Neurocontroller Alternatives for Fuzzy Ball-and-Beam Systems with Nonuniform Nonlinear Friction

The ball-and-beam problem is a benchmark for testing control algorithms. Zadeh proposed (1994) a twist to the problem, which, he suggested, would require a fuzzy logic controller. This experiment uses a beam, partially covered with a sticky substance, increasing the difficulty of predicting the ball\u27s motion. We complicated this problem even more by not using any information concerning the ball\u27s velocity. Although it is common to use the first differences of the ball\u27s consecutive positions as a measure of velocity and explicit input to the controller, we preferred to exploit recurrent neural networks, inputting only consecutive positions instead. We have used truncated backpropagation through time with the node-decoupled extended Kalman filter (NDEKF) algorithm to update the weights in the networks. Our best neurocontroller uses a form of approximate dynamic programming called an adaptive critic design. A hierarchy of such designs exists. Our system uses dual heuristic programming (DHP), an upper-level design. To our best knowledge, our results are the first use of DHP to control a physical system. It is also the first system we know of to respond to Zadeh\u27s challenge. We do not claim this neural network control algorithm is the best approach to this problem, nor do we claim it is better than a fuzzy controller. It is instead a contribution to the scientific dialogue about the boundary between the two overlapping disciplines

Multidimensional Gas Chromatography—Olfactometry for the Identification and Prioritization of Malodors from Confined Animal Feeding Operations

Odor profiling efforts were directed at applying to high-density livestock operations some of the lessons learned in resolving past, highly diverse, odor-focused investigations in the consumer product industry. Solid-phase microextraction (SPME) was used for field air sampling of odorous air near and downwind of a beef cattle feedyard and a swine finisher barn in Texas. Multidimensional gas chromatography−olfactometry (MDGC-O) was utilized in an attempt to define and prioritize the basic building blocks of odor character associated with these livestock operations. Although scores of potential odorant volatiles have been previously identified in high-density livestock operations, the odor profile results developed herein suggest that only a very few of these may constitute the preponderance of the odor complaints associated with these environments. This appeared to be especially true for the case of increasing distance from both cattle feedyard and swine barn facilities, with p-cresol consistently taking on the dominant odor impact role with ever increasing distance. In contrast, at- or near-site odor profiles were shown to be much more complex, with many of the well-known lower tier odorant compounds rising in relative significance. For the cattle feedyard at- or near-site odor profiles, trimethylamine was shown to represent a significantly greater individual odor impact relative to the more often cited livestock odorants such as hydrogen sulfide, the organic sulfides, and volatile fatty acids. This study demonstrates that SPME combined with a MDGC-O−mass spectrometry system can be used for the sampling, identification, and prioritization of odors associated with livestock

The Relationship between Knee Valgus and Clinical Measures in Professional Basketball: A CART Analysis

Background/Purpose: Lower extremity injuries occur at an amplified rate in professional basketball. Evidence suggests that knee frontal plane valgus may be associated with risk of injury. The Landing Error Scoring System includes the assessment of maximum knee valgus during a countermovement jump. The investigation of interactions among linear and non-linear factors may help the understanding of the interdependence of various measures and poor performance on the knee valgus displacement (KVD) component of the LESS in professional basketball players. The purpose of this study was to investigate predictors of knee valgus displacement on the LESS. We hypothesize that a positive finding on the knee valgus displacement component of the LESS will be predicted by select clinical measures. Methods: 47 professional basketball players participated. Measurements were completed as part of preseason mobility screening prior to the 2015-16 and 2016-17 NBA seasons. Classification and Regression Tree Analysis (CART) were used to investigate linear and non-linear interactions among predictors and their influence on KVD in players who performed the LESS test. Results: Of the 47 players included in this study, 16 players did not test positive for KVD on the LESS test and 31 did. Pruning resulted in 4 splits (r2=0.507) demonstrating that KVD was predicted by total hip rotation range of motion, dominant leg hip external rotation, and standing arch height index measure. Predictive modeling, classified 18 of the 31 players with KVD and 8 of the 16 players who tested negative for KVD. The area under the ROC curve was .9183, suggesting that classification of players using this model was not random. Conclusion: KVD and performance on the LESS has been linked with injury. CART analysis captured linear and non-linear interactions between clinical measures suggesting that lower extremity biomechanical factors may be associated with predicting KVD during performance on the LESS. Clinical Relevance: KVD and the LESS test has been shown to be predictive of injury. Identifying which clinical measures may be linked with poor performance on this test may aide clinicians in determining appropriate interventions that may be associated with improved scores and minimize risk of injury.https://ecommons.udayton.edu/dpt_symposium/1000/thumbnail.jp

