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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Impact of minimum hiring requirements (AB 1725) on the recruitment and employment of community college vocational and technical teachers in California

Davis, Victor Corey 01 January 1995 (has links)
No description available.
172

Statistická analýza výroby / Statistical analysis of production

Kovaříková, Ludmila January 2009 (has links)
The aim of Master's thesis is to apply statistical methods in production process. The assignment of the thesis is to describe and evaluate pressing process which is the part of posistor production. The first theoretical part contains introduction to the mathematical statistics, verifying assumptions about the data, describing the regression analysis, the analysis of variance and the part of the design of experiment. The second practical part is focused on design, performing and interpreting of experiments. The thesis is developed according to requirements of company EPCOS s.r.o. Šumperk. Statistical program MINITAB Rlease 14, which is supported by company, was used for all computations.
173

The Effects of Adulthood Nicotine Treatment on D2-Mediated Behavior and Neurotrophins of Rats Neonatally Treated with Quinpirole

Brown, Russell W., Perna, Marla K., Schaefer, Tori L., Williams, Michael T. 01 April 2006 (has links)
This study was designed to analyze the effects of nicotine on yawning behavior and neurotrophin content in the hippocampus and frontal cortex of D2-receptor primed female adult Sprague-Dawley rats. Animals were neonatally treated with quinpirole, a dopamine (DA) D2/D3 agonist, from postnatal day 1-21 (P1-21) and raised to P60 and administered nicotine tartarate (0.3 mg/kg free base) or saline twice daily for 14 days. One day after nicotine treatment had ceased, the number of yawns was recorded for 1 h in response to an acute injection of quinpirole (i.p., 100 microg/kg). Yawning is a D2-receptor mediated event. D2-primed rats demonstrated a significant increase in yawning in response to acute quinpirole compared with that of controls, but nicotine did not alleviate this effect. Neonatal quinpirole treatment produced a significant decrease of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in the hippocampus that was alleviated by adulthood nicotine treatment. Interestingly, nicotine treatment to controls produced a significant increase of NGF in the frontal cortex, but a significant decrease of both NGF and BDNF in the hippocampus and BDNF in the frontal cortex. The decreases shown in NGF and BDNF is contrary to past findings that have shown nicotine to produce significant increases of hippocampal NGF and BDNF, but these past studies utilized male rats or mice or were performed in vitro. This study shows that nicotine has complex interactions with NGF and BDNF in D2-primed and control animals, and emphasizes the importance of gender differences when analyzing nicotine's effects on neurotrophins.
174

Nicotine Sensitization in Adult Male and Female Rats Quinpirole-Primed as Neonates

Perna, Marla K., Cope, Zackary A., Maple, Amanda M., Longacre, Ian D., Correll, Jennifer A., Brown, Russell W. 01 July 2008 (has links)
RATIONALE: Increases in dopamine D2-like receptor function are common in several psychological disorders that demonstrate a four to five fold increase in nicotine abuse compared to the general population.OBJECTIVE: The objective of this study was to analyze the interaction of sex differences and sensitization to nicotine in rats D2 receptor primed as neonates.MATERIALS AND METHODS: A total of 32 male and 32 female Sprague-Dawley rats derived from eight litters were ontogenetically treated with quinpirole (1 mg/kg) or saline from postnatal days (P) 1-21 and raised to adulthood. At P60, all animals were given an acute injection of quinpirole HCl (100 microg/kg) and yawns were counted for 1 h. Yawning has been shown to be a behavioral event mediated by D2-like receptors. Beginning on P61-65, animals were habituated to a locomotor arena and subsequently administered either nicotine (0.5 mg/kg free base) or saline (intraperitoneal) every second day for 3 weeks. Approximately 15 min after each injection, animals were placed into the arena and horizontal activity and vertical rears were recorded.RESULTS: A robust increase of yawning was observed at P60 in D2 primed as compared to saline controls. Priming of D2-like receptors increased the locomotor response to nicotine in horizontal activity in both males and females, but females demonstrated a more robust hypoactive locomotor response to initial nicotine treatment when compared to saline-treated females. Nicotine also produced a significant decrease of vertical rearing in both males and females.CONCLUSIONS: It appears that D2 receptor priming enhances sensitization to nicotine in adult rats, and females may be more behaviorally sensitive to nicotine than males.
175

