Demant, Kirsa M; Vinberg, Maj; Kessing, Lars V; Miskowiak, Kamilla W
2015-09-30
Cognitive dysfunction is prevalent in bipolar disorder (BD). However, the evidence regarding the association between subjective cognitive complaints, objective cognitive performance and psychosocial function is sparse and inconsistent. Seventy seven patients with bipolar disorder who presented cognitive complaints underwent assessment of objective and subjective cognitive function and psychosocial functioning as part of their participation in two clinical trials. We investigated the association between global and domain-specific objective and subjective cognitive function and between global cognitive function and psychosocial function. We also identified clinical variables that predicted objective and subjective cognitive function and psychosocial functioning. There was a correlation between global subjective and objective measures of cognitive dysfunction but not within the individual cognitive domains. However, the correlation was weak, suggesting that cognitive complaints are not an assay of cognition per se. Self-rated psychosocial difficulties were associated with subjective (but not objective) cognitive impairment and both subjective cognitive and psychosocial difficulties were predicted by depressive symptoms. Our findings indicate that adequate assessment of cognition in the clinical treatment of BD and in drug trials targeting cognition requires implementation of not only subjective measures but also of objective neuropsychological tests. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Multiscale moment-based technique for object matching and recognition
NASA Astrophysics Data System (ADS)
Thio, HweeLi; Chen, Liya; Teoh, Eam-Khwang
2000-03-01
A new method is proposed to extract features from an object for matching and recognition. The features proposed are a combination of local and global characteristics -- local characteristics from the 1-D signature function that is defined to each pixel on the object boundary, global characteristics from the moments that are generated from the signature function. The boundary of the object is first extracted, then the signature function is generated by computing the angle between two lines from every point on the boundary as a function of position along the boundary. This signature function is position, scale and rotation invariant (PSRI). The shape of the signature function is then described quantitatively by using moments. The moments of the signature function are the global characters of a local feature set. Using moments as the eventual features instead of the signature function reduces the time and complexity of an object matching application. Multiscale moments are implemented to produce several sets of moments that will generate more accurate matching. Basically multiscale technique is a coarse to fine procedure and makes the proposed method more robust to noise. This method is proposed to match and recognize objects under simple transformation, such as translation, scale changes, rotation and skewing. A simple logo indexing system is implemented to illustrate the performance of the proposed method.
LDRD Final Report: Global Optimization for Engineering Science Problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
HART,WILLIAM E.
1999-12-01
For a wide variety of scientific and engineering problems the desired solution corresponds to an optimal set of objective function parameters, where the objective function measures a solution's quality. The main goal of the LDRD ''Global Optimization for Engineering Science Problems'' was the development of new robust and efficient optimization algorithms that can be used to find globally optimal solutions to complex optimization problems. This SAND report summarizes the technical accomplishments of this LDRD, discusses lessons learned and describes open research issues.
Comparison of global optimization approaches for robust calibration of hydrologic model parameters
NASA Astrophysics Data System (ADS)
Jung, I. W.
2015-12-01
Robustness of the calibrated parameters of hydrologic models is necessary to provide a reliable prediction of future performance of watershed behavior under varying climate conditions. This study investigated calibration performances according to the length of calibration period, objective functions, hydrologic model structures and optimization methods. To do this, the combination of three global optimization methods (i.e. SCE-UA, Micro-GA, and DREAM) and four hydrologic models (i.e. SAC-SMA, GR4J, HBV, and PRMS) was tested with different calibration periods and objective functions. Our results showed that three global optimization methods provided close calibration performances under different calibration periods, objective functions, and hydrologic models. However, using the agreement of index, normalized root mean square error, Nash-Sutcliffe efficiency as the objective function showed better performance than using correlation coefficient and percent bias. Calibration performances according to different calibration periods from one year to seven years were hard to generalize because four hydrologic models have different levels of complexity and different years have different information content of hydrological observation. Acknowledgements This research was supported by a grant (14AWMP-B082564-01) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.
JEFFERSON, ANGELA L.; BARAKAT, LAMIA P.; GIOVANNETTI, TANIA; PAUL, ROBERT H.; GLOSSER, GUILA
2009-01-01
This study examined the contribution of object perception and spatial localization to functional dependence among Alzheimer's disease (AD) patients. Forty patients with probable AD completed measures assessing verbal recognition memory, working memory, object perception, spatial localization, semantic knowledge, and global cognition. Primary caregivers completed a measure of activities of daily living (ADLs) that included instrumental and basic self-care subscales (i.e., IADLs and BADLs, respectively). Stepwise multiple regressions revealed that global cognition accounted for significant portions of variance among the ADL total, IADL, and BADL scores. However, when global cognition was removed from the model, object perception was the only significant cognitive predictor of the ADL total and IADL subscale scores, accounting for 18.5% and 19.3% of the variance, respectively. When considering multiple cognitive components simultaneously, object perception and the integrity of the inferotemporal cortex is important in the completion of functional abilities in general and IADLs in particular among AD patients. PMID:16822730
Are Medical Students Assigning Proper Global Assessment of Functioning Scores?
ERIC Educational Resources Information Center
Warsi, Mustafa K.; Sattar, S. Pirzada; Din, Amad U.; Petty, Frederick; Padala, Prasad R.
2007-01-01
Objective: This article seeks to determine whether medical students can estimate the appropriate score for the Global Assessment of Functioning (GAF) compared with psychiatry residents and staff psychiatrists. The authors hypothesized that medical students' estimations of GAF scores for patients in clinical vignettes would differ from those…
Leek, E Charles; Roberts, Mark; Oliver, Zoe J; Cristino, Filipe; Pegna, Alan J
2016-08-01
Here we investigated the time course underlying differential processing of local and global shape information during the perception of complex three-dimensional (3D) objects. Observers made shape matching judgments about pairs of sequentially presented multi-part novel objects. Event-related potentials (ERPs) were used to measure perceptual sensitivity to 3D shape differences in terms of local part structure and global shape configuration - based on predictions derived from hierarchical structural description models of object recognition. There were three types of different object trials in which stimulus pairs (1) shared local parts but differed in global shape configuration; (2) contained different local parts but shared global configuration or (3) shared neither local parts nor global configuration. Analyses of the ERP data showed differential amplitude modulation as a function of shape similarity as early as the N1 component between 146-215ms post-stimulus onset. These negative amplitude deflections were more similar between objects sharing global shape configuration than local part structure. Differentiation among all stimulus types was reflected in N2 amplitude modulations between 276-330ms. sLORETA inverse solutions showed stronger involvement of left occipitotemporal areas during the N1 for object discrimination weighted towards local part structure. The results suggest that the perception of 3D object shape involves parallel processing of information at local and global scales. This processing is characterised by relatively slow derivation of 'fine-grained' local shape structure, and fast derivation of 'coarse-grained' global shape configuration. We propose that the rapid early derivation of global shape attributes underlies the observed patterns of N1 amplitude modulations. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
NASA Astrophysics Data System (ADS)
Sergeyev, Yaroslav D.; Kvasov, Dmitri E.; Mukhametzhanov, Marat S.
2018-06-01
The necessity to find the global optimum of multiextremal functions arises in many applied problems where finding local solutions is insufficient. One of the desirable properties of global optimization methods is strong homogeneity meaning that a method produces the same sequences of points where the objective function is evaluated independently both of multiplication of the function by a scaling constant and of adding a shifting constant. In this paper, several aspects of global optimization using strongly homogeneous methods are considered. First, it is shown that even if a method possesses this property theoretically, numerically very small and large scaling constants can lead to ill-conditioning of the scaled problem. Second, a new class of global optimization problems where the objective function can have not only finite but also infinite or infinitesimal Lipschitz constants is introduced. Third, the strong homogeneity of several Lipschitz global optimization algorithms is studied in the framework of the Infinity Computing paradigm allowing one to work numerically with a variety of infinities and infinitesimals. Fourth, it is proved that a class of efficient univariate methods enjoys this property for finite, infinite and infinitesimal scaling and shifting constants. Finally, it is shown that in certain cases the usage of numerical infinities and infinitesimals can avoid ill-conditioning produced by scaling. Numerical experiments illustrating theoretical results are described.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mueller, Juliane
MISO is an optimization framework for solving computationally expensive mixed-integer, black-box, global optimization problems. MISO uses surrogate models to approximate the computationally expensive objective function. Hence, derivative information, which is generally unavailable for black-box simulation objective functions, is not needed. MISO allows the user to choose the initial experimental design strategy, the type of surrogate model, and the sampling strategy.
On global optimization using an estimate of Lipschitz constant and simplicial partition
NASA Astrophysics Data System (ADS)
Gimbutas, Albertas; Žilinskas, Antanas
2016-10-01
A new algorithm is proposed for finding the global minimum of a multi-variate black-box Lipschitz function with an unknown Lipschitz constant. The feasible region is initially partitioned into simplices; in the subsequent iteration, the most suitable simplices are selected and bisected via the middle point of the longest edge. The suitability of a simplex for bisection is evaluated by minimizing of a surrogate function which mimics the lower bound for the considered objective function over that simplex. The surrogate function is defined using an estimate of the Lipschitz constant and the objective function values at the vertices of a simplex. The novelty of the algorithm is the sophisticated method of estimating the Lipschitz constant, and the appropriate method to minimize the surrogate function. The proposed algorithm was tested using 600 random test problems of different complexity, showing competitive results with two popular advanced algorithms which are based on similar assumptions.
Depp, Colin A; Harmell, Alexandrea L; Vahia, Ipsit V; Mausbach, Brent T
2015-01-01
Objectives Our objective was to examine the association of mobile phone use and ownership with psychopathology, cognitive functioning and functional outcome in 196 outpatients aged 40 and older who were diagnosed with schizophrenia. Methods Participants reported their past and current mobile phone use on a standardized self-report scale and they were administered tests of global cognition, functional capacity and informant-rated functional outcome. Results The great majority of subjects had used a mobile phone (78%) but few currently owned one (27%). After adjusting for age (mean age 51), any past mobile phone use was associated with less severe negative symptoms, and higher global cognitive performance, functional capacity, and functional outcome. A total of 60% of participants reported being comfortable with mobile phones, but comfort was not associated with any cognitive or functional outcomes. Conclusions Most older patients with schizophrenia have used mobile phones and lifetime mobile phone use is a positive indicator of cognitive and functional status. PMID:25768842
Guaranteed convergence of the Hough transform
NASA Astrophysics Data System (ADS)
Soffer, Menashe; Kiryati, Nahum
1995-01-01
The straight-line Hough Transform using normal parameterization with a continuous voting kernel is considered. It transforms the colinearity detection problem to a problem of finding the global maximum of a two dimensional function above a domain in the parameter space. The principle is similar to robust regression using fixed scale M-estimation. Unlike standard M-estimation procedures the Hough Transform does not rely on a good initial estimate of the line parameters: The global optimization problem is approached by exhaustive search on a grid that is usually as fine as computationally feasible. The global maximum of a general function above a bounded domain cannot be found by a finite number of function evaluations. Only if sufficient a-priori knowledge about the smoothness of the objective function is available, convergence to the global maximum can be guaranteed. The extraction of a-priori information and its efficient use are the main challenges in real global optimization problems. The global optimization problem in the Hough Transform is essentially how fine should the parameter space quantization be in order not to miss the true maximum. More than thirty years after Hough patented the basic algorithm, the problem is still essentially open. In this paper an attempt is made to identify a-priori information on the smoothness of the objective (Hough) function and to introduce sufficient conditions for the convergence of the Hough Transform to the global maximum. An image model with several application dependent parameters is defined. Edge point location errors as well as background noise are accounted for. Minimal parameter space quantization intervals that guarantee convergence are obtained. Focusing policies for multi-resolution Hough algorithms are developed. Theoretical support for bottom- up processing is provided. Due to the randomness of errors and noise, convergence guarantees are probabilistic.
NASA Astrophysics Data System (ADS)
Shoemaker, C. A.; Pang, M.; Akhtar, T.; Bindel, D.
2016-12-01
New parallel surrogate global optimization algorithms are developed and applied to objective functions that are expensive simulations (possibly with multiple local minima). The algorithms can be applied to most geophysical simulations, including those with nonlinear partial differential equations. The optimization does not require simulations be parallelized. Asynchronous (and synchronous) parallel execution is available in the optimization toolbox "pySOT". The parallel algorithms are modified from serial to eliminate fine grained parallelism. The optimization is computed with open source software pySOT, a Surrogate Global Optimization Toolbox that allows user to pick the type of surrogate (or ensembles), the search procedure on surrogate, and the type of parallelism (synchronous or asynchronous). pySOT also allows the user to develop new algorithms by modifying parts of the code. In the applications here, the objective function takes up to 30 minutes for one simulation, and serial optimization can take over 200 hours. Results from Yellowstone (NSF) and NCSS (Singapore) supercomputers are given for groundwater contaminant hydrology simulations with applications to model parameter estimation and decontamination management. All results are compared with alternatives. The first results are for optimization of pumping at many wells to reduce cost for decontamination of groundwater at a superfund site. The optimization runs with up to 128 processors. Superlinear speed up is obtained for up to 16 processors, and efficiency with 64 processors is over 80%. Each evaluation of the objective function requires the solution of nonlinear partial differential equations to describe the impact of spatially distributed pumping and model parameters on model predictions for the spatial and temporal distribution of groundwater contaminants. The second application uses an asynchronous parallel global optimization for groundwater quality model calibration. The time for a single objective function evaluation varies unpredictably, so efficiency is improved with asynchronous parallel calculations to improve load balancing. The third application (done at NCSS) incorporates new global surrogate multi-objective parallel search algorithms into pySOT and applies it to a large watershed calibration problem.
Ghosh, Sayan; Das, Swagatam; Vasilakos, Athanasios V; Suresh, Kaushik
2012-02-01
Differential evolution (DE) is arguably one of the most powerful stochastic real-parameter optimization algorithms of current interest. Since its inception in the mid 1990s, DE has been finding many successful applications in real-world optimization problems from diverse domains of science and engineering. This paper takes a first significant step toward the convergence analysis of a canonical DE (DE/rand/1/bin) algorithm. It first deduces a time-recursive relationship for the probability density function (PDF) of the trial solutions, taking into consideration the DE-type mutation, crossover, and selection mechanisms. Then, by applying the concepts of Lyapunov stability theorems, it shows that as time approaches infinity, the PDF of the trial solutions concentrates narrowly around the global optimum of the objective function, assuming the shape of a Dirac delta distribution. Asymptotic convergence behavior of the population PDF is established by constructing a Lyapunov functional based on the PDF and showing that it monotonically decreases with time. The analysis is applicable to a class of continuous and real-valued objective functions that possesses a unique global optimum (but may have multiple local optima). Theoretical results have been substantiated with relevant computer simulations.
NASA Astrophysics Data System (ADS)
Green, R. O.; Asner, G. P.; Thompson, D. R.; Mouroulis, P.; Eastwood, M. L.; Chien, S.
2017-12-01
Global coverage imaging spectroscopy in the solar reflected energy portion of the spectrum has been identified by the Earth Decadal Survey as an important measurement that enables a diverse set of new and time critical science objectives/targets for the Earth system. These science objectives include biodiversity; ecosystem function; ecosystem biogeochemistry; initialization and constraint of global ecosystem models; fire fuel, combustion, burn severity, and recovery; surface mineralogy, geochemistry, geologic processes, soils, and hazards; global mineral dust source composition; cryospheric albedo, energy balance, and melting; coastal and inland water habitats; coral reefs; point source gas emission; cloud thermodynamic phase; urban system properties; and more. Traceability of these science objectives to spectroscopic measurement in the visible to short wavelength infrared portion of the spectrum is summarized. New approaches, including satellite constellations, to acquire these global imaging spectroscopy measurements is presented drawing from recent advances in optical design, detector technology, instrument architecture, thermal control, on-board processing, data storage, and downlink.
Allan, Eric; Manning, Pete; Alt, Fabian; Binkenstein, Julia; Blaser, Stefan; Blüthgen, Nico; Böhm, Stefan; Grassein, Fabrice; Hölzel, Norbert; Klaus, Valentin H; Kleinebecker, Till; Morris, E Kathryn; Oelmann, Yvonne; Prati, Daniel; Renner, Swen C; Rillig, Matthias C; Schaefer, Martin; Schloter, Michael; Schmitt, Barbara; Schöning, Ingo; Schrumpf, Marion; Solly, Emily; Sorkau, Elisabeth; Steckel, Juliane; Steffen-Dewenter, Ingolf; Stempfhuber, Barbara; Tschapka, Marco; Weiner, Christiane N; Weisser, Wolfgang W; Werner, Michael; Westphal, Catrin; Wilcke, Wolfgang; Fischer, Markus
2015-08-01
Global change, especially land-use intensification, affects human well-being by impacting the delivery of multiple ecosystem services (multifunctionality). However, whether biodiversity loss is a major component of global change effects on multifunctionality in real-world ecosystems, as in experimental ones, remains unclear. Therefore, we assessed biodiversity, functional composition and 14 ecosystem services on 150 agricultural grasslands differing in land-use intensity. We also introduce five multifunctionality measures in which ecosystem services were weighted according to realistic land-use objectives. We found that indirect land-use effects, i.e. those mediated by biodiversity loss and by changes to functional composition, were as strong as direct effects on average. Their strength varied with land-use objectives and regional context. Biodiversity loss explained indirect effects in a region of intermediate productivity and was most damaging when land-use objectives favoured supporting and cultural services. In contrast, functional composition shifts, towards fast-growing plant species, strongly increased provisioning services in more inherently unproductive grasslands. © 2015 The Authors Ecology Letters published by John Wiley & Sons Ltd and CNRS.
DQM: Decentralized Quadratically Approximated Alternating Direction Method of Multipliers
NASA Astrophysics Data System (ADS)
Mokhtari, Aryan; Shi, Wei; Ling, Qing; Ribeiro, Alejandro
2016-10-01
This paper considers decentralized consensus optimization problems where nodes of a network have access to different summands of a global objective function. Nodes cooperate to minimize the global objective by exchanging information with neighbors only. A decentralized version of the alternating directions method of multipliers (DADMM) is a common method for solving this category of problems. DADMM exhibits linear convergence rate to the optimal objective but its implementation requires solving a convex optimization problem at each iteration. This can be computationally costly and may result in large overall convergence times. The decentralized quadratically approximated ADMM algorithm (DQM), which minimizes a quadratic approximation of the objective function that DADMM minimizes at each iteration, is proposed here. The consequent reduction in computational time is shown to have minimal effect on convergence properties. Convergence still proceeds at a linear rate with a guaranteed constant that is asymptotically equivalent to the DADMM linear convergence rate constant. Numerical results demonstrate advantages of DQM relative to DADMM and other alternatives in a logistic regression problem.
Objectively-measured outdoor time and physical and psychological function among older adults.
Harada, Kazuhiro; Lee, Sangyoon; Lee, Sungchul; Bae, Seongryu; Harada, Kenji; Suzuki, Takao; Shimada, Hiroyuki
2017-10-01
Objective measurements of outdoor time are essential to establishing evidence about the health benefits of going outdoors among older adults. To better understanding the health benefits of going outdoors, clarification of potential mediators to connect going outdoors with health benefits is necessary. The present study aimed to investigate associations of objectively-measured outdoor time with older adults' physical and psychological function, and examine the mediating role of physical activity on these associations. Baseline data from a randomized control trial of physical activity among older adults with global cognitive impairment was used. Data from 192 participants were analyzed. Measures included steps-per-day, objectively-measured outdoor time per day using global positioning systems, physical function (cardiorespiratory fitness, lower-extremity strength), psychological function (depression, well-being) and basic factors. Path analysis showed that outdoor time was significantly associated with steps-per-day (path coefficient = 0.23) and depression (path coefficient = -0.16). Outdoor time was not directly associated with cardiorespiratory fitness, lower-extremity strength and well-being. However, steps-per-day was associated with cardiorespiratory fitness (path coefficient = 0.18), lower-extremity strength (path coefficient = -0.22) and well-being (path coefficient = 0.14). We found that objectively-measured outdoor time was indirectly associated with physical function, and both directly and indirectly with psychological function through physical activity among older adults. This finding indicates that going outdoors influences older adults' health outcomes, and is mainly mediated by physical activity. Geriatr Gerontol Int 2017; 17: 1455-1462. © 2016 Japan Geriatrics Society.
Multi-objective aerodynamic shape optimization of small livestock trailers
NASA Astrophysics Data System (ADS)
Gilkeson, C. A.; Toropov, V. V.; Thompson, H. M.; Wilson, M. C. T.; Foxley, N. A.; Gaskell, P. H.
2013-11-01
This article presents a formal optimization study of the design of small livestock trailers, within which the majority of animals are transported to market in the UK. The benefits of employing a headboard fairing to reduce aerodynamic drag without compromising the ventilation of the animals' microclimate are investigated using a multi-stage process involving computational fluid dynamics (CFD), optimal Latin hypercube (OLH) design of experiments (DoE) and moving least squares (MLS) metamodels. Fairings are parameterized in terms of three design variables and CFD solutions are obtained at 50 permutations of design variables. Both global and local search methods are employed to locate the global minimum from metamodels of the objective functions and a Pareto front is generated. The importance of carefully selecting an objective function is demonstrated and optimal fairing designs, offering drag reductions in excess of 5% without compromising animal ventilation, are presented.
