A SEMINAR REPORT ON DATA STORAGE ON FINGERNAIL
BY
IMOLOAME TEMITOPE ISIMEME
MAT NO: BAS/CSC/120215
FACULTY OF BASIC AND APPLIED SCIENCES, DEPARTMENT OF MATHEMATICS AND COMPUTER SCIENCE BENSON IDAHOSA UNIVERSITY, BENIN CITY – NIGERIA NIGERIA
NOVERMBER, 2015
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A SEMINAR REPORT ON DATA STORAGE ON FINGERNAIL
BY
IMOLOAME TEMITOPE ISIMEME
MAT NO: BAS/CSC/120215
BEING A SEMINAR WORK SUBMITTED TO THE DEPARTMENT OF MATHEMATICS AND COMPUTER SCIENCE FACULTY OF BASIC AND APPLIED SCIENCES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE AWARD OF BACHELOR OF SCIENCE (B.SC) DEGREE IN COMPUTER SCIENCE, BENSON IDAHOSA UNIVERSITY, BENIN CITY – NIGERIA
NOVERMBER, 2015
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ACKNOWLEDGEMENTS
I give God thanks for granting me the abundant grace to write and present this seminar paper. I am grateful to my seminar supervisor, Mrs I.A Inyang I for her guidance and support during the writing of this seminar paper. I also acknowledge the Head of the Department of Mathematics and Computer Science, Dr. K. Obahiagbon, and the respected lecturers of the same department, Mr. I. Eraikhuemen, Mr. W. Osazuwa, Mr. A.E. Odion, Mrs. J. Ataha and Mr. O. Enagboma for their warm support. I am also thankful to my family, friends and mates for their support at all times towards the successful completion of this seminar paper.
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CHAPTER ONE INTRODUCTION 1.1 BACKGROUND OF THE STUDY
A storage device may hold information, process information, or both. A device that only holds information is a recording medium. Devices that process information (data storage equipment) may either access a separate portable (removable) recording medium or a permanent component to store or retrieve data. Electronic data storage requires electrical power to store and retrieve that data. Most storage devices that do not require vision and a brain to read data fall into this category. Electromagnetic data may be stored in either an analog data or digital data format on a variety of media. This type of data is considered to be electronically encoded data, whether it is electronically stored in a semiconductor device, for it is certain that a semiconductor device was used to record it on its medium. Most electronically processed data storage media (including some forms of computer data storage) are considered permanent (non-volatile) storage, that is, the data will remain stored when power is removed from the device. In contrast, most electronically stored information within most types of semiconductor (computer chips) microcircuits are volatile memory, for it vanishes if power is removed. Except for barcodes and OCR data, electronic data storage is easier to revise and may be more cost effective than alternative methods due to smaller physical space requirements and the ease of replacing (rewriting) data on the same medium. However, the durability of methods such as printed data is still superior to that of most electronic storage media. The durability limitations may be overcome with the ease of duplicating (backing-up) electronic data.
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Devices that are not used exclusively for recording such as hands, mouths, musical instruments, and devices that are intermediate the storing/retrieving process, like eyes, ears, cameras, scanners, microphones, speakers, monitors, or video projectors, are generally not considered storage devices. Devices that are exclusively for recording such as printers, exclusively for reading, like barcode readers, or devices that process only one form of information, like phonographs may or may not be considered storage devices Recently, there have been rapid developments in the field of information technology, resulting in the need to generate, store, and transport a large amount of information while ensuring data security, an important issue in today's digital age. To meet future demands in information technology, femtosecond laser pulse processing offers a powerful tool for developing new highcapacity devices because it allows fabrication of three-dimensional (3-D) structures inside a wide range of transparent materials. In particular, multilayered 3-D optical bit recording is a promising technique for next-generation computing systems because it offers a large recording capacity by stacking many recording layers without increasing the recording density per layer.
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1.2
AIM AND OBJECTIVES OF THE STUDY
Our goal is to realize optical data storage in human fingernail for highly secure data transportation that does not suffer from problems such as theft, forgery, or loss of recording media The objectives of this seminar work are as follows; a. To realize optical data storage in a human fingernail for highly secure data transportation that does not suffer from problems such as theft, forgery, or loss of recording media. b. To demonstrate how to use a femtosecond laser system to write the data into the nail and a fluorescence microscope to read it out. c. To suggest possible ways or method of improving the technology
1.3 SIGNIFICANCE OF THE STUDY
This study will be of great benefits to the world especially in the computer science and engineering field as it will provide the system process of storing data on fingernail. This research work will also suggest some possible ways to improve on the previous technology and it will serve as research material for further research work.
