Stair climbing is a common activity encountered in daily living. Stair ascent is a demanding task that requires a large range of motion of the joints, strong muscle strength, good cardiovascular fitness, and fine balance control. Given this, the activity can be difficult for different populations that lack muscle strength and coordination. To train and assist people in this activity, several robotic platforms have been proposed, but these limit the natural motion of the individual. For example, these devices fix the placement of the feet and reduce the natural swing of the lower limbs. This makes it difficult to manipulate the center of mass, which is crucial to stair ascent. In this dissertation, we present a novel parallel cable-driven platform in which the end effector is the user’s pelvis; the stairmill tethered pelvic assist device. This architecture allows the user to retain their natural movement and relation between the feet and the center of mass, all while applying three dimensional forces on the pelvis during continuous stair ascent on a revolving stairmill. In this work, we show the design, fabrication, and validation of this robotic system. Various force strategies were explored during stairmill ascent using this robotic platform. A characterization experiment was conducted to investigate gait performance and muscle coordination. Two simple interventions were tested to show the potential for long-term training program. This work sheds light on the different strategies of stair climbing and how we can use cable driven platforms to train and assist individuals during this challenging task. The knowledge gained by this work allows for the expansion of designing training paradigms for stair climbing with natural motion. These can assist individuals in improving their quality of life.

Balancing selection maintains advantageous genetic diversity in populations through a variety of mechanisms including overdominance, negative frequency-dependent selection, temporal or spatial variation in selective pressures, and pleiotropy. If environmental pressures are constant through time, balancing selection can affect the evolution of selected loci for millions of years, and its targets might be shared by different species. This thesis is comprised of two different approaches aimed at detecting shared signatures of balancing selection in the genomes of humans and other great apes. In the first part of the thesis, we focus on extreme loci where the action of balancing selection has maintained several coding trans-species polymorphisms in humans, chimpanzees and bonobos. These trSNPs segregate since the common ancestor of the Homo-Pan clade and have survived for ~14 million years of independent evolution. These loci show the characteristic signatures of long-term balancing selection, as they define haplotypes with high genetic diversity that show cluster of sequences by allele rather than by species, and segregate at intermediate allele frequencies. Apart from several trSNPs in the MHC region, we were able to uncover a non-synonymous trSNP in the autoimmune gene LAD1. In the second part of the thesis we explore shared signatures of balancing selection outside trSNPs. We first implement a genome scan designed to detect signatures of balancing selection using NCD2 in the genomes of nine great ape species, including chimpanzee, bonobo, gorilla and orangutan. We show that targets of balancing selection are shared between species that have diverged millions of years ago, and that this observation cannot be explained by shared ancestry. We further demonstrate that targets of balancing selection primarily affect the evolution of genic regions of the genome, although we see evidence for their involvement in the regulation of gene expression. Overall, we provide comprehensive evidence that similar environmental pressures maintain advantageous diversity through the action of balancing selection in humans and other great apes, notwithstanding the deep divergence times between many of these species.