Van Rheenen, Tamsyn E; Rossell, Susan L
2014-06-01
People with bipolar disorder (BD) experience significant psychosocial impairment. Understandings of the nature and causes of such impairment is limited by the lack of research exploring the extent to which subjectively reported functioning should be valued as an indicator of objective dysfunction, or examining the relative influence of neurocognition, social cognition and emotion regulation on these important, but different aspects of psychosocial functioning in the context of mania and depression symptoms. This study aimed to address this paucity of research by conducting a comprehensive investigation of psychosocial functioning in a well characterised group of BD patients. Fifty-one BD patients were compared to 52 healthy controls on objectively and subjectively assessed psychosocial outcomes. Relationships between current mood symptoms, psychosocial function and neurocognitive, social cognitive and emotion regulation measures were also examined in the patient group. Patients had significantly worse scores on the global objective and subjective functioning measures relative to controls. In the patient group, although these scores were correlated, regression analyses showed that variance in each of the measures was explained by different predictors. Depressive symptomatology was the most important predictor of global subjective functioning, and neurocognition had a concurrent and important influence with depressive symptoms on objective psychosocial function. Emotion regulation also had an indirect effect on psychosocial functioning via its influence on depressive symptomatology. As this study was cross-sectional in nature, we are unable to draw precise conclusions regarding contributing pathways involved in psychosocial functioning in BD. These results suggest that patients' own evaluations of their subjective functioning represent important indicators of the extent to which their observable function is impaired. They also highlight the importance of incorporating cognitive and emotion regulation assessments into clinical practice when working to reduce psychosocial dysfunction with patients diagnosed with BD. Copyright © 2014 Elsevier B.V. All rights reserved.
Cowley, Benjamin; Lukander, Kristian
2016-01-01
Background: Recognition of objects and their context relies heavily on the integrated functioning of global and local visual processing. In a realistic setting such as work, this processing becomes a sustained activity, implying a consequent interaction with executive functions. Motivation: There have been many studies of either global-local attention or executive functions; however it is relatively novel to combine these processes to study a more ecological form of attention. We aim to explore the phenomenon of global-local processing during a task requiring sustained attention and working memory. Methods: We develop and test a novel protocol for global-local dissociation, with task structure including phases of divided (“rule search”) and selective (“rule found”) attention, based on the Wisconsin Card Sorting Task (WCST). We test it in a laboratory study with 25 participants, and report on behavior measures (physiological data was also gathered, but not reported here). We develop novel stimuli with more naturalistic levels of information and noise, based primarily on face photographs, with consequently more ecological validity. Results: We report behavioral results indicating that sustained difficulty when participants test their hypotheses impacts matching-task performance, and diminishes the global precedence effect. Results also show a dissociation between subjectively experienced difficulty and objective dimension of performance, and establish the internal validity of the protocol. Contribution: We contribute an advance in the state of the art for testing global-local attention processes in concert with complex cognition. With three results we establish a connection between global-local dissociation and aspects of complex cognition. Our protocol also improves ecological validity and opens options for testing additional interactions in future work. PMID:26941689
Visual Attention at Three Months as a Predictor of Cognitive Functioning at Two Years of Age.
ERIC Educational Resources Information Center
Lewis, Michael; Brooks-Gunn, Jeanne
1981-01-01
The predictive power of various cognitive skills at three months of age in terms of later cognitive functioning was examined. Visual habituation and recovery predicted later intellectual functioning at 24 months better than global intelligence or object permanence scores. Changes in cognitive functioning may be a transformation of skills.…
Assessment of Executive Functions in Prader-Willi Syndrome and Relationship with Intellectual Level
ERIC Educational Resources Information Center
Chevalere, J.; Postal, V.; Jauregui, J.; Copet, P.; Laurier, V.; Thuilleaux, D.
2013-01-01
Introduction: The aim of the present study was to determine whether individuals with Prader--Willi syndrome (PWS) have impaired global executive functioning and whether this deficit is linked with intellectual disability. Another objective focussed on the variability in performance of intellectual quotient (IQ) and executive functions (EF)…
Zhong, Shangping; Chen, Tianshun; He, Fengying; Niu, Yuzhen
2014-09-01
For a practical pattern classification task solved by kernel methods, the computing time is mainly spent on kernel learning (or training). However, the current kernel learning approaches are based on local optimization techniques, and hard to have good time performances, especially for large datasets. Thus the existing algorithms cannot be easily extended to large-scale tasks. In this paper, we present a fast Gaussian kernel learning method by solving a specially structured global optimization (SSGO) problem. We optimize the Gaussian kernel function by using the formulated kernel target alignment criterion, which is a difference of increasing (d.i.) functions. Through using a power-transformation based convexification method, the objective criterion can be represented as a difference of convex (d.c.) functions with a fixed power-transformation parameter. And the objective programming problem can then be converted to a SSGO problem: globally minimizing a concave function over a convex set. The SSGO problem is classical and has good solvability. Thus, to find the global optimal solution efficiently, we can adopt the improved Hoffman's outer approximation method, which need not repeat the searching procedure with different starting points to locate the best local minimum. Also, the proposed method can be proven to converge to the global solution for any classification task. We evaluate the proposed method on twenty benchmark datasets, and compare it with four other Gaussian kernel learning methods. Experimental results show that the proposed method stably achieves both good time-efficiency performance and good classification performance. Copyright © 2014 Elsevier Ltd. All rights reserved.
Multiobjective optimization techniques for structural design
NASA Technical Reports Server (NTRS)
Rao, S. S.
1984-01-01
The multiobjective programming techniques are important in the design of complex structural systems whose quality depends generally on a number of different and often conflicting objective functions which cannot be combined into a single design objective. The applicability of multiobjective optimization techniques is studied with reference to simple design problems. Specifically, the parameter optimization of a cantilever beam with a tip mass and a three-degree-of-freedom vabration isolation system and the trajectory optimization of a cantilever beam are considered. The solutions of these multicriteria design problems are attempted by using global criterion, utility function, game theory, goal programming, goal attainment, bounded objective function, and lexicographic methods. It has been observed that the game theory approach required the maximum computational effort, but it yielded better optimum solutions with proper balance of the various objective functions in all the cases.
ERIC Educational Resources Information Center
Greene, Michelle R.; Oliva, Aude
2009-01-01
Human observers are able to rapidly and accurately categorize natural scenes, but the representation mediating this feat is still unknown. Here we propose a framework of rapid scene categorization that does not segment a scene into objects and instead uses a vocabulary of global, ecological properties that describe spatial and functional aspects…
Adding ecosystem function to agent-based land use models
USDA-ARS?s Scientific Manuscript database
The objective of this paper is to examine issues in the inclusion of simulations of ecosystem functions in agent-based models of land use decision-making. The reasons for incorporating these simulations include local interests in land fertility and global interests in carbon sequestration. Biogeoche...
Potential and limitations of inferring ecosystem photosynthetic capacity from leaf functional traits
Talie Musavi; Mirco Migliavacca; Martine Janet van de Weg; Jens Kattge; Georg Wohlfahrt; Peter M. van Bodegom; Markus Reichstein; Michael Bahn; Arnaud Carrara; Tomas F. Domingues; Michael Gavazzi; Damiano Gianelle; Cristina Gimeno; André Granier; Carsten Gruening; Kateřina Havránková; Mathias Herbst; Charmaine Hrynkiw; Aram Kalhori; Thomas Kaminski; Katja Klumpp; Pasi Kolari; Bernard Longdoz; Stefano Minerbi; Leonardo Montagnani; Eddy Moors; Walter C. Oechel; Peter B. Reich; Shani Rohatyn; Alessandra Rossi; Eyal Rotenberg; Andrej Varlagin; Matthew Wilkinson; Christian Wirth; Miguel D. Mahecha
2016-01-01
The aim of this study was to systematically analyze the potential and limitations of using plant functional trait observations from global databases versus in situ data to improve our understanding of vegetation impacts on ecosystem functional properties (EFPs). Using ecosystem photosynthetic capacity as an example, we first provide an objective approach to derive...
ERIC Educational Resources Information Center
Bird, Hector R.; Canino, Glorisa J.; Davies, Mark; Ramirez, Rafael; Chavez, Ligia; Duarte, Cristiane; Shen, Sa
2005-01-01
Objective: This article provides the results of the psychometric testing of the Brief Impairment Scale (BIS). The BIS is a 23-item instrument that evaluates three domains of functioning: interpersonal relations, school/work functioning, and self-care/self-fulfilment. It capitalizes on the strengths of existing global measures while addressing some…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lewis, M.; Grimshaw, A.
1996-12-31
The Legion project at the University of Virginia is an architecture for designing and building system services that provide the illusion of a single virtual machine to users, a virtual machine that provides secure shared object and shared name spaces, application adjustable fault-tolerance, improved response time, and greater throughput. Legion targets wide area assemblies of workstations, supercomputers, and parallel supercomputers, Legion tackles problems not solved by existing workstation based parallel processing tools; the system will enable fault-tolerance, wide area parallel processing, inter-operability, heterogeneity, a single global name space, protection, security, efficient scheduling, and comprehensive resource management. This paper describes themore » core Legion object model, which specifies the composition and functionality of Legion`s core objects-those objects that cooperate to create, locate, manage, and remove objects in the Legion system. The object model facilitates a flexible extensible implementation, provides a single global name space, grants site autonomy to participating organizations, and scales to millions of sites and trillions of objects.« less
Perceptual grouping in the human brain: common processing of different cues.
Seymour, Kiley; Karnath, Hans-Otto; Himmelbach, Marc
2008-12-03
The perception of global scenes and objects consisting of multiple constituents is based on the integration of local elements or features. Gestalt grouping cues, such as proximity or similarity, can aid this process. Using functional MRI we investigated whether grouping guided by different gestalt cues rely on distinct networks in the brain or share a common network. Our study revealed that gestalt grouping involved the inferior parietal cortex, middle temporal gyrus and prefrontal cortex irrespective of the specific cue used. These findings agree with observations in neurological patients, which suggest that inferior parietal regions may aid the integration of local features into a global gestalt. Damage to this region results in simultanagnosia, a deficit in perceiving multiple objects and global scenes.
NASA Astrophysics Data System (ADS)
Alimohammadi, Shahrouz; Cavaglieri, Daniele; Beyhaghi, Pooriya; Bewley, Thomas R.
2016-11-01
This work applies a recently developed Derivative-free optimization algorithm to derive a new mixed implicit-explicit (IMEX) time integration scheme for Computational Fluid Dynamics (CFD) simulations. This algorithm allows imposing a specified order of accuracy for the time integration and other important stability properties in the form of nonlinear constraints within the optimization problem. In this procedure, the coefficients of the IMEX scheme should satisfy a set of constraints simultaneously. Therefore, the optimization process, at each iteration, estimates the location of the optimal coefficients using a set of global surrogates, for both the objective and constraint functions, as well as a model of the uncertainty function of these surrogates based on the concept of Delaunay triangulation. This procedure has been proven to converge to the global minimum of the constrained optimization problem provided the constraints and objective functions are twice differentiable. As a result, a new third-order, low-storage IMEX Runge-Kutta time integration scheme is obtained with remarkably fast convergence. Numerical tests are then performed leveraging the turbulent channel flow simulations to validate the theoretical order of accuracy and stability properties of the new scheme.
A new effective operator for the hybrid algorithm for solving global optimisation problems
NASA Astrophysics Data System (ADS)
Duc, Le Anh; Li, Kenli; Nguyen, Tien Trong; Yen, Vu Minh; Truong, Tung Khac
2018-04-01
Hybrid algorithms have been recently used to solve complex single-objective optimisation problems. The ultimate goal is to find an optimised global solution by using these algorithms. Based on the existing algorithms (HP_CRO, PSO, RCCRO), this study proposes a new hybrid algorithm called MPC (Mean-PSO-CRO), which utilises a new Mean-Search Operator. By employing this new operator, the proposed algorithm improves the search ability on areas of the solution space that the other operators of previous algorithms do not explore. Specifically, the Mean-Search Operator helps find the better solutions in comparison with other algorithms. Moreover, the authors have proposed two parameters for balancing local and global search and between various types of local search, as well. In addition, three versions of this operator, which use different constraints, are introduced. The experimental results on 23 benchmark functions, which are used in previous works, show that our framework can find better optimal or close-to-optimal solutions with faster convergence speed for most of the benchmark functions, especially the high-dimensional functions. Thus, the proposed algorithm is more effective in solving single-objective optimisation problems than the other existing algorithms.
A trust region-based approach to optimize triple response systems
NASA Astrophysics Data System (ADS)
Fan, Shu-Kai S.; Fan, Chihhao; Huang, Chia-Fen
2014-05-01
This article presents a new computing procedure for the global optimization of the triple response system (TRS) where the response functions are non-convex quadratics and the input factors satisfy a radial constrained region of interest. The TRS arising from response surface modelling can be approximated using a nonlinear mathematical program that considers one primary objective function and two secondary constraint functions. An optimization algorithm named the triple response surface algorithm (TRSALG) is proposed to determine the global optimum for the non-degenerate TRS. In TRSALG, the Lagrange multipliers of the secondary functions are determined using the Hooke-Jeeves search method and the Lagrange multiplier of the radial constraint is located using the trust region method within the global optimality space. The proposed algorithm is illustrated in terms of three examples appearing in the quality-control literature. The results of TRSALG compared to a gradient-based method are also presented.
Kassa, Semu Mitiku
2018-02-01
Funds from various global organizations, such as, The Global Fund, The World Bank, etc. are not directly distributed to the targeted risk groups. Especially in the so-called third-world-countries, the major part of the fund in HIV prevention programs comes from these global funding organizations. The allocations of these funds usually pass through several levels of decision making bodies that have their own specific parameters to control and specific objectives to achieve. However, these decisions are made mostly in a heuristic manner and this may lead to a non-optimal allocation of the scarce resources. In this paper, a hierarchical mathematical optimization model is proposed to solve such a problem. Combining existing epidemiological models with the kind of interventions being on practice, a 3-level hierarchical decision making model in optimally allocating such resources has been developed and analyzed. When the impact of antiretroviral therapy (ART) is included in the model, it has been shown that the objective function of the lower level decision making structure is a non-convex minimization problem in the allocation variables even if all the production functions for the intervention programs are assumed to be linear.
NASA Astrophysics Data System (ADS)
Aittokoski, Timo; Miettinen, Kaisa
2008-07-01
Solving real-life engineering problems can be difficult because they often have multiple conflicting objectives, the objective functions involved are highly nonlinear and they contain multiple local minima. Furthermore, function values are often produced via a time-consuming simulation process. These facts suggest the need for an automated optimization tool that is efficient (in terms of number of objective function evaluations) and capable of solving global and multiobjective optimization problems. In this article, the requirements on a general simulation-based optimization system are discussed and such a system is applied to optimize the performance of a two-stroke combustion engine. In the example of a simulation-based optimization problem, the dimensions and shape of the exhaust pipe of a two-stroke engine are altered, and values of three conflicting objective functions are optimized. These values are derived from power output characteristics of the engine. The optimization approach involves interactive multiobjective optimization and provides a convenient tool to balance between conflicting objectives and to find good solutions.
Yamin, Stephanie; Stinchcombe, Arne; Gagnon, Sylvain
2016-06-01
This study sought to predict driving performance of drivers with Alzheimer's disease (AD) using measures of attention, visual processing, and global cognition. Simulated driving performance of individuals with mild AD (n = 20) was contrasted with performance of a group of healthy controls (n = 21). Performance on measures of global cognitive function and specific tests of attention and visual processing were examined in relation to simulated driving performance. Strong associations were observed between measures of attention, notably the Test of Everyday Attention (sustained attention; r = -.651, P = .002) and the Useful Field of View (r = .563, P = .010), and driving performance among drivers with mild AD. The Visual Object and Space Perception Test-object was significantly correlated with the occurrence of crashes (r = .652, P = .002). Tests of global cognition did not correlate with simulated driving outcomes. The results suggest that professionals exercise caution when extrapolating driving performance based on global cognitive indicators. © The Author(s) 2015.
Cui, Wenchao; Wang, Yi; Lei, Tao; Fan, Yangyu; Feng, Yan
2013-01-01
This paper presents a variational level set method for simultaneous segmentation and bias field estimation of medical images with intensity inhomogeneity. In our model, the statistics of image intensities belonging to each different tissue in local regions are characterized by Gaussian distributions with different means and variances. According to maximum a posteriori probability (MAP) and Bayes' rule, we first derive a local objective function for image intensities in a neighborhood around each pixel. Then this local objective function is integrated with respect to the neighborhood center over the entire image domain to give a global criterion. In level set framework, this global criterion defines an energy in terms of the level set functions that represent a partition of the image domain and a bias field that accounts for the intensity inhomogeneity of the image. Therefore, image segmentation and bias field estimation are simultaneously achieved via a level set evolution process. Experimental results for synthetic and real images show desirable performances of our method.
Parameter estimation of a pulp digester model with derivative-free optimization strategies
NASA Astrophysics Data System (ADS)
Seiça, João C.; Romanenko, Andrey; Fernandes, Florbela P.; Santos, Lino O.; Fernandes, Natércia C. P.
2017-07-01
The work concerns the parameter estimation in the context of the mechanistic modelling of a pulp digester. The problem is cast as a box bounded nonlinear global optimization problem in order to minimize the mismatch between the model outputs with the experimental data observed at a real pulp and paper plant. MCSFilter and Simulated Annealing global optimization methods were used to solve the optimization problem. While the former took longer to converge to the global minimum, the latter terminated faster at a significantly higher value of the objective function and, thus, failed to find the global solution.
Hybrid optimization and Bayesian inference techniques for a non-smooth radiation detection problem
Stefanescu, Razvan; Schmidt, Kathleen; Hite, Jason; ...
2016-12-12
In this paper, we propose several algorithms to recover the location and intensity of a radiation source located in a simulated 250 × 180 m block of an urban center based on synthetic measurements. Radioactive decay and detection are Poisson random processes, so we employ likelihood functions based on this distribution. Owing to the domain geometry and the proposed response model, the negative logarithm of the likelihood is only piecewise continuous differentiable, and it has multiple local minima. To address these difficulties, we investigate three hybrid algorithms composed of mixed optimization techniques. For global optimization, we consider simulated annealing, particlemore » swarm, and genetic algorithm, which rely solely on objective function evaluations; that is, they do not evaluate the gradient in the objective function. By employing early stopping criteria for the global optimization methods, a pseudo-optimum point is obtained. This is subsequently utilized as the initial value by the deterministic implicit filtering method, which is able to find local extrema in non-smooth functions, to finish the search in a narrow domain. These new hybrid techniques, combining global optimization and implicit filtering address, difficulties associated with the non-smooth response, and their performances, are shown to significantly decrease the computational time over the global optimization methods. To quantify uncertainties associated with the source location and intensity, we employ the delayed rejection adaptive Metropolis and DiffeRential Evolution Adaptive Metropolis algorithms. Finally, marginal densities of the source properties are obtained, and the means of the chains compare accurately with the estimates produced by the hybrid algorithms.« less
Krityakierne, Tipaluck; Akhtar, Taimoor; Shoemaker, Christine A.
2016-02-02
This paper presents a parallel surrogate-based global optimization method for computationally expensive objective functions that is more effective for larger numbers of processors. To reach this goal, we integrated concepts from multi-objective optimization and tabu search into, single objective, surrogate optimization. Our proposed derivative-free algorithm, called SOP, uses non-dominated sorting of points for which the expensive function has been previously evaluated. The two objectives are the expensive function value of the point and the minimum distance of the point to previously evaluated points. Based on the results of non-dominated sorting, P points from the sorted fronts are selected as centersmore » from which many candidate points are generated by random perturbations. Based on surrogate approximation, the best candidate point is subsequently selected for expensive evaluation for each of the P centers, with simultaneous computation on P processors. Centers that previously did not generate good solutions are tabu with a given tenure. We show almost sure convergence of this algorithm under some conditions. The performance of SOP is compared with two RBF based methods. The test results show that SOP is an efficient method that can reduce time required to find a good near optimal solution. In a number of cases the efficiency of SOP is so good that SOP with 8 processors found an accurate answer in less wall-clock time than the other algorithms did with 32 processors.« less
Local blur analysis and phase error correction method for fringe projection profilometry systems.
Rao, Li; Da, Feipeng
2018-05-20
We introduce a flexible error correction method for fringe projection profilometry (FPP) systems in the presence of local blur phenomenon. Local blur caused by global light transport such as camera defocus, projector defocus, and subsurface scattering will cause significant systematic errors in FPP systems. Previous methods, which adopt high-frequency patterns to separate the direct and global components, fail when the global light phenomenon occurs locally. In this paper, the influence of local blur on phase quality is thoroughly analyzed, and a concise error correction method is proposed to compensate the phase errors. For defocus phenomenon, this method can be directly applied. With the aid of spatially varying point spread functions and local frontal plane assumption, experiments show that the proposed method can effectively alleviate the system errors and improve the final reconstruction accuracy in various scenes. For a subsurface scattering scenario, if the translucent object is dominated by multiple scattering, the proposed method can also be applied to correct systematic errors once the bidirectional scattering-surface reflectance distribution function of the object material is measured.
Adjuvant ovarian function suppression and cognitive function in women with breast cancer
Phillips, Kelly-Anne; Regan, Meredith M; Ribi, Karin; Francis, Prudence A; Puglisi, Fabio; Bellet, Meritxell; Spazzapan, Simon; Karlsson, Per; Budman, Daniel R; Zaman, Khalil; Abdi, Ehtesham A; Domchek, Susan M; Feng, Yang; Price, Karen N; Coates, Alan S; Gelber, Richard D; Maruff, Paul; Boyle, Frances; Forbes, John F; Ahles, Tim; Fleming, Gini F; Bernhard, Jürg
2016-01-01
Background: To examine the effect on cognitive function of adjuvant ovarian function suppression (OFS) for breast cancer. Methods: The Suppression of Ovarian Function (SOFT) trial randomised premenopausal women with hormone receptor-positive breast cancer to 5 years adjuvant endocrine therapy with tamoxifen+OFS, exemestane+OFS or tamoxifen alone. The Co-SOFT substudy assessed objective cognitive function and patient reported outcomes at randomisation (T0), and 1 year later (T1); the primary endpoint was change in global cognitive function, measured by the composite objective cognitive function score. Data were compared for the pooled tamoxifen+OFS and exemestane+OFS groups vs the tamoxifen alone group using the Wilcoxon rank-sum test. Results: Of 86 participants, 74 underwent both T0 and T1 cognitive testing; 54 randomised to OFS+ either tamoxifen (28) or exemestane (26) and 20 randomised to tamoxifen alone. There was no significant difference in the changes in the composite cognitive function scores between the OFS+ tamoxifen or exemestane groups and the tamoxifen group (mean±s.d., −0.21±0.92 vs −0.04±0.49, respectively, P=0.71, effect size=−0.20), regardless of prior chemotherapy status, and adjusting for baseline characteristics. Conclusions: The Co-SOFT study, although limited by small samples size, provides no evidence that adding OFS to adjuvant oral endocrine therapy substantially affects global cognitive function. PMID:27092785
Reduced integration and improved segregation of functional brain networks in Alzheimer’s disease
NASA Astrophysics Data System (ADS)
Kabbara, A.; Eid, H.; El Falou, W.; Khalil, M.; Wendling, F.; Hassan, M.
