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ObjectivesThere have been many advancements in laryngeal imaging using optical coherence tomography (OCT), with varying system design and probes for use in research, office, and operating room settings. We evaluated the performance of six distinct OCT systems in imaging porcine vocal folds (cords) using computational image processing and segmentation.MethodsPorcine vocal folds were scanned using six OCT systems. Imaging system and probe performance were quantitatively assessed for signal penetration, layer differentiation, and epithelium (EP) measurement. Fitted exponential decay curves with corresponding α constant and intensity thresholding segmentation were utilized to quantify the aforementioned parameters.ResultsThe smallest average α constant and deepest signal penetration was of the SS-OCT 1700 nm 90 kHz microscope system (α = -1.74), followed by the SS-OCT 1310 nm 200 kHz VCSEL microscope system (α = -1.99), and SS-OCT 1310 nm 50 kHz rigid forward viewing endoscope system (α = -2.23). The EP was not readily visualized for three out of six systems, but was detected using automated segmentation. Average EP thickness (mean ± SD) was calculated as 55.79 ± 31.86 μm which agrees favorably with previous literature.ConclusionComparisons of OCT systems are challenging, as they encompass different probe design, optical path, and lasers, depending on application. Practical evaluation of different systems using computer based quantitative image processing and segmentation revealed basic, constructive information, such as EP measurements. To further validate the comparisons of system performance with clinical usability, in vivo human laryngeal imaging will be conducted. Further development of automated image processing and segmentation can be useful in rapid analysis of information. Lasers Surg. Med. 51:412-422, 2019. © 2019 Wiley Periodicals, Inc.

Family farming in various guises has been the dominant ownership and governance system in primary production over recorded history. This outcome has been controlled by farmers and their families, possibly due to tradition, opportunities, personal characteristics, skill sets and the nature of primary production. Of these, it is hypothesised that the farmers’ personal characteristics play a major part in the choice, and continuance, of current ownership and governance systems. Equally as important, they, and therefore the land ownership system, play a part in the efficiency of production systems and improvement of the biological and production environment. The benefits and difficulties of commonly used ownership systems in Western society are reviewed. Using a sample of New Zealand (NZ) farms, a comparison of the managers’ features for owner/operator, partnership and corporate based systems is presented. There were significant differences in many variables including the farmers’ age, education, number of children, asset levels, years on the current farm, and similar, but more importantly, the farmers in the ownership system groups had differing personal characteristics. Significantly, despite the corporate based farms employing more professional assistance, the profit levels were similar across ownership systems leaving the farmers’ characteristics the main factors correlating with system choice. However, governance systems per se are only marginally correlated with production systems and efficiency. As successive generations of farmers are unlikely to have different characteristics, and corporate based systems continue to exhibit similar profit levels, relatively simple family based systems will continue to dominate farm land ownership and control. The trends suggest family farms will increase in size and involve family conglomerates facilitating the management of larger, and in many cases multiple, farms. While currently there are few differences in biological efficiency between ownership systems, given the efficiency benefits of size and scale, this could well change with the increase of family conglomerates. Relative to increasing corporatisation, the continuance of family based ownership and governance will also be of benefit to the environment. When developing land policies, these highlighted relationships should be taken into account. This study is a first to consider personal characteristics relative to ownership. [ABSTRACT FROM AUTHOR]

Objective. To compare adjusted mortality rates of TEFRA-risk HMO enrollees and disenrollees with rates of beneficiaries enrolled in the Medicare fee-for-service sector (FFS), and to compare the time until death for decedents in these three groups. Data Source. Data are from the 124 counties with the largest TEFRA-risk HMO enrollment using 1993-1994 Medicare Denominator files for beneficiaries enrolled in the FFS and TEFRA-risk HMO sectors. Study Design. A retrospective study that tracks the mortality rates and time until death of a random sample of 1,240,120 Medicare beneficiaries in the FFS sector and 1,526,502 enrollees in HMOs between April 1, 1993 and April 1, 1994. A total of 58,201 beneficiaries switched from an HMO to the FFS sector and were analyzed separately. Principal Findings. HMO enrollees have lower relative odds of mortality than a comparable group of FFS beneficiaries. Conversely, HMO disenrollees have higher relative odds of mortality than comparable FFS beneficiaries. Among decedents in the three groups, HMO enrollees lived longer than FFS beneficiaries, who in turn lived longer than HMO disenrollees. Conclusions. Medicare TEFRA-risk HMO enrollees appear to be, on average, healthier than beneficiaries enrolled in the FFS sector, who appear to be in tum healthier than HMO disenrollees. These health status differences persist, even after controlling for beneficiary demographics and county-level variables that might confound the relationship between mortality and the insurance sector. [ABSTRACT FROM AUTHOR]