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In this episode, we visit some ancient Sumerians so we can expand our view of finger counting and see how this applies to counting with transistors. From this, we will have the basis for unsigned binary integers and the humble binary digit or bit. We also show how to calculate the upper limit to which a fixed number of transistors can count.

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Finger movements in the sagittal plane mainly consist of flexion and extension about the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. The purpose of this study was to develop a biomedical finger model and to validate it by comparing finger strength and muscular forces in static exertions, which predicated from the model and measured in experiments. Two kinematic finger models were developed: one was with the assumption of constant tendon moment arms, and the other was with the assumption of non-constant tendon moment arms. Equations of static equilibrium were derived for these finger models using the principle of virtual work. Equations of static equilibrium for the finger models were indeterminate since only three equations were available for five unknown variables (forces). By reducing the number of variables based on information in the literature on muscular activities in finger movements, the amounts of force which muscles exerted to maintain static equilibrium against an external load were computed from the equilibrium equations. The muscular forces were expressed mathematically as functions of finger positions, tendon moment arms, lengths of phalanges, and the magnitude and direction of external load. Equations of muscular forces were used to predict external finger strength and to compute internal muscular forces in static exertions against an external load. Computer simulations were performed to compute finger strengths and muscular forces at various finger positions and directions of force exertions. For this, finger positions were controlled, and lengths of phalanges were measured. Experiments were performed to measure finger strengths and muscular activity levels in submaximal contractions. Muscular activity levels were estimated by ratios of standardized EMG amplitude to exerted force. Measurements were taken in combinations of four finger positions and four directions of force exertions. Validation of the biomechanical finger models was done by comparing the results of computer simulations and experiments. Significant differences were found between the predicted and measured finger strengths. However, the trends of finger strengths with respect to finger positions were similar in both the predicted and measured. Trends of variations in predicted and measured muscular activity levels were not different from each other. These findings indicate that the finger models and the procedure to predict finger strengths and muscular forces were correctly developed. / Ph. D.

Data collection on isometric forces exerted by means of the digits, is a virtually untapped research area. However, such data would prove particularly useful in areas such as hand-tool and control design, and also in medical evaluation. A standardized protocol is necessary if a sound, useful data base is to be built. This study developed such a protocol and data were collected using the defined protocol. The study also showed that occupational level (defined by tools and controls used) and gender both had significant effects on certain strength exertions of the digits. Therefore the appropriate data must be collected, depending on the intended use and user population. Regression equations were produced which predicted the strength exertions using anthropometric measurements which are commonly available. Although some particular exertions were not well predicted, the potential of prediction was verified. / Master of Science

published_or_final_version / abstract / toc / Biochemistry / Master / Master of Philosophy

The growing obesity epidemic in America carries with it numerous health risks, including diabetes, increased serum lipid levels, and excess fat accumulation in the liver. If these conditions persist or become exacerbated, they may lead to the development of cardiovascular disease, the current leading cause of death among Americans, or to nonalcoholic fatty liver disease (NAFLD) which can progress to hepatocellular carcinoma (HCC), one of the deadliest forms of cancer. Better understanding of the genes involved in these diseases can lead to improved identification of at-risk individuals and treatment strategies. Our lab previously identified zinc fingers and homeoboxes 2 (Zhx2) as a regulator of hepatic gene expression. The BALB/cJ mouse strain has a hypomorphic mutation in the Zhx2 gene, causing a 95% reduction in Zhx2 protein expression. The near ablation of Zhx2 in BALB/cJ mice confers protection from cardiovascular disease when fed a high fat diet, yet these mice show increased hepatic lipid accumulation and liver damage. Microarray data indicates Zhx2 may be involved in the regulation of numerous genes involved in lipid metabolism. Recent GWAS studies indicate ZHX2 may contribute to the risk of cardiovascular disease and liver damage in humans as well. In this dissertation, I characterize the role of Zhx2 expression in the liver and how it affects the risk of both cardiovascular disease and liver damage. I generated liver-specific Zhx2 knockout mice and confirmed Zhx2 regulates several novel targets that could contribute to the fatty liver phenotype seen in BALB/cJ mice. Further studies revealed that hepatic Zhx2 expression is necessary for proper sex-specific expression of several Cyptochrome P450 (CYP) genes and could contribute to gender differences in disease susceptibility. Lastly, I performed studies into the functional role of the Zhx2 target gene Elovl3. A mouse model of HCC revealed that Elovl3 is completely repressed in HCC tumors. Cell viability and cell cycle assays indicate that Elovl3 expression slows cell proliferation and may be important for proper cell cycle checkpoints. Together, these data indicate that Zhx2 and/or its targets could be clinically relevant in the detection, prevention, or treatment of cardiovascular disease, fatty liver, and HCC.

