Identifying and mitigating residual vibrations in wave-based control of lumped, flexible systems

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Wave-based control (WBC) is a technique for motion control of under-actuated flexible sys-tems. It envisages actuator motion as launching a motion wave into the system, while simulta-neously absorbing any wave returning from the system. For rest-to-rest motion the net launch displacement is set at half the target displacement. In absorbing the returning wave and vibra-tions, WBC moves the system the remaining distance to the target, with zero steady-state error. The focus of this paper is on very small residual vibrations around the target position which can endure for a long time after arrival at target. This issue was discovered through a recent devel-opment within WBC context on controlling complex two-dimensional, mass-spring, beam-like arrays. To date their existence has been unidentified. This paper investigates and interprets the nature of these vibrations, explains and identifies them based on wave ideas, and finally offers a new wave-based approach to mitigate or suppress them. It also discusses their implication, not just for WBC but for the general problem of control of flexible systems

Pairing Neutral Cues with Alcohol Intoxication: New Findings in Executive and Attention Networks

Rationale: Alcohol-associated stimuli capture attention, yet drinkers differ in the precise stimuli that become paired with intoxication. Objectives: Extending our prior work to examine the influence of alcoholism risk factors, we paired abstract visual stimuli with intravenous alcohol delivered covertly and examined brain responses to these Pavlovian conditioned stimuli in fMRI when subjects were not intoxicated. Methods: Sixty healthy drinkers performed task-irrelevant alcohol conditioning that presented geometric shapes as conditioned stimuli. Shapes were paired with a rapidly rising alcohol limb (CS+) using intravenous alcohol infusion targeting a final peak breath alcohol concentration of 0.045 g/dL or saline (CS−) infusion at matched rates. On day two, subjects performed monetary delay discounting outside the scanner to assess delay tolerance and then underwent event-related fMRI while performing the same task with CS+, CS−, and an irrelevant symbol. Results: CS+ elicited stronger activation than CS− in frontoparietal executive/attention and orbitofrontal reward-associated networks. Risk factors including family history, recent drinking, sex, and age of drinking onset did not relate to the [CS+ > CS−] activation. Delay-tolerant choice and [CS+ > CS−] activation in right inferior parietal cortex were positively related. Conclusions: Networks governing executive attention and reward showed enhanced responses to stimuli experimentally paired with intoxication, with the right parietal cortex implicated in both alcohol cue pairing and intertemporal choice. While different from our previous study results in 14 men, we believe this paradigm in a large sample of male and female drinkers offers novel insights into Pavlovian processes less affected by idiosyncratic drug associations

A cooperative scheme for late leaf spot estimation in peanut using UAV multispectral images

In Australia, peanuts are mainly grown in Queensland with tropical and subtropical climates. The most common foliar disease that poses a severe threat to quality peanut production is late leaf spot (LLS). Unmanned aerial vehicles (UAVs) have been widely investigated for various plant trait estimations. The existing works on UAV-based remote sensing have achieved promising results for crop disease estimation using a mean or a threshold value to represent the plot-level image data, but these methods might be insufficient to capture the distribution of pixels within a plot. This study proposes two new methods, namely measurement index (MI) and coefficient of variation (CV), for LLS disease estimation on peanuts. We first investigated the relationship between the UAV-based multispectral vegetation indices (VIs) and the LLS disease scores at the late growth stages of peanuts. We then compared the performances of the proposed MI and CV-based methods with the threshold and mean-based methods for LLS disease estimation. The results showed that the MI-based method achieved the highest coefficient of determination and the lowest error for five of the six chosen VIs whereas the CV-based method performed the best for simple ratio (SR) index among the four methods. By considering the strengths and weaknesses of each method, we finally proposed a cooperative scheme based on the MI, the CV and the mean-based methods for automatic disease estimation, demonstrated by applying this scheme to the LLS estimation in peanuts.</p