2018-04-01
Objective. Emerging evidence shows that cognitive deficits in Alzheimer’s disease (AD) are associated with disruptions in brain functional connectivity. Thus, the identification of alterations in AD functional networks has become a topic of increasing interest. However, to what extent AD induces disruption of the balance of local and global information processing in the human brain remains elusive. The main objective of this study is to explore the dynamic topological changes of AD networks in terms of brain network segregation and integration. Approach. We used electroencephalography (EEG) data recorded from 20 participants (10 AD patients and 10 healthy controls) during resting state. Functional brain networks were reconstructed using EEG source connectivity computed in different frequency bands. Graph theoretical analyses were performed assess differences between both groups. Main results. Results revealed that AD networks, compared to networks of age-matched healthy controls, are characterized by lower global information processing (integration) and higher local information processing (segregation). Results showed also significant correlation between the alterations in the AD patients’ functional brain networks and their cognitive scores. Significance. These findings may contribute to the development of EEG network-based test that could strengthen results obtained from currently-used neurophysiological tests in neurodegenerative diseases.
Brain tissue volumes in relation to cognitive function and risk of dementia.
Ikram, M Arfan; Vrooman, Henri A; Vernooij, Meike W; den Heijer, Tom; Hofman, Albert; Niessen, Wiro J; van der Lugt, Aad; Koudstaal, Peter J; Breteler, Monique M B
2010-03-01
We investigated in a population-based cohort study the association of global and lobar brain tissue volumes with specific cognitive domains and risk of dementia. Participants (n=490; 60-90 years) were non-demented at baseline (1995-1996). From baseline brain MRI-scans we obtained global and lobar volumes of CSF, GM, normal WM, white matter lesions and hippocampus. We performed neuropsychological testing at baseline to assess information processing speed, executive function, memory function and global cognitive function. Participants were followed for incident dementia until January 1, 2005. Larger volumes of CSF and WML were associated with worse performance on all neuropsychological tests, and an increased risk of dementia. Smaller WM volume was related to poorer information processing speed and executive function. In contrast, smaller GM volume was associated with worse memory function and increased risk of dementia. When investigating lobar GM volumes, we found that hippocampal volume and temporal GM volume were most strongly associated with risk of dementia, even in persons without objective and subjective cognitive deficits at baseline, followed by frontal and parietal GM volumes. Copyright 2008 Elsevier Inc. All rights reserved.
Psychosocial Development of 5-year-old Children with Hearing Loss: Risks and protective factors
Wong, Cara L.; Ching, Teresa YC; Leigh, Greg; Cupples, Linda; Button, Laura; Marnane, Vivienne; Whitfield, Jessica; Gunnourie, Miriam; Martin, Louise
2016-01-01
Objective The aims of this paper were to report on the global psychosocial functioning of 5-year-old DHH children and examine the risk and protective factors that predict outcomes. Design A cross-sectional analysis of data collected from a prospective, population-based longitudinal study. Study Sample Parents/caregivers of 356 children completed questionnaires on psychosocial development (CDI, SDQ), functional communication (PEACH) and demographic information. Children completed standardised assessments of non-verbal cognitive ability (WNV) and language (PLS-4). Results On average, global psychosocial functioning was within the range of typically developing children; however, variability was high and 12% of children had scores that were more than 2 SDs below the norm. Non-verbal cognitive ability, presence of additional disabilities, language and functional communication significantly predicted outcomes. In contrast, type of hearing device, severity of hearing loss and age at intervention did not. Conclusion The global psychosocial functioning of this cohort of 5-year-old DHH children fell within the range of typically developing children. . The findings suggest that spoken language ability and functional communication skills are vital for healthy psychosocial development. PMID:27541363
A Numerical Optimization Approach for Tuning Fuzzy Logic Controllers
NASA Technical Reports Server (NTRS)
Woodard, Stanley E.; Garg, Devendra P.
1998-01-01
This paper develops a method to tune fuzzy controllers using numerical optimization. The main attribute of this approach is that it allows fuzzy logic controllers to be tuned to achieve global performance requirements. Furthermore, this approach allows design constraints to be implemented during the tuning process. The method tunes the controller by parameterizing the membership functions for error, change-in-error and control output. The resulting parameters form a design vector which is iteratively changed to minimize an objective function. The minimal objective function results in an optimal performance of the system. A spacecraft mounted science instrument line-of-sight pointing control is used to demonstrate results.
Fast global image smoothing based on weighted least squares.
Min, Dongbo; Choi, Sunghwan; Lu, Jiangbo; Ham, Bumsub; Sohn, Kwanghoon; Do, Minh N
2014-12-01
This paper presents an efficient technique for performing a spatially inhomogeneous edge-preserving image smoothing, called fast global smoother. Focusing on sparse Laplacian matrices consisting of a data term and a prior term (typically defined using four or eight neighbors for 2D image), our approach efficiently solves such global objective functions. In particular, we approximate the solution of the memory-and computation-intensive large linear system, defined over a d-dimensional spatial domain, by solving a sequence of 1D subsystems. Our separable implementation enables applying a linear-time tridiagonal matrix algorithm to solve d three-point Laplacian matrices iteratively. Our approach combines the best of two paradigms, i.e., efficient edge-preserving filters and optimization-based smoothing. Our method has a comparable runtime to the fast edge-preserving filters, but its global optimization formulation overcomes many limitations of the local filtering approaches. Our method also achieves high-quality results as the state-of-the-art optimization-based techniques, but runs ∼10-30 times faster. Besides, considering the flexibility in defining an objective function, we further propose generalized fast algorithms that perform Lγ norm smoothing (0 < γ < 2) and support an aggregated (robust) data term for handling imprecise data constraints. We demonstrate the effectiveness and efficiency of our techniques in a range of image processing and computer graphics applications.
2014-12-26
additive value function, which assumes mutual preferential independence (Gregory S. Parnell, 2013). In other words, this method can be used if the... additive value function method to calculate the aggregate value of multiple objectives. Step 9 : Sensitivity Analysis Once the global values are...gravity metric, the additive method will be applied using equal weights for each axis value function. Pilot Satisfaction (Usability) As expressed
Shen, Peiping; Zhang, Tongli; Wang, Chunfeng
2017-01-01
This article presents a new approximation algorithm for globally solving a class of generalized fractional programming problems (P) whose objective functions are defined as an appropriate composition of ratios of affine functions. To solve this problem, the algorithm solves an equivalent optimization problem (Q) via an exploration of a suitably defined nonuniform grid. The main work of the algorithm involves checking the feasibility of linear programs associated with the interesting grid points. It is proved that the proposed algorithm is a fully polynomial time approximation scheme as the ratio terms are fixed in the objective function to problem (P), based on the computational complexity result. In contrast to existing results in literature, the algorithm does not require the assumptions on quasi-concavity or low-rank of the objective function to problem (P). Numerical results are given to illustrate the feasibility and effectiveness of the proposed algorithm.
Comparing Pixel- and Object-Based Approaches in Effectively Classifying Wetland-Dominated Landscapes
Wetland ecosystems straddle both terrestrial and aquatic habitats, performing many ecological functions directly and indirectly benefitting humans. However, global wetland losses are substantial. Satellite remote sensing and classification informs wise wetland management and moni...
NASA Astrophysics Data System (ADS)
Bortolozo, Cassiano Antonio; Bokhonok, Oleg; Porsani, Jorge Luís; Monteiro dos Santos, Fernando Acácio; Diogo, Liliana Alcazar; Slob, Evert
2017-11-01
Ambiguities in geophysical inversion results are always present. How these ambiguities appear in most cases open to interpretation. It is interesting to investigate ambiguities with regard to the parameters of the models under study. Residual Function Dispersion Map (RFDM) can be used to differentiate between global ambiguities and local minima in the objective function. We apply RFDM to Vertical Electrical Sounding (VES) and TEM Sounding inversion results. Through topographic analysis of the objective function we evaluate the advantages and limitations of electrical sounding data compared with TEM sounding data, and the benefits of joint inversion in comparison with the individual methods. The RFDM analysis proved to be a very interesting tool for understanding the joint inversion method of VES/TEM. Also the advantage of the applicability of the RFDM analyses in real data is explored in this paper to demonstrate not only how the objective function of real data behaves but the applicability of the RFDM approach in real cases. With the analysis of the results, it is possible to understand how the joint inversion can reduce the ambiguity of the methods.
Heo, Eun Young; Hwang, Hee; Kim, Eun Hye; Cho, Eun Young; Lee, Kee Hyuck; Kim, Tae Hun; Kim, Ki Dong; Baek, Rong Min
2012-01-01
Objectives This study aims to investigate the suitability of electronic health record (EHR) systems in Korea for global certification and to propose functions for future global systems by comparing and analyzing the certification criteria for Certification Commission for Health Information Technology (CCHIT) Certified Ambulatory EHR with BESTCare, which is the EHR system at Seoul National University Bundang hospital. Methods Domain expert groups were formed to analyze the inclusion of BESTCare functions and the types of differences for each of the CCHIT Certified 2011 Ambulatory EHR Certification Criteria. The types of differences were divided into differences in functions (F), differences in business processes (B), and differences in government policies (P). Results Generally, the criteria that showed differences in functions pertained to the connection between the diagnosis/problem list and order, the alert and warning functions for medication-diagnosis interactions, and the reminder/instruction/notification messages related to the patient's immunization status; these absent functions were enhanced clinical decision support system (CDSS) functions related to patient safety and healthcare quality. Differences in government policies were found in the pharmacy's electronic prescription functions, while differences in business processes were found in the functions constrained by the local workflow or internal policy, which require some customization. Conclusions Functions that differed between the CCHIT certification criteria and the BESTCare system in this study should be considered when developing a global EHR system. Such a system will need to be easily customizable to adapt to various government policies and local business processes. These functions should be considered when developing a global EHR system certified by CCHIT in the future. PMID:22509474
Depp, Colin A; Harmell, Alexandrea L; Vahia, Ipsit V; Mausbach, Brent T
2016-01-01
Our objective was to examine the association of mobile phone use and ownership with psychopathology, cognitive functioning, and functional outcome in 196 outpatients aged 40 years and older who were diagnosed with schizophrenia. Participants reported their past and current mobile phone use on a standardized self-report scale and they were administered tests of global cognition, functional capacity, and informant-rated functional outcome. The great majority of subjects had used a mobile phone (78%) but few currently owned one (27%). After adjusting for age (mean age 51), any past mobile phone use was associated with less severe negative symptoms, and higher global cognitive performance, functional capacity, and functional outcome. A total of 60% of participants reported being comfortable with mobile phones, but comfort was not associated with any cognitive or functional outcomes. Most of the older patients with schizophrenia have used mobile phones and lifetime mobile phone use is a positive indicator of cognitive and functional status.
Hormonal therapy is associated with better self-esteem, mood, and quality of life in transsexuals.
Gorin-Lazard, Audrey; Baumstarck, Karine; Boyer, Laurent; Maquigneau, Aurélie; Penochet, Jean-Claude; Pringuey, Dominique; Albarel, Frédérique; Morange, Isabelle; Bonierbale, Mireille; Lançon, Christophe; Auquier, Pascal
2013-11-01
Few studies have assessed the role of cross-sex hormones on psychological outcomes during the period of hormonal therapy preceding sex reassignment surgery in transsexuals. The objective of this study was to assess the relationship between hormonal therapy, self-esteem, depression, quality of life (QoL), and global functioning. This study incorporated a cross-sectional design. The inclusion criteria were diagnosis of gender identity disorder (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision) and inclusion in a standardized sex reassignment procedure. The outcome measures were self-esteem (Social Self-Esteem Inventory), mood (Beck Depression Inventory), QoL (Subjective Quality of Life Analysis), and global functioning (Global Assessment of Functioning). Sixty-seven consecutive individuals agreed to participate. Seventy-three percent received hormonal therapy. Hormonal therapy was an independent factor in greater self-esteem, less severe depression symptoms, and greater "psychological-like" dimensions of QoL. These findings should provide pertinent information for health care providers who consider this period as a crucial part of the global sex reassignment procedure.
Robust active contour via additive local and global intensity information based on local entropy
NASA Astrophysics Data System (ADS)
Yuan, Shuai; Monkam, Patrice; Zhang, Feng; Luan, Fangjun; Koomson, Ben Alfred
2018-01-01
Active contour-based image segmentation can be a very challenging task due to many factors such as high intensity inhomogeneity, presence of noise, complex shape, weak boundaries objects, and dependence on the position of the initial contour. We propose a level set-based active contour method to segment complex shape objects from images corrupted by noise and high intensity inhomogeneity. The energy function of the proposed method results from combining the global intensity information and local intensity information with some regularization factors. First, the global intensity term is proposed based on a scheme formulation that considers two intensity values for each region instead of one, which outperforms the well-known Chan-Vese model in delineating the image information. Second, the local intensity term is formulated based on local entropy computed considering the distribution of the image brightness and using the generalized Gaussian distribution as the kernel function. Therefore, it can accurately handle high intensity inhomogeneity and noise. Moreover, our model is not dependent on the position occupied by the initial curve. Finally, extensive experiments using various images have been carried out to illustrate the performance of the proposed method.
Lin, Chun-Yuan; Liang, Sun-Yuan; Chang, Yue-Cune; Ting, Shuo-Yen; Kao, Ching-Ling; Wu, Yu-Hsin; Tsai, Guochuan E; Lane, Hsien-Yuan
2017-08-01
Objectives Hypofunction of NMDA receptor is implicated in the pathophysiology, particularly cognitive impairment, of schizophrenia. Sarcosine, a glycine transporter I (GlyT-1) inhibitor, and sodium benzoate, a d-amino acid oxidase (DAAO) inhibitor, can both enhance NMDA receptor-mediated neurotransmission. We proposed simultaneously inhibiting DAAO and GlyT-1 may be more effective than inhibition of either in improving the cognitive and global functioning of schizophrenia patients. Methods This study compared add-on sarcosine (2 g/day) plus benzoate (1 g/day) vs. sarcosine (2 g/day) for the clinical symptoms, as well as the cognitive and global functioning, of chronic schizophrenia patients in a 12-week, double-blind, randomised, placebo-controlled trial. Participants were measured with the Positive and Negative Syndrome Scale and the Global Assessment of Functioning Scale every 3 weeks. Seven cognitive domains, recommended by the Measurement and Treatment Research to Improve Cognition in Schizophrenia Committee, were measured at weeks 0 and 12. Results Adjunctive sarcosine plus benzoate, but not sarcosine alone, improved the cognitive and global functioning of patients with schizophrenia, even when their clinical symptoms had not improved. Conclusions This finding suggests N-methyl-d-aspartate receptor-enhancement therapy can improve the cognitive function of patients with schizophrenia, further indicating this pro-cognitive effect can be primary without improvement in clinical symptoms.
Clarke, Robert; Bennett, Derrick; Parish, Sarah; Lewington, Sarah; Skeaff, Murray; Eussen, Simone JPM; Lewerin, Catharina; Stott, David J; Armitage, Jane; Hankey, Graeme J; Lonn, Eva; Spence, J David; Galan, Pilar; de Groot, Lisette C; Halsey, Jim; Dangour, Alan D; Collins, Rory; Grodstein, Francine
2014-01-01
Background: Elevated plasma homocysteine is a risk factor for Alzheimer disease, but the relevance of homocysteine lowering to slow the rate of cognitive aging is uncertain. Objective: The aim was to assess the effects of treatment with B vitamins compared with placebo, when administered for several years, on composite domains of cognitive function, global cognitive function, and cognitive aging. Design: A meta-analysis was conducted by using data combined from 11 large trials in 22,000 participants. Domain-based z scores (for memory, speed, and executive function and a domain-composite score for global cognitive function) were available before and after treatment (mean duration: 2.3 y) in the 4 cognitive-domain trials (1340 individuals); Mini-Mental State Examination (MMSE)–type tests were available at the end of treatment (mean duration: 5 y) in the 7 global cognition trials (20,431 individuals). Results: The domain-composite and MMSE-type global cognitive function z scores both decreased with age (mean ± SE: −0.054 ± 0.004 and −0.036 ± 0.001/y, respectively). Allocation to B vitamins lowered homocysteine concentrations by 28% in the cognitive-domain trials but had no significant effects on the z score differences from baseline for individual domains or for global cognitive function (z score difference: 0.00; 95% CI: −0.05, 0.06). Likewise, allocation to B vitamins lowered homocysteine by 26% in the global cognition trials but also had no significant effect on end-treatment MMSE-type global cognitive function (z score difference: −0.01; 95% CI: −0.03, 0.02). Overall, the effect of a 25% reduction in homocysteine equated to 0.02 y (95% CI: −0.10, 0.13 y) of cognitive aging per year and excluded reductions of >1 mo per year of treatment. Conclusion: Homocysteine lowering by using B vitamins had no significant effect on individual cognitive domains or global cognitive function or on cognitive aging. PMID:24965307
Recursive Branching Simulated Annealing Algorithm
NASA Technical Reports Server (NTRS)
Bolcar, Matthew; Smith, J. Scott; Aronstein, David
2012-01-01
This innovation is a variation of a simulated-annealing optimization algorithm that uses a recursive-branching structure to parallelize the search of a parameter space for the globally optimal solution to an objective. The algorithm has been demonstrated to be more effective at searching a parameter space than traditional simulated-annealing methods for a particular problem of interest, and it can readily be applied to a wide variety of optimization problems, including those with a parameter space having both discrete-value parameters (combinatorial) and continuous-variable parameters. It can take the place of a conventional simulated- annealing, Monte-Carlo, or random- walk algorithm. In a conventional simulated-annealing (SA) algorithm, a starting configuration is randomly selected within the parameter space. The algorithm randomly selects another configuration from the parameter space and evaluates the objective function for that configuration. If the objective function value is better than the previous value, the new configuration is adopted as the new point of interest in the parameter space. If the objective function value is worse than the previous value, the new configuration may be adopted, with a probability determined by a temperature parameter, used in analogy to annealing in metals. As the optimization continues, the region of the parameter space from which new configurations can be selected shrinks, and in conjunction with lowering the annealing temperature (and thus lowering the probability for adopting configurations in parameter space with worse objective functions), the algorithm can converge on the globally optimal configuration. The Recursive Branching Simulated Annealing (RBSA) algorithm shares some features with the SA algorithm, notably including the basic principles that a starting configuration is randomly selected from within the parameter space, the algorithm tests other configurations with the goal of finding the globally optimal solution, and the region from which new configurations can be selected shrinks as the search continues. The key difference between these algorithms is that in the SA algorithm, a single path, or trajectory, is taken in parameter space, from the starting point to the globally optimal solution, while in the RBSA algorithm, many trajectories are taken; by exploring multiple regions of the parameter space simultaneously, the algorithm has been shown to converge on the globally optimal solution about an order of magnitude faster than when using conventional algorithms. Novel features of the RBSA algorithm include: 1. More efficient searching of the parameter space due to the branching structure, in which multiple random configurations are generated and multiple promising regions of the parameter space are explored; 2. The implementation of a trust region for each parameter in the parameter space, which provides a natural way of enforcing upper- and lower-bound constraints on the parameters; and 3. The optional use of a constrained gradient- search optimization, performed on the continuous variables around each branch s configuration in parameter space to improve search efficiency by allowing for fast fine-tuning of the continuous variables within the trust region at that configuration point.
Cheng, Qiang; Zhou, Hongbo; Cheng, Jie
2011-06-01
Selecting features for multiclass classification is a critically important task for pattern recognition and machine learning applications. Especially challenging is selecting an optimal subset of features from high-dimensional data, which typically have many more variables than observations and contain significant noise, missing components, or outliers. Existing methods either cannot handle high-dimensional data efficiently or scalably, or can only obtain local optimum instead of global optimum. Toward the selection of the globally optimal subset of features efficiently, we introduce a new selector--which we call the Fisher-Markov selector--to identify those features that are the most useful in describing essential differences among the possible groups. In particular, in this paper we present a way to represent essential discriminating characteristics together with the sparsity as an optimization objective. With properly identified measures for the sparseness and discriminativeness in possibly high-dimensional settings, we take a systematic approach for optimizing the measures to choose the best feature subset. We use Markov random field optimization techniques to solve the formulated objective functions for simultaneous feature selection. Our results are noncombinatorial, and they can achieve the exact global optimum of the objective function for some special kernels. The method is fast; in particular, it can be linear in the number of features and quadratic in the number of observations. We apply our procedure to a variety of real-world data, including mid--dimensional optical handwritten digit data set and high-dimensional microarray gene expression data sets. The effectiveness of our method is confirmed by experimental results. In pattern recognition and from a model selection viewpoint, our procedure says that it is possible to select the most discriminating subset of variables by solving a very simple unconstrained objective function which in fact can be obtained with an explicit expression.
Dang, C; Xu, L
2001-03-01
In this paper a globally convergent Lagrange and barrier function iterative algorithm is proposed for approximating a solution of the traveling salesman problem. The algorithm employs an entropy-type barrier function to deal with nonnegativity constraints and Lagrange multipliers to handle linear equality constraints, and attempts to produce a solution of high quality by generating a minimum point of a barrier problem for a sequence of descending values of the barrier parameter. For any given value of the barrier parameter, the algorithm searches for a minimum point of the barrier problem in a feasible descent direction, which has a desired property that the nonnegativity constraints are always satisfied automatically if the step length is a number between zero and one. At each iteration the feasible descent direction is found by updating Lagrange multipliers with a globally convergent iterative procedure. For any given value of the barrier parameter, the algorithm converges to a stationary point of the barrier problem without any condition on the objective function. Theoretical and numerical results show that the algorithm seems more effective and efficient than the softassign algorithm.
