A Biometric Fingerprint Scanner With a Locking Mechanism

The purpose of this capstone project was to design, construct, and test a biometric fingerprint locking system to control access to a set of lockers. This system offers a convenient alternative to traditional locks and makes lockers easier to use. Traditional locks require some type of prior knowledge, like remembering the numbers and how to enter them for a combination lock. This can make it difficult and annoying to try and use a simple locker. Three main considerations were kept in mind during the design process to make this system more convenient than traditional locks: user friendliness, accuracy of identification, and false positive rate. The most important aspect of this project was to make a user friendly system, without challenges and questions. It was also vital to have a high identification rate while the false positive rate should be kept to a minimum, as people should not be “accidentally” granted access to other’s lockers. To solve this problem, the project was based around a fingerprint scanner which was controlled by a microcontroller. The microcontroller was the brain of the system. It sends instructions to the fingerprint scanner, interprets returned data, and controls a LCD display so that the system was more user friendly. This report will discuss the background information needed to comprehend a fingerprint identification system, a detailed explanation of the design requirements, the design alternatives along with why components were selected, the preliminary proposed design, and the design of the final prototype

The Dietary Bioaccumulation and Detection of Engineered Nanosilver in Fish

Published in part as: Clark, N. J., Boyle, D. and Handy, R. D. (2019). An assessment of the Dietary Bioavailability of Silver Nanomaterials in Rainbow Trout Using an Ex Vivo Gut Sac Technique. Environmental Science: Nano. 6, 646-660. DOI: https://doi.org/10.1039/C8EN00981C Clark, N. J., Boyle, D., Eynon, B. P. and Handy, R. D. (2019). Dietary exposure to silver nitrate compared to two forms of silver nanoparticles in rainbow trout: bioaccumulation potential with minimal physiological effects. Environmental Science: Nano. 6, 1393-1405. DOI: https://doi.org/10.1039/C9EN00261HEmbargo extended to 24.07.21. Approved by DC. LW 01.06.20Emerging contaminants, including engineered nanomaterials (ENMs), need to undergo environmental risk assessment, whereby they are tested for properties of persistence in the environment, toxicity or bioaccumulation. To date, little data exists for the bioaccumulation of ENMs in animals, particularly fish, with a focus on alternative methods to in vivo testing. Also, interpretation of data for hazard assessment is hampered by the lack of routine methods to detect the form of materials in the tissues following exposure. Therefore, there were three main aims to the thesis; the first was to determine the dietary accumulation of ENMs into fish, using a tiered testing approach. The first step was using a short term (4 h) gut sac technique to demonstrate the bioavailability of Ag materials, using pristine (Ag NPs) and aged (Ag2S NPs) materials. The order of total Ag accumulation was AgNO3 > Ag NPs = Ag2S NPs; in the mid intestine muscularis, there was 457 ± 111, 38 ± 8 and 39 ± 20 ng/g, respectively. The next step in the testing strategy was an in vivo exposure, whereby fish were fed diet containing 100 mg Ag/kg for 4 weeks. Following this, the liver was the main organ of accumulation for all materials, with 4 weeks of exposure leading to concentrations of 122 ± 10, 129 ± 17 and 11 ± 1 µg/g in the AgNO3, Ag NPs and Ag2S NPs, respectively. The order of bioaccumulation was AgNO3 = Ag NPs > Ag2S NPs. Various gut transformations (e.g. dissolution) may have been responsible for the similarity of the AgNO3 and Ag NP treatments, and differences between order in the short term gut sac experiment. The second aim was to develop a method of determining the form of the material in the tissues (particulate versus dissolved). A method was developed using the pristine Ag NPs, whereby a series of potential extractants were used. The only suitable extraction method was tetramethylammonium hydroxide + 5 mM CaCl2, and was verified by extracting Ag as AgNO3 and Ag NPs from gut sac tissues without any change to the form of Ag. When this method was applied to in vivo samples (as above), it showed 83 ± 20, 73 ± 17 and 5 ± 2 x109 particles/g dw in the liver of AgNO3, Ag NPs and Ag2S NP, respectively. Particles were also found in the hind intestine and kidney. The presence of particles in the AgNO3 treatment support the idea that nano-sized particles can be synthesised in the gut lumen or gut tissue, and subsequently transported around the body to the liver. The third aim of this work was to compare rodent gut accumulation with fish, in an exploratory attempt to determine whether rodent bioaccumulation testing can be replaced by fish. This utilised the gut sac technique (as above for fish) in Wistar rats. The total Ag tissue concentrations were higher in the rat (2514 ± 267, 907 ± 284, 1482 ± 668 ng/g in the AgNO3, Ag NPs and Ag2S NPs, respectively), but showed the same accumulation profile of AgNO3 > Ag NPs > Ag2S NPs as in fish. One species difference was transepithelial accumulation was shown in the rat, but not in fish. In conclusion, the ex vivo gut sac technique with adequate characterisation information, could predict the pattern of in vivo bioaccumulation of the Ag materials used here. Particles were present in the hind intestine, liver and kidney of all Ag treatments following dietary exposure, and to a lesser extent in the Ag2S NP treatment, indicating ENM chemistry has an important role in bioavailability. Finally, the rat gut sac experiment did not produce the same data as the fish gut sac experiment, but shows the current risk assessment of dissolved Ag will cover Ag ENMs

