam has also helped to make discoveries in the life patterns of several other animals. For instance, the use of Crittercam on Hawaiian monk seals helped to protect them from extinction. These seals constitute an endangered species; and their numbers have reduced by nearly half during the past forty years. Marine scientists attached a Crittercam on the back of a monk seal to determine their life pattern, and determine the cause for the drastic reduction in their numbers. The Crittercam videos disclosed that starvation was the primary cause for this reduction in their population (Wichlegren, 10/23/98, P 8). In the past, scientists had assumed that seals hunt in shallow waters. However, the Crittercam videotapes showed that the Hawaiian monk seals hunt in the bed of the deep ocean. The monk seals descend to the rocks at the bottom of the ocean, and hunt for octopuses and crabs; and dig in the sand of the ocean floor, to unearth the fish that bury themselves there. Another important discovery made was that humans concentrate on these deep waters for their fishing activities (Wichlegren, 10/23/98, P 8). Although, shallow waters are protected from fishing by humans, the deep waters are not protected in this manner. Thus, humans deprive Hawaiian monk seals of their food, and cause them to starve. The Crittercam has revolutionized the manner in which scientists and biologists think and perceive. It has changed scientific perceptions about animal life, especially marine life. It is anticipated that in the future, that the Crittercam may make it possible to obtain videos of even the elusive giant squids (Wichlegren, 10/23/98, P 8). With a 340 line resolution, the Crittercam works even in total darkness. It can capture light as less as 3 lux luminance, which is equivalent to the level of light on a moonless night. It can transmit images up to 500 feet. Its weight depends on the size of its battery. In other words, the duration of use determines its weight. In general, a nine – volt battery is used for short – periods of usage. For one week’s usage, a one-pound battery has to be used. The Crittercam was initially tested on domestic cats and dogs, and had been intended for use on Alaskan grizzly bears and peregrine falcons (Berger, 03/26/2001, P 20). The National Geographic first used Crittercams, chiefly on aquatic life. Many televised programs like the ‘Great White Shark’ and ‘Sea Monsters’ aired by the NBC, and the ‘Tiger Shark’ of the CNBC were recorded with Crittercams. Technological advances have diminished the size of these cameras. Their dimensions are ten inches in length and 3.5 inches in diameter, and a weight of just 2.5 pounds (Berger, 03/26/2001, P 20). Marshall has stated that this equipment will not restrict animals in their behavior. Cameras that are used with whales have suction caps, while those used with sharks have dorsal fin clips. The compacting of the circuits of these cameras and the use of wireless technology has further reduced their size and weight. They record underwater events as images, and the terrestrial cameras can even transmit images to the base station (Berger, 03/26/2001, P 20). AVEDs or animal borne video and environmental data collection systems are sensor systems that merge data relating to sound, temperature, location and other areas with data collected from the animal’s perception. An exclusive view, regarding the behavior of animals and the methods employed by them in foraging for food, is provided by AVEDs, including material that is of immense help in conducting research on issues relating to wildlife damage and animal energetics. The development of AVEDs used in marine research, has outstripped its terrestrial cousin. Marine AVEDs are technologically far superior to the land based AVEDs, and store data in places located within themselves (Moll, et al., May 2009). Terrestrial systems are transmission based and used with creatures that are comfortable with men or species that can be easily followed. White tailed deer were the chosen for deploying the first terrestrial AVED. This pioneer among AVEDs consisted of a camera, microcomputer, sensor board and battery packs, all available commercially. It provided novel insights into animal behavior. As such, it is the new technologies that bring about discoveries in a number of ecological areas, chiefly due to enhancing the precision of extant methods, increasing the amount of data and by procuring information that had not been possible to garner in the past (Moll, et al., May 2009). AVEDs are sophisticated means of remotely detecting and measuring animal functions, conditions or activities, and behavior in its natural habitat. In addition, such systems enable the collecting of data relating to animal location and animal physiology. On many an occasion, such data was collected by means of sensors attached to some other species. Data collection is uninterrupted and this enables detailed observations, in comparison to other methods (Moll, Millspaugh, Beringer, Sartwell, & He, A new ‘view’ of ecology and conservation through animal-borne video systems, December 2007). For instance, activities, such as, foraging dynamics, interaction with other species, transmission of diseases and