Ventura, Joseph; Cienfuegos, Angel; Boxer, Oren; Bilder, Robert
2008-11-01
Cognitive deficits are core features of schizophrenia that have been associated reliably with functional outcomes and now are a focus of treatment research. New rating scales are needed to complement current psychometric testing procedures, both to enable wider clinical use, and to serve as endpoints in clinical trials. Subjects were 35 schizophrenia patient-and-caregiver pairs recruited from the UCLA and West Los Angeles VA Outpatient Psychiatry Departments. Participants were assessed with the Clinical Global Impression of Cognition in Schizophrenia (CGI-CogS), an interview-based rating scale of cognitive functioning, on 3 occasions (baseline, 1 month, and 3 months). A computerized neurocognitive battery (Cogtest), an assessment of functioning, and symptom measures were administered at two occasions (baseline and one month). The CGI-CogS ratings generally showed a high level of internal consistency (Cronbach's alpha=.69 to .96), adequate levels of inter-rater reliability (ICC's=.71 to .80), and high test-retest stability (ICC's=.92 to .95). Correlations of caregiver and rater global (but not "patient only rating") CGI-CogS ratings with neurocognitive performance were in the moderate range (r's=-.27 to -.48), while most of the correlations with functional outcome were moderate to high (r's=-.41 to -.72). In fact, the CGI-CogS ratings were significantly more correlated with Social Functioning than were objective neurocognitive test scores (p=.02) and showed a trend in the same direction for predicting Instrumental Functioning (p=.06). We found moderate correlations between CGI-CogS global ratings and PANSS positive (r's=.36 to .49) and SANS negative symptoms (r=.41 to .61), but not with BPRS depression (r's=.11 to .13). An interview-based measure of cognition demonstrated high internal consistency, good inter-rater reliability, and high test-retest reliability. Caregiver ratings appear to add important clinical information over patient-only ratings. The CGI-CogS showed moderate validity with respect to neurocognitive performance and functional outcome, and correlations of CGI-CogS with functional outcomes were stronger than correlations of objective neurocognitive performance with functional outcomes. The CGI-CogS appears to offer a reliable and valid method for clinical rating of cognitive deficits and their impact on everyday functioning in schizophrenia.
Girardi, Paolo; Del Casale, Antonio; Rapinesi, Chiara; Kotzalidis, Georgios D; Splendori, Francesca; Verzura, Claudio; Trovini, Giada; Sorice, Serena; Carrus, Dario; Mancinelli, Iginia; Comparelli, Anna; De Filippis, Sergio; Francomano, Antonio; Ballerini, Andrea; Marcellusi, Andrea; Mennini, Francesco S; Ducci, Giuseppe; Sani, Gabriele; Pompili, Maurizio; Brugnoli, Roberto
2018-05-01
Long-acting injectable (LAI) antipsychotics can improve medication adherence and reduce hospitalisation rates compared with oral treatments. Paliperidone palmitate (PAL) and aripiprazole monohydrate (ARI) LAI treatments were associated with improvements in global functioning in patients with schizophrenia. The objective of this study was to assess the predictive factors of better overall functioning in patients with chronic schizophrenia and schizoaffective disorder treated with PAL and ARI. Enrolled were 143 (97 males, 46 females, mean age 38.24 years, SD = 12.65) patients with a diagnosis of schizophrenia or schizoaffective disorder, whom we allocated in two groups (PAL and ARI treatments). We assessed global functioning, amount of oral medications, adherence to oral treatment, and number of hospitalisations before LAI introduction and at assessment time point. Longer treatment time with LAIs (p < .001), lower number of oral drugs (p < .001), and hospitalisations (p = .002) before LAI introduction, and shorter duration of illness (p = .038) predicted better Global Assessment of Functioning scores in the whole sample (R 2 = 0.337). Early administration and longer duration of ARI or PAL treatments could play a significant role in improving global functioning of patients with schizophrenia and schizoaffective disorder. Better improvement in functioning could be achieved with ARI in young individuals with recent illness onset and PAL in patients at risk for recurrent hospitalisations. Copyright © 2018 John Wiley & Sons, Ltd.
Alternate Waveforms for a Low-Cost Civil Global Positioning System Receiver
DOT National Transportation Integrated Search
1980-06-01
This report examines the technical feasibility of alternate waveforms to perform the GPS functions and to result in less complex receivers than is possible with the GPS C/A waveform. The approach taken to accomplish this objective is (a) to identify,...
Quality of Life and Nutritional Status Among Cancer Patients on Chemotherapy
Vergara, Nunilon; Montoya, Jose Enrique; Luna, Herdee Gloriane; Amparo, Jose Roberto; Cristal-Luna, Gloria
2013-01-01
Objectives Malnutrition is prevalent among cancer patients, and maybe correlated with altered quality of life. The objective of this study is to determine wether quality of life among cancer patients on chemotherapy at the National Kidney and Transplant Institute- Cancer Unit differs from patients with normal nutrition based on the Subjective Global Assessment scale. Methods A cross sectional study was conducted among cancer patients admitted for chemotherapy at the National Kidney and Transplant Institute-Cancer Unit from January to May 2011. Demographic profile, performance status by Eastern Cooperative Oncology Group performance scale, nutritional status assessment by Subjective Global Assessment, and quality of life assessment by the European Organization for Research and Treatment of Cancer QoL-30 core module were obtained. Descriptive statistics and ANOVA were performed for analysis of quality of life parameters and nutritional status. Results A total of 97 subjects were included in this study, 66 subjects (68.04%) were females and 31 (31.96%) were males. Mean age was 54.55 ± 11.14 years, while mean performance status by the Eastern Cooperative Oncology Group classification was 0.88 ± 0.83 with a range of 0-3. According to the Subjective Global Assessment, there were 58 patients with SGA A, classified to have adequate nutrition, and 39 patients (40.21%) were considered malnourished. Among these 39 patients, 32 were classified SGA-B (moderately malnourished) and 7 were classified SGA C (severely malnourished) mean global quality of life was 68.73 ± 19.05. Results from ANOVA test revealed that patients were statistically different across the Subjective Global Assessment groups according to global quality of life (p<0.001), physical (p<0.001), role (p<0.001), emotional (p<0.001), and cognitive functioning (p<0.001); fatigue (p<0.001), nausea and vomiting (p<0.001), pain (p<0.001), insomnia (p<0.001), and appetite loss (p<0.001). Conclusion Global quality of life and its parameters: physical state, role, emotional state, cognitive functioning, cancer fatigue, nausea and vomiting, pain, insomnia, and loss of appetite were statistically different across all Subjective Global Assessment groups. Moreover, there was no difference between financial difficulties, social functioning, constipation and diarrhea among the Subjective Global Assessment groups. PMID:23904921
Multiobjective optimization in structural design with uncertain parameters and stochastic processes
NASA Technical Reports Server (NTRS)
Rao, S. S.
1984-01-01
The application of multiobjective optimization techniques to structural design problems involving uncertain parameters and random processes is studied. The design of a cantilever beam with a tip mass subjected to a stochastic base excitation is considered for illustration. Several of the problem parameters are assumed to be random variables and the structural mass, fatigue damage, and negative of natural frequency of vibration are considered for minimization. The solution of this three-criteria design problem is found by using global criterion, utility function, game theory, goal programming, goal attainment, bounded objective function, and lexicographic methods. It is observed that the game theory approach is superior in finding a better optimum solution, assuming the proper balance of the various objective functions. The procedures used in the present investigation are expected to be useful in the design of general dynamic systems involving uncertain parameters, stochastic process, and multiple objectives.
Building a global business continuity programme.
Lazcano, Michael
2014-01-01
Business continuity programmes provide an important function within organisations, especially when aligned with and supportive of the organisation's goals, objectives and organisational culture. Continuity programmes for large, complex international organisations, unlike those for compact national companies, are more difficult to design, build, implement and maintain. Programmes for international organisations require attention to structural design, support across organisational leadership and hierarchy, seamless integration with the organisation's culture, measured success and demonstrated value. This paper details practical, but sometimes overlooked considerations for building successful global business continuity programmes.
SortNet: learning to rank by a neural preference function.
Rigutini, Leonardo; Papini, Tiziano; Maggini, Marco; Scarselli, Franco
2011-09-01
Relevance ranking consists in sorting a set of objects with respect to a given criterion. However, in personalized retrieval systems, the relevance criteria may usually vary among different users and may not be predefined. In this case, ranking algorithms that adapt their behavior from users' feedbacks must be devised. Two main approaches are proposed in the literature for learning to rank: the use of a scoring function, learned by examples, that evaluates a feature-based representation of each object yielding an absolute relevance score, a pairwise approach, where a preference function is learned to determine the object that has to be ranked first in a given pair. In this paper, we present a preference learning method for learning to rank. A neural network, the comparative neural network (CmpNN), is trained from examples to approximate the comparison function for a pair of objects. The CmpNN adopts a particular architecture designed to implement the symmetries naturally present in a preference function. The learned preference function can be embedded as the comparator into a classical sorting algorithm to provide a global ranking of a set of objects. To improve the ranking performances, an active-learning procedure is devised, that aims at selecting the most informative patterns in the training set. The proposed algorithm is evaluated on the LETOR dataset showing promising performances in comparison with other state-of-the-art algorithms.
Magnified gradient function with deterministic weight modification in adaptive learning.
Ng, Sin-Chun; Cheung, Chi-Chung; Leung, Shu-Hung
2004-11-01
This paper presents two novel approaches, backpropagation (BP) with magnified gradient function (MGFPROP) and deterministic weight modification (DWM), to speed up the convergence rate and improve the global convergence capability of the standard BP learning algorithm. The purpose of MGFPROP is to increase the convergence rate by magnifying the gradient function of the activation function, while the main objective of DWM is to reduce the system error by changing the weights of a multilayered feedforward neural network in a deterministic way. Simulation results show that the performance of the above two approaches is better than BP and other modified BP algorithms for a number of learning problems. Moreover, the integration of the above two approaches forming a new algorithm called MDPROP, can further improve the performance of MGFPROP and DWM. From our simulation results, the MDPROP algorithm always outperforms BP and other modified BP algorithms in terms of convergence rate and global convergence capability.
Beyond the Global Assessment of Functioning: Learning From Virginia Apgar
Dimsdale, Joel E.; Jeste, Dilip V.; Patterson, Thomas L.
2011-01-01
Background The Global Assessment of Functioning (GAF) scale is widely used in psychiatry, yet it has certain drawbacks. Objective The authors seek to generate further discussion and research around developing an improved successor to the GAF. Method The authors used the Apgar scale as a template for constructing a possible successor to the GAF. Consulting with 16 colleagues, they selected 5 domains that were felt to be central to functioning in psychiatric patients. Psychiatrists in diverse clinical settings then completed both a GAF and a Psychiatric Apgar scale on 40 patients. Results The two scales were found to agree significantly. Use of the Psychiatric Apgar, however, provides clearer guidance about assessing functioning. Conclusion The GAF was a brilliant addition to psychiatric practice. As we develop the next Diagnostic and Statistical Manual, it is pertinent to ask whether the GAF approach could be optimized even further by applying the lessons of Virginia Apgar. PMID:21051684
The mental functioning axis of the psychodynamic diagnostic manual: an adolescent case study.
Porcerelli, John H; Cogan, Rosemary; Bambery, Michael
2011-03-01
We describe the assessment of a troubled adolescent boy to demonstrate the use of the Shedler-Westen Assessment Profile for Adolescents (Westen, Dutra, & Shedler, 2005) and the Social Cognition and Object Relations Scale-Global (Westen, 1995) to formulate the Mental Functioning for Children and Adolescents Axis (MCA) of the Psychodynamic Diagnostic Manual (PDM Task Force, 2006). The assessment made possible a meaningful psychodynamic therapy.
The Flora Mission for Ecosystem Composition, Disturbance and Productivity
NASA Technical Reports Server (NTRS)
Asner, Gregory P.; Knox, Robert G.; Green, Robert O.; Ungar, Stephen G.
2005-01-01
Global land use and climate variability alter ecosystem conditions - including structure, function, and biological diversity - at a pace that requires unambiguous observations from satellite vantage points. Current global measurements are limited to general land cover, some disturbances, vegetation leaf area index, and canopy energy absorption. Flora is a pathfinding mission that provides new measurements of ecosystem structure, function, and diversity to understand the spatial and temporal dynamics of human and natural disturbances, and the biogeochemical and physiological responses of ecosystems to disturbance. The mission relies upon high-fidelity imaging spectroscopy to deliver full optical spectrum measurements (400-2500 nm) of the global land surface on a monthly time step at 45 meter spatial resolution for three years. The Flora measurement objectives are: (i) fractional cover of biological materials, (ii) canopy water content, (iii) vegetation pigments and light-use efficiency, (iv) plant functional types, (v) fire fuel load and fuel moisture content, and (vi) disturbance occurrence, type and intensity. These measurements are made using a multi-parameter, spectroscopic analysis approach afforded by observation of the full optical spectrum. Combining these measurements, along with additional observations from multispectral sensors, Flora will far advance global studies and models of ecosystem dynamics and change.
NASA Technical Reports Server (NTRS)
Green, Robert O.; Hook, Simon J.; Middleton, Elizabeth; Turner, Woody; Ungar, Stephen; Knox, Robert
2012-01-01
The NASA HyspIRI mission is planned to provide global solar reflected energy spectroscopic measurement of the terrestrial and shallow water regions of the Earth every 19 days will all measurements downlinked. In addition, HyspIRI will provide multi-spectral thermal measurements with a single band in the 4 micron region and seven bands in the 8 to 12 micron region with 5 day day/night coverage. A direct broadcast capability for measurement subsets is also planned. This HyspIRI mission is one of those designated in the 2007 National Research Council (NRC) Decadal Survey: Earth Science and Applications from Space. In the Decadal Survey, HyspIRI was recognized as relevant to a range of Earth science and science applications, including climate: "A hyperspectral sensor (e.g., FLORA) combined with a multispectral thermal sensor (e.g., SAVII) in low Earth orbit (LEO) is part of an integrated mission concept [described in Parts I and II] that is relevant to several panels, especially the climate variability panel." The HyspIRI science study group was formed in 2008 to evaluate and refine the mission concept. This group has developed a series of HyspIRI science objectives: (1) Climate: Ecosystem biochemistry, condition & feedback; spectral albedo; carbon/dust on snow/ice; biomass burning; evapotranspiration (2) Ecosystems: Global plant functional types, physiological condition, and biochemistry including agricultural lands (3) Fires: Fuel status, fire frequency, severity, emissions, and patterns of recovery globally (4) Coral reef and coastal habitats: Global composition and status (5) Volcanoes: Eruptions, emissions, regional and global impact (6) Geology and resources: Global distributions of surface mineral resources and improved understanding of geology and related hazards These objectives are achieved with the following measurement capabilities. The HyspIRI imaging spectrometer provides: full spectral coverage from 380 to 2500 at 10 nm sampling; 60 m spatial sampling with a 150 km swath; and fully downlinked coverage of the Earth's terrestrial and shallow water regions every 19 days to provide seasonal cloud-free coverage of the terrestrial surface. The HyspIRI Multi-Spectral Thermal instrument provides: 8 spectral bands from 4 to 12 microns; 60 m spatial sampling with a 600 km swath; and fully downlinked coverage of the Earth's terrestrial shallow water regions every 5 days (day/night) to provide nominally cloud-free monthly coverage. The HyspIRI mission also includes an on-board processing and direct broadcast capability, referred to as the Intelligent Payload Module (IPM), which will allow users with the appropriate antenna to download a subset of the HyspIRI data stream to a local ground station. These science and science application objectives are critical today and uniquely addressed by the combined imaging spectroscopy, thermal infrared measurements, and IPM direct broadcast capability of HyspIRI. Two key objectives are: (1) The global HyspIRI spectroscopic measurements of the terrestrial biosphere including vegetation composition and function to constrain and reduce the uncertainty in climate-carbon interactions and terrestrial biosphere feedback. (2) The global 8 band thermal measurements to provide improved constraint of fire related emissions. In this paper the current HyspIRI mission concept that has been reviewed and refined to its current level of maturity with a Data Products Symposium, Science Workshop and NASA HWorkshop is presented including traceability between the measurements and the science and science application objectives.
Cross-cultural variation of memory colors of familiar objects.
Smet, Kevin A G; Lin, Yandan; Nagy, Balázs V; Németh, Zoltan; Duque-Chica, Gloria L; Quintero, Jesús M; Chen, Hung-Shing; Luo, Ronnier M; Safi, Mahdi; Hanselaer, Peter
2014-12-29
The effect of cross-regional or cross-cultural differences on color appearance ratings and memory colors of familiar objects was investigated in seven different countries/regions - Belgium, Hungary, Brazil, Colombia, Taiwan, China and Iran. In each region the familiar objects were presented on a calibrated monitor in over 100 different colors to a test panel of observers that were asked to rate the similarity of the presented object color with respect to what they thought the object looks like in reality (memory color). For each object and region the mean observer ratings were modeled by a bivariate Gaussian function. A statistical analysis showed significant (p < 0.001) differences between the region average observers and the global average observer obtained by pooling the data from all regions. However, the effect size of geographical region or culture was found to be small. In fact, the differences between the region average observers and the global average observer were found to of the same magnitude or smaller than the typical within region inter-observer variability. Thus, although statistical differences in color appearance ratings and memory between regions were found, regional impact is not likely to be of practical importance.
Global Soil Information Facilities - Component Worldgrids.org
NASA Astrophysics Data System (ADS)
Reuter, H. I.; Hengl, T.
2012-04-01
GSIF (Global Soil Information Facilities) is ISRIC's framework for production of open soil data. It has been inspired by global environmental data initiatives (e.g. oneGeology, GBIF). The main practical motivation for GSIF is to build cyber-infrastructure to collate legacy (i.e., historic) soil data currently under threat of being lost forever and to generate new soil information. The objective of the component worldgrids is a (de)-central repository for collecting, storing, accessing and interacting with gridded data sets of global soil covariate data for production mapping, while being part of a larger GSIF. It is the physical implementation of the expectation that ISRIC would lead and coordinate a project to assemble a core data set of global environmental covariates to (partly) support local efforts to produce global soil property maps. Currently over 100 layers with a 5 and 1 km resolution with a global coverage can be accessed via www.worldgrids.org. Three different functionalities are implemented to extract data in an OGC complained matter: i) single point overlay ii) mass point overlay; iii) zone grid overlay with reporting of different statistical parameters. The presentation will focus on datasets, functionalities, access via the R-project and ArcGIS globalsoilmap.net Toolbox as well on future enhancements to the worldgrids platform.
Global optimization algorithm for heat exchanger networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quesada, I.; Grossmann, I.E.
This paper deals with the global optimization of heat exchanger networks with fixed topology. It is shown that if linear area cost functions are assumed, as well as arithmetic mean driving force temperature differences in networks with isothermal mixing, the corresponding nonlinear programming (NLP) optimization problem involves linear constraints and a sum of linear fractional functions in the objective which are nonconvex. A rigorous algorithm is proposed that is based on a convex NLP underestimator that involves linear and nonlinear estimators for fractional and bilinear terms which provide a tight lower bound to the global optimum. This NLP problem ismore » used within a spatial branch and bound method for which branching rules are given. Basic properties of the proposed method are presented, and its application is illustrated with several example problems. The results show that the proposed method only requires few nodes in the branch and bound search.« less
Stochastic HKMDHE: A multi-objective contrast enhancement algorithm
NASA Astrophysics Data System (ADS)
Pratiher, Sawon; Mukhopadhyay, Sabyasachi; Maity, Srideep; Pradhan, Asima; Ghosh, Nirmalya; Panigrahi, Prasanta K.
2018-02-01
This contribution proposes a novel extension of the existing `Hyper Kurtosis based Modified Duo-Histogram Equalization' (HKMDHE) algorithm, for multi-objective contrast enhancement of biomedical images. A novel modified objective function has been formulated by joint optimization of the individual histogram equalization objectives. The optimal adequacy of the proposed methodology with respect to image quality metrics such as brightness preserving abilities, peak signal-to-noise ratio (PSNR), Structural Similarity Index (SSIM) and universal image quality metric has been experimentally validated. The performance analysis of the proposed Stochastic HKMDHE with existing histogram equalization methodologies like Global Histogram Equalization (GHE) and Contrast Limited Adaptive Histogram Equalization (CLAHE) has been given for comparative evaluation.
Dialectical Behavior Therapy (DBT) Applied to College Students: A Randomized Clinical Trial
ERIC Educational Resources Information Center
Pistorello, Jacqueline; Fruzzetti, Alan E.; MacLane, Chelsea; Gallop, Robert; Iverson, Katherine M.
2012-01-01
Objective: College counseling centers (CCCs) are increasingly being called upon to treat highly distressed students with complex clinical presentations. This study compared the effectiveness of Dialectical Behavior Therapy (DBT) for suicidal college students with an optimized control condition and analyzed baseline global functioning as a…
USDA-ARS?s Scientific Manuscript database
Objectives: To examine the association between diet and executive function, episodic memory and global verbal cognition in the Einstein Aging Study (EAS) cohort and determine whether race modifies this relationship. Design: Cross-sectional. Setting: Community. Participants: EAS participants without ...
The objective of this study was to determine the molecular bases of disordered hepatic function and disease susceptibility in obesity. We compared global gene expression in liver biopsies from morbidly obese (MO) women undergoing gastric bypass (GBP) surgery with that of women un...