Toxoplasmosis is a zoonotic disease with severe manifestations in HIV-positive human patients. In 1978 the overall sero-prevalence of toxoplasmosis in human patients in South Africa was found to be 20%. Toxoplasmosis in immunocompromised patients is known to be a cause of sometimes fatal complications, such as encephalomyelitis and ocular lesions. According to the literature, mutton infected with the cysts of Toxoplasma gondii is an important route of transmission to humans who ingest under-cooked meat, or eat with unwashed hands after working with meat. There is no data on the sero-prevalence in sheep in South Africa, although this is available for most other countries, including Zimbabwe. The aim of this study was to estimate the sero-prevalence of T.gondii in sheep in South Africa and to discuss the zoonotic aspects related to the prevalence of toxoplasmosis in humans. Three-stage cluster sampling was done where five different provinces randomly chosen from all the provinces in South Africa were the primary units: Gauteng, KwaZulu-Natal, Free State, Eastern Cape and Western Cape. Two sheep abattoirs and one rural location per province, selected randomly from a list supplied by the provincial Departments of Agriculture, were the secondary units. A total of 677 serum samples from these sheep were tested for IgG using the Indirect Fluorescent Antibody (IFA) test (Diagnostic&Technical Services CC, Randburg, South Africa) and the commercial Enzyme-linked Immunosorbent-Assay (ELISA) kit. Informal interviews were conducted with doctors (n=5), doctors regarded as experts (n=17) were selected for an expert opinion survey and National Laboratories (n=3) supplied data on human serum tested for toxoplasmosis in different provinces. The sero-prevalence in sheep, per province, was found to be: Gauteng 6%, Eastern Cape 7.8%, Western Cape 6%, KwaZulu-Natal 6.3% and Free State 2.7% when tested with the IFA test. The results obtained with the ELISA test were: Gauteng 6%, Eastern Cape 5.4%, Western Cape 4%, KwaZulu-Natal 3.6% and Free State 2.7%. Overall prevalences of 5.6% (IFA) and 4.3% (ELISA) were obtained. From the results it appears that toxoplasmosis in sheep has a lower sero-prevalence in South Africa than in other countries. Zimbabwe has an average sero-prevalence in sheep of 67.9%, there is a 80% sero-prevalence in sheep in France and 20-30% in different states in the USA. There was no significant difference between the levels in rural and commercial sheep at the 95% confidence level in South Africa, although there was a significantly higher prevalence in intensively farmed sheep in contrast to those farmed extensively. The informal interviews with the medical doctors indicated that they do not consider toxoplasmosis as an important disease. In contrast to these findings, the experts regard toxoplasmosis as a significant disease and the data obtained from the National Laboratories substantiated this opinion. The seroprevalence in humans was found to be between 14 and 32 % in the three provinces from which data were obtained. It can be concluded that the lower sero-prevalence of toxoplasmosis in sheep in South Africa, as compared with international levels, was probably due to more extensive methods of sheep farming and the relatively low rainfall in southern Africa. It must be noted, however, that comparison of sero- prevalence in different countries is made difficult by the many different tests and end-titres used in both humans and animals. Standardisation is recommended. The presence of toxoplasmosis in sheep in South Africa should be considered as significant because in this country we have a high consumption of mutton. Medical practitioners underestimate the importance of toxoplasmosis in humans. It was recommended that a pamphlet for education of veterinarians, doctors, health workers and patients be produced to increase the knowledge and understanding of this disease and its prevention in South Africa. / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2006. / Paraclinical Sciences / MSc / unrestricted

Energy densities (ED, mJ/mm3) quantify mechanical work imposed on articular cartilages during function. This cross-sectional study examined differences in temporomandibular joint (TMJ) ED during asymmetric versus symmetric jaw closing in healthy females versus males. ED component variables were tested for differences between and within sexes for two types of jaw closing. Seventeen female and 17 male subjects gave informed consent to participate. Diagnostic criteria for temporomandibular disorders and images (magnetic resonance (MR), computed tomography) were used to confirm healthy TMJ status. Numerical modelling predicted TMJ loads (Fnormal) consequent to unilateral canine biting. Dynamic stereometry combined MR imaging and jaw-tracking data to measure ED component variables during 10 trials of each type of jaw closing in each subject's TMJs. These data were then used to calculate TMJ ED during jaw closing asymmetrically and symmetrically. Paired and Student's t tests assessed ED between jaw closing movements and sexes, respectively. Multivariate data analyses assessed ED component variable differences between jaw closing movements and sexes (α = 0.05). Contralateral TMJ ED were 3.6-fold and significantly larger (P <.0001) during asymmetric versus symmetric jaw closing, due to significantly larger (P ≤.001) distances of TMJ stress-field translation in asymmetric versus symmetric movement. During asymmetric jaw closing, contralateral TMJ ED were twofold and significantly larger (P =.036) in females versus males, due to 1.5-fold and significantly smaller (P ≤.010) TMJ disc cartilage volumes under stress fields in females versus males. These results suggest that in healthy individuals, asymmetric compared to symmetric jaw closure in females compared to males has higher TMJ mechanical fatigue liabilities.

