Nonlinear filtering in object and Fourier space in a joint transform optical correlator: comparison and experimental realization

The use of different kinds of nonlinear filtering in a joint transform correlator are studied and compared. The study is divided into two parts, one corresponding to object space and the second to the Fourier domain of the joint power spectrum. In the first part, phase and inverse filters are computed; their inverse Fourier transforms are also computed, thereby becoming the reference in the object space. In the Fourier space, the binarization of the power spectrum is realized and compared with a new procedure for removing the spatial envelope. All cases are simulated and experimentally implemented by a compact joint transform correlator.

Reduction of the effect of aberrations in a joint transform correlator

We report the study of the influence of optical aberrations in a joint-transform correlator: The wave aberration of the optical system is computed from data obtained by ray tracing. Three situations are explored: We consider the aberration only in the first diffraction stage (generation of power spectrum), then only in the second (transformation of the power spectrum into correlation), and finally in both stages simultaneously. The results show that the quality of the correlation is determined mostly by the aberrations of the first diffraction stage and that we can optimize the setup by moving the cameras along the optical axis to a suitable position. The good agreement between the predicted data and the experimental results shows that the method explains well the behavior of optical diffraction systems when aberrations are taken into account.

Audit report on the Iowa Water Pollution Control Works Financing Program and the Iowa Drinking Water Facilities Financing Program, joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources for the year ended June 30, 2011

Audit report on the Iowa Water Pollution Control Works Financing Program and the Iowa Drinking Water Facilities Financing Program, joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources for the year ended June 30, 2011

Ankle joint pressure in pes cavovarus after lateralizing calcaneal osteotomies

BACKGROUND: Tendon transfers and calcaneal osteotomies are commonly used to treat symptoms related to medial ankle arthrosis in fixed pes cavovarus. However, the relative effect of these osteotomies in terms of lateralizing the ground contact point of the hindfoot and redistributing ankle joint contact stresses are unknown. MATERIALS AND METHODS: Pes cavovarus with fixed hindfoot varus was simulated in eight cadaver specimens. The effect of three types of calcaneal osteotomies on the migration of the center of force and tibiotalar peak pressure at 300 N axial static load (half-body weight) were recorded using pressure sensors. RESULTS: A significant lateral shift of the center of force was observed: 4.9 mm for the laterally closing Z-shaped osteotomy with additional lateralization of the tuberosity, 3.4 mm for the lateral sliding osteotomy of the calcaneal tuberosity, and 2.7 mm for the laterally closing Z-shaped osteotomy (all p < 0.001). A significant peak pressure reduction was recorded: -0.53 MPa for the Z-shaped osteotomy with lateralization, -0.58 MPa for the lateral sliding osteotomy of the calcaneal tuberosity, and -0.41 MPa for the Z-shaped osteotomy (all p < 0.01). CONCLUSION: This cadaver study supports the hypothesis that lateralizing calcaneal osteotomies substantially help to normalize ankle contact stresses in pes cavovarus.

Multiplex PCR of sonication fluid accurately differentiates between prosthetic joint infection and aseptic failure.

OBJECTIVE: Cultures have limited sensitivity in the diagnosis of prosthetic joint infection (PJI), especially in low-grade infections. We assessed the value of multiplex PCR in differentiating PJI from aseptic failure (AF). METHODS: Included were patients in whom the joint prosthesis was removed and submitted for sonication. The resulting sonication fluid was cultured and investigated by multiplex PCR, and compared with periprosthetic tissue culture. RESULTS: Among 86 explanted prostheses (56 knee, 25 hip, 3 elbow and 2 shoulder prostheses), AF was diagnosed in 62 cases (72%) and PJI in 24 cases (28%). PJI was more common detected by multiplex PCR (n=23, 96%) than by periprosthetic tissue (n=17, 71%, p=0.031) or sonication fluid culture (n=16, 67%, p=0.016). Among 12 patients with PJI who previously received antibiotics, periprosthetic tissue cultures were positive in 8 cases (67%), sonication fluid cultures in 6 cases (50%) and multiplex PCR in 11 cases (92%). In AF cases, periprosthetic tissue grew organisms in 11% and sonication fluid in 10%, whereas multiplex PCR detected no organisms. CONCLUSIONS: Multiplex PCR of sonication fluid demonstrated high sensitivity (96%) and specificity (100%) for diagnosing PJI, providing good discriminative power towards AF, especially in patients previously receiving antibiotics.

Official Positions for FRAX® clinical regarding smoking from Joint Official Positions Development Conference of the International Society for Clinical Densitometry and International Osteoporosis Foundation on FRAX®.

The worldwide prevalence of smoking has been estimated at about 50% in men, and 10% in women, with larger variations among different populations studied. Smoking has been shown to affect many organ systems resulting in severe morbidity and increased mortality. In addition, smoking has been identified as a predictor of ten-year fracture risk in men and women, largely independent of an individual's bone mineral density. This finding has eventually lead to incorporation of this risk factor into FRAX®, an algorithm that has been developed to calculate an individual's ten-year fracture risk. However, only little, or conflicting data is available on a possible association between smoking dose, duration, length of time after cessation, type of tobacco and fracture risk, limiting this risk factor's applicability in the context of FRAX®.

Corynebacterium bovis shoulder prosthetic joint infection: the first reported case.

We report the first case of Corynebacterium bovis shoulder prosthetic joint infection. The organism was isolated from intraoperative tissue culture and from the removed prosthesis using sonication. A 2-stage exchange and 3 months of antibiotic therapy were performed. C. bovis may cause implant-associated infections, which can manifest as low-grade infection.