Case Study: Longitudinal Treatment of Adolescents with Depression and Inflammatory Bowel Disease
ERIC Educational Resources Information Center
Szigethy, Eva; Carpenter, Johanna; Baum, Emily; Kenney, Elyse; Baptista-Neto, Lourival; Beardslee, William R.; DeMaso, David Ray
2006-01-01
Objective: To assess longitudinal maintenance of improvements in depression, anxiety, global functioning, and physical health perception in 11 adolescents at 6 and 12 months following completion of manual-based cognitive-behavioral therapy. Method: Standardized instruments assessed follow-up changes in depression, anxiety, physical health, and…
Global Health in the Anthropocene: Moving Beyond Resilience and Capitalism
van de Pas, Remco
2017-01-01
There has been much reflection on the need for a new understanding of global health and the urgency of a paradigm shift to address global health issues. A crucial question is whether this is still possible in current modes of global governance based on capitalist values. Four reflections are provided. (1) Ecological –centered values must become central in any future global health framework. (2) The objectives of ‘sustainability’ and ‘economic growth’ present a profound contradiction. (3) The resilience discourse maintains a gridlock in the functioning of the global health system. (4) The legitimacy of multi-stakeholder governance arrangements in global health requires urgent attention. A dual track approach is suggested. It must be aimed to transform capitalism into something better for global health while in parallel there is an urgent need to imagine a future and pathways to a different world order rooted in the principles of social justice, protecting the commons and a central role for the preservation of ecology. PMID:28812849
Valencia, Marcelo; Fresán, Ana; Barak, Yoram; Juárez, Francisco; Escamilla, Raul; Saracco, Ricardo
2015-01-01
Background New approaches to assess outcome in schizophrenia include multidimensional measures such as remission, cognition, psychosocial functioning, and quality of life. Clinical and psychosocial measures have been recently introduced to assess functional outcome. Objective The study presented here was designed to examine the rates of symptomatic remission, psychosocial remission, global functioning, and clinical global impressions in a sample of schizophrenia outpatients in order to assess functional remission and to identify predictive factors for functional remission. Methods A total of 168 consecutive Mexican outpatients receiving pharmacological treatment at the National Institute of Psychiatry in Mexico City were enrolled in a cross-sectional study. Symptomatic remission was assessed according to the definition and criteria proposed by the Remission in Schizophrenia Working Group using the Positive and Negative Symptom Scale. Psychosocial remission was assessed according to Barak criteria using the Psychosocial Remission in Schizophrenia scale. Functioning was measured with the Global Assessment of Functioning, and clinical outcome with the Clinical Global Impressions (CGI) Scale. Results Findings showed that 45.2% of patients fulfilled the symptomatic remission criteria, 32.1% achieved psychosocial remission, and 53% reported adequate functioning. However, the combination of these three outcome criteria – symptomatic, psychosocial remission, and functioning – indicated that 14.9% of the patients achieved our predefined functional remission outcome. The logistic regression model included five predictive variables for functional remission: (1) being employed, (2) use of atypical antipsychotics, (3) lower number of medications, (4) lower negative symptom severity, and (5) lower excitement symptom severity. Conclusion The study demonstrated that symptomatic remission, psychosocial remission, and functioning could be achievable goals for a considerable number of patients. The outcome of functional remission was achieved by a minority of patients, less than 15%. New approaches should include multidimensional measures to assess functional outcome in schizophrenia research. PMID:26396518
Madurga-Revilla, P; López-Pisón, J; Samper-Villagrasa, P; Garcés-Gómez, R; García-Íñiguez, J P; Domínguez-Cajal, M; Gil-Hernández, I; Viscor-Zárate, S
2017-11-01
Functional health, a reliable parameter of the impact of disease, should be used systematically to assess prognosis in paediatric intensive care units (PICU). Developing scales for the assessment of functional health is therefore essential. The Paediatric Overall and Cerebral Performance Category (POPC, PCPC) scales have traditionally been used in paediatric studies. The new Functional Status Scale (FSS) was designed to provide more objective results. This study aims to confirm the validity of the FSS compared to the classic POPC and PCPC scales, and to evaluate whether it may also be superior to the latter in assessing of neurological function. We conducted a retrospective descriptive study of 266 children with neurological diseases admitted to intensive care between 2012 and 2014. Functional health at discharge and at one year after discharge was evaluated using the PCPC and POPC scales and the new FSS. Global FSS scores were found to be well correlated with all POPC scores (P<.001), except in category 5 (coma/vegetative state). Global FSS score dispersion increases with POPC category. The neurological versions of both scales show a similar correlation. Comparison with classic POPC and PCPC categories suggests that the new FSS scale is a useful method for evaluating functional health in our setting. The dispersion of FSS values underlines the poor accuracy of POPC-PCPC compared to the new FSS scale, which is more disaggregated and objective. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.
Comparison of penalty functions on a penalty approach to mixed-integer optimization
NASA Astrophysics Data System (ADS)
Francisco, Rogério B.; Costa, M. Fernanda P.; Rocha, Ana Maria A. C.; Fernandes, Edite M. G. P.
2016-06-01
In this paper, we present a comparative study involving several penalty functions that can be used in a penalty approach for globally solving bound mixed-integer nonlinear programming (bMIMLP) problems. The penalty approach relies on a continuous reformulation of the bMINLP problem by adding a particular penalty term to the objective function. A penalty function based on the `erf' function is proposed. The continuous nonlinear optimization problems are sequentially solved by the population-based firefly algorithm. Preliminary numerical experiments are carried out in order to analyze the quality of the produced solutions, when compared with other penalty functions available in the literature.
NASA Astrophysics Data System (ADS)
Chaudhuri, Anirban
Global optimization based on expensive and time consuming simulations or experiments usually cannot be carried out to convergence, but must be stopped because of time constraints, or because the cost of the additional function evaluations exceeds the benefits of improving the objective(s). This dissertation sets to explore the implications of such budget and time constraints on the balance between exploration and exploitation and the decision of when to stop. Three different aspects are considered in terms of their effects on the balance between exploration and exploitation: 1) history of optimization, 2) fixed evaluation budget, and 3) cost as a part of objective function. To this end, this research develops modifications to the surrogate-based optimization technique, Efficient Global Optimization algorithm, that controls better the balance between exploration and exploitation, and stopping criteria facilitated by these modifications. Then the focus shifts to examining experimental optimization, which shares the issues of cost and time constraints. Through a study on optimization of thrust and power for a small flapping wing for micro air vehicles, important differences and similarities between experimental and simulation-based optimization are identified. The most important difference is that reduction of noise in experiments becomes a major time and cost issue, and a second difference is that parallelism as a way to cut cost is more challenging. The experimental optimization reveals the tendency of the surrogate to display optimistic bias near the surrogate optimum, and this tendency is then verified to also occur in simulation based optimization.
Treatment effects in multiple cognitive domains in Alzheimer’s disease: a two-year cohort study
2014-01-01
Introduction Despite widespread use of second-generation cholinesterase inhibitors for the symptomatic treatment of Alzheimer’s disease (AD), little is known about the long term effects of cholinergic treatment on global cognitive function and potential specific effects in different cognitive domains. The objectives of this study were to determine the association between cholinergic treatment and global cognitive function over one and two years in a cohort of patients with mild or moderate AD and identify potential differences in domain-specific cognitive outcomes within this cohort. Methods A cohort of patients meeting the revised National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria for mild or moderate AD, including patients both on treatment with a cholinesterase inhibitor and untreated controls (treated = 65, untreated = 65), were recruited from the Cognitive Neurology Clinic at Sunnybrook Health Sciences Centre, as part of the Sunnybrook Dementia Study. Patients were followed for one to two years and underwent standardized neuropsychological assessments to evaluate global and domain-specific cognitive function. Associations between cholinesterase inhibitor use and global and domain-specific cognitive outcome measures at one and two years of follow-up were estimated using mixed model linear regression, adjusting for age, education, and baseline mini mental state examination (MMSE). Results At one year, treated patients showed significantly less decline in global cognitive function, and treatment and time effects across tests of executive and visuospatial function. At two years, there was a significant trend towards less decline in global cognition for treated patients. Moreover, treated patients showed significant treatment and time effects across tests of executive functioning, memory, and visuospatial function. Conclusions The present study offers two important contributions to knowledge of the effectiveness of cholinesterase inhibitor treatment in patients with mild-moderate AD: 1) that second-generation cholinesterase inhibitors demonstrate long-term effectiveness for reducing global cognitive decline over one to two years of follow-up, and 2) that decline in function for cognitive domains, including executive function, memory, and visuospatial skill that are primarily mediated by frontal networks and by the cholinergic system, rather than memory, may be slowed by treatment targeting the cholinergic system. PMID:25484926
NASA Astrophysics Data System (ADS)
Bonissone, Stefano R.; Subbu, Raj
2002-12-01
In multi-objective optimization (MOO) problems we need to optimize many possibly conflicting objectives. For instance, in manufacturing planning we might want to minimize the cost and production time while maximizing the product's quality. We propose the use of evolutionary algorithms (EAs) to solve these problems. Solutions are represented as individuals in a population and are assigned scores according to a fitness function that determines their relative quality. Strong solutions are selected for reproduction, and pass their genetic material to the next generation. Weak solutions are removed from the population. The fitness function evaluates each solution and returns a related score. In MOO problems, this fitness function is vector-valued, i.e. it returns a value for each objective. Therefore, instead of a global optimum, we try to find the Pareto-optimal or non-dominated frontier. We use multi-sexual EAs with as many genders as optimization criteria. We have created new crossover and gender assignment functions, and experimented with various parameters to determine the best setting (yielding the highest number of non-dominated solutions.) These experiments are conducted using a variety of fitness functions, and the algorithms are later evaluated on a flexible manufacturing problem with total cost and time minimization objectives.
Liang, X B; Wang, J
2000-01-01
This paper presents a continuous-time recurrent neural-network model for nonlinear optimization with any continuously differentiable objective function and bound constraints. Quadratic optimization with bound constraints is a special problem which can be solved by the recurrent neural network. The proposed recurrent neural network has the following characteristics. 1) It is regular in the sense that any optimum of the objective function with bound constraints is also an equilibrium point of the neural network. If the objective function to be minimized is convex, then the recurrent neural network is complete in the sense that the set of optima of the function with bound constraints coincides with the set of equilibria of the neural network. 2) The recurrent neural network is primal and quasiconvergent in the sense that its trajectory cannot escape from the feasible region and will converge to the set of equilibria of the neural network for any initial point in the feasible bound region. 3) The recurrent neural network has an attractivity property in the sense that its trajectory will eventually converge to the feasible region for any initial states even at outside of the bounded feasible region. 4) For minimizing any strictly convex quadratic objective function subject to bound constraints, the recurrent neural network is globally exponentially stable for almost any positive network parameters. Simulation results are given to demonstrate the convergence and performance of the proposed recurrent neural network for nonlinear optimization with bound constraints.
Design of vibration isolation systems using multiobjective optimization techniques
NASA Technical Reports Server (NTRS)
Rao, S. S.
1984-01-01
The design of vibration isolation systems is considered using multicriteria optimization techniques. The integrated values of the square of the force transmitted to the main mass and the square of the relative displacement between the main mass and the base are taken as the performance indices. The design of a three degrees-of-freedom isolation system with an exponentially decaying type of base disturbance is considered for illustration. Numerical results are obtained using the global criterion, utility function, bounded objective, lexicographic, goal programming, goal attainment and game theory methods. It is found that the game theory approach is superior in finding a better optimum solution with proper balance of the various objective functions.
Localized Principal Component Analysis based Curve Evolution: A Divide and Conquer Approach
Appia, Vikram; Ganapathy, Balaji; Yezzi, Anthony; Faber, Tracy
2014-01-01
We propose a novel localized principal component analysis (PCA) based curve evolution approach which evolves the segmenting curve semi-locally within various target regions (divisions) in an image and then combines these locally accurate segmentation curves to obtain a global segmentation. The training data for our approach consists of training shapes and associated auxiliary (target) masks. The masks indicate the various regions of the shape exhibiting highly correlated variations locally which may be rather independent of the variations in the distant parts of the global shape. Thus, in a sense, we are clustering the variations exhibited in the training data set. We then use a parametric model to implicitly represent each localized segmentation curve as a combination of the local shape priors obtained by representing the training shapes and the masks as a collection of signed distance functions. We also propose a parametric model to combine the locally evolved segmentation curves into a single hybrid (global) segmentation. Finally, we combine the evolution of these semilocal and global parameters to minimize an objective energy function. The resulting algorithm thus provides a globally accurate solution, which retains the local variations in shape. We present some results to illustrate how our approach performs better than the traditional approach with fully global PCA. PMID:25520901
Zahiripour, Seyed Ali; Jalali, Ali Akbar
2014-09-01
A novel switching function based on an optimization strategy for the sliding mode control (SMC) method has been provided for uncertain stochastic systems subject to actuator degradation such that the closed-loop system is globally asymptotically stable with probability one. In the previous researches the focus on sliding surface has been on proportional or proportional-integral function of states. In this research, from a degree of freedom that depends on designer choice is used to meet certain objectives. In the design of the switching function, there is a parameter which the designer can regulate for specified objectives. A sliding-mode controller is synthesized to ensure the reachability of the specified switching surface, despite actuator degradation and uncertainties. Finally, the simulation results demonstrate the effectiveness of the proposed method. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Cronan, Timothy Paul; Leger, Pierre-Majorique; Robert, Jacques; Babin, Gilbert; Charland, Patrick
2012-01-01
Enterprise Resource Planning (ERP) systems have had a significant impact on business organizations. These large systems offer opportunities for companies regarding the integration and functionality of information technology systems; in effect, companies can realize a competitive advantage that is necessary in today's global companies. However,…
Somatic Symptoms in Children and Adolescents with Anxiety Disorders
ERIC Educational Resources Information Center
Ginsburg, Golda S.; Riddle, Mark A.; Davies, Mark
2006-01-01
Objective: To evaluate the prevalence of somatic symptoms (SSs) in children and adolescents with anxiety disorders; the relationship between SSs and anxiety severity, impairment, and child global functioning; and the impact of fluvoxamine (FLV) versus pill placebo (PBO) on reducing SSs. Method: As part of a double-blind, placebo-controlled trial,…
Relationship between cardiac autonomic function and cognitive function in Alzheimer's disease.
Nonogaki, Zen; Umegaki, Hiroyuki; Makino, Taeko; Suzuki, Yusuke; Kuzuya, Masafumi
2017-01-01
Alzheimer's disease (AD) affects many central nervous structures and neurotransmitter systems. These changes affect not only cognitive function, but also cardiac autonomic function. However, the functional relationship between cardiac autonomic function and cognition in AD has not yet been investigated. The objective of the present study was to evaluate the association between cardiac autonomic function measured by heart rate variability and cognitive function in AD. A total of 78 AD patients were recruited for this study. Cardiac autonomic function was evaluated using heart rate variability analysis. Multiple linear regression analysis was used to model the association between heart rate variability and cognitive function (global cognitive function, memory, executive function and processing speed), after adjustment for covariates. Global cognitive function was negatively associated with sympathetic modulation (low-to-high frequency power ratio). Memory performance was positively associated with parasympathetic modulation (high frequency power) and negatively associated with sympathetic modulation (low-to-high frequency power ratio). These associations were independent of age, sex, educational years, diabetes, hypertension and cholinesterase inhibitor use. Cognitive function, especially in the areas of memory, is associated with cardiac autonomic function in AD. Specifically, lower cognitive performance was found to be associated with significantly higher cardiac sympathetic and lower parasympathetic function in AD. Geriatr Gerontol Int 2017; 17: 92-98. © 2015 Japan Geriatrics Society.
Stochastic Methods for Aircraft Design
NASA Technical Reports Server (NTRS)
Pelz, Richard B.; Ogot, Madara
1998-01-01
The global stochastic optimization method, simulated annealing (SA), was adapted and applied to various problems in aircraft design. The research was aimed at overcoming the problem of finding an optimal design in a space with multiple minima and roughness ubiquitous to numerically generated nonlinear objective functions. SA was modified to reduce the number of objective function evaluations for an optimal design, historically the main criticism of stochastic methods. SA was applied to many CFD/MDO problems including: low sonic-boom bodies, minimum drag on supersonic fore-bodies, minimum drag on supersonic aeroelastic fore-bodies, minimum drag on HSCT aeroelastic wings, FLOPS preliminary design code, another preliminary aircraft design study with vortex lattice aerodynamics, HSR complete aircraft aerodynamics. In every case, SA provided a simple, robust and reliable optimization method which found optimal designs in order 100 objective function evaluations. Perhaps most importantly, from this academic/industrial project, technology has been successfully transferred; this method is the method of choice for optimization problems at Northrop Grumman.
A study of perceptual analysis in a high-level autistic subject with exceptional graphic abilities.
Mottron, L; Belleville, S
1993-11-01
We report here the case study of a patient (E.C.) with an Asperger syndrome, or autism with quasinormal intelligence, who shows an outstanding ability for three-dimensional drawing of inanimate objects (savant syndrome). An assessment of the subsystems proposed in recent models of object recognition evidenced intact perceptual analysis and identification. The initial (or primal sketch), viewer-centered (or 2-1/2-D), or object-centered (3-D) representations and the recognition and name levels were functional. In contrast, E.C.'s pattern of performance in three different types of tasks converge to suggest an anomaly in the hierarchical organization of the local and global parts of a figure: a local interference effect in incongruent hierarchical visual stimuli, a deficit in relating local parts to global form information in impossible figures, and an absence of feature-grouping in graphic recall. The results are discussed in relation to normal visual perception and to current accounts of the savant syndrome in autism.
Shultz, Emily; Robinson, Kristen E.; Keim, Madelaine; Dennis, Maureen; Taylor, H. Gerry; Bigler, Erin D.; Rubin, Kenneth H.; Vannatta, Kathryn; Gerhardt, Cynthia A.; Stancin, Terry; Yeates, Keith Owen
2016-01-01
Objective Pediatric traumatic brain injury (TBI) may affect children’s ability to perform everyday tasks (i.e., adaptive functioning). Guided by the American Association for Intellectual and Developmental Disabilities (AAIDD) model, we explored the association between TBI and adaptive functioning at increasing levels of specificity (global, AAIDD domains, and subscales). We also examined the contributions of executive function and processing speed as mediators of TBI’s effects on adaptive functioning. Method Children (ages 8–13) with severe TBI (STBI; n=19), mild-moderate TBI (MTBI; n=50), or orthopedic injury (OI; n=60) completed measures of executive function (TEA-Ch) and processing speed (WISC-IV) an average of 2.7 years post-injury (SD = 1.2; range: 1–5.3). Parents rated children’s adaptive functioning (ABAS-II, BASC-2, CASP). Results STBI had lower global adaptive functioning (η2 = .04–.08) than the MTBI and OI groups, which typically did not differ. Deficits in the STBI group were particularly evident in the social domain, with specific deficits in social participation, leisure, and social adjustment (η2 = .06–.09). Jointly, executive function and processing speed were mediators of STBI’s effects on global adaptive functioning and in conceptual and social domains. In the STBI group, executive function mediated social functioning, and processing speed mediated social participation. Conclusions Children with STBI experience deficits in adaptive functioning, particularly in social adjustment, with less pronounced deficits in conceptual and practical skills. Executive function and processing speed may mediate the effects of STBI on adaptive functioning. Targeting adaptive functioning and associated cognitive deficits for intervention may enhance quality of life for pediatric TBI survivors. PMID:27182708
Walter, Kimberly N; Petry, Nancy M
2016-05-01
This cross-sectional study evaluated lifetime prevalence of suicide attempts in 170 HIV/AIDS patients with substance use disorders and the impact of suicide attempt history on subjective indices of quality of life and objective indices of cognitive and physical functioning. All patients met the diagnostic criteria for past-year cocaine or opioid use disorders and 27% of patients also had co-occurring alcohol use disorders. Compared to their counterparts without a history of a suicide attempt, patients with a history of a suicide attempt (n = 60, 35.3%) had significantly poorer emotional and cognitive quality of life scores (ps < .05), but not physical, social, or functional/global quality-of-life scores. Lifetime suicide attempt status was unrelated to objective indices of cognitive functioning, but there was a non-significant trend (p = .07) toward lower viral loads in those with a lifetime suicide attempt relative to those without. The findings indicate that suicide attempt histories are prevalent among HIV/AIDS patients with substance use disorders and relate to poorer perceived emotional and cognitive quality of life, but not objective functioning. HIV/AIDS patients with substance use disorders should be screened for lifetime histories of suicide attempts and offered assistance to improve perceived emotional and cognitive functioning. © The Author(s) 2016.
Cooperative Coevolution with Formula-Based Variable Grouping for Large-Scale Global Optimization.
Wang, Yuping; Liu, Haiyan; Wei, Fei; Zong, Tingting; Li, Xiaodong
2017-08-09
For a large-scale global optimization (LSGO) problem, divide-and-conquer is usually considered an effective strategy to decompose the problem into smaller subproblems, each of which can then be solved individually. Among these decomposition methods, variable grouping is shown to be promising in recent years. Existing variable grouping methods usually assume the problem to be black-box (i.e., assuming that an analytical model of the objective function is unknown), and they attempt to learn appropriate variable grouping that would allow for a better decomposition of the problem. In such cases, these variable grouping methods do not make a direct use of the formula of the objective function. However, it can be argued that many real-world problems are white-box problems, that is, the formulas of objective functions are often known a priori. These formulas of the objective functions provide rich information which can then be used to design an effective variable group method. In this article, a formula-based grouping strategy (FBG) for white-box problems is first proposed. It groups variables directly via the formula of an objective function which usually consists of a finite number of operations (i.e., four arithmetic operations "[Formula: see text]", "[Formula: see text]", "[Formula: see text]", "[Formula: see text]" and composite operations of basic elementary functions). In FBG, the operations are classified into two classes: one resulting in nonseparable variables, and the other resulting in separable variables. In FBG, variables can be automatically grouped into a suitable number of non-interacting subcomponents, with variables in each subcomponent being interdependent. FBG can easily be applied to any white-box problem and can be integrated into a cooperative coevolution framework. Based on FBG, a novel cooperative coevolution algorithm with formula-based variable grouping (so-called CCF) is proposed in this article for decomposing a large-scale white-box problem into several smaller subproblems and optimizing them respectively. To further enhance the efficiency of CCF, a new local search scheme is designed to improve the solution quality. To verify the efficiency of CCF, experiments are conducted on the standard LSGO benchmark suites of CEC'2008, CEC'2010, CEC'2013, and a real-world problem. Our results suggest that the performance of CCF is very competitive when compared with those of the state-of-the-art LSGO algorithms.