Quantifying Contributions to the Variance of Permeability and Porosity within the Western Belt Sandstones of the Cypress Formation, Illinois Basin

Dulaney, Nathaniel Frederick 08 June 2020 (has links)
No description available.
176

Investigating Differences in Volunteer Administrator Challenges and Management Practices

Thorne, David 28 May 2021 (has links)
No description available.
177

Long-Term Effects of Strokes on Bone Mass

Hamdy, Ronald C., Moore, S W., Cancellaro, V A., Harvill, L. M. 01 September 1995 (has links)
The purpose of the study was to determine the long-term effects of muscle weakness secondary to strokes on the bone mineral content of the hemiparetic limb. Patients who had experienced single recent strokes were studied. The bone mineral content of each limb was measured by Dual Energy X-ray Absorptiometry using the region of interest analysis program. Muscle strength of each muscle group was ranked using the Oxford scale, and the mean was calculated for each limb. Bone and muscle parameters were measured within seven days after the stroke and repeated thereafter at monthly intervals for up to 6 mo. A repeated measures analysis of variance, Newman-Keuls pair-wise comparisons, and orthogonal contrasts were done for each parameter. Significance levels were set at P < 0.05. Sixteen patients were included in this study. Demineralization was more pronounced in the upper than lower limbs. Demineralization of bones on the paralyzed side started during the first month after the stroke and gradually progressed. By the fourth month, the bone mineral content decreased by a mean of 9.3% (P = 0.01) and 3.7% (P = 0.01) in the upper and lower limbs, respectively, for the 11 patients followed for 4 mo. In the patients we followed for more than 4 mo, there was no further significant mineral loss. No change in bone mineral content was observed in the healthy nonparetic limbs. In conclusion, after a stroke, bone demineralization occurs in the paralyzed side and reaches its maximum within 3 to 4 mo. Arms are affected more than legs.
178

Statistical quality assurance of IGUM : Statistical quality assurance and validation of IGUM in a steady and dynamic gas flow prior to proof of concept

Kornsäter, Elin, Kallenberg, Dagmar January 2022 (has links)
To further support and optimise the production of diving tables for the Armed Forces of Sweden, a research team has developed a new machine called IGUM (Inert Gas UndersökningsMaskin) which aims to measure how inert gas is taken up and exhaled. Due to the new design of machine, the goal of this thesis was to statistically validate its accuracy and verify its reliability.  In the first stage, a quality assurance of the linear position conversion key of IGUM in a steady and known gas flow was conducted. This was done by collecting and analysing data in 29 experiments followed by examination with ordinary least squares, hypothesis testing, analysis of variance, bootstrapping and Bayesian hierarchical modelling. Autocorrelation among the residuals were detected but concluded to not have an impact on the results due to the bootstrap analysis. The results showed an estimated conversion key equal to 1.276 ml/linear position which was statistically significant for all 29 experiments.  In the second stage, it was examined if and how well IGUM could detect small additions of gas in a dynamic flow. The breathing machine ANSTI was used to simulate the sinus pattern of a breathing human in 24 experiments where 3 additions of 30 ml of gas manually was added into the system. The results were analysed through sinusoidal regression where three dummy variables represented the three additions of gas in each experiment. To examine if IGUM detects 30 ml for each input, the previously statistically proven conversion key at 1.276ml/linear position was used. An attempt was made to remove the seasonal trend in the data, something that was not completely successful which could influence the estimations. The results showed that IGUM indeed can detect these small gas additions, where the amount detected showed some differences between dummies and experiments. This is most likely since not enough trend has been removed, rather than IGUM not working properly.
179