Assessing Differential Drug Effect

1 online resource (PDF, 11 pages

The Utility of Functional Movement Assessment on NBA Players

Professional basketball related injuries have not declined over the last decade despite improvements in training and conditioning or medical advancements in diagnostics, surgery, or rehabilitation. A descriptive epidemiological study of 80% of the National Basketball Association (NBA) teams over 17 years reported an injury incidence of 19.1 per 1000 athlete exposures, and 59,179 games missed due to injury. Starkey found that the there has been a 12.4% increase in game-related injuries in the NBA in a 10-year period from the 1988 - 1997 seasons. It is suspected that increased contact within the NBA along with improved player athleticism, size, power, and speed have contribute to the rise in injuries. The most commonly reported injuries in the NBA as reported via the greatest number of days missed include ankle sprains, patellofemoral inflammation, knee sprains, and lumbar strains. Recent trends involve less focus on specific physical or clinical measures and increased attention on the assessment of functional movement patterns for the purpose of predicting the likelihood of injury. The Functional Movement Screen (FMSTM) was introduced as a pre-participation examination intended to evaluate the quality of seven basic movement patterns that require a balance of both mobility and stability. The functional movements tested include: deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, trunk stability push-up, and rotary stability. It is designed to assess the extremes of specific movements and positions for the purpose of identifying potential limitation, compensation, and asymmetry in individuals without obvious pathology. Recent literature has linked this screen to injury prediction in numerous populations that may be predisposed to injury, including professional football players, firefighters, collegiate female athletes, elite track and field athletes, military personnel. The majority of reliability studies conclude that the FMSTM has good intra-rater reliability. While some researchers conclude that reliability increases with additional training and clinical experience, others claim that the FMS intra-rater reliability was not improved with FMS certification. Inter- rater reliability was reported in recent studies to range from moderate and good to high. The Y-balance Test (YBT) is pre-participation assessment used to screen individuals who may have potential for lower extremity injury. This test involves the examination of dynamic balance and postural control. While research is still lacking regarding the validity and utility of the YBT-LQ, the SEBT has been reported to have a moderate to strong effect size and that this test was reliable and valid as a dynamic predictor to lower extremity injuries. No studies have investigated the outcomes of YBT as an injury predictor in professional basketball athletes or the relationship of these factors with functional movement screens.https://ecommons.udayton.edu/dpt_symposium/1011/thumbnail.jp

Testing bespoke management of foraging habitat for European turtle doves Streptopelia turtur

Agri-environment schemes (AES) are increasingly being employed to mitigate biodiversity loss in agricultural environments. The European Turtle Dove Streptopelia turtur is an obligate granivorous bird in rapid decline within both the UK (−96% since 1970) and across continental Europe (−77% since 1980), despite widespread uptake of AES. Here, we assess the efficacy of a potentially new, sown agri-environment option designed to provide abundant, accessible seed for S. turtur during the breeding season. During summer 2011 we compared vegetation structure and seed provision on trial plots to control habitat types (existing agri-environment options thought to potentially provide S. turtur foraging habitat) to assess whether trial plots performed better for foraging S. turtur than control habitats. In September 2011 all trial plots were topped (cut) and half of a subset of trial plots were then scarified (60% of soil surface disturbed). Vegetation structure on topped, and topped and scarified trial plots was measured during summer 2012 to determine which management regime was most effective in maintaining suitable sward structure and seed provision into the second year. No control habitat type produced as much seed important in S. turtur diet as trial plots at any point during year one. Trial plots provided accessible vegetation structure early in the season with no difference in vegetation metrics between trial plots and previously published data on S. turtur foraging locations. However, to allow later access, management is required during mid-June to open up the sward through localized topping or scarification. Vegetation structure during year two was generally too dense to attract foraging S. turtur. However, scarifying trial plots during the September following sowing encouraged self-seeding of Fumaria officinalis (a plant species historically forming a significant proportion of S. turtur diet during the breeding season) into the second year, with this species present in 16% of scarified trial plots compared to only 4% of topped trial plots during year two. Thus, autumn scarification, possibly followed by topping or scarification of part of the trial plots in June, is necessary for trial plots to provide more seed and access for S. turtur than existing agri-environment options during year two. We recommend modifications to our original seed mix in order to reduce vegetation density and improve vegetation structure. The study provides an example of the need to strike the right balance between food abundance and accessibility, through vegetation structure, when designing agri-environment scheme management options that provide food for birds

