Purpose: Lung function is typically characterized by spirometer measurements, which do not offer spatially specific information. Imaging during exhalation provides spatial information but is challenging due to large movement over a short time. The purpose of this work is to provide a solution to lung imaging during forced expiration using accelerated magnetic resonance imaging. The method uses radial golden angle stack-of-stars gradient echo acquisition and compressed sensing reconstruction. Methods: A technique for dynamic three-dimensional imaging of the lungs from highly undersampled data is developed and tested on six subjects. This method takes advantage of image sparsity, both spatially and temporally, including the use of reference frames called bookends. Sparsity, with respect to total variation, and residual from the bookends, enables reconstruction from an extremely limited amount of data. Results: Dynamic three-dimensional images can be captured at sub-150 ms temporal resolution, using only three (or less) acquired radial lines per slice per timepoint. The images have a spatial resolution of 4.6 x 4.6 x 10 mm. Lung volume calculations based on image segmentation are compared to those from simultaneously acquired spirometer measurements. Conclusion: Dynamic lung imaging during forced expiration is made possible by compressed sensing accelerated dynamic three-dimensional radial magnetic resonance imaging. (C) 2015 Wiley Periodicals, Inc.

In Ni, Pearson and Poteshmans' (2005) Journal of Financial Economics-article, they claim that the expiration-day price-distribution of optionable stocks is subject to inefficiencies caused by stock price manipulation and portfolio rebalancing by delta hedgers. In this thesis, two main shortcomings of Ni et al.'s (2005) study are identified. In particular, they appear to have been ignorant of fundamental microstructure factors, and they did not derive an expression to represent the theoretical price-distribution of the relevant assets. After accounting for essential microstructure variables, and calculating the theoretical distribution, results that contradict Ni et al. (2005) are found. In particular, optionable stocks are found to experience efficiency gains on expiration days, and the distribution of underlying asset prices is closer to its theoretical benchmark on expiration days relative to non-expiration days.

2 pp. / With the exception of infant formula and baby food, product dating is not required by federal regulations. There is no uniform system used for food dating by manufacturers in the U.S. Although dating of some foods is required by more than 20 states, some states do not require any date codes. This publication is a brief guide for how to read food dating, which includes; types of dates, safety after dates expire, changing dates, dating of infant formula and baby food, can codes, dates on egg cartons, and storage times.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

The Conservation Reserve Program (CRP) has become increasingly important in Texas due to the high level of program participation, particularly in the high plains of Texas. There is also a seemingly large amount of CRP contracts that will expire, particularly in the next five years. As these contracts expire, it becomes very important for landowners to evaluate fully the options that are available for future land use. This research focused primarily on the ten counties in Texas having the most acres of CRP enrollment, which include Gaines, Deaf Smith, Lamb, Hale, Floyd, Dallam, Hockley, Terry, Castro, and Swisher Counties. The primary objective was to provide landowners in these counties with a comprehensive list of options available after CRP contract expiration. The options were identified as re-enrollment in CRP, conversion back into crop production, lease land to a tenant as rangeland, or lease land to a tenant as cropland. Latin Hypercube simulation was used to generate a stochastic value for probable net returns per acre for the four options. The four options were then evaluated based on a variety of methods typically used to rank risky alternatives. The results indicate that CRP enrollment is the most preferred option for landowners. Dryland crop production, while it can return very high net returns per acre, also has the highest amount of risk involved. However, it is important to note that the best ranking method and decision are dependent on the specific decision maker and situation. The second objective of the research was to determine if there are measurable economic impacts to the agricultural services industry associated with CRP enrollment. OLS regression models were only run for five of the ten counties in the study area due to a lack of data reported by the Bureau of Economic Analysis. Of the five counties modeled, the Gaines, Dallam, and Hale County models indicated that CRP has played a significant role in the annual earnings of the agricultural services industry. The results suggest that there would be a benefit in conducting further research to examine the relationship between CRP enrollment and the agricultural services sector.