Astrostatistics: Statistical Analysis of Solar Activity from 1939 to 2008

Yousef, Mohammed A. 10 April 2014 (has links)
No description available.
180

[pt] ESTUDO DO IMPACTO DO PROCESSO DE AMOSTRAGEM NA INCERTEZA DE MEDIÇÃO DE ALGUNS PARÂMETROS FÍSICOQUÍMICOS EM ÁGUA E ÓLEO DIESEL / [en] STUDY OF THE IMPACT OF THE SAMPLING PROCESS ON THE MEASUREMENT UNCERTAINTY OF SOME PHYSICAL-CHEMICAL PARAMETERS IN WATER AND DIESEL OIL

VIVIANE DE JESUS LEITE 26 June 2020 (has links)
[pt] O processo de medição é constituído por um conjunto de sub processos no qual seu início está na seleção da amostra até o final da marcha analítica. Para melhor compreensão, estabeleceu-se que a incerteza proveniente do processo de medição é constituída pela associação da incerteza proveniente do conjunto desses sub processos. A literatura organizou esse conjunto em duas grandes vertentes, o processo de amostragem e o processo analítico, cada um com suas incertezas características. Visando melhor estimar a incerteza de medição, é necessário considerar integralmente a incerteza proveniente de ambos os processos, sem antecipadamente determinar qual componente será mais significativo para a incerteza de medição. Este trabalho teve como motivação o desconhecimento da contribuição da incerteza da amostragem na incerteza de medição. Uma vez que o processo de amostragem é normalmente realizado por profissionais pouco experientes, sem ter conhecimento do quanto a incerteza da amostragem pode impactar na incerteza de medição. O objetivo desta dissertação foi avaliar o quão significativa é a incerteza da amostragem na incerteza de medição, além de estimular a disseminação da cultura desta prática em medições físico-químicas. As metodologias utilizadas para o desenvolvimento deste trabalho foram a análise do estado da arte da incerteza da amostragem e o tratamento de um conjunto de dados por quatro diferentes técnicas estatísticas: análise de variância clássica, análise de variância robusta, e dois modelos diferentes da Range Statistics. Os resultados mostraram que não há um padrão de comportamento no que tange à incerteza da amostragem versus a incerteza analítica, bem como a ausência de metodologias que leve em consideração as características dos dados. Conclui-se que a incerteza da amostragem pode impactar a incerteza de medição, independente da matriz e/ou grandeza em questão. / [en] The measurement process consists of a set of sub-processes where the beginning is in the selection of the sample until the end of the analytical steps. In a simplified way, it can be established that the uncertainty coming from the measurement process is constituted by the association of the uncertainty coming from the set of these sub-processes. The literature has organized this set of subprocesses into two important areas, the sampling process and the analytical process, each one with its own uncertainties characteristics. In order to better estimate the measurement uncertainty, it is necessary to fully consider the uncertainty arising from both processes without firstly determining which component will be most significant for the measurement uncertainty. This work project was motivated by the indifference to the sampling process, which is usually carried out by little experienced professionals, without knowledge of how much uncertainty of sampling can affect the measurement uncertainty. The objective of this dissertation was to evaluate how much uncertainty is the uncertainty of the measurement uncertainty in addition to stimulating the dissemination of the culture of this practice in physicochemical measurements; since, actually, only analytical uncertainty is privileged. The methodologies used were the analysis of the state of art of sampling uncertainty and the treatment of a data set by four different statistical techniques: classical variance analysis, robust variance analysis, and two different models of the Range Statistics. The results showed that there is no behavior pattern regarding to sampling uncertainty versus analytical uncertainty, as well as the absence of methodologies that take into consideration the characteristics of the data. It is concluded that the sampling uncertainty can impact the uncertainty of measurement, regardless of the matrix and / or quantity in question.

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