1.4
DEFINITION OF TERMS
Data: Data is distinct pieces of information, usually formatted in a special wa y.
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Data storage: Data storage is a general term for archiving data in electromagnetic or other forms
for use by a computer or device. Different types of data storage play different roles in a computing environment. DNA: Deoxyribonucleic acid is a molecule that carries most of the genetic instructions used in
the development, functioning and reproduction of all known living organisms and many viruses. Fingernail storage: this is a method of writing data onto a human fingernail using a
pulsed laser. Femtosecond laser: this is a laser which emits optical pulses with a duration well be low 1 ps (→
ultrashort pulses), i.e., in the domain of femtoseconds (1 fs = 10−15 s). It thus also belongs to the category of ultrafast lasers or ultrashort pulse lasers. Fluorescence microscope: this is an optical microscope that uses fluorescence and
phosphorescence instead of, or in addition to, reflection and absorption to study properties of organic or inorganic substances. Fluorescence: this is the emission of light by a substance that has absorbed light or other
electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation.
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CHAPTER TWO LITERATURE REVIEW
As technology and science develop, new and more advanced means of storing data are discovered. However, up until know, nobody thought of using the human body as a storage media. According to Nova in 2013, It might be possible to encode data temporarily into regions of skin tissue. This could be accomplished using micro-tattooing technology, or perhaps by “dying” the tissue with a memory-bearing dye, perhaps one that is infused with micro-crystalline storage particles of some sort. This would be a very fragile and temporary way to store data however as skin cells are constantly regenerating, sloughing off, and getting affected by environmental conditions. It might be possible to integrate nanotechnologies into the human body in a manner that could provide integrated digital storage without harming the body itself. For example, suppose there were a way to take a pill that contained nanocrystals encoded with particular data that you wanted to “store.” This pill would be digested and the nanocrystals might be then distributed
throughout the bloodstream for some period of time until they were naturally excreted by the body. (Nova, 2012) Artificial Memory Implants. Of course, rather than modifying the biological substances of the body it might be simpler to just implant a memory-bearing device under the skin. This is similar to current work on implantable RFID chips. The advantage is that such devices may provide a large volume of digital storage in the future, and could potentially be written to and read from remotely using RFID technology. 8
Spivack in 2015,stated that DNA provides an excellent medium for data-storage; particularly the junk DNA regions which presumably are less involved in critical functions of the DNA (although recent evidence supports the hypothesis that so-called “junk DNA” may be more involved in cell specialization than was previously thought). Storing data in DNA has the advantage that data is distributed throughout the entire body. Furthermore, if stored in the sexcells, stored data can be passed down to offspring. A disadvantage of using DNA for datastorage is the possible unanticipated effects on cell development and health.( Spivack, 2015) The DNA technology uses artificial DNA made using commercially available oligonucleotide synthesis machines for storage and DNA sequencing machines for retrieval. This type of storage system is more compact than current magnetic tape or hard drive storage systems due to the data density of the DNA. It also has the capability for longevity, as long as the DNA is held in cold, dry and dark conditions, as is shown by the study of woolly mammoth DNA from up to 60,000 years ago, and for resistance to obsolescence, as DNA is a universal and fundamental data storage mechanism in biology. These features have led to researchers involved in their development to call this method of data storage "apocalypse-proof" because "after a hypothetical global disaster, future generations might eventually find the stores and be able to read them." It is, however, a slow process, as the DNA needs to be sequenced in order to retrieve the data, and so the method is intended for uses with a low access rate such as long-term archival of large amounts of scientific data. (Goldman, et al 2013)
