Walking is the most common form of human locomotion and the systematic study thereof is known as gait analysis. Measurement and assessment thereof have application in many fields including clinical diagnosis, rehabilitation and biomechanics. The process of gait evaluation is typically done using an optical motion analysis system combined with stationary force platforms. This is considered the gold standard, but unfortunately, has several drawbacks. It is expensive, requires dedicated laboratories with spatial restrictions, calls for lengthy set up and post-processing times and cannot be used in 'real-world' environments. Alternative systems based on wearable sensors have been developed to overcome these limitations. The Council for Scientific and Industrial Research (CSIR) has therefore developed a prototype wearable sensor unit consisting of an inertial measurement unit (IMU). The objective of the current study is, therefore, to advance the prototype to a wearable multi-sensor system for quantitative gait analysis. The focus is on the development of the pre- and post-processing algorithms and methods used to transform the measurements into interpretable information. The focus outlined includes establishing techniques for synchronising the data from the sensors offline, pre-processing the signals, developing algorithms for stride and gait event detection, selecting an appropriate gait model and defining methods for estimating gait parameters. The determined parameters were the spatio-temporal and joint kinematics (hip, knee and ankle). The algorithms and new system were validated against the Vicon motion capture system through gait analyses. The twenty able-bodied volunteers that took part were required to walk across the laboratory six times at three self-selected walking speeds (slow, normal and fast). For the sake of simplicity and due to various limitations, only data in the sagittal plane of the right lower limb of each volunteer was used to validate the wearable system and associated algorithms. The results obtained were then evaluated against several validation criteria. The absolute mean difference between the estimated timing of detected gait events of the two systems was consistently small (between 0.021 and 7.25% of the gait cycle overall). The spatially dependent parameters, stride length and walking speed, had significant maximum mean absolute percentage errors (31.9 and 34.5% respectively), but with little variation. Excluding outliers, that of the temporal parameters, stride time and cadence, was significantly lower (5.7 and 5.6% respectively). The kinematic results were substantially comparable with a minimum correlation co-efficient of 0.86 and a maximum RMSE of 7.8 degrees with little variation implying repeatability. Although there were some discrepancies between the outputs, the wearable sensor system and its corresponding algorithms were considered feasible and potentially beneficial to developing countries like South Africa. Recommendations for future work include synchronising data between the wearable and reference system for stride-to-stride comparisons and validating algorithms using a known reliable wearable system. / Dissertation (MEng)--University of Pretoria, 2017. / Mechanical and Aeronautical Engineering / MEng / Unrestricted

This study aimed to provide more general knowledge about the mechanisms which link natural resources with civil war outbreaks. The theoretical point of departure was the feasibility hypothesis hypothesis of Collier et al. (2009) in which the authors state that the paramount interest of researchers of civil wars should be directed at the structural conditions within a country. One of their assertions pertained to the role of natural resources. Those provide a potential revenue source for insurgents to finance their rebellion. Hence, the higher the dependence of a state on natural resource exports, the higher should be the probability of civil war outbreak. However, this account was heavily criticized by other researchers. Some claimed that the conceptualization of the Primary Commodity Exports (PCE) variable does not cover relevant natural resources (Fearon 2005), others pointed at the problem of reversed causality and endogeneity (Gleditsch 1998) and also others stressed to differentiate between different natural resources according to their proneness to be looted by rebels (Ross 2003). In order to address these problems, a new variable was conceptualized. The "extraction feasibility" variable measures the degree of extractability of a particular resource. It is composed of two notions, namely...