Bakgrund: Marklyft är en funktionell helkroppsövning som används vid rehabilitering såvälsom vid träning för styrkeökning. Övningen ställer höga krav på aktivering av bålmuskulatur. Vid utförande av marklyft används ofta andningstekniken Valsalva manövern med syfte att stabilisera bålen för att tillåta till maximal kraftproduktion. Vid en utförd Valsalva manöverhar det intra abdominala trycket visats öka jämfört med andra andningstekniker. Maximalexpiration är en andningsteknik som vanligtvis inte används vid marklyft men som visats geen ökad aktivering av bålmuskulaturen. Syfte: Syftet med studien var att undersökamuskelaktivering av bålmuskulatur vid marklyft mellan tre olika andningstekniker. Metod: Fyra personer rekryterades till studien. Deltagare utförde marklyft i samband med en Valsalva manöver samt en maximal expiration vid belastningar på 50 och 70% av 1RM. I sambandmed marklyften mättes EMG aktiviteten av transversus abdominis/obliquus internus,obliquus externus, lumbala multifider och erector spinae. Resultat: Samtliga deltagareuppvisade en högre EMG aktivitet mätt i % av den maximala volontära kontraktionen avstuderad muskulatur när marklyftet utfördes i samband med en maximal expiration.Konklusion: Resultatet av studien tyder på att andningstekniken som används vid ettmarklyft har en effekt på rekryteringen av stabiliserande bålmuskulatur. Vid en maximal expiration sågs en högre aktivering av musklerna transversus abdominis/obliquus internus, obliquus externus, lumbala multifider och erector spinae. Ytterligare forskning krävs för attdra en slutsats angående exakt vilken effekt andningstekniker har på muskelrekrytering ochprestation vid marklyft.

Since 2000, the Chinese securities market has introduced private placement refinancing programs from foreign markets. Private placement has gradually emerged as an important refinancing method for domestic listed companies in China. However, any emerging financing means has some drawbacks. In the case of the newly introduced private placements, its manifestation in the Chinese market is the significant fluctuations of stock prices before and after the expiration dates of the lockup periods for stocks issued through private placement and announcements of private placement plans (disclosure plans, receiving approval from the China Securities Regulatory Commission, etc.) and even significant declines, resulting in most investors suffering unexpected losses. Scholars abroad have conducted several systematic and extensive studies on private placement. However, owing to the short history of private placement practice in China and its unique features, research on this subject is limited. With its gradual maturity, the private placement practice has gradually emerged as important means of financing consideration for listed companies in China. Therefore, in-depth research on the effects of private placements becomes essential.From 2013 to 2016, the domestic private placement market was wisely popular. By the end of 2016, the number of private placement projects, the amount of investment, and number of unlocked stocks had reached the peak. The release of large amounts of money significantly impacted the market. Investors observed the impact of the unlocked stocks on excess returns. Moreover, the company’s announcement before and after the lock-in period expiration has a psychological effect on investors, thus affecting their investment behaviors. Therefore, this empirical study focuses on the two types of impacts: excess returns and announcement effects. This study selected the data of unlocking through private placement of A shares in 2013–2016 as the sample and adopted statistical methods to analyze changes in excess return over the Shanghai and Shenzhen 300 Index of 10 days before and after the lock-in period expiration date of private placements. It is found that the negative impact of unlocking on the stock price is mainly reflected before unlocking, especially in the 5 trading days before unlocking. The negative impact is not significant after unlocking. Then, by grouping comparison, it is shown that for stocks with different market capitalizations, company ownership structures, and percentages of unlocked stocks over total shares outstanding, there are significant differences in the cumulative excess returns before and after the lock-in period expiration dates. For further verification, this study applies multiple regressions on the influencing factors of the cumulative excess return of stocks before, during, and after unlocking, indicating that the level of market capitalization of the stock, company ownership structure, and the percentage of unlocked stock indeed exert a negative impact. Therefore, it is confirmed that investors can formulate the best trading strategy before and after unlocking, based on factors such as market capitalization, company ownership structure, and percentages of unlocked stock. Finally, a case study of Huangshan Tourism is carried out to further support the conclusion of the empirical analysis. / Business Administration/Finance