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The idea and the general considerations about the possibility of recording, storage and retrieval of information on DNA molecules were originally made by Mikhail Neiman and published in 1964 – 65 in the Radiotekhnika journal, USSR, and the technology may therefore be referred to as MNeimON (Mikhail Neiman OligoNucleotides). The journal Science published research by George Church and colleagues at Harvard University, in which DNA was encoded with digital information that included an HTML draft of a 53,400 word book written by the lead researcher, eleven JPG images and one JavaScript program. Multiple copies for redundancy were added and 5.5 petabits can be stored in each cubic millimeter of DNA. The researchers used a simple code where bits were mapped one-to-one with bases, which had the shortcoming that it led to long runs of the same base, the sequencing of which is error-prone. This research result showed that besides its other functions, DNA can also be another type of storage medium such as hard drives and magnetic tapes. (Yong, 2013) An improved system was reported in the journal Nature in January 2013, in an article lead by researchers from the European Bioinformatics Institute (EBI) and submitted at around the same time as the paper of Church and colleagues. Over five million bits of data, appearing as a speck of dust to researchers, and consisting of text files and audio files, were successfully stored and then perfectly retrieved and reproduced. Encoded information consisted of all 154 of Shakespeare's sonnets, a twenty-six-second audio clip of the "I Have a Dream" speech by Martin Luther King, the well known paper on the structure of DNA by James Watson and Francis Crick, a photograph of EBI headquarters in Hinxton, United Kingdom, and a file describing the methods behind converting the data. All the DNA files reproduced the information between 99.99% and 100% accuracy. The main innovations in this research were the use of an errorcorrecting encoding scheme to ensure the extremely low data-loss rate, as well as the idea of 10
encoding the data in a series of overlapping short oligonucleotides identifiable through a sequence-based indexing scheme. Also, the sequences of the individual strands of DNA overlapped in such a way that each region of data was repeated four times to avoid errors. Two of these four strands were constructed backwards, also with the goal of eliminating errors. The costs per megabyte were estimated at $12,400 to encode data and $220 for retrieval. However, it was noted that the exponential decrease in DNA synthesis and sequencing costs, if it continues into the future, should make the technology cost-effective for long-term data storage within about ten years. (Grass, 2015) The long-term stability of data encoded in DNA was reported in February 2015, in an article by researches from ETH Zurich. By adding redundancy via Reed – Solomon error correction coding and by encapsulating the DNA within silica glass spheres via Sol-gel chemistry, the researchers predict error-free information recovery after up to 1 million years at -18 °C and 2000 years if stored at 10 °C. By adding the possibility of being able to handle errors, the research team could reduce the cost of DNA synthesis down to ~$500/MB by choosing a more error-prone DNA synthesis method. In a news article in the New Scientist the team stated that if they are able to further decrease the cost they would store an archive version of wikipedia in DNA. (Jacobs, 2015) Benign viruses as storage media. An interesting possibility might be to create a benign virus that could be used to carry stored data. This virus would have to be non-transmittable and have no adverse effects on health, functionality and well-being of the host organism. Data could be encoded onto specimens of this virus and then injected, ingested or inhaled to “store” it in the
human body. Later, the data could be retrieved via a small sample of blood containing the virus. Ideally, this virus could be tagged genetically such that differently tagged viruses could be 11
identified and used to store different data. Data would never have to be erased instead a new tagged virus would be created containing the new data and would simply supersede the previous virus. One potential issue is immune-response to the virus however, which could cause the body to attack it and result in lost data. Another potential concern would be viral mutation, and the possible effects on data and on health that could result. (Spivack 2012) According to Jacqueline Hewett for Yoshio Hayasaki of Tokushima University and colleagues have discovered that data can be written into a human fingernail by irradiating it with femtosecond laser pulses. Capacities are said to be up to 5 megabits and the stored data lasts 6 months, which is the length of time it takes a fingernail to be completely replaced. Data stored in a fingernail can be used with biometrics, such as fingerprint authentication and intravenous authentication of the finger. Storing messages in DNA it might be interesting to explore ways to encode large volumes of data directly into parts of the human body. Storing data in DNA has the advantage that data is distributed throughout the entire body. Furthermore, if stored in the sex-cells, stored data can be passed down to offspring. A disadvantage of using DNA for data-storage is the possible unanticipated effects on cell development and health. Messing with DNA is risky it may be safer to store data in other parts of the human body (with the one potential disadvantage that such data would not be passed down via heredity).Storing data on fingernails is a safe process. Using this technology we save our data without having its bad effect on body. Thus it is a safer process as compared to DNA storage. Some suggestions for parts of the human body that might be good media for data-storage.