Carta al editor / Revisión por pares

This dissertation explored sane effects of context on the development of stimulus classes and the transfer of stimulus functions to novel stimuli. The research was also intended to demonstrate the utility of current behavioral theories for prediction and control of contextual effects on class formation. In Experiment lA, contextual control of stimulus classes was established successfully in all six college-student subjects. Matching-to-sample training successfully transferred the function of the contextual stimuli to four novel stimuli, whim resulted in the formation of two three-member classes of contextual stimuli. The first portion of Experiment 1B replicated Experiment 1A with three additional subjects. In the second portion, matching-to-sample training resulted in the establishment of two six-member contextual classes. In Experiment 2, three of four subjects learned a matching-to-sample task in whim the role of the contextual stimuli was controlled by a pair of ''higher-order'' contextual stimuli. 'Iwo of the subjects received matching-to-sample training in whim the function of the higher-order contextual stimuli was transferred to four novel stimuli, which resulted in the development of two three-member, higher-order contextual classes. Experiments 3A, 3B, and 3C demonstrated that sane groupings of stimuli are more difficult to learn than other groupings. The experiments found that overlapping roles of stimuli tended to confuse subjects and that subjects, when confused, would respond based on "familiarity" to stimuli rather than on the conditional relations. Experiments 4A and 4B demonstrated that types of matching performance (identity, oddity, and arbitrary) can be controlled by the presence of contextual stimuli. The experiments also provided evidence supporting the idea that generalized identity (reflexivity) and generalized oddity performances are closely related to, if not prerequisites for, successful arbitrary matching and the development of stimulus classes.

Transverse radiopaque lines, often referred to as transverse lines (TL's), are a type of hard-tissue pathology which develop in subadult long bones after episodes of nonspecific stress such as nutritional or metabolic insult. This pathology is well documented in archaeological contexts and is used as a tool for making paleo demographical inferences about the general health of populations. Stable isotope studies have suggested that early modern humans were exploiting a wide range of dietary resources by the mid-Upper Paleolithic, while Neandertals appear to have utilized a narrower spectrum of resources, expending more energy on large game. This may have been a significant factor in differential survival success, frequency of transverse line formation, and age of initial transverse line formation. Because archaic humans may have been more susceptible to seasonal resource fluctuations, they may have suffered increased nutritional and metabolic stress compared to early modern humans. This study evaluates differences in the frequency and timing of initial transverse line formation among archaic, early modern human, and recent human (Holocene) subadult populations. Radiographs of the tibial distal shafts of 200 archaic, early modern humans, and recent modern humans were scored as displaying or not displaying TL's. TL's were counted, and age-at-formation was calculated. Kruskal-Wallis nonparametric tests were used to compare the frequency of occurrence of TL's and age-at-formation among the three groups. Results indicate that both archaic and early modern humans exhibited less transverse lines than the recent human group. This may be related to sampling bias in the recent human dataset. There is no difference in the number of transverse lines among the recent human samples, and it seems possible that all three of the recent human populations sampled for this study were experiencing high levels of stress. Thus, it seems that for the archaic and early modern human groups, transverse line formation may have been more closely related to differences in subsistence strategies, while transverse line formation in the recent human group may have been more closely related to high frequencies of metabolic diseases and poor diet. Further analysis revealed that archaic humans developed their first transverse lines earlier in life than both early modern and recent modern humans. The age at first line formation is frequently related to weaning age in studies of archaeological population, and this (and other possible explanations) are evaluated relative to Late Pleistocene Neanderthals and early modern humans.

京都大学 / 新制・論文博士 / 博士(医学) / 乙第13537号 / 論医博第2277号 / 新制||医||1065(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 篠原 隆司, 教授 近藤 玄, 教授 齋藤 潤 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

The thesis describes insects (class insecta) as an important group of organisms living in almost all ecosystems. It investigates the importance of insects for humans not only from a human point of view. First part focuses on the positive impact of insects for humans and their use in many areas of human life, such as agriculture, insect products, forensic entomology, medicine and others. The following part focuses on insect pests, parasites and synanthropic species a human being can encounter during one's life. Next parts describe the possibilities of including insects in lessons at schools; a content analysis of textbooks for elementary schools and high schools from the viewpoint of benefits of insects for humans; and a questionnaire survey of popularity of insects, their breeding and entomophagy focused on pupils of elementary schools. KEYWORDS insects, importance of insects, useful insects, insect pests, insect parasites, types of insects, textbook

A literature review was conducted to evaluate existing knowledge of incivility in the nursing workplace through the lens of nursing ethics and spirituality. Study articles presented a consistent theme of improved organizational commitment and job satisfaction when spirituality was injected into the workplace. It seems plausible to suggest a positive correlation between spirituality and more civil environments in nursing workplaces.