Interviewers are a principal source of error in quantitative surveys. While surveys are often self-administered (e.g. in online surveys), it is often required to administer these face-to- face. This is the case, for example, in census surveys in low-income areas where there is little internet penetration, like that of the quality-of-life surveys presently being conducted in multiple countries through a residential door-to-door approach (Carr et al., 2018). In such situations, the social interaction between the interviewer conducting the survey and the interviewee is likely to introduce bias into the survey data collected. Interviewer effects (IE) can influence both item non-response and answer quality, i.e., participants not providing the true answer (Harling, et al., 2019). In an attempt to gain more representative data, this study conducted an exploratory analysis on the possible antecedents and consequences of interviewer effects using the Living Wage survey presently being conducted in South Africa, as the study context. To this end, I examine the systematic biasing effects associated with deploying the same group interviewers (n = 10), of the same ethnicity, age, and of equal gender distribution across five sampling areas in Cape Town in a quasi-experimental design (n = 282). This study highlighted that each interviewer is associated with a unique set of systematic bias that varies dependent on the survey item type. Sensitive items requiring respondents to disclose personal information were the most prone to bias, followed by interviewer-referencing and attitudinal items sequentially. Furthermore, this study found that gender differences in the interview had a marginal influence on the attitudes respondents are willing to share. I hope to contribute to an understanding and critical consideration of the antecedents and consequences of deploying human interviewers for collecting quantitative surveys, especially in a context where ethnic, gender and political differences are loaded in social interactions and are likely to contribute to respondents obscuring their responses.

The Geoscience Quantitative Preparation Survey (GQPS) was developed to address a deficiency in the available literature regarding the competency and preparation of early-career geologists in geoscience job-related quantitative skills – namely, geologic numeracy. The final version of the GQPS included self-confidence, usage, satisfaction, and demographic sections. The GQPS was expected to produce data that would allow for an evaluation of the geologic numeracy of early-career geologists and the success of approximately 20 years of increased focus on quantitatively literate geoscience graduates. The self-confidence section of the GQPS included quantitative methods and quantitative skills. The usage section asked whether participants used methods or skills from the confidence section in both work and non-work settings. Satisfaction items asked how satisfied participants were with the quantitative preparation they received as undergraduates, relative to career needs, and included items on quantitative problem solving, quantitative communication, and computers. Limited demographic information was collected including time since bachelor’s graduation, years of related experience, undergraduate alma mater, current job status and field, and highest level of education. Satisfaction values for quantitative problem solving and quantitative communication indicate that respondents were largely satisfied with their undergraduate preparation, with values slightly higher for the geoscience department than for the university as a whole. Satisfaction items related to the use of computers were nearly uniform across all response levels and were not indicative of satisfaction (or any other particular response). Demographic responses indicate it is reasonable to make some generalizations to the overall population of early-career geologists. Early-career geologists in the sample population showed indications of geologic numeracy. This result indicates the educational trend of the last 20 years of focus on quantitatively literate geoscience graduates has had some success, although this focus cannot be compared to prior years due to lack of data. The GQPS was successful for answering its research questions, but requires validation as a complete scale before it is likely to be used by outside parties.

OBJECTIVES: The present study aims to collect data on the pain and sensory perception of both male and female healthy individuals. Although the overarching project has been testing female controls for longer, males have been added to the protocol with the goal of expanding our understanding pain norms. This study compares pain and sensation perception between genders and looks at psychosocial factors that may cause differences between the two populations. METHODS: The protocol for this study is divided into quantitative sensory testing (QST) and questionnaires. QST is a non-invasive procedure that is used to study somatosensory functioning in individuals. This study specifically utilizes a QST battery to understand sensation and pain caused by mechanical and thermal stimuli. The deltoid and hand are used as control regions and the abdomen is the experimental area. Additionally, the Health Screening Form, Pain Rating Questionnaire, Pain Sensitivity Questionnaire, Pain Catastrophizing Scale questionnaire, and 36-item Short Form Survey Instrument are all used to gather information on participants’ medical history, mental status, and other psychosocial factors that may affect pain and sensory processing. Data collected from this protocol is then analyzed on SPSS through descriptive statistics and one-way analyses of variance. RESULTS: Throughout the protocol, there are only three values that are significantly different between the male and female control populations: the thermal sensory threshold of cold on the hand, thermal sensory threshold for heat on the hand, and pressure pain threshold on the hand. The p-values for these are 0.001, 0.013, and 0.044 respectively. Additionally, the abdomen is slightly more sensitive than the control site for certain QST measures like the pain threshold for cold temperatures. CONCLUSIONS: The lack of significant variance between genders for the majority of data points shows that both male and female healthy control perceive pain and sensation similarly. Although there may be some differences in anatomy and development, there are no distinct differences in the overall experience of these phenomena. Although these results suggest that gender does not play a significant role in pain and sensory perception, it is important to continue expanding the database in order to find more conclusive results. / 2021-06-14T00:00:00Z