Critical care patients are often connected to ventilators, to support or replace their breathing. The ventilators deliver a mixture of gas to the patient by applying a specific volume or pressure, and then the patient exhales passively. This thesis is based of the hypothesis that a slower reduction of the expiration pressure could benefit intensive care patients connected to a ventilator. To enable research within the area, a device which can control the expiration is needed. In this thesis project, an expiration valve was controlled to create different pressure patterns during expiration. To facilitate the research and the usage of the expiration control, an application software was created with the purpose to simulate relevant pressure, flow and volume curves. The prototype is an expiration cassette created for the ventilator Servo-i by Maquet Getinge Group. To enable flexibility, the prototype is external and no information is transmitted from or to the ventilator. The prototype has its own flow and pressure sensors. The different pressure patterns which the prototype uses are designed as a linear decrease and as if a constant resistance was added to the system. The user can also create their own pressure pattern, by deciding 20 pressure points in the duration of two seconds. The simulation application was designed with the ability to simulate the same pressure patterns available with the prototype. By using a lung model, it is possible to simulate the ideal pressure, flow and volume in the lungs which can be expected from the chosen expiration control. During the implementation, two different types of lung models were evaluated in order to determine the specificity required. The prototype was tested with settings which were chosen to challenge the performance of the control. Some problematic areas were detected, such as high pressures or large volumes. However, the prototype was judged to perform well enough to be used in animal trials. The lung model used for the simulation application was a simple model of the lung, consisting of a resistor and a capacitor in series. The simulations were compared with the real system with the purpose to get an indication on the difference between theory and reality. The application presents the expected behavior when using the expiration control. However, it should be kept in mind by the user that the application represents a theoretical model.

Auscultation has been widely regarded as one of the most important noninvasive diagnostic tools for clinical diagnosis of the respiratory tract. The purpose of this thesis was to develop a software application capable of extracting the key features of respiratory sound signals from the lungs and trachea of healthy persons. The efficacy of the program was evaluated by the verification of the important features of the sound signals from the left and right lungs and the trachea such as 1) right and left lung symmetry and 2) dissimilarity between the trachea and both lungs. The program was developed in LabView and was designed to capture the respiratory sound signals from the lungs and the trachea in real-time and process them in the time and frequency domains for further analysis. The features compared were 1) signal amplitude in the time domain and 2) power spectra in the frequency domain. Results of the study had shown that the program had been able to verify that 1) the key features of the breath sound signals from the left and right lungs were similar and 2) the features of the signals from the trachea and both lungs were different.

O padrão respiratório é formado por 3 fases: inspiração, pós-inspiração, e expiração ativa. Os mecanismos neurais de controle respiratório são organizados por um sistema de neurônios localizados no bulbo. Evidências sugerem o envolvimento dos neurônios quimiossensíveis do núcleo retrotrapezóide (RTN) no controle da expiração ativa. Portanto, o objetivo desta dissertação foi esclarecer a existência de uma projeção do RTN para o a região que contém os neurônios pré-motores do grupamento respiratório ventrolateral caudal (cVRG), o fenótipo dos neurônios e os neurotransmissores envolvidos nessa projeção. Utilizaram-se ratos Wistar adultos, submetidos a procedimentos imunoistoquímicos e eletrofisiológicos. Os resultados mostraram evidências anatomofuncionais de projeções excitatórias da região do RTN para o cVRG. Esta projeção está ativa durante uma situação de hipercapnia, mas não envolve neurônios serotoninérgicos da rafe e tem pouco envolvimento dos neurônios quimiossensíveis do RTN. / The eupnoeic pattern of respiration consists of three phases: inspiration, post-inspiration and stage 2 of expiration (E2). The neural mechanisms for respiratory control are carefully organized by neuron system localized into the medulla oblongata and this system is highly sensitive to CO2. Evidences suggest the involvement of chemosensitive neurons of the retrotrapezoid nucleus (RTN) in the control of expiratory activity of the caudal ventral respiratory group (cVRG) (Janczewski e Feldman, 2006a). In this study, investigate the existence of a projection the RTN from cVRG, the phenotype of the neurons and the neurotransmitters involved in this projection. The experiments were performed in adult male Wistar rats, submitted to immunohistochemical and electrophysiological approaches. The results showed anatomofunctional evidences of excitatory projections from RTN to caudal ventral respiratory group region. This pathway is active during hypercapnia, has minimal involvement of Phox2b neurons of RTN and do not involve serotonergic neurons of raphe.