CONTINUOUS WAVEFORM ANALYSIS OF FORCE, VELOCITY, AND POWER ADAPTATIONS TO A PERIODIZED PLYOMETRIC TRAINING PROGRAM

This study assessed kinetic and temporal profile adaptations to the countermovement jump in response to a six week periodized plyometric training program. Twenty recreationally active women participated in the study (10 training, 10 control). Testing consisted of 3 maximal countermovement jumps on a force platform prior to and after six weeks of training. Key phases of the jumps were examined to assess differences in the profiles pre- and post-training using Analysis of Characterizing Phases. Periodized plyometric training significantly altered the profiles for force, velocity, and power (p < 0.05). A combination of greater eccentric velocity and power followed by increased concentric power enhanced the stretch shortening cycle and all three variables just before takeoff likely enhancing jump height

Parallel transport in an entangled ring

This paper defines a notion of parallel transport in a lattice of quantum particles, such that the transformation associated with each link of the lattice is determined by the quantum state of the two particles joined by that link. We focus particularly on a one-dimensional lattice--a ring--of entangled rebits, which are binary quantum objects confined to a real state space. We consider states of the ring that maximize the correlation between nearest neighbors, and show that some correlation must be sacrificed in order to have non-trivial parallel transport around the ring. An analogy is made with lattice gauge theory, in which non-trivial parallel transport around closed loops is associated with a reduction in the probability of the field configuration. We discuss the possibility of extending our result to qubits and to higher dimensional lattices.Comment: 31 pages, no figures; v2 includes a new example of a qubit rin

Molecular and cellular heterogeneity in breast cancer: Challenges for personalized medicine

Breast cancer is noted for disparate clinical behaviors and patient outcomes, despite common histopathological features at diagnosis. Molecular pathogenesis studies suggest that breast cancer is a collection of diseases with variable molecular underpinnings that modulate therapeutic responses, disease-free intervals, and long-term survival. Traditional therapeutic strategies for individual patients are guided by the expression status of the estrogen and progesterone receptors (ER and PR) and human epidermal growth factor receptor 2 (HER2). Although such methods for clinical classification have utility in selection of targeted therapies, short-term patient responses and long-term survival remain difficult to predict. Molecular signatures of breast cancer based on complex gene expression patterns have utility in prediction of long-term patient outcomes, but are not yet used for guiding therapy. Examination of the correspondence between these methods for breast cancer classification reveals a lack of agreement affecting a significant percentage of cases. To realize true personalized breast cancer therapy, a more complete analysis and evaluation of the molecular characteristics of the disease in the individual patient is required, together with an understanding of the contributions of specific genetic and epigenetic alterations (and their combinations) to management of the patient. Here, we discuss the molecular and cellular heterogeneity of breast cancer, the impact of this heterogeneity on practical breast cancer classification, and the challenges for personalized breast cancer treatment

743-2 Superiority of 3D Echo vs 2D Echo for Quantitating Wall Motion Abnormality as an Index of Myocardial Infarction Size

Two-dimensional echo estimations of the fraction of myocardium showing abnormal wall motion (AWM) are often used as an index of infarct size, to establish prognosis and guide therapy. However 2D echo methods rely on image plane and geometric assumptions which may not be valid when infarction affects ventricular shape. 3D echo reconstruction of the endocardial surface can eliminate the need for these assumptions. Purpose; To use 3D echo and 2D echo to quantitate AWM in experimental acute infarction, and to correlate the extent of AWM with the pathologic determination of infarct size.MethodsCoronary ligation was performed in 14 open chest dogs, and echo imaging performed after 6 hours. 3D echo used 7–8 spatially registered short axis cross-sections to measure % of endocardial surface showing AWM. Two 2D echo methods using multiple, non-spatially registered images were evaluated. Both compared summed endocardial length showing AWM to the total of the endocardial circumferences, expressed as %. Method #1 used 7-8 short-axis slices. Method #2 used basal, mid, apical short axis + apical 4-and 2-chamber views. Percent LV mass (% mass) infarcted was determined by a standard technique.Resultsregression of [x = echo %AWM] vs [y = %mass infarcted]Echo Methodr valueStandard Error of the EstimateEquationp value3D0.94±2.6%y =0.71x-1.81%&lt;0.000120-#10.82±4.3%y =0.50x-0.66%0.001520-#2074±5,1%Y =0.47x-1.25%0.0058ConclusionThree-dimensional echocardiography is a more accurate means of non-invasively estimating myocardial infarct size in this animal model, compared to 2D echo methods