This study examined quantitative EEGs of six individuals with chronic pain and compared them to an age- and gender-matched normative database of healthy control subjects in an attempt to discern whether a particular pattern of resting state EEG activity is associated with chronic pain. In the chronic pain group, significantly reduced absolute power was seen in delta and theta bandwidths at frontal sites in the eyes-closed condition. In the eyes-open condition, significantly reduced absolute power was seen in delta, theta, and alpha bandwidths at frontal, central, and temporal sites, and increased relative high beta power was seen in the parietal region. Reduced theta/high beta and delta/high beta ratios were seen in the parietal region. Quantitative EEG neuromarkers of chronic pain are suggested.

Card and Giuliano’s National Bureau of Economic Research (NBER) working paper on universal screening is discussed. This commentary provides a brief summary and critique of the article, proposes an explanation of the results in light of the author’s research on the role of nominations or screening tests in the gifted identification process, and discusses the methodological implications of this work for the field.

The late Miocene Xiaolongtan megaflora from Kaiyuan in southeast Yunnan (23°48′45″N, 103°11′52″E, 1050 m a.s.l.) was chosen for palaeoclimatic reconstruction using three quantitative techniques, i.e. the Coexistence Approach (CA), Leaf Margin Analysis (LMA), and the Climate-Leaf Analysis Multivariate Program (CLAMP). The reconstructed climatic parameters are also compared with those of the two adjacent Miocene floras currently available in Yunnan, i.e. the early to middle Miocene carpological Mangdan flora (24°24′N, 97°49′E, 1620 m a.s.l.) and the late Miocene Lühe palynoflora (25°10′N, 101°22′E, 1930 m a.s.l.). Quantitative analyses of the Xiaolongtan flora supports the previous qualitative results of a southern, humid subtropical climate, being more humid and having a slightly higher mean annual temperature (MAT) than today. The MATs calculated by CA, LMA, and CLAMP overlap (16.7-19.2 °C, 22.3 ± 2.05 °C, 18.1 ± 1.2 °C, respectively) and are close to the present day value (19.7 °C). The overlapping of temperatures derived using the three techniques is unusual and probably related to the low latitude of the Xiaolongtan area and the southern subtropical nature of its vegetation. Both the mean temperatures of the warmest month (WMT) and of the coldest month (CMT) reconstructed by CA (WMT = 25.4-26.0 °C, CMT = 7.7-8.7 °C) and CLAMP (WMT = 25.9 ± 1.6 °C, CMT = 10.8 ± 1.9 °C) are similar to those of today (WMT = 24.3 °C, CMT = 12.8 °C), but great changes appear in the mean annual precipitation (MAP). The CLAMP results suggest a higher precipitation (1964 ± 335.9 mm) than CA (1215-1639 mm), but they are much higher than the present MAP (820.5 mm). This is consistent with results from the Lühe palynoflora, which also developed under a warmer subtropical climate with higher precipitation (803.6-1254.7 mm) than that of today (815.9 mm). In contrast, the Mangdan flora, situated in a more complicated topographic region to the west of Xiaolongtan and near the Sino-Myanmar border, implies a slightly lower precipitation (1170-1300 mm) than that of today (1300-1400 mm). Overall, the wetter climate during the late Miocene around the Xiaolongtan area suggests that the Himalayas had not yet uplifted to its present altitudes at that time.