Case studies on optimization problems in MATLAB and COMSOL multiphysics by means of the livelink
NASA Astrophysics Data System (ADS)
Ozana, Stepan; Pies, Martin; Docekal, Tomas
2016-06-01
LiveLink for COMSOL is a tool that integrates COMSOL Multiphysics with MATLAB to extend one's modeling with scripting programming in the MATLAB environment. It allows user to utilize the full power of MATLAB and its toolboxes in preprocessing, model manipulation, and post processing. At first, the head script launches COMSOL with MATLAB and defines initial value of all parameters, refers to the objective function J described in the objective function and creates and runs the defined optimization task. Once the task is launches, the COMSOL model is being called in the iteration loop (from MATLAB environment by use of API interface), changing defined optimization parameters so that the objective function is minimized, using fmincon function to find a local or global minimum of constrained linear or nonlinear multivariable function. Once the minimum is found, it returns exit flag, terminates optimization and returns the optimized values of the parameters. The cooperation with MATLAB via LiveLink enhances a powerful computational environment with complex multiphysics simulations. The paper will introduce using of the LiveLink for COMSOL for chosen case studies in the field of technical cybernetics and bioengineering.
NASA Astrophysics Data System (ADS)
Swan, Chantal M.; Vogt, Meike; Gruber, Nicolas; Laufkoetter, Charlotte
2016-03-01
Much advancement has been made in recent years in field data assimilation, remote sensing and ecosystem modeling, yet our global view of phytoplankton biogeography beyond chlorophyll biomass is still a cursory taxonomic picture with vast areas of the open ocean requiring field validations. High performance liquid chromatography (HPLC) pigment data combined with inverse methods offer an advantage over many other phytoplankton quantification measures by way of providing an immediate perspective of the whole phytoplankton community in a sample as a function of chlorophyll biomass. Historically, such chemotaxonomic analysis has been conducted mainly at local spatial and temporal scales in the ocean. Here, we apply a widely tested inverse approach, CHEMTAX, to a global climatology of pigment observations from HPLC. This study marks the first systematic and objective global application of CHEMTAX, yielding a seasonal climatology comprised of ~1500 1°×1° global grid points of the major phytoplankton pigment types in the ocean characterizing cyanobacteria, haptophytes, chlorophytes, cryptophytes, dinoflagellates, and diatoms, with results validated against prior regional studies where possible. Key findings from this new global view of specific phytoplankton abundances from pigments are a) the large global proportion of marine haptophytes (comprising 32±5% of total chlorophyll), whose biogeochemical functional roles are relatively unknown, and b) the contrasting spatial scales of complexity in global community structure that can be explained in part by regional oceanographic conditions. The results are publically accessible via
On Improving Efficiency of Differential Evolution for Aerodynamic Shape Optimization Applications
NASA Technical Reports Server (NTRS)
Madavan, Nateri K.
2004-01-01
Differential Evolution (DE) is a simple and robust evolutionary strategy that has been proven effective in determining the global optimum for several difficult optimization problems. Although DE offers several advantages over traditional optimization approaches, its use in applications such as aerodynamic shape optimization where the objective function evaluations are computationally expensive is limited by the large number of function evaluations often required. In this paper various approaches for improving the efficiency of DE are reviewed and discussed. These approaches are implemented in a DE-based aerodynamic shape optimization method that uses a Navier-Stokes solver for the objective function evaluations. Parallelization techniques on distributed computers are used to reduce turnaround times. Results are presented for the inverse design of a turbine airfoil. The efficiency improvements achieved by the different approaches are evaluated and compared.
Competency-Based Objectives in Global Underserved Women's Health for Medical Trainees.
Chen, Chi Chiung Grace; Dougherty, Anne; Whetstone, Sara; Mama, Saifuddin T; Larkins-Pettigrew, Margaret; Raine, Susan P; Autry, Amy M
2017-10-01
The Association of Professors of Gynecology and Obstetrics Committee on Global Health developed an inclusive definition of global women's health and competency-based objectives that reflected work internationally, as well as with U.S. vulnerable and underserved populations, such as refugee and immigrant populations or those who would otherwise have compromised access to health care. The knowledge, skill, and attitude-based competencies required to fulfill each learning objective were mapped to the Accreditation Council for Graduate Medical Education Outcomes Project's educational domains and the Consortium of Universities for Global Health competency domains. The proposed global women's health definition and competency-based learning objective framework is a first step in ensuring quality standards for educating trainees to address global women's health needs. By proposing these objectives, we hope to guide future program development and spark a broader conversation that will improve health for vulnerable women and shape educational, ethical, and equitable global health experiences for medical trainees.
A Verification System for Distributed Objects with Asynchronous Method Calls
NASA Astrophysics Data System (ADS)
Ahrendt, Wolfgang; Dylla, Maximilian
We present a verification system for Creol, an object-oriented modeling language for concurrent distributed applications. The system is an instance of KeY, a framework for object-oriented software verification, which has so far been applied foremost to sequential Java. Building on KeY characteristic concepts, like dynamic logic, sequent calculus, explicit substitutions, and the taclet rule language, the system presented in this paper addresses functional correctness of Creol models featuring local cooperative thread parallelism and global communication via asynchronous method calls. The calculus heavily operates on communication histories which describe the interfaces of Creol units. Two example scenarios demonstrate the usage of the system.
Piecewise convexity of artificial neural networks.
Rister, Blaine; Rubin, Daniel L
2017-10-01
Although artificial neural networks have shown great promise in applications including computer vision and speech recognition, there remains considerable practical and theoretical difficulty in optimizing their parameters. The seemingly unreasonable success of gradient descent methods in minimizing these non-convex functions remains poorly understood. In this work we offer some theoretical guarantees for networks with piecewise affine activation functions, which have in recent years become the norm. We prove three main results. First, that the network is piecewise convex as a function of the input data. Second, that the network, considered as a function of the parameters in a single layer, all others held constant, is again piecewise convex. Third, that the network as a function of all its parameters is piecewise multi-convex, a generalization of biconvexity. From here we characterize the local minima and stationary points of the training objective, showing that they minimize the objective on certain subsets of the parameter space. We then analyze the performance of two optimization algorithms on multi-convex problems: gradient descent, and a method which repeatedly solves a number of convex sub-problems. We prove necessary convergence conditions for the first algorithm and both necessary and sufficient conditions for the second, after introducing regularization to the objective. Finally, we remark on the remaining difficulty of the global optimization problem. Under the squared error objective, we show that by varying the training data, a single rectifier neuron admits local minima arbitrarily far apart, both in objective value and parameter space. Copyright © 2017 Elsevier Ltd. All rights reserved.
Guinchard, A-C; Ghazaleh, Naghmeh; Saenz, M; Fornari, E; Prior, J O; Maeder, P; Adib, S; Maire, R
2016-11-01
We studied possible brain changes with functional MRI (fMRI) and fluorodeoxyglucose positron emission tomography (FDG-PET) in a patient with a rare, high-intensity "objective tinnitus" (high-level SOAEs) in the left ear of 10 years duration, with no associated hearing loss. This is the first case of objective cochlear tinnitus to be investigated with functional neuroimaging. The objective cochlear tinnitus was measured by Spontaneous Otoacoustic Emissions (SOAE) equipment (frequency 9689 Hz, intensity 57 dB SPL) and is clearly audible to anyone standing near the patient. Functional modifications in primary auditory areas and other brain regions were evaluated using 3T and 7T fMRI and FDG-PET. In the fMRI evaluations, a saturation of the auditory cortex at the tinnitus frequency was observed, but the global cortical tonotopic organization remained intact when compared to the results of fMRI of healthy subjects. The FDG-PET showed no evidence of an increase or decrease of activity in the auditory cortices or in the limbic system as compared to normal subjects. In this patient with high-intensity objective cochlear tinnitus, fMRI and FDG-PET showed no significant brain reorganization in auditory areas and/or in the limbic system, as reported in the literature in patients with chronic subjective tinnitus. Copyright © 2016 Elsevier B.V. All rights reserved.
Iyengar Yoga for Adolescents and Young Adults With Irritable Bowel Syndrome
Evans, Subhadra; Lung, Kirsten C.; Seidman, Laura C.; Sternlieb, Beth; Zeltzer, Lonnie K.; Tsao, Jennie C.I.
2014-01-01
Objectives Irritable bowel syndrome (IBS) is a chronic, disabling condition that greatly compromises patient functioning. The aim of this study was to assess the impact of a 6-week twice per week Iyengar yoga (IY) program on IBS symptoms in adolescents and young adults (YA) with IBS compared with a usual-care waitlist control group. Methods Assessments of symptoms, global improvement, pain, health-related quality of life, psychological distress, functional disability, fatigue, and sleep were collected pre- and posttreatment. Weekly ratings of pain, IBS symptoms, and global improvement were also recorded until 2-month follow-up. A total of 51 participants completed the intervention (yoga = 29; usual-care waitlist = 22). Results Baseline attrition was 24%. On average, the yoga group attended 75% of classes. Analyses were divided by age group. Relative to controls, adolescents (14–17 years) assigned to yoga reported significantly improved physical functioning, whereas YA (18–26 years) assigned to yoga reported significantly improved IBS symptoms, global improvement, disability, psychological distress, sleep quality, and fatigue. Although abdominal pain intensity was statistically unchanged, 44% of adolescents and 46% of YA reported a minimally clinically significant reduction in pain following yoga, and one-third of YA reported clinically significant levels of global symptom improvement. Analysis of the uncontrolled effects and maintenance of treatment effects for adolescents revealed global improvement immediately post-yoga that was not maintained at follow-up. For YA, global improvement, worst pain, constipation, and nausea were significantly improved postyoga, but only global improvement, worst pain, and nausea maintained at the 2-month follow-up. Conclusions The findings suggest that a brief IY intervention is a feasible and safe adjunctive treatment for young people with IBS, leading to benefits in a number of IBS-specific and general functioning domains for YA. The age-specific results suggest that yoga interventions may be most fruitful when developmentally tailored. PMID:25025601
2017-01-01
The role of stereo disparity in the recognition of 3-dimensional (3D) object shape remains an unresolved issue for theoretical models of the human visual system. We examined this issue using high-density (128 channel) recordings of event-related potentials (ERPs). A recognition memory task was used in which observers were trained to recognize a subset of complex, multipart, 3D novel objects under conditions of either (bi-) monocular or stereo viewing. In a subsequent test phase they discriminated previously trained targets from untrained distractor objects that shared either local parts, 3D spatial configuration, or neither dimension, across both previously seen and novel viewpoints. The behavioral data showed a stereo advantage for target recognition at untrained viewpoints. ERPs showed early differential amplitude modulations to shape similarity defined by local part structure and global 3D spatial configuration. This occurred initially during an N1 component around 145–190 ms poststimulus onset, and then subsequently during an N2/P3 component around 260–385 ms poststimulus onset. For mono viewing, amplitude modulation during the N1 was greatest between targets and distracters with different local parts for trained views only. For stereo viewing, amplitude modulation during the N2/P3 was greatest between targets and distracters with different global 3D spatial configurations and generalized across trained and untrained views. The results show that image classification is modulated by stereo information about the local part, and global 3D spatial configuration of object shape. The findings challenge current theoretical models that do not attribute functional significance to stereo input during the computation of 3D object shape. PMID:29022728
Recognition of partially occluded threat objects using the annealed Hopefield network
NASA Technical Reports Server (NTRS)
Kim, Jung H.; Yoon, Sung H.; Park, Eui H.; Ntuen, Celestine A.
1992-01-01
Recognition of partially occluded objects has been an important issue to airport security because occlusion causes significant problems in identifying and locating objects during baggage inspection. The neural network approach is suitable for the problems in the sense that the inherent parallelism of neural networks pursues many hypotheses in parallel resulting in high computation rates. Moreover, they provide a greater degree of robustness or fault tolerance than conventional computers. The annealed Hopfield network which is derived from the mean field annealing (MFA) has been developed to find global solutions of a nonlinear system. In the study, it has been proven that the system temperature of MFA is equivalent to the gain of the sigmoid function of a Hopfield network. In our early work, we developed the hybrid Hopfield network (HHN) for fast and reliable matching. However, HHN doesn't guarantee global solutions and yields false matching under heavily occluded conditions because HHN is dependent on initial states by its nature. In this paper, we present the annealed Hopfield network (AHN) for occluded object matching problems. In AHN, the mean field theory is applied to the hybird Hopfield network in order to improve computational complexity of the annealed Hopfield network and provide reliable matching under heavily occluded conditions. AHN is slower than HHN. However, AHN provides near global solutions without initial restrictions and provides less false matching than HHN. In conclusion, a new algorithm based upon a neural network approach was developed to demonstrate the feasibility of the automated inspection of threat objects from x-ray images. The robustness of the algorithm is proved by identifying occluded target objects with large tolerance of their features.
NASA Astrophysics Data System (ADS)
Abdeh-Kolahchi, A.; Satish, M.; Datta, B.
2004-05-01
A state art groundwater monitoring network design is introduced. The method combines groundwater flow and transport results with optimization Genetic Algorithm (GA) to identify optimal monitoring well locations. Optimization theory uses different techniques to find a set of parameter values that minimize or maximize objective functions. The suggested groundwater optimal monitoring network design is based on the objective of maximizing the probability of tracking a transient contamination plume by determining sequential monitoring locations. The MODFLOW and MT3DMS models included as separate modules within the Groundwater Modeling System (GMS) are used to develop three dimensional groundwater flow and contamination transport simulation. The groundwater flow and contamination simulation results are introduced as input to the optimization model, using Genetic Algorithm (GA) to identify the groundwater optimal monitoring network design, based on several candidate monitoring locations. The groundwater monitoring network design model is used Genetic Algorithms with binary variables representing potential monitoring location. As the number of decision variables and constraints increase, the non-linearity of the objective function also increases which make difficulty to obtain optimal solutions. The genetic algorithm is an evolutionary global optimization technique, which is capable of finding the optimal solution for many complex problems. In this study, the GA approach capable of finding the global optimal solution to a groundwater monitoring network design problem involving 18.4X 1018 feasible solutions will be discussed. However, to ensure the efficiency of the solution process and global optimality of the solution obtained using GA, it is necessary that appropriate GA parameter values be specified. The sensitivity analysis of genetic algorithms parameters such as random number, crossover probability, mutation probability, and elitism are discussed for solution of monitoring network design.
Algorithms for accelerated convergence of adaptive PCA.
Chatterjee, C; Kang, Z; Roychowdhury, V P
2000-01-01
We derive and discuss new adaptive algorithms for principal component analysis (PCA) that are shown to converge faster than the traditional PCA algorithms due to Oja, Sanger, and Xu. It is well known that traditional PCA algorithms that are derived by using gradient descent on an objective function are slow to converge. Furthermore, the convergence of these algorithms depends on appropriate choices of the gain sequences. Since online applications demand faster convergence and an automatic selection of gains, we present new adaptive algorithms to solve these problems. We first present an unconstrained objective function, which can be minimized to obtain the principal components. We derive adaptive algorithms from this objective function by using: 1) gradient descent; 2) steepest descent; 3) conjugate direction; and 4) Newton-Raphson methods. Although gradient descent produces Xu's LMSER algorithm, the steepest descent, conjugate direction, and Newton-Raphson methods produce new adaptive algorithms for PCA. We also provide a discussion on the landscape of the objective function, and present a global convergence proof of the adaptive gradient descent PCA algorithm using stochastic approximation theory. Extensive experiments with stationary and nonstationary multidimensional Gaussian sequences show faster convergence of the new algorithms over the traditional gradient descent methods.We also compare the steepest descent adaptive algorithm with state-of-the-art methods on stationary and nonstationary sequences.
Application of the gravity search algorithm to multi-reservoir operation optimization
NASA Astrophysics Data System (ADS)
Bozorg-Haddad, Omid; Janbaz, Mahdieh; Loáiciga, Hugo A.
2016-12-01
Complexities in river discharge, variable rainfall regime, and drought severity merit the use of advanced optimization tools in multi-reservoir operation. The gravity search algorithm (GSA) is an evolutionary optimization algorithm based on the law of gravity and mass interactions. This paper explores the GSA's efficacy for solving benchmark functions, single reservoir, and four-reservoir operation optimization problems. The GSA's solutions are compared with those of the well-known genetic algorithm (GA) in three optimization problems. The results show that the GSA's results are closer to the optimal solutions than the GA's results in minimizing the benchmark functions. The average values of the objective function equal 1.218 and 1.746 with the GSA and GA, respectively, in solving the single-reservoir hydropower operation problem. The global solution equals 1.213 for this same problem. The GSA converged to 99.97% of the global solution in its average-performing history, while the GA converged to 97% of the global solution of the four-reservoir problem. Requiring fewer parameters for algorithmic implementation and reaching the optimal solution in fewer number of functional evaluations are additional advantages of the GSA over the GA. The results of the three optimization problems demonstrate a superior performance of the GSA for optimizing general mathematical problems and the operation of reservoir systems.
Sengers, B G; Van Donkelaar, C C; Oomens, C W J; Baaijens, F P T
2004-12-01
Assessment of the functionality of tissue engineered cartilage constructs is hampered by the lack of correlation between global measurements of extra cellular matrix constituents and the global mechanical properties. Based on patterns of matrix deposition around individual cells, it has been hypothesized previously, that mechanical functionality arises when contact occurs between zones of matrix associated with individual cells. The objective of this study is to determine whether the local distribution of newly synthesized extracellular matrix components contributes to the evolution of the mechanical properties of tissue engineered cartilage constructs. A computational homogenization approach was adopted, based on the concept of a periodic representative volume element. Local transport and immobilization of newly synthesized matrix components were described. Mechanical properties were taken dependent on the local matrix concentration and subsequently the global aggregate modulus and hydraulic permeability were derived. The transport parameters were varied to assess the effect of the evolving matrix distribution during culture. The results indicate that the overall stiffness and permeability are to a large extent insensitive to differences in local matrix distribution. This emphasizes the need for caution in the visual interpretation of tissue functionality from histology and underlines the importance of complementary measurements of the matrix's intrinsic molecular organization.
Yang, Jie; Zhang, Pengcheng; Zhang, Liyuan; Shu, Huazhong; Li, Baosheng; Gui, Zhiguo
2017-01-01
In inverse treatment planning of intensity-modulated radiation therapy (IMRT), the objective function is typically the sum of the weighted sub-scores, where the weights indicate the importance of the sub-scores. To obtain a high-quality treatment plan, the planner manually adjusts the objective weights using a trial-and-error procedure until an acceptable plan is reached. In this work, a new particle swarm optimization (PSO) method which can adjust the weighting factors automatically was investigated to overcome the requirement of manual adjustment, thereby reducing the workload of the human planner and contributing to the development of a fully automated planning process. The proposed optimization method consists of three steps. (i) First, a swarm of weighting factors (i.e., particles) is initialized randomly in the search space, where each particle corresponds to a global objective function. (ii) Then, a plan optimization solver is employed to obtain the optimal solution for each particle, and the values of the evaluation functions used to determine the particle's location and the population global location for the PSO are calculated based on these results. (iii) Next, the weighting factors are updated based on the particle's location and the population global location. Step (ii) is performed alternately with step (iii) until the termination condition is reached. In this method, the evaluation function is a combination of several key points on the dose volume histograms. Furthermore, a perturbation strategy - the crossover and mutation operator hybrid approach - is employed to enhance the population diversity, and two arguments are applied to the evaluation function to improve the flexibility of the algorithm. In this study, the proposed method was used to develop IMRT treatment plans involving five unequally spaced 6MV photon beams for 10 prostate cancer cases. The proposed optimization algorithm yielded high-quality plans for all of the cases, without human planner intervention. A comparison of the results with the optimized solution obtained using a similar optimization model but with human planner intervention revealed that the proposed algorithm produced optimized plans superior to that developed using the manual plan. The proposed algorithm can generate admissible solutions within reasonable computational times and can be used to develop fully automated IMRT treatment planning methods, thus reducing human planners' workloads during iterative processes. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Research on optimal investment path of transmission corridor under the global energy Internet
NASA Astrophysics Data System (ADS)
Huang, Yuehui; Li, Pai; Wang, Qi; Liu, Jichun; Gao, Han
2018-02-01
Under the background of the global energy Internet, the investment planning of transmission corridor from XinJiang to Germany is studied in this article, which passes through four countries: Kazakhstan, Russia, Belarus and Poland. Taking the specific situation of different countries into account, including the length of transmission line, unit construction cost, completion time, transmission price, state tariff, inflation rate and so on, this paper constructed a power transmission investment model. Finally, the dynamic programming method is used to simulate the example, and the optimal strategies under different objective functions are obtained.
Motion prediction of a non-cooperative space target
NASA Astrophysics Data System (ADS)
Zhou, Bang-Zhao; Cai, Guo-Ping; Liu, Yun-Meng; Liu, Pan
2018-01-01
Capturing a non-cooperative space target is a tremendously challenging research topic. Effective acquisition of motion information of the space target is the premise to realize target capture. In this paper, motion prediction of a free-floating non-cooperative target in space is studied and a motion prediction algorithm is proposed. In order to predict the motion of the free-floating non-cooperative target, dynamic parameters of the target must be firstly identified (estimated), such as inertia, angular momentum and kinetic energy and so on; then the predicted motion of the target can be acquired by substituting these identified parameters into the Euler's equations of the target. Accurate prediction needs precise identification. This paper presents an effective method to identify these dynamic parameters of a free-floating non-cooperative target. This method is based on two steps, (1) the rough estimation of the parameters is computed using the motion observation data to the target, and (2) the best estimation of the parameters is found by an optimization method. In the optimization problem, the objective function is based on the difference between the observed and the predicted motion, and the interior-point method (IPM) is chosen as the optimization algorithm, which starts at the rough estimate obtained in the first step and finds a global minimum to the objective function with the guidance of objective function's gradient. So the speed of IPM searching for the global minimum is fast, and an accurate identification can be obtained in time. The numerical results show that the proposed motion prediction algorithm is able to predict the motion of the target.
From non-preemptive to preemptive scheduling using synchronization synthesis.