Hydrogen silsesquioxane (HSQ) for use in nano imprint lithography

Innovations are being researched, using materials science, in the areas of sub- 100nm feature production. Current methods such as electron beam lithography (EBL), Extreme Ultra-Violet Lithography (EUV), and Nano-imprint lithography (NIL) are currently being studied to deliver a high throughput, low-cost process, and high field size for nano-lithography. EBL is a technique which can generate very small features (sub-10nm) but is a serial process which has undesirable time constraints. EUV is the latest generation of photo-lithography which can produce 35nm features, but has a limited area of exposure. NIL is a high resolution high throughput process, but still has time constraints with imprinter fabrication and pattern predictability. Important aspects of NIL are the creation of imprinters and the anti-adhesive layers used to protect the imprinters. Hydrogen silsesquioxane (HSQ) is a spin on dielectric with properties of a negative e-beam resist which can generate a SiO2 like material. This can then be used as an imprinter for NIL work with significant process advantages over the standard technique for fabricating imprinters. HSQ has been observed to also have a time dependency factor during the electron beam process. For NIL to work effectively anti-stick layers are needed to ensure the correct designs are imprinted. Anti-stick layers such as F13, and Nanonex create a monolayer of atoms designed to reduce the effects of surface bonding on the nano-scale

Development of a suitable detection method for silver nanoparticles in fish tissue using single particle ICP-MS

A strong alkali extraction technique and suitable single particle ICP-MS method is described for the routine quantifying of particle number concentration, particle size and particle mass concentration for silver nanomaterials in fish tissue.</p

Evolution of oceanic margins : rifting in the Gulf of California and sediment diapirism and mantle hydration during subduction

Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2013.Cataloged from PDF version of thesis.Includes bibliographical references.This thesis investigates three processes that control the evolution of oceanic margins. Chapter 2 presents seismic images of a ~2-km-thick evaporite body in Guaymas Basin, central Gulf of California. In rifts, evaporites form under conditions unique to the latest stages of continental rupture, and the presence, age, thickness, and shape place new constraints on the history of early rifting there. Chapter 3 presents numerical experiments that show that diapirs can form in sediments on the down-going plate in subduction zones and rise into the mantle wedge, delivering the sedimentary component widely observed in arc magmas. Chapter 4 presents measurements of seismic anisotropy from wide-angle, active-source data from the Middle America Trench that address the hypothesis that the upper mantle is hydrated by seawater flowing along outer-rise normal faults. These measurements indicate that the upper mantle is ~1.57 to 6.89% anisotropic, and this anisotropy can be attributed to bending-related faulting and an inherited mantle fabric. Accounting for anisotropy reduces previous estimates for the amount of water stored in the upper mantle of the down-going plate from ~2.5 to 1.5 wt%, a significant change in subduction zone water budgets.by Nathaniel Clark Miller.Ph.D

Philosophical Influences in The Art of War found in The Romance of the Three Kingdoms

“Philosophical Influences in The Art of Warfound in The Romance of the Three Kingdoms” is an examination of Sunzi’s philosophy about leadership in The Art of War as applied to the moral character, or lack thereof, of historical Han Dynasty leaders, Liu Bei and Cao Cao. In Luo Guanzhong’s The Romance of the Three Kingdoms, the two are fictionalized with oppositional personalities and corresponding philosophical bases. I explore the ways in which their actions embody or reject the philosophy found in Sunzi’s The Art of War

Parent-Child Similarities in Dental Caries Rates

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68159/2/10.1177_00220345760550062301.pd