Obesity, diabetes, hypertension, and heart disease are highly heritable conditions that in aggregate are the major causes of morbidity and mortality in the developed world and are growing problems in developing countries. To map the causal genes, we conducted a population screen for these conditions on the Pacific Island of Kosrae. Family history and genetic data were used to construct a pedigree for the island. Analysis of the pedigree showed highly significant heritability for the metabolic traits under study. DNA samples from 2,188 participants were genotyped with 405 microsatellite markers with an average intermarker distance of 11 cM. A protocol using LOKI, a Markov chain Monte Carlo sampling method, was developed to analyze the Kosraen pedigree for height, a model quantitative trait. Robust quantitative trait loci for height were found on 10q21 and 1p31. This protocol was used to map a set of metabolic traits, including plasma leptin to chromosome region 5q35; systolic blood pressure to 20p12; total cholesterol to 19p13, 12q24, and 16qter; hip circumference to 10q25 and 4q23; body mass index to 18p11 and 20q13; apolipoprotein B to 2p24-25; weight to 18q21; and fasting blood sugar to 1q31-1q43. Several of these same chromosomal regions have been identified in previous studies validating the use of LOKI. These studies add information about the genetics of the metabolic syndrome and establish an analytical approach for linkage analysis of complex pedigrees. These results also lay the foundation for whole genome scans with dense sets of SNPs aimed to identifying causal genes.

Jedes Jahr werden am Universitätsklinikum Würzburg etwa 100 PatientInnen allogen stammzelltransplantiert. Für den Erfolg einer allogenen Stammzelltransplantation ist neben einer passenden Spenderauswahl und einer optimalen Vorbereitung auch die regelmäßige Nachkontrolle wichtig. Im Rahmen dieser Nachkontrollen werden unter anderem Chimärismusuntersuchungen durchgeführt. Als Chimäre wird in der Wissenschaft ein Lebewesen bezeichnet, das Zellen in sich trägt, die aus zwei oder mehr Zygoten entstanden ist. Der Begriff kommt aus der griechischen Mythologie, in der die Chimäre als Mischwesen aus Löwe, Ziege und Schlange (oder manchmal Drache) beschrieben wurde. Lange Zeit galt die STR/VNTR Methode als Goldstandard für die Nachkontrolle der Chimärismusuntersuchung. Durch Alizadeh et al. wurde bereits im Jahr 2002 eine neuartige Methode beschrieben, die mittels RT-PCR den genauen Chimärismusgrad messen kann. Diese Arbeit beschäftigte sich mit der Etablierung und Evaluierung dieser Methode der Chimärismusuntersuchung am Universitätsklinikum Würzburg. Es konnte gezeigt werden, dass sie für den klinischen Alltag geeignet ist und wurde auch im Hinblick auf äußere Störfaktoren untersucht. Darüber hinaus wurde eine Methode zur Bestimmung des CD3+ Chimärismus etabliert. Diese Untersuchung ist wichtig für die Abschätzung eines möglichen Abstoßungs- und GvHD Risikos. Seit 2013 finden auf Basis dieser Arbeit regelmäßige Chimärismusuntersuchungen am Universitätsklinikum Würzburg statt. / Every year, hematopoietic stem cell transplantations are being performed on approximately 100 patients at the university hospital Würzburg. Apart from finding a fitting stem cell donor and a perfect preparation of the recipient, follow-up examinations are essential for the long-term success of this procedure. Monitoring the chimerism after allogeneic stem cell transplantation is an essentialpart of those follow-up examinations. In science, a chimera is defined as a living organism, that contains cells deriving from different zygotes. In greek mythology, the „Chimera“ was described as a creature with the head of a lion, the body of a goat and the tail of a snake. For many years, the STR/VNTR method was the standard for post-transplant chimerism testing. In 2002, Alizadeh et al. developed a new method using RT-PCR to monitor chimerism. This dissertation evaluated and established this new method for engraftment analysis of transplanted patients at the university hospital Würzburg. It could be shown that the method was suitable for routine use in clinical practice. In addition, a method to measure CD3 + chimerism was established to evaluate the risks of GvHD or graft failure. Since 2013, chimerism is being tested at the university hospital Würzburg based on the results of this graduate thesis.