reproduction demand detailed data, and AVEDs are best suited for this purpose. Unlike other research techniques, AVEDs have been the recipients of considerable attention from the media. Obviously, a video clipping of a creature in its natural habitat has much greater appeal than a list of dull figures (Moll, Millspaugh, Beringer, Sartwell, & He, A new ‘view’ of ecology and conservation through animal-borne video systems, December 2007). AVEDs are crucial in behavioral research, physiological experiments and conservation. They procure information from the animal’s perspective. AVED research is still to be employed on a large scale. However, the day is not far off, when this will happen. As such, AVEDs provide a number of opportunities for conducting research. Public policy will have to ensure that this technology is used to a much greater extent and that the scientists have better access to it (Moll, Millspaugh, Beringer, Sartwell, & He, A new ‘view’ of ecology and conservation through animal-borne video systems, December 2007). The equipment used in tracking animals has changed considerably. In 1970s; bulky equipment consisting of large and heavy collars fitted with radio frequency transmitters, was used. Now, tiny cameras and global positioning systems, with greater accuracy are being used. These systems have provided vast knowledge regarding the use of animal habitats. The Crittercam, in addition, to capturing audio and video, it also records data relating to velocity and acceleration of the creature, strength of magnetic fields, light levels, depth and temperature. The benefits in using this gadget are that it is small and does not require human interference in studying animal behavior. The world from the perspective of a creature of the wild is engrossing and mankind has seen fascinating images recorded by devices attached to sperm whales, sharks, seals, sea lions, manatees and penguins. In the year 2002, a Crittercam designed for land use was attached to a wild African lion, and this provided a new vista in research on animal borne imaging. Crittercam technology has made it easier to reach unexpected areas of animal life. It has made it possible to make visual records of animal behavior and habitat that no human can do. This new technology has changed into reality, what had previously been in the realm of science fiction. Positron Emission Tomography (PET) One of the different forms of nuclear medicine imaging is known as Positron Emission Tomography (PET). This process employs radiotracers or radioactive material to generate imaging scans. Small quantities of suitable radioactive material are introduced into the body, in a manner that allows its accumulation in the area to be examined. The emitted positrons are detected by a PET scanner that is connected to a computer. The latter measures and produces images that display the structure and function of organs and tissues (Positron Emission Tomography , 2008). There is a significant amount of developmental delay and mental retardation. This has been attributed to gene mutations; and PET, due to its capability to identify the physiological and biochemical outcomes of such mutations, is of considerable importance. A proper understanding of such mutations or polymorphism is indispensable for formulating interventions that would circumvent the abnormal development of the brain (Sundaram, Chugani, & Chugani, 2005). PET has been successfully employed to describe the biochemical changes that take place during the development of the brain. Moreover, it has proved to be of immense help in studying the brain glucose metabolism in the Rett syndrome, synthesis of serotonin in autism, and the study of GABAA receptors in the Prader – Willi and Angelman syndromes (Sundaram, Chugani, & Chugani, 2005). The result of mental retardation is permanent disability; hence, any procedure that could disclose new methods of treatment is always welcome. PET has the capacity to examine the biological basis of mental retardation. Hence, it has the latent ability to unearth new methods of treatment for this ailment (Sundaram, Chugani, & Chugani, 2005). PET is useful in not only in respect of the brain, but also for detecting malfunctions of the heart, presence of epileptic foci and organs that are turning cancerous. It has proved its usefulness, not only in scanning specific areas of the body, but also the whole body. Thus, the PET technology also constitutes a powerful technique of neuroscience (Dumit, 2003. P.4). Positron Emission Tomography or the PET is a new imaging process that records molecular activity. Most of the investigations conducted with PET are related to drugs and their effects. As such, PET and pharmaceutical scientists are closely associated with each other. This relationship is mainly based on the development of molecules and disease, which constitutes their target. Scientists use these molecules in lesser quantities to investigate the biological activity of a target. When these molecules are in high – masses, they play the role of a drug to alter or terminate the target (Phelps, 2002, P 303). PET is capable of examining the pharmacokinetics and bio-distribution of drugs in living mammals. This is a significant