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depth is determined by microscope observation of the sample surface. When the focusing position is inside the sample, Z is positive. The irradiation pulse energy E p described in this paper is the product of the energy measured at the entrance of the microscope and the transmittance of the microscope system, including transmittance of the objective. The transmittance of the microscope is 0.49. The sample is a small piece of human fingernail whose size is about 2×2×0.4 mm3, and its surface is polished with abrasive lapping films (#1000~#10000). The surface polish reduces the required pulse energy for processing because the scattering and the distortion of the wavefront are decreased.
Fig.2.1 Femtosecond laser processing system. Source: http://www.novaspivack.com/science/dnadata.
When the femtosecond laser pulse is focused inside a material, molecules are subjected to multi photon ionization and optical field ionization at a local volume where the laser pulse is focused. Consequently, the ionized molecules repulse each other, and a micro explosion occurs, which causes a structural change in the material. Figure2.2 shows transmission-illumination microscope observations of three bit arrays recorded inside a human fingernail. These bit arrays were 13
Fig.2.2. Multilayered bit arrays Source: http://www. novaspivack.com
Fig2.3. The pulse was irradiated from the upper side Source: : http://www. novaspivack.com
Side view of the structures formed in a human fingernail with (a) E p =0.25 µJ, (b) E p=0.49 µJ, (c) E p =0.98 µJ, (d) E p =2.0 µJ, and (e) E p =3.9 µJ. The scale bar indicates 10 µm. The figure is made of two images that were obtained with adjusting the observation focus to the structures in each images. 14
CHAPTER THREE 3.1.1 HOW DATA IS STORED ON FINGERNAILS
There is an increase in fluorescence intensity compared with the surrounding auto-fluorescence intensity at a structural change produced by a focused femtosecond laser pulse inside a human fingernail. The spectrum of the increased fluorescence coincides with the auto-fluorescence spectrum of a fingernail and that of pure keratin. The increased fluorescence intensity is also observed in a heated fingernail. It is suggested that the increased fluorescence is a result of a local denaturation of keratin protein caused by the femtosecond laser pulse irradiation. The increased fluorescence effect is very useful for reading out the bit data recorded inside a human fingernail. We also demonstrate that three-dimensionally-arranged structural changes can be read out with little cross-talk by making use of the increased fluorescence. Furthermore, we demonstrate that fluorescence can be observed for up to 6 months, corresponding to the time required for a fingernail to grow from root to tip. DATA STORING ON NAILS When the femtosecond laser pulse is focused inside a material, molecules are subjected to multi photon ionization and optical field ionization at a local volume where the laser pulse is focused. Consequently, the ionized molecules repulse each other, and a microexplosion occurs, which causes a structural change in the material. Figure 2 shows transmission-illumination microscope observations of three bit arrays recorded inside a human fingernail. By changing the value of Ep data at various layers are stored. The laser ionizes the photon and these photon carry data.
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CHAPTER FOUR SUMMARY CONCLUSION AND RECOMMENDATIONS
4.1 SUMMARY
Conclusion
We have demonstrated an increased fluorescence intensity at the structural change inside a human fingernail produced by a focused femtosecond laser pulse. The fluorescence intensity was higher than the surrounding auto-fluorescence intensity of the fingernail. The structural changes, whose geometrical shape drastically depends on the irradiated pulse energy, are observed as a dark region by using a microscope with transmission illumination. The increased fluorescence intensity was observed in the dark region. The spectrum of the increased fluorescence coincided with the auto-fluorescence spectra of the fingernail. The increased fluorescence intensity was also observed in a fingernail heated in a drying oven. It is suggested that the increased fluorescence of the structure is a result of a local denaturat ion the keratin protein caused by heat generated by the femtosecond laser pulse irradiation.
We demonstrated that the increased fluorescence of the structure is useful for reading out threedimensionally recorded data inside a human fingernail. We recorded three bit planes inside a human fingernail. We demonstrated that three bit planes can be read out with little cross-talk by using fluorescence readout. Furthermore, we demonstrated that fluorescence can be observed for
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up to 6 months, corresponding to the time required for a nail to grow from root to tip. Under these recording conditions, a recording density of 2 Gbit/cm3 is achievable.
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