Černý, Pavol; Clarke, Edmund M; Henzinger, Thomas A; Radhakrishna, Arjun; Ryzhyk, Leonid; Samanta, Roopsha; Tarrach, Thorsten
2017-01-01
We present a computer-aided programming approach to concurrency. The approach allows programmers to program assuming a friendly, non-preemptive scheduler, and our synthesis procedure inserts synchronization to ensure that the final program works even with a preemptive scheduler. The correctness specification is implicit, inferred from the non-preemptive behavior. Let us consider sequences of calls that the program makes to an external interface. The specification requires that any such sequence produced under a preemptive scheduler should be included in the set of sequences produced under a non-preemptive scheduler. We guarantee that our synthesis does not introduce deadlocks and that the synchronization inserted is optimal w.r.t. a given objective function. The solution is based on a finitary abstraction, an algorithm for bounded language inclusion modulo an independence relation, and generation of a set of global constraints over synchronization placements. Each model of the global constraints set corresponds to a correctness-ensuring synchronization placement. The placement that is optimal w.r.t. the given objective function is chosen as the synchronization solution. We apply the approach to device-driver programming, where the driver threads call the software interface of the device and the API provided by the operating system. Our experiments demonstrate that our synthesis method is precise and efficient. The implicit specification helped us find one concurrency bug previously missed when model-checking using an explicit, user-provided specification. We implemented objective functions for coarse-grained and fine-grained locking and observed that different synchronization placements are produced for our experiments, favoring a minimal number of synchronization operations or maximum concurrency, respectively.
Deniz, Cem M; Vaidya, Manushka V; Sodickson, Daniel K; Lattanzi, Riccardo
2016-01-01
We investigated global specific absorption rate (SAR) and radiofrequency (RF) power requirements in parallel transmission as the distance between the transmit coils and the sample was increased. We calculated ultimate intrinsic SAR (UISAR), which depends on object geometry and electrical properties but not on coil design, and we used it as the reference to compare the performance of various transmit arrays. We investigated the case of fixing coil size and increasing the number of coils while moving the array away from the sample, as well as the case of fixing coil number and scaling coil dimensions. We also investigated RF power requirements as a function of lift-off, and tracked local SAR distributions associated with global SAR optima. In all cases, the target excitation profile was achieved and global SAR (as well as associated maximum local SAR) decreased with lift-off, approaching UISAR, which was constant for all lift-offs. We observed a lift-off value that optimizes the balance between global SAR and power losses in coil conductors. We showed that, using parallel transmission, global SAR can decrease at ultra high fields for finite arrays with a sufficient number of transmit elements. For parallel transmission, the distance between coils and object can be optimized to reduce SAR and minimize RF power requirements associated with homogeneous excitation. © 2015 Wiley Periodicals, Inc.
Ip, Ifan Betina; Bridge, Holly; Parker, Andrew J.
2014-01-01
An important advance in the study of visual attention has been the identification of a non-spatial component of attention that enhances the response to similar features or objects across the visual field. Here we test whether this non-spatial component can co-select individual features that are perceptually bound into a coherent object. We combined human psychophysics and functional magnetic resonance imaging (fMRI) to demonstrate the ability to co-select individual features from perceptually coherent objects. Our study used binocular disparity and visual motion to define disparity structure-from-motion (dSFM) stimuli. Although the spatial attention system induced strong modulations of the fMRI response in visual regions, the non-spatial system’s ability to co-select features of the dSFM stimulus was less pronounced and variable across subjects. Our results demonstrate that feature and global feature attention effects are variable across participants, suggesting that the feature attention system may be limited in its ability to automatically select features within the attended object. Careful comparison of the task design suggests that even minor differences in the perceptual task may be critical in revealing the presence of global feature attention. PMID:24936974
Apparent rotation properties of space debris extracted from photometric measurements
NASA Astrophysics Data System (ADS)
Šilha, Jiří; Pittet, Jean-Noël; Hamara, Michal; Schildknecht, Thomas
2018-02-01
Knowledge about the rotation properties of space debris objects is essential for the active debris removal missions, accurate re-entry predictions and to investigate the long-term effects of the space environment on the attitude motion change. Different orbital regions and object's physical properties lead to different attitude states and their change over time. Since 2007 the Astronomical Institute of the University of Bern (AIUB) performs photometric measurements of space debris objects. To June 2016 almost 2000 light curves of more than 400 individual objects have been acquired and processed. These objects are situated in all orbital regions, from low Earth orbit (LEO), via global navigation systems orbits and high eccentricity orbit (HEO), to geosynchronous Earth orbit (GEO). All types of objects were observed including the non-functional spacecraft, rocket bodies, fragmentation debris and uncorrelated objects discovered during dedicated surveys. For data acquisition, we used the 1-meter Zimmerwald Laser and Astrometry Telescope (ZIMLAT) at the Swiss Optical Ground Station and Geodynamics Observatory Zimmerwald, Switzerland. We applied our own method of phase-diagram reconstruction to extract the apparent rotation period from the light curve. Presented is the AIUB's light curve database and the obtained rotation properties of space debris as a function of object type and orbit.
Calderone, Daniel J.; Hoptman, Matthew J.; Martínez, Antígona; Nair-Collins, Sangeeta; Mauro, Cristina J.; Bar, Moshe; Javitt, Daniel C.; Butler, Pamela D.
2013-01-01
Patients with schizophrenia exhibit cognitive and sensory impairment, and object recognition deficits have been linked to sensory deficits. The “frame and fill” model of object recognition posits that low spatial frequency (LSF) information rapidly reaches the prefrontal cortex (PFC) and creates a general shape of an object that feeds back to the ventral temporal cortex to assist object recognition. Visual dysfunction findings in schizophrenia suggest a preferential loss of LSF information. This study used functional magnetic resonance imaging (fMRI) and resting state functional connectivity (RSFC) to investigate the contribution of visual deficits to impaired object “framing” circuitry in schizophrenia. Participants were shown object stimuli that were intact or contained only LSF or high spatial frequency (HSF) information. For controls, fMRI revealed preferential activation to LSF information in precuneus, superior temporal, and medial and dorsolateral PFC areas, whereas patients showed a preference for HSF information or no preference. RSFC revealed a lack of connectivity between early visual areas and PFC for patients. These results demonstrate impaired processing of LSF information during object recognition in schizophrenia, with patients instead displaying increased processing of HSF information. This is consistent with findings of a preference for local over global visual information in schizophrenia. PMID:22735157
On Improving Efficiency of Differential Evolution for Aerodynamic Shape Optimization Applications
NASA Technical Reports Server (NTRS)
Madavan, Nateri K.
2004-01-01
Differential Evolution (DE) is a simple and robust evolutionary strategy that has been provEn effective in determining the global optimum for several difficult optimization problems. Although DE offers several advantages over traditional optimization approaches, its use in applications such as aerodynamic shape optimization where the objective function evaluations are computationally expensive is limited by the large number of function evaluations often required. In this paper various approaches for improving the efficiency of DE are reviewed and discussed. Several approaches that have proven effective for other evolutionary algorithms are modified and implemented in a DE-based aerodynamic shape optimization method that uses a Navier-Stokes solver for the objective function evaluations. Parallelization techniques on distributed computers are used to reduce turnaround times. Results are presented for standard test optimization problems and for the inverse design of a turbine airfoil. The efficiency improvements achieved by the different approaches are evaluated and compared.
Ravindran, Sindhu; Jambek, Asral Bahari; Muthusamy, Hariharan; Neoh, Siew-Chin
2015-01-01
A novel clinical decision support system is proposed in this paper for evaluating the fetal well-being from the cardiotocogram (CTG) dataset through an Improved Adaptive Genetic Algorithm (IAGA) and Extreme Learning Machine (ELM). IAGA employs a new scaling technique (called sigma scaling) to avoid premature convergence and applies adaptive crossover and mutation techniques with masking concepts to enhance population diversity. Also, this search algorithm utilizes three different fitness functions (two single objective fitness functions and multi-objective fitness function) to assess its performance. The classification results unfold that promising classification accuracy of 94% is obtained with an optimal feature subset using IAGA. Also, the classification results are compared with those of other Feature Reduction techniques to substantiate its exhaustive search towards the global optimum. Besides, five other benchmark datasets are used to gauge the strength of the proposed IAGA algorithm.
Optimal Resource Allocation for NOMA-TDMA Scheme with α-Fairness in Industrial Internet of Things.
Sun, Yanjing; Guo, Yiyu; Li, Song; Wu, Dapeng; Wang, Bin
2018-05-15
In this paper, a joint non-orthogonal multiple access and time division multiple access (NOMA-TDMA) scheme is proposed in Industrial Internet of Things (IIoT), which allowed multiple sensors to transmit in the same time-frequency resource block using NOMA. The user scheduling, time slot allocation, and power control are jointly optimized in order to maximize the system α -fair utility under transmit power constraint and minimum rate constraint. The optimization problem is nonconvex because of the fractional objective function and the nonconvex constraints. To deal with the original problem, we firstly convert the objective function in the optimization problem into a difference of two convex functions (D.C.) form, and then propose a NOMA-TDMA-DC algorithm to exploit the global optimum. Numerical results show that the NOMA-TDMA scheme significantly outperforms the traditional orthogonal multiple access scheme in terms of both spectral efficiency and user fairness.
ERIC Educational Resources Information Center
Nkansah-Amankra, Stephen; Walker, Ashley Dawn
2012-01-01
Objective: Self-rated health (SRH) has become a key organizing construct for assessing multiple dimensions of populations' physical and psychosocial health functioning. However, it is unclear how adolescents' subjective self assessment of health reflects health risk exposures, co-occurring health risks (problem behaviours) and other pre-existing…
Quadratic Optimisation with One Quadratic Equality Constraint
2010-06-01
This report presents a theoretical framework for minimising a quadratic objective function subject to a quadratic equality constraint. The first part of the report gives a detailed algorithm which computes the global minimiser without calling special nonlinear optimisation solvers. The second part of the report shows how the developed theory can be applied to solve the time of arrival geolocation problem.
Utility of coupling nonlinear optimization methods with numerical modeling software
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murphy, M.J.
1996-08-05
Results of using GLO (Global Local Optimizer), a general purpose nonlinear optimization software package for investigating multi-parameter problems in science and engineering is discussed. The package consists of the modular optimization control system (GLO), a graphical user interface (GLO-GUI), a pre-processor (GLO-PUT), a post-processor (GLO-GET), and nonlinear optimization software modules, GLOBAL & LOCAL. GLO is designed for controlling and easy coupling to any scientific software application. GLO runs the optimization module and scientific software application in an iterative loop. At each iteration, the optimization module defines new values for the set of parameters being optimized. GLO-PUT inserts the new parametermore » values into the input file of the scientific application. GLO runs the application with the new parameter values. GLO-GET determines the value of the objective function by extracting the results of the analysis and comparing to the desired result. GLO continues to run the scientific application over and over until it finds the ``best`` set of parameters by minimizing (or maximizing) the objective function. An example problem showing the optimization of material model is presented (Taylor cylinder impact test).« less
Spiral bacterial foraging optimization method: Algorithm, evaluation and convergence analysis
NASA Astrophysics Data System (ADS)
Kasaiezadeh, Alireza; Khajepour, Amir; Waslander, Steven L.
2014-04-01
A biologically-inspired algorithm called Spiral Bacterial Foraging Optimization (SBFO) is investigated in this article. SBFO, previously proposed by the same authors, is a multi-agent, gradient-based algorithm that minimizes both the main objective function (local cost) and the distance between each agent and a temporary central point (global cost). A random jump is included normal to the connecting line of each agent to the central point, which produces a vortex around the temporary central point. This random jump is also suitable to cope with premature convergence, which is a feature of swarm-based optimization methods. The most important advantages of this algorithm are as follows: First, this algorithm involves a stochastic type of search with a deterministic convergence. Second, as gradient-based methods are employed, faster convergence is demonstrated over GA, DE, BFO, etc. Third, the algorithm can be implemented in a parallel fashion in order to decentralize large-scale computation. Fourth, the algorithm has a limited number of tunable parameters, and finally SBFO has a strong certainty of convergence which is rare in existing global optimization algorithms. A detailed convergence analysis of SBFO for continuously differentiable objective functions has also been investigated in this article.
Soldan, Anja; Mangels, Jennifer A; Cooper, Lynn A
2006-03-01
This study was designed to differentiate between structural description and bias accounts of performance in the possible/impossible object-decision test. Two event-related potential (ERP) studies examined how the visual system processes structurally possible and impossible objects. Specifically, the authors investigated the effects of object repetition on a series of early posterior components during structural (Experiment 1) and functional (Experiment 2) encoding and the relationship of these effects to behavioral measures of priming. In both experiments, the authors found repetition enhancement of the posterior N1 and N2 for possible objects only. In addition, the magnitude of the N1 repetition effect for possible objects was correlated with priming for possible objects. Although the behavioral results were more ambiguous, these ERP results fail to support bias models that hold that both possible and impossible objects are processed similarly in the visual system. Instead, they support the view that priming is supported by a structural description system that encodes the global 3-dimensional structure of an object.
Menning, Lisa; Garg, Gaurav; Pokharel, Deepa; Thrush, Elizabeth; Farrell, Margaret; Kodio, Frederic Kunjbe; Veira, Chantal Laroche; Wanyoike, Sarah; Malik, Suleman; Patel, Manish; Rosenbauer, Oliver
2017-07-01
The requirements under objective 2 of the Polio Eradication and Endgame Strategic Plan 2013-2018-to introduce at least 1 dose of inactivated poliomyelitis vaccine (IPV); withdraw oral poliomyelitis vaccine (OPV), starting with the type 2 component; and strengthen routine immunization programs-set an ambitious series of targets for countries. Effective implementation of IPV introduction and the switch from trivalent OPV (containing types 1, 2, and 3 poliovirus) to bivalent OPV (containing types 1 and 3 poliovirus) called for intense global communications and coordination on an unprecedented scale from 2014 to 2016, involving global public health technical agencies and donors, vaccine manufacturers, World Health Organization and United Nations Children's Fund regional offices, and national governments. At the outset, the new program requirements were perceived as challenging to communicate, difficult to understand, unrealistic in terms of timelines, and potentially infeasible for logistical implementation. In this context, a number of core areas of work for communications were established: (1) generating awareness and political commitment via global communications and advocacy; (2) informing national decision-making, planning, and implementation; and (3) in-country program communications and capacity building, to ensure acceptance of IPV and continued uptake of OPV. Central to the communications function in driving progress for objective 2 was its ability to generate a meaningful policy dialogue about polio vaccines and routine immunization at multiple levels. This included efforts to facilitate stakeholder engagement and ownership, strengthen coordination at all levels, and ensure an iterative process of feedback and learning. This article provides an overview of the global efforts and challenges in successfully implementing the communications activities to support objective 2. Lessons from the achievements by countries and partners will likely be drawn upon when all OPVs are completely withdrawn after polio eradication, but also may offer a useful model for other global health initiatives. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
NASA Astrophysics Data System (ADS)
Raygan, R.
Global collaboration in support of an International Information System (IIS) for Orbital Space Data (OSD) literally requires a global enterprise. As with many information technology enterprise initiatives attempting to coral the desires of business with the budgets and limitations of technology, Space Situational Awareness (SSA) includes many of the same challenges: 1) Adaptive / Intuitive Dash Board that facilitates User Experience Design for a variety of users. 2) Asset Management of hundreds of thousands of objects moving at thousands of miles per hour hundreds of miles in space. 3) Normalization and integration of diverse data in various languages, possibly hidden or protected from easy access. 4) Expectations of near real-time information availability coupled with predictive analysis to affect decisions before critical points of no return, such as Space Object Conjunction Assessment (CA). 5) Data Ownership, management, taxonomy, and accuracy. 6) Integrated metrics and easily modified algorithms for "what if" analysis. This paper proposes an approach to define the functional capabilities for an IIS for OSD. These functional capabilities not only address previously identified gaps in current systems but incorporate lessons learned from other big data, enterprise, and agile information technology initiatives that correlate to the space domain. Viewing the IIS as the "data service provider" allows adoption of existing information technology processes which strengthen governance and ensure service consumers certain levels of service dependability and accuracy.
Pires Marques, Tiago
2017-09-01
In the last few decades, the definition of deontological ethics, a well-identified ethical territory in psychiatry, has been the object of increasing concerns. This has been the case in France, where claims of a specific ethical tradition in psychiatry have accompanied the institutionalization of psychiatric ethics and the perceived globalization of an Anglo-American model of mental health care. This study traces the history of the 'French ethical tradition in psychiatry' and its relationship with establishing institutional spaces for ethical decision-making. The 'ethical tradition' thus conceived proves to be functional in terms of preserving the threatened identity of French psychiatry. Nevertheless, this movement also pinpoints impasses that transcend the French context and may provide valuable resources for ethical reflections on mental health on a global scale.
Gender differences in delusional disorder: Evidence from an outpatient sample.
de Portugal, Enrique; González, Nieves; Miriam, Vilaplana; Haro, Josep M; Usall, Judit; Cervilla, Jorge A
2010-05-15
Our objective was to study gender differences in delusional disorder (DD), by comparing potential risk factors, clinical correlates, illness course characteristics, and functionality. The sample was composed of 86 outpatients with DD (according to the SCID-I for DSM-IV criteria). The following assessment instruments were used service use and demographic questionnaires, Standardized Assessment of Personality (SAP), the Positive and Negative Symptom Scale (PANSS), Montgomery-Asberg Depression Rating Scale (MADRS), Mini-Mental State Examination (MMSE), Mini International Neuropsychiatry Interview (MINI), Sheehan Disability Inventory (SDI), and the Global Assessment of Functioning (GAF) scale. The female-to-male ratio was 1.6:1. Men were more likely to be single, while women were more likely to be widows. Men had a greater frequency of schizoid and schizotypal premorbid personality disorders and of premorbid substance abuse. There were no differences for other risk factors (immigration, deafness, late onset, other personality disorders, and family history). Men were younger at onset and more frequently had acute onset of the disorder. Men had more severe symptoms (higher score on the global or separate PANSS scales). There were no gender differences for the remaining symptomatological variables (types of DD, presence and severity of depression, presence of hallucinations, severity of global cognitive functioning and presence of axis I comorbidity). Global and partial (work, family, and social) functioning was significantly poorer among men. Course type and consumption of resources appeared to be similar. We conclude that men with DD had significantly more severe symptoms and worse functionality. They also had a higher frequency of schizoid and schizotypal premorbid personality disorders and premorbid substance abuse. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.
Karim, Roksana; Dang, Ha; Henderson, Victor W.; Hodis, Howard N.; St John, Jan; Brinton, Roberta D.; Mack, Wendy J.
2016-01-01
Background/objectives Given the potent role of sex hormones on brain chemistry and function, we investigated the association of reproductive history indicators of hormonal exposures, including reproductive period, pregnancy, and use of hormonal contraceptives, on mid- and late-life cognition in postmenopausal women. Design Analysis of baseline data from two randomized clinical trials, the Women’s Isoflavone Soy Health (WISH) and the Early vs Late Intervention Trial of Estradiol (ELITE). Setting University academic research center Participants 830 naturally menopausal women Measurements Participants were uniformly evaluated with a cognitive battery and a structured reproductive history. Outcomes were composite scores for verbal episodic memory, executive functions, and global cognition. Reproductive variables included ages at pregnancies, menarche, and menopause, reproductive period, number of pregnancies, and use of hormones for contraception and menopausal symptoms. Multivariable linear regression evaluated associations between cognitive scores (dependent variable) and reproductive factors (independent variables), adjusting for age, race/ethnicity, income and education. Results On multivariable modeling, age at menarche ≥ 13 years of age was inversely associated with global cognition (p= 0.05). Last pregnancy after age 35 was positively associated with verbal memory (p=0.03). Use of hormonal contraceptives was positively associated with global cognition (p trend=0.04), and verbal memory (p trend=0.007). The association between hormonal contraceptive use and verbal memory and executive functions was strongest for more than 10 years of use. Reproductive period was positively associated with global cognition (p=0.04) and executive functions (p=0.04). Conclusion In this sample of healthy postmenopausal women, reproductive life events related to sex hormones, including earlier age at menarche, later age at last pregnancy, length of reproductive period, and use of oral contraceptives are positively related to aspects of cognition in later life. PMID:27996108
Visual laterality in dolphins: importance of the familiarity of stimuli
2012-01-01
Background Many studies of cerebral asymmetries in different species lead, on the one hand, to a better understanding of the functions of each cerebral hemisphere and, on the other hand, to develop an evolutionary history of hemispheric laterality. Our animal model is particularly interesting because of its original evolutionary path, i.e. return to aquatic life after a terrestrial phase. The rare reports concerning visual laterality of marine mammals investigated mainly discrimination processes. As dolphins are migrant species they are confronted to a changing environment. Being able to categorize new versus familiar objects would allow dolphins a rapid adaptation to novel environments. Visual laterality could be a prerequisite to this adaptability. To date, no study, to our knowledge, has analyzed the environmental factors that could influence their visual laterality. Results We investigated visual laterality expressed spontaneously at the water surface by a group of five common bottlenose dolphins (Tursiops truncatus) in response to various stimuli. The stimuli presented ranged from very familiar objects (known and manipulated previously) to familiar objects (known but never manipulated) to unfamiliar objects (unknown, never seen previously). At the group level, dolphins used their left eye to observe very familiar objects and their right eye to observe unfamiliar objects. However, eyes are used indifferently to observe familiar objects with intermediate valence. Conclusion Our results suggest different visual cerebral processes based either on the global shape of well-known objects or on local details of unknown objects. Moreover, the manipulation of an object appears necessary for these dolphins to construct a global representation of an object enabling its immediate categorization for subsequent use. Our experimental results pointed out some cognitive capacities of dolphins which might be crucial for their wild life given their fission-fusion social system and migratory behaviour. PMID:22239860
Visual laterality in dolphins: importance of the familiarity of stimuli.
