Traceability in Food Systems: An Economic Analysis of LGMA and the 2006 Spinach Outbreak

This case study presents an in-depth review of network structures and costs associated with the implementation of traceability systems in California leafy green production, distribution, and retailing. The 2006 spinach outbreak is used to assess the economic impact of trace back/forward response time of the LGMA system, an example of a tightly coupled, linear supply network. Results suggest that the benefits of traceability systems may far outweigh the costs and that costs vary significantly by technology used and by grower size. Implications are derived for cost-effectiveness of rapid response, targeted trace back/forward systems in other types of supply networks.traceability, produce, supply networks, cost-effectiveness, Food Consumption/Nutrition/Food Safety, Production Economics, Q18, I18, L51,

Multi-processor system for real-time deconvolution and flow estimation in medical ultrasound

More and more advanced algorithms are being introduced for performing signal and image processing on medical ultrasound signals. The algorithms often use the RF ultrasound signal and perform adaptive signal processing. Two examples are the cross-correlation estimator for blood velocity estimation and adaptive blind deconvolution. The first algorithm uses the RF signal from a number of pulse emissions and correlates segments within different pulse-echo lines to obtain a velocity estimate. Real-time processing makes it necessary to perform around 600 million multiplications and additions per second for this algorithm. This has until now only been possible by using the sign of the signals, and such an implementation does not give optimal performance. The second algorithm also uses the RF data, and first performs an estimation of the one-dimensional pulse in the tissue as a function of depth. Then a Kalman filter is used with a second time-reversed recursive estimation step. Here it is nec..

7. The 1970s

From View from the Dean’s Office by Robert McKersie. “I had been on the job just a week when Keith Kennedy, vice provost, called and said we needed to make a trip to Albany to meet the chancellor of SUNY, Ernest Boyer. This was late August 1971. After a few pleasantries, it became clear that this was not just the courtesy call of a new dean reporting in to the top leader of the state university. Chancellor Boyer went right to the point: a new Labor College was going to open on the premises of Local 3 IBEW’s training facility on Lexington Avenue in Manhattan, and the ILR School had to be there as a partner. It was not clear what unit of SUNY would take over the Labor College, but it was clear that given its broad mandate for labor education, the ILR School was going to play a key role.” Includes: View from the Dean’s Office; From Eric Himself; Another Perspective; Labor College Graduation: VanArsdale’s Dream Fulfilled; The View of a Visiting Faculty Member; Another Perspective; and The Student’s View

An axisymmetric time-domain spectral-element method for full-wave simulations: Application to ocean acoustics

The numerical simulation of acoustic waves in complex 3D media is a key topic in many branches of science, from exploration geophysics to non-destructive testing and medical imaging. With the drastic increase in computing capabilities this field has dramatically grown in the last twenty years. However many 3D computations, especially at high frequency and/or long range, are still far beyond current reach and force researchers to resort to approximations, for example by working in 2D (plane strain) or by using a paraxial approximation. This article presents and validates a numerical technique based on an axisymmetric formulation of a spectral finite-element method in the time domain for heterogeneous fluid-solid media. Taking advantage of axisymmetry enables the study of relevant 3D configurations at a very moderate computational cost. The axisymmetric spectral-element formulation is first introduced, and validation tests are then performed. A typical application of interest in ocean acoustics showing upslope propagation above a dipping viscoelastic ocean bottom is then presented. The method correctly models backscattered waves and explains the transmission losses discrepancies pointed out in Jensen et al. (2007). Finally, a realistic application to a double seamount problem is considered.Comment: Added a reference, and fixed a typo (cylindrical versus spherical

Tissue motion in blood velocity estimation and its simulation

Determination of blood velocities for color flow mapping systems involves both stationary echo canceling and velocity estimation. Often the stationary echo canceling filter is the limiting factor in color flow mapping and the optimization and further development of this filter is crucial to the improvement of color flow imaging. Optimization based on in-vivo data is difficult since the blood and tissue signals cannot be accurately distinguished and the correct extend of the vessel under investigation is often unknown. This study introduces a model for the simulation of blood velocity data in which tissue motion is included. Tissue motion from breathing, heart beat, and vessel pulsation were determined based on in-vivo RF-data obtained from 10 healthy volunteers. The measurements were taken at the carotid artery at one condition and in the liver at three conditions. Each measurement was repeated 10 times to cover the whole cardiac cycle and a total of 400 independent RF measurements of..

A Coupled Experimental and Computational Approach to Quantify Deleterious Hemodynamics, Vascular Alterations, and Mechanisms of Long-Term Morbidity in Response to Aortic Coarctati

Introduction Coarctation of the aorta (CoA) is associated with morbidity despite treatment. Although mechanisms remain elusive, abnormal hemodynamics and vascular biomechanics are implicated. We present a novel approach that facilitates quantification of coarctation-induced mechanical alterations and their impact on vascular structure and function, without genetic or confounding factors. Methods Rabbits underwent thoracic CoA at 10 weeks of age (~ 9 human years) to induce a 20 mm Hg blood pressure (BP) gradient using permanent or dissolvable suture thereby replicating untreated and corrected CoA. Computational fluid dynamics (CFD) was performed using imaging and BP data at 32 weeks to quantify velocity, strain and wall shear stress (WSS) for comparison to vascular structure and function as revealed by histology and myograph results. Results Systolic and mean BP was elevated in CoA compared to corrected and control rabbits leading to vascular thickening, disorganization and endothelial dysfunction proximally and distally. Corrected rabbits had less severe medial thickening, endothelial dysfunction, and stiffening limited to the proximal region despite 12 weeks of normal BP (~ 4 human years) after the suture dissolved. WSS was elevated distally for CoA rabbits, but reduced for corrected rabbits. Discussion These findings are consistent with alterations in humans. We are now poised to investigate mechanical contributions to mechanisms of morbidity in CoA using these methods

Diel and Monthly Movement Rates by Migratory and Resident Female Pronghorn

Animal movement patterns are variable, with certain species primarily being diurnal and others nocturnal. Pronghorn (Antilocapra americana) are regarded as diurnal animals moving predominately during daylight hours. Anecdotal accounts, however, suggest that pronghorn move during the night but the extent, frequency, and importance of these nocturnal movement behaviors are unknown. To evaluate movements, we combined global positioning system relocation data from collared female pronghorn in the Northern Sagebrush Steppe between 2003 and 2007 with sunrise/sunset data within a geographical information system platform. We assessed whether mean and maximum movement rates were influenced by diel period (dawn, day, dusk, and night), month (January through December), movement strategy (migrant or resident), and year individuals were captured (2003, 2005, or 2006). Diel period and month greatly influenced mean and mean maximum movement rates. Pronghorn were indeed primarily diurnal in activity but significant movement did occur at night. Our results indicate pronghorn primarily move during the daytime, a period when humans also are most active on the landscape. This movement cycle has important implications for management and conservation of pronghorn at the northern periphery of its range