Gold compounds have been used in medicine dating back as early as 2500 BC. Over the years gold(I) and gold(III) compounds have been used and designed to target rheumatoid arthritis, cancer, and viral diseases. New drug targets have been found for gold compounds that give insight into their mechanisms of action. Here we focus on the synthesis of Au(III) compounds designed to selectively target zinc finger (ZF) proteins. ZF proteins exhibit a variety of functions, including transcription, DNA repair, and apoptosis. Displacement of the central zinc ion, along with mutation of coordinated amino acids can result in a loss of biological function. Synthesis of complexes that selectively target zinc finger proteins, in turn inhibiting DNA/ZF interactions and therefore resulting in loss of protein function, is of great interest. Of particular interest here is the Cys3His (Cys = cysteine, His = histidine) HIV nucleocapsid zinc finger protein, NCp7. NCp7 is involved in multiple steps of the HIV life cycle, thus making it a desirable drug target. Previous studies from our group show platinated nucleobases such as [Pt(dien)(9-EtG)]2+ (dien = diethylenetriamine; 9-EtG = 9-ethylguanine) to stack effectively in a non-covalent manner with tryptophan of the C-terminal finger of HIV Nucleocapsid, NCp7(F2), a key residue involved in nucleic acid recognition. Due to the isoelectronic and isostructural relationship of Au(III) to Pt(II), we have expanded this system to Au(III)-(nucleobase/N-heterocycle) compounds. Novel Au(III)(dien)(N-heterocycle) compounds, including the first Au(III)N3(N-purine) examples, were synthesized. As previously reported for [AuCl(dien)]Cl2, these compounds exhibit pH dependency of the 1H NMR chemical shifts of the dien ligand. The acidity of the dien ligand is affected by the nature of the fourth ligand as a leaving group. The presence of an inert nitrogen donor, compared to that of the more labile Cl-, as the leaving group stabilizes the Au(III) metal center towards reduction, resulting in significant enhancement of π−π stacking interactions with tryptophan relative to platinum(II) and palladium(II) compounds. The presence of a more inert N-donor as the leaving group slows down the reaction with the sulfur-containing amino acid N-Acetylmethionine (N-AcMet); essentially no reaction was observed for the Au(III)-N-heterocycle compounds. All compounds react readily with N-Acetylcysteine (N-AcCys), however lack of N-heterocycle ligand dissociation indicates, to our knowledge, the first long-lived N-heterocycle-Au-S species in solution. Electrospray ionization mass spectrometry (ESI-MS) studies with NCp7(F2) indicate [Au(dien)(DMAP)]3+ (DMAP = 4-dimethylaminopyridine) to be the least reactive of the Au(III) compounds studied, showing the presence of intact NCp7(F2) zinc finger at initial reaction times. Reactivity of the Au-compounds was compared with that of Sp1(F3), a Cys2His2 ZF; in contrast, no intact ZF was observed for any of the compounds studied, suggesting the mode of action of these compounds is dependent on the nature of the zinc binding core. ESI-MS studies were expanded to that of the full HIV NCp7 zinc finger. [Au(dien)(9-EtG)]3+ reacts quickly with NCp7, resulting in immediate zinc ejection and replacement with up to three gold ions. Unlike with [Au(dien)(DMAP)]3+, no intact NCp7 was observed. Addition of [Au(dien)(9-EtG)]3+ to preformed NC-SL2 complex results in release of free RNA; based on EMSA (electrophoretic mobility shift assay) studies, [Au(dien)(9-EtG)]3+ disrupts the NCp7-RNA complex with an IC50 of ~450 µM. It is possible that this HIV nucleocapsid-nucleic acid antagonism may result in a loss of viral activity.

Elucidating patterns of connectivity for species of conservation concern is crucial in the design of networks of ecologically coherent marine protected areas, and therefore is considered in the design of such a network recently proposed to the UK Government. However, data concerning connectivity are deficient for most invertebrate sessile taxa. Therefore, this study used microsatellite panels developed de novo to assess the population genetic structure and genetic connectivity of two temperate octocorals in the North East Atlantic. Microsatellite panels for both species show evidence of cross-species transferability, and therefore in future may prove to be useful monitoring tools for the target species but also for congenerics further afield in Europe. Eunicella verrucosa (O. Alcyonacea: S.O.Holaxonia: F. Gorgoniidae), a threatened and IUCN red-listed sea fan, was sampled in the northerly extremes of its eastern Atlantic range in southern Portugal, Brittany, the South West UK and western Ireland. In this vicinity, connectivity appears to be defined at regional scales and localised cases of inbreeding and differentiation suggest that the population structure of this species is best described as a metapopulation. Alcyonium digitatum (O. Alcyonacea: S.O. Alcyoniina: F. Alcyoniidae), a soft coral, was sampled in the central portion of its range in Brittany, western Ireland, south west UK and the North Sea. This species exhibited very little population structure and apparent panmixia across the sampled range. However, high levels of heterozygote deficiencies and inbreeding in the majority of populations implies that the genetic structure of some populations of this species may be defined by self-seeding and rarer dispersal events that occur sufficiently often to offset divergence via genetic drift. Coalescent analyses indicate that in both species, migration between regions occurs asymmetrically. The presence of few duplicate genotypes in both datasets implies that sexual reproduction predominates in both species in the sampled area. Eunicella verrucosa is a charismatic species that is often used to promote marine conservation efforts in the UK and A. digitatum is a ubiquitous animal around western European coasts; the two species often occur together and both may suffer the damaging effects of mobile fishing gears. This research represents the first population genetic assessment of both species and the first time microsatellites have been used to assess population structure of octocorals in the North East Atlantic.

O objetivo deste trabalho é desenvolver um algoritmo capaz de extrair medidas dos dedos e da palma das mãos. Essas imagens serão adquiridas através de um banco de imagens digitalizadas em um scanner de mesa, facilmente encontrado, e processadas para se obter uma curva do contorno da mão, permitindo assim que se extraia informações biométricas das mesmas. As imagens armazenadas no banco serão então associadas a um determinado usuário, visando em um estágio futuro, aplicações na identificação pessoal. / The object of this work is to develop an algorithm to extract fingers and hands palm measures. Those images will be acquired from a database of images digitalized by a scanner, easily founded, and processed to get the hand contour, allowing biometrics informations to be extracted. The images stored in the database will be associated with an user, aiming personal identification in a future stage.