Blois-Heulin, Catherine; Crével, Mélodie; Böye, Martin; Lemasson, Alban
2012-01-12
Many studies of cerebral asymmetries in different species lead, on the one hand, to a better understanding of the functions of each cerebral hemisphere and, on the other hand, to develop an evolutionary history of hemispheric laterality. Our animal model is particularly interesting because of its original evolutionary path, i.e. return to aquatic life after a terrestrial phase. The rare reports concerning visual laterality of marine mammals investigated mainly discrimination processes. As dolphins are migrant species they are confronted to a changing environment. Being able to categorize new versus familiar objects would allow dolphins a rapid adaptation to novel environments. Visual laterality could be a prerequisite to this adaptability. To date, no study, to our knowledge, has analyzed the environmental factors that could influence their visual laterality. We investigated visual laterality expressed spontaneously at the water surface by a group of five common bottlenose dolphins (Tursiops truncatus) in response to various stimuli. The stimuli presented ranged from very familiar objects (known and manipulated previously) to familiar objects (known but never manipulated) to unfamiliar objects (unknown, never seen previously). At the group level, dolphins used their left eye to observe very familiar objects and their right eye to observe unfamiliar objects. However, eyes are used indifferently to observe familiar objects with intermediate valence. Our results suggest different visual cerebral processes based either on the global shape of well-known objects or on local details of unknown objects. Moreover, the manipulation of an object appears necessary for these dolphins to construct a global representation of an object enabling its immediate categorization for subsequent use. Our experimental results pointed out some cognitive capacities of dolphins which might be crucial for their wild life given their fission-fusion social system and migratory behaviour.
Low Temperature Performance of High-Speed Neural Network Circuits
NASA Technical Reports Server (NTRS)
Duong, T.; Tran, M.; Daud, T.; Thakoor, A.
1995-01-01
Artificial neural networks, derived from their biological counterparts, offer a new and enabling computing paradigm specially suitable for such tasks as image and signal processing with feature classification/object recognition, global optimization, and adaptive control. When implemented in fully parallel electronic hardware, it offers orders of magnitude speed advantage. Basic building blocks of the new architecture are the processing elements called neurons implemented as nonlinear operational amplifiers with sigmoidal transfer function, interconnected through weighted connections called synapses implemented using circuitry for weight storage and multiply functions either in an analog, digital, or hybrid scheme.
Global ensemble texture representations are critical to rapid scene perception.
Brady, Timothy F; Shafer-Skelton, Anna; Alvarez, George A
2017-06-01
Traditionally, recognizing the objects within a scene has been treated as a prerequisite to recognizing the scene itself. However, research now suggests that the ability to rapidly recognize visual scenes could be supported by global properties of the scene itself rather than the objects within the scene. Here, we argue for a particular instantiation of this view: That scenes are recognized by treating them as a global texture and processing the pattern of orientations and spatial frequencies across different areas of the scene without recognizing any objects. To test this model, we asked whether there is a link between how proficient individuals are at rapid scene perception and how proficiently they represent simple spatial patterns of orientation information (global ensemble texture). We find a significant and selective correlation between these tasks, suggesting a link between scene perception and spatial ensemble tasks but not nonspatial summary statistics In a second and third experiment, we additionally show that global ensemble texture information is not only associated with scene recognition, but that preserving only global ensemble texture information from scenes is sufficient to support rapid scene perception; however, preserving the same information is not sufficient for object recognition. Thus, global ensemble texture alone is sufficient to allow activation of scene representations but not object representations. Together, these results provide evidence for a view of scene recognition based on global ensemble texture rather than a view based purely on objects or on nonspatially localized global properties. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Richard-Denis, Andréane; Beauséjour, Marie; Thompson, Cynthia; Nguyen, Bich-Han; Mac-Thiong, Jean-Marc
2018-04-17
Accurately predicting functional recovery is an asset for all clinicians and decision makers involved in the care of patients with acute traumatic spinal cord injury (TSCI). Unfortunately, there is a lack of information on the relative importance of significant predictors of global functional outcome. There is also a need for identifying functional predictors that can be timely optimized by the medical and rehabilitation teams throughout the hospitalizations phases. The main objective of this work was to systematically review and rate early factors that are consistently and independently associated with global functional outcome in individuals with TSCI. A literature search using MEDLINE, EMBASE, and Cochrane databases from January 1, 1970 to April 1, 2017 was performed. Two authors independently reviewed the titles and abstracts yielded by this literature search and subsequently selected studies to be included based on predetermined eligibility criteria. Disagreements were resolved by a consensus-based discussion, and if not, by an external reviewer. Data were extracted by three independent reviewers using a standardized table. The quality of evidence of the individual studies was assessed based on the Oxford Center for Evidence-Based Medicine modified by Wright and colleagues (2000) as well as the National Institutes of Health (2014). Fifteen articles identifying early clinical predictors of functional outcome using multiple regression analyses were included in this systematic review. Based on the compiled data, this review proposes a rating of early factors associated to global functional outcome according to their importance and their potential to be modified by the medical/rehabilitation team throughout the early phases of hospitalization. It also proposes a new conceptual framework that illustrates the impact of specific categories of factors and their interaction with each other. Ultimately, this review aims to guide clinicians and researchers in improving the continuum of care throughout early phases post-SCI.
Takemoto, Michelle; Carlson, Jordan A; Moran, Kevin; Godbole, Suneeta; Crist, Katie; Kerr, Jacqueline
2015-10-30
This study used objective Global Positioning Systems (GPS) to investigate the relationship between pedestrian and vehicle trips to physical, cognitive, and psychological functioning in older adults living in retirement communities. Older adults (N = 279; mean age = 83 ± 6 years) wore a GPS and accelerometer for 6 days. Participants completed standard health measures. The Personal Activity and Location Measurement System (PALMS) was used to calculate the average daily number of trips, distance, and minutes traveled for pedestrian and vehicle trips from the combined GPS and accelerometer data. Linear mixed effects regression models explored relationships between these transportation variables and physical, psychological and cognitive functioning. Number, distance, and minutes of pedestrian trips were positively associated with physical and psychological functioning but not cognitive functioning. Number of vehicle trips was negatively associated with fear of falls; there were no other associations between the vehicle trip variables and functioning. Vehicle travel did not appear to be related to functioning in older adults in retirement communities except that fear of falling was related to number of vehicle trips. Pedestrian trips had moderate associations with multiple physical and psychological functioning measures, supporting a link between walking and many aspects of health in older adults.
Thompson, Deanne K.; Chen, Jian; Beare, Richard; Adamson, Christopher L.; Ellis, Rachel; Ahmadzai, Zohra M.; Kelly, Claire E.; Lee, Katherine J.; Zalesky, Andrew; Yang, Joseph Y.M.; Hunt, Rodney W.; Cheong, Jeanie L.Y.; Inder, Terrie E.; Doyle, Lex W.; Seal, Marc L.; Anderson, Peter J.
2016-01-01
Objective To use structural connectivity to (1) compare brain networks between typically and atypically developing (very preterm) children, (2) explore associations between potential perinatal developmental disturbances and brain networks, and (3) describe associations between brain networks and functional impairments in very preterm children. Methods 26 full-term and 107 very preterm 7-year-old children (born <30 weeks’ gestational age and/or <1250 g) underwent T1- and diffusion-weighted imaging. Global white matter fiber networks were produced using 80 cortical and subcortical nodes, and edges created using constrained spherical deconvolution-based tractography. Global graph theory metrics were analysed, and regional networks were identified using network-based statistics. Cognitive and motor function were assessed at 7 years of age. Results Compared with full-term children, very preterm children had reduced density, lower global efficiency and higher local efficiency. Those with lower gestational age at birth, infection or higher neonatal brain abnormality score had reduced connectivity. Reduced connectivity within a widespread network was predictive of impaired IQ, while reduced connectivity within the right parietal and temporal lobes was associated with motor impairment in very preterm children. Conclusions This study utilized an innovative structural connectivity pipeline to reveal that children born very preterm have less connected and less complex brain networks compared with typically developing term-born children. Adverse perinatal factors led to disturbances in white matter connectivity, which in turn are associated with impaired functional outcomes, highlighting novel structure-function relationships. PMID:27046108
Gerlach, Christian; Starrfelt, Randi
2018-03-20
There has been an increase in studies adopting an individual difference approach to examine visual cognition and in particular in studies trying to relate face recognition performance with measures of holistic processing (the face composite effect and the part-whole effect). In the present study we examine whether global precedence effects, measured by means of non-face stimuli in Navon's paradigm, can also account for individual differences in face recognition and, if so, whether the effect is of similar magnitude for faces and objects. We find evidence that global precedence effects facilitate both face and object recognition, and to a similar extent. Our results suggest that both face and object recognition are characterized by a coarse-to-fine temporal dynamic, where global shape information is derived prior to local shape information, and that the efficiency of face and object recognition is related to the magnitude of the global precedence effect.
Nawrocka, Agnieszka; Mynarski, Władysław; Cholewa, Jarosław
2017-12-23
Physical activity is an important factor in maintaining the health and functional fitness of elderly people. The aim of the study was to determine the number of senior women meeting the physical activity guidelines, and their level of functional fitness in comparison to women who are not sufficiently physically active. The study involved 61 women, aged 60-75. Physical activity was monitored on seven consecutive days of the week, using a triaxial accelerometer ActiGraph GT3X. Results of the assessment of physical activity were verified against the Global Recommendations of Physical Activity for Health. The Senior Fitness Test (Fullerton Test) was used to evaluate functional fitness. In the studied group, 36.1% achieved the recommended level of physical activity. All those examined mainly undertook physical activity of low intensity. Vigorous physical activity during the week was noted in only 6 seniors. Women who met the recommendations of physical activity achieved significantly better results in test trials, e.g. Chair Stands, Up and Go, Six Minute Step Test. Adherence to physical activity guidelines was associated with better functional fitness of older women. However, less than half of the examined seniors met the Global Recommendations on Physical Activity for Health.
Reduced integration and improved segregation of functional brain networks in Alzheimer's disease.
Kabbara, A; Eid, H; El Falou, W; Khalil, M; Wendling, F; Hassan, M
2018-04-01
Emerging evidence shows that cognitive deficits in Alzheimer's disease (AD) are associated with disruptions in brain functional connectivity. Thus, the identification of alterations in AD functional networks has become a topic of increasing interest. However, to what extent AD induces disruption of the balance of local and global information processing in the human brain remains elusive. The main objective of this study is to explore the dynamic topological changes of AD networks in terms of brain network segregation and integration. We used electroencephalography (EEG) data recorded from 20 participants (10 AD patients and 10 healthy controls) during resting state. Functional brain networks were reconstructed using EEG source connectivity computed in different frequency bands. Graph theoretical analyses were performed assess differences between both groups. Results revealed that AD networks, compared to networks of age-matched healthy controls, are characterized by lower global information processing (integration) and higher local information processing (segregation). Results showed also significant correlation between the alterations in the AD patients' functional brain networks and their cognitive scores. These findings may contribute to the development of EEG network-based test that could strengthen results obtained from currently-used neurophysiological tests in neurodegenerative diseases.
Fiebelkorn, Ian C; Foxe, John J; McCourt, Mark E; Dumas, Kristina N; Molholm, Sophie
2013-05-01
Behavioral evidence for an impaired ability to group objects based on similar physical or semantic properties in autism spectrum disorders (ASD) has been mixed. Here, we recorded brain activity from high-functioning children with ASD as they completed a visual-target detection task. We then assessed the extent to which object-based selective attention automatically generalized from targets to non-target exemplars from the same well-known object class (e.g., dogs). Our results provide clear electrophysiological evidence that children with ASD (N=17, aged 8-13 years) process the similarity between targets (e.g., a specific dog) and same-category non-targets (SCNT) (e.g., another dog) to a lesser extent than do their typically developing (TD) peers (N=21). A closer examination of the data revealed striking hemispheric asymmetries that were specific to the ASD group. These findings align with mounting evidence in the autism literature of anatomic underconnectivity between the cerebral hemispheres. Years of research in individuals with TD have demonstrated that the left hemisphere (LH) is specialized toward processing local (or featural) stimulus properties and the right hemisphere (RH) toward processing global (or configural) stimulus properties. We therefore propose a model where a lack of communication between the hemispheres in ASD, combined with typical hemispheric specialization, is a root cause for impaired categorization and the oft-observed bias to process local over global stimulus properties. Copyright © 2012 Elsevier Ltd. All rights reserved.
Evolutionary Agent-based Models to design distributed water management strategies
NASA Astrophysics Data System (ADS)
Giuliani, M.; Castelletti, A.; Reed, P. M.
2012-12-01
There is growing awareness in the scientific community that the traditional centralized approach to water resources management, as described in much of the water resources literature, provides an ideal optimal solution, which is certainly useful to quantify the best physically achievable performance, but is generally inapplicable. Most real world water resources management problems are indeed characterized by the presence of multiple, distributed and institutionally-independent decision-makers. Multi-Agent Systems provide a potentially more realistic alternative framework to model multiple and self-interested decision-makers in a credible context. Each decision-maker can be represented by an agent who, being self-interested, acts according to local objective functions and produces negative externalities on system level objectives. Different levels of coordination can potentially be included in the framework by designing coordination mechanisms to drive the current decision-making structure toward the global system efficiency. Yet, the identification of effective coordination strategies can be particularly complex in modern institutional contexts and current practice is dependent on largely ad-hoc coordination strategies. In this work we propose a novel Evolutionary Agent-based Modeling (EAM) framework that enables a mapping of fully uncoordinated and centrally coordinated solutions into their relative "many-objective" tradeoffs using multiobjective evolutionary algorithms. Then, by analysing the conflicts between local individual agent and global system level objectives it is possible to more fully understand the causes, consequences, and potential solution strategies for coordination failures. Game-theoretic criteria have value for identifying the most interesting alternatives from a policy making point of view as well as the coordination mechanisms that can be applied to obtain these interesting solutions. The proposed approach is numerically tested on a synthetic case study, representing a Y-shaped system composed by two regulated lakes, whose releases merge just upstream of a city. Each reservoir is operated by an agent in order to prevent floods along the lake shores (local objective). However, the optimal operation of the reservoirs with respect to the local objectives is conflicting with the minimization of floods in the city (global objective). The evolution of the Agent-based Model from individualistic management strategies of the reservoirs toward a global compromise that reduces the costs for the city is analysed.
Song, Qi; Wu, Xiaodong; Liu, Yunlong; Smith, Mark; Buatti, John; Sonka, Milan
2009-01-01
We present a novel method for globally optimal surface segmentation of multiple mutually interacting objects, incorporating both edge and shape knowledge in a 3-D graph-theoretic approach. Hard surface interacting constraints are enforced in the interacting regions, preserving the geometric relationship of those partially interacting surfaces. The soft smoothness a priori shape compliance is introduced into the energy functional to provide shape guidance. The globally optimal surfaces can be simultaneously achieved by solving a maximum flow problem based on an arc-weighted graph representation. Representing the segmentation problem in an arc-weighted graph, one can incorporate a wider spectrum of constraints into the formulation, thus increasing segmentation accuracy and robustness in volumetric image data. To the best of our knowledge, our method is the first attempt to introduce the arc-weighted graph representation into the graph-searching approach for simultaneous segmentation of multiple partially interacting objects, which admits a globally optimal solution in a low-order polynomial time. Our new approach was applied to the simultaneous surface detection of bladder and prostate. The result was quite encouraging in spite of the low saliency of the bladder and prostate in CT images.
Characteristics of HCV positive patients in an Italian urban psychiatric unit
2006-01-01
Objectives 1) to assess the prevalence of hepatitis C virus (HCV) infection in a population of acute psychiatric in-patients; 2) to find out relationships between HCV comorbidity and clinical features of psychiatric patients. Methods Prospective observational study in a 6-year period. Results 2396 cases (1492 patients) were admitted in the considered period. Forty-two patients (2.8%) were affected by HCV infection. HCV infection was more frequent in patients with less years of education, lower social class, lower last year best Global Assessment of Functioning score, more hostile or violent behavior in hospital, with a lifetime history of previous suicide attempt, and with substance-related disorders. Conclusion HCV infection in psychiatric patients constitutes a major threat to the health of psychiatric patients and is related with unfavorable social background, worse global functioning, hostile or violent behavior, substance-related disorders. It appears also to be a significant risk of suicidal behavior. PMID:17010216
Marinangeli, Christopher P F; Jones, Peter J H
2013-06-01
Over the last decade the concept of functional foods and nutraceuticals (FFN) has gained support from various stakeholders including the food industry, scientific and academic community, government institutions or regulators, producers and consumers. However, as one begins to evaluate the global FFN industry, several issues emerge including (i) a lack of consensus across jurisdictions for acknowledging safe and efficacious FFN, (ii) challenges regarding the classification of novel food-derived bioactives as FFN or drugs, and (iii) a disconnect between nutrient requirements and dosages of FFN required to facilitate health benefits. The objectives of the present review are to discuss the role of existing stakeholders within the FFN marketplace and identify performance indicators for growth within the FFN sector. In addition, the following report provides feasible resolutions to present and future challenges facing the global FFN industry to ensure sustained long-term growth.
Ratajczak, Karina; Płomiński, Janusz
2015-01-01
The most common fracture of the distal end of the radius is Colles' fracture. Treatment modalities available for use in hand rehabilitation after injury include massage. The aim of this study was to evaluate the effect of isometric massage on the recovery of hand function in patients with Colles fractures. For this purpose, the strength of the finger flexors was assessed as an objective criterion for the evaluation of hand function. The study involved 40 patients, randomly divided into Group A of 20 patients and Group B of 20 patients. All patients received physical therapy and exercised individually with a physiotherapist. Isometric massage was additionally used in Group A. Global grip strength was assessed using a pneumatic force meter on the first and last day of therapy. Statistical analysis was performed using STATISTICA. Statistical significance was defined as a P value of less than 0.05. In both groups, global grip strength increased significantly after the therapy. There was no statistically significant difference between the groups. The men and women in both groups equally improved grip strength. A statistically significant difference was demonstrated between younger and older patients, with younger patients achieving greater gains in global grip strength in both groups. The incorporation of isometric massage in the rehabilitation plan of patients after a distal radial fracture did not significantly contribute to faster recovery of hand function or improve their quality of life.
Acoustic and elastic waveform inversion best practices
NASA Astrophysics Data System (ADS)
Modrak, Ryan T.
Reaching the global minimum of a waveform misfit function requires careful choices about the nonlinear optimization, preconditioning and regularization methods underlying an inversion. Because waveform inversion problems are susceptible to erratic convergence, one or two test cases are not enough to reliably inform such decisions. We identify best practices instead using two global, one regional and four near-surface acoustic test problems. To obtain meaningful quantitative comparisons, we carry out hundreds acoustic inversions, varying one aspect of the implementation at a time. Comparing nonlinear optimization algorithms, we find that L-BFGS provides computational savings over nonlinear conjugate gradient methods in a wide variety of test cases. Comparing preconditioners, we show that a new diagonal scaling derived from the adjoint of the forward operator provides better performance than two conventional preconditioning schemes. Comparing regularization strategies, we find that projection, convolution, Tikhonov regularization, and total variation regularization are effective in different contexts. Besides these issues, reliability and efficiency in waveform inversion depend on close numerical attention and care. Implementation details have a strong effect on computational cost, regardless of the chosen material parameterization or nonlinear optimization algorithm. Building on the acoustic inversion results, we carry out elastic experiments with four test problems, three objective functions, and four material parameterizations. The choice of parameterization for isotropic elastic media is found to be more complicated than previous studies suggests, with "wavespeed-like'' parameters performing well with phase-based objective functions and Lame parameters performing well with amplitude-based objective functions. Reliability and efficiency can be even harder to achieve in transversely isotropic elastic inversions because rotation angle parameters describing fast-axis direction are difficult to recover. Using Voigt or Chen-Tromp parameters avoids the need to include rotation angles explicitly and provides an effective strategy for anisotropic inversion. The need for flexible and portable workflow management tools for seismic inversion also poses a major challenge. In a final chapter, the software used to the carry out the above experiments is described and instructions for reproducing experimental results are given.
Rodriguez, Mabel; Spaniel, Filip; Konradova, Lucie; Sedlakova, Katerina; Dvorska, Karolina; Prajsova, Jitka; Kratochvilova, Zuzana; Levcik, David; Vlcek, Kamil; Fajnerova, Iveta
2015-01-01
Objectives: Deficit in visuospatial functions can influence both simple and complex daily life activities. Despite the fact that visuospatial deficit was reported in schizophrenia, research on visuospatial functions as an independent entity is limited. Our study aims to elucidate the impact of visuospatial deficit in comparison with verbal deficit on global functioning and quality of life in the first psychotic episode of schizophrenia spectrum disorder (FES). The significance of clinical symptoms and antipsychotic medication was also studied. Methods: Thirty-six FES patients and a matched group of healthy controls (HC group) were assessed with a neuropsychological battery focused on visuospatial (VIS) and verbal (VERB) functions. Using multiple regression analysis, we evaluated the cumulative effect of VERB and VIS functions, psychiatric symptoms (PANSS) and antipsychotic medication on global functioning (GAF) and quality of life (WHOQOL-BREF) in the FES group. Results: The FES group demonstrated significant impairment both in VIS and VERB cognitive abilities compared to the HC group. Antipsychotic medication did not significantly affect either VIS or VERB functioning. PANSS was not related to cognitive functioning, apart from the Trail Making Test B. In the FES group, the GAF score was significantly affected by the severity of positive symptoms and VERB functioning, explaining together 60% of GAF variability. The severity of negative and positive symptoms affected only the Physical health domain of WHOQOL-BREF. The degree of VERB deficit was associated with both Physical and Psychological health. Although we did not find any relation between VIS functioning, GAF, and WHOQOL-BREF, a paradoxical finding emerged in the Environment quality domain, where a worse quality of the environment was associated with better VIS functioning. Conclusions: Our results suggest that the deficit in VIS functions is an integral part of cognitive deficit in schizophrenia spectrum disorders, rather than a side effect of symptomatology or antipsychotic medication. Moreover, VERB functioning was a better predictor of GAF and WHOQOL-BREF than VIS functioning. Given the findings of negative or missing effect of VIS deficit on WHOQOL-BREF and GAF, the accuracy of these measures in evaluating the impact of global cognitive deficit on everyday life in schizophrenia could