relationship between PET and pharmacology. Molecular imaging probes are conducted with less – mass amounts. This helps in the safe examination of the effects and properties of drugs. Near mass less amounts do not have any effect on the biological systems of the human body (Phelps, 2002, P 303). PET imaging probes also act as surrogate markers. These markers help in the examination of the effectiveness of drugs on metabolism and DNA replication. There are three main technical components in PET. These are PET scanner, cyclotron based electronic generators, and biological assays. Cyclotrons are used to produce labeled probes and biological assays employ tracer principles. PET is a molecular imaging technology. Through labeled molecules, the PET makes images of the effects produced by these molecules on the biological processes such as metabolism and DNA replications (Phelps, 2002, P 303). This process is similar to what the pharmaceutical sciences do to produce therapy interactions with molecules. In case of in vivo imaging of molecular interactions with the targets of molecules, the PET is highly sensitive. This can be witnessed in molecular targets with high concentrations of Pico or Femto moles per gram of tissue. However, in those imaging processes the probes by molecules will be limited to a single target, and would employ one to four steps in the biochemical reactions of assays (Phelps, 2002, P 303). Under such circumstances, biochemistry and pharmaceutical science combine to provide a platform for the PET’s molecular probes. Diseases are biological processes. In such processes, the errors and defects in molecules modify the function of cells. Heredity molecular errors are identified easily by sampling cells. However, diseases are the results of modified or failed cell systems in specific organs. Moreover, in hereditary diseases, all cells will have genetic errors. In diseases, the expression of genes is subjected to modification and such modification will be organ – specific, in most of the cases. Therefore, the study of molecules or molecular imaging technologies provides the best basis to identify, analyze and diagnose the biological traits of disease. Ultimately, this helps in rectifying such molecular errors (Phelps, 2002, P 303). This system consists of ingestion of radioactive material, with a short half-life. The positrons emitted by this radioactive material are annihilated on coming into contact with electrons in the body. The resultant pulses of energy and background noise is subjected to sophisticated analysis, which provides better insight into the condition of a particular organ or area of the human or animal body. Oncology has benefitted tremendously, because of developments in PET technology. These developments have been complemented with developments in computer application software and novel scintillators. The future of this technology is promising and could have a major impact on a number of diseases. Conclusion In this manner, two technologies have been put to unexpected use. Crittercams have proved to be extremely beneficial in protecting aquatic and terrestrial species. Some of these creatures had been threatened with extinction. The chief problem faced by scientists had been that there was insufficient knowledge about the habitat and manner in which these creatures lived. These problems have been resolved to a major extent. Similarly, Positron Emission Tomography has provided a non – invasive and early detection of disease or abnormality tool. Many disorders and diseases can be either controlled or cured, if detected in the early stages and it is from this perspective that PET proves its unique advantages. List of References Berger, R. (03/26/2001, P 20). Terrestrial Crittercam. Electronic Media , Vol. 20, Iss, 13 (AN 4324373). Dumit, J. (2003. P.4). Picturing Personhood: Brain Scans and Biomedical Identity (In-formation). Princeton University Press. ISBN-10: 0691113971 . Haraway, D. J. (2007, Pp 258-259). When species meet. Minnesota Press, ISBN: 0816650454, 9780816650453. Moll, R. J., Millspaugh, J. J., Beringer, J., Sartwell, J., & He, Z. (December 2007). A new ‘view’ of ecology and conservation through animal-borne video systems. Trends in Ecology & Evolution , Vol.22, Issue 12, Pp.660-668. Moll, R. J., Millspaugh, J. J., Beringer, J., Sartwell, J., He, Z., Eggert, J. A., et al. (May 2009). A terrestrial animal-borne video system for large mammals. Computers and Electronics in Agriculture , Vol.66, Issue 2,Pp.133-139. Phelps, M. E. (2002, P 303). Molecular Imaging with Positron Emission Tomography. Annual Review of Nuclear & Particle Science , Vol 52, Iss 1 (AN 9688522). Positron Emission Tomography . (2008, September 11). Retrieved May 23, 2009, from RadiologyInfo: http://www.radiologyinfo.org/en/info.cfm?PG=pet Sundaram, S. K., Chugani, H. T., & Chugani, D. C. (2005). Positron emission tomography methods with potential for increased understanding of mental retardation and developmental disabilities. Mental Retardation & Developmental Disabilities Research Reviews , Vol. 11, Issue 4, Pp325-330 (AN 18659520). Wichlegren, I. (10/23/98, P 8). StevenSealberg Directs. Current Science , Vol. 84, Iss 4 (AN 1207667). Read More