Longitudinal cohort study of depression, post-traumatic stress, and alcohol use in South African women who attend alcohol serving venues

CITATION; Abler, L.A. et al. 2014. Longitudinal cohort study of depression, post-traumatic stress, and alcohol use in South African women who attend alcohol serving venues. BMC Psychiatry, 14(1):224, doi:10.1186/s12888-014-0224-9.The original publication is available at http://www.biomedcentral.com/1471-244X/14/224Background: In South Africa, alcohol use poses a public health burden. Hazardous alcohol use often co-occurs with psychological distress (e.g., depression and post-traumatic stress). However, the majority of the research establishing the relationship between alcohol use and psychological distress has been cross-sectional, so the nature of co-occurring changes in psychological distress and alcohol use over time is not well characterized. The objective of this study is to examine the longitudinal relationship between psychological distress and alcohol use among South African women who attend alcohol serving venues. Methods Four waves of data were collected over the course of a year from 560 women in a Cape Town township who attended drinking venues. At each assessment wave, participants reported depressive symptoms, post-traumatic stress symptoms, and alcohol use. Multilevel growth models were used to: 1) assess the patterns of alcohol use; 2) examine how depressive symptoms uniquely, post-traumatic stress symptoms uniquely, and depressive and post-traumatic stress symptoms together were associated with alcohol use; and 3) characterize the within person and between person associations of depressive symptoms and post-traumatic stress symptoms with alcohol use. Results Women reported high levels of alcohol use throughout the study period, which declined slightly over time. Post-traumatic stress symptoms were highly correlated with depressive symptoms. Modeled separately, both within person and between person depressive and post-traumatic stress symptoms were uniquely associated with alcohol use. When modeled together, significant between person effects indicated that women who typically have more post-traumatic stress symptoms, when controlling for depressive symptoms, are at risk for increased alcohol use; however, women with more depressive symptoms, controlling for post-traumatic stress symptoms, do not have differential risk for alcohol use. Significant within person effects indicated an interaction between depressive and post-traumatic stress symptoms; women reported more alcohol use than usual at times when they had higher post-traumatic stress symptoms, and this increase in alcohol use was further exacerbated for women who also had higher depressive symptoms than usual. Conclusions These findings suggest that interventions targeting post-traumatic stress, especially when post-traumatic stress is comorbid with depression, may reduce alcohol use among South African women who drink.Publishers' Versio

Population-level variation in senescence suggests an important role for temperature in an endangered mollusc

Age-related declines in survival and function (senescence) were thought not to exist in wild populations as organisms, and particularly in invertebrates, do not live long enough. While, recent evidence has demonstrated that senescence is both common and measurable even in wild populations under field conditions, there are still organisms that are thought to exhibit “negligible senescence”. We explore variation in rates and patterns of senescence in the biogerontological model organism Margaritifera margaritifera across five populations, which differ in their age profile. In particular, we tested the theory of negligible senescence using time-at-death records for 1091 specimens of M. margaritifera. There is clear evidence of senescence in all populations, as indicated by an increase in mortality with age, but the nature of the relationship varies subtly between populations. We find strong evidence of a mortality plateau at later ages in some populations but this is unequivocally absent from others. We then demonstrate that the temporal scaling of the rates of senescence between five populations of M. margaritifera can be explained by the variation in the thermal environment of the population. Hence climate change may pose a threat to the demography of this long-lived, endangered species, and a greater understanding of the relationship between river temperature and population structure will be essential to secure the species against global temperature increases. Our findings demonstrate that useful insights can be drawn from a non-invasive monitoring method to derive demographic data, and we suggest a wide-scale application of this method to monitor populations across the whole latitudinal (and, hence, thermal) range of the species