Joint Enrollment Report, 2011

The Iowa Department of Education collects information on joint enrollment in Iowa’s 15 community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. Most jointly enrolled students enroll through Senior Year Plus programs such as PSEO (Postsecondary Enrollment Options) and concurrent enrollment. Others enroll independently by paying tuition or enrolling in courses delivered through contractual agreements that do not meet the definition of concurrent enrollment. For more information about Senior Year Plus programs, please refer to the department’s website. This report consists of fiscal year and trend data on joint enrollment including headcount enrollment, credit hours, student demographics, and enrollment by program type and offering arrangement. All data included in this report is taken from the Community College Management Information System (MIS) and confirmed by each college, unless otherwise noted.

Analysis of joint laxity after total ankle arthroplasty: cadaver study.

BACKGROUND: Clinical results of total ankle arthroplasty with early designs were disappointing. Recently-developed ankle prostheses have good mid-term results; however, limited information is available regarding effects of total ankle arthroplasty on ankle laxity. METHODS: Eight cadaveric lower extremities were tested with a custom device which enabled measurement of multi-axial forces, moments, and displacement during applied axial, shear, and rotational loading. Tests consisted of anterior-posterior and medial-lateral translation and internal-external rotation of the talus relative to the tibia during axial loads on the tibia simulating body weight (700 N) and an unloaded condition (5 N). Tests were performed in neutral, dorsiflexion, and plantarflexion. Laxity was determined for the intact ankle, and following insertion of an unconstrained total ankle implant, comparing load-displacement curve. FINDINGS: Laxity after total ankle arthroplasty did not approximate the normal ankle in most conditions tested. Displacement was significantly greater for total ankle arthroplasty in both posterior and lateral translation, and internal rotation, with 5 N axial loading, and anterior-posterior, medial-lateral translation, and internal-external rotation for 700 N axial loading. For the 700 N axial load condition, in the neutral ankle position, total anterior-posterior translation averaged 0.4 mm (SD 0.2 mm), but 6.0 mm (SD 1.5 mm) after total ankle arthroplasty (P<0.01). This study demonstrated more laxity in the replaced ankle than normal ankle for both unloaded and 700 N axially loaded conditions. INTERPRETATION: These data indicate the increased responsibility of the ligaments for ankle laxity after total ankle arthroplasty and suggest the importance of meticulous ligament reconstruction with total ankle arthroplasty operations.

Joint Official Positions of the International Society for Clinical Densitometry and International Osteoporosis Foundation on FRAX(®). Executive Summary of the 2010 Position Development Conference on Interpretation and use of FRAX® in clinical practice.

The International Society for Clinical Densitometry (ISCD) and the International Osteoporosis Foundation (IOF) convened the FRAX(®) Position Development Conference (PDC) in Bucharest, Romania, on November 14, 2010, following a two-day joint meeting of the ISCD and IOF on the "Interpretation and Use of FRAX(®) in Clinical Practice." These three days of critical discussion and debate, led by a panel of international experts from the ISCD, IOF and dedicated task forces, have clarified a number of important issues pertaining to the interpretation and implementation of FRAX(®) in clinical practice. The Official Positions resulting from the PDC are intended to enhance the quality and clinical utility of fracture risk assessment worldwide. Since the field of skeletal assessment is still evolving rapidly, some clinically important issues addressed at the PDCs are not associated with robust medical evidence. Accordingly, some Official Positions are based largely on expert opinion. Despite limitations inherent in such a process, the ISCD and IOF believe it is important to provide clinicians and technologists with the best distillation of current knowledge in the discipline of bone densitometry and provide an important focus for the scientific community to consider. This report describes the methodology and results of the ISCD-IOF PDC dedicated to FRAX(®).

Audit report on the Iowa Water Pollution Control Works Financing Program and the Iowa Drinking Water Facilities Financing Program, joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources for the year ended June 30, 2012

Audit report on the Iowa Water Pollution Control Works Financing Program and the Iowa Drinking Water Facilities Financing Program, joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources for the year ended June 30, 2012

Joint Enrollment 2012

This report summarizes joint enrollment in Iowa's community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. This report contains fiscal year data for the state's 15 community colleges reported through the Community College Management Information System (MIS) and confirmed by each college.

Quality Control/Quality Assurance Testing for Joint Density and Segregation of Asphalt Mixtures, TR-623, 2013

Longitudinal joint quality control/assurance is essential to the successful performance of asphalt pavements and it has received considerable amount of attention in recent years. The purpose of the study is to evaluate the level of compaction at the longitudinal joint and determine the effect of segregation on the longitudinal joint performance. Five paving projects with the use of traditional butt joint, infrared joint heater, edge restraint by milling and modified butt joint with the hot pinch longitudinal joint construction techniques were selected in this study. For each project, field density and permeability tests were made and cores from the pavement were obtained for in-lab permeability, air void and indirect tensile strength. Asphalt content and gradations were also obtained to determine the joint segregation. In general, this study finds that the minimum required joint density should be around 90.0% of the theoretical maximum density based on the AASHTO T166 method. The restrained-edge by milling and butt joint with the infrared heat treatment construction methods both create the joint density higher than this 90.0% limit. Traditional butt joint exhibits lower density and higher permeability than the criterion. In addition, all of the projects appear to have segregation at the longitudinal joint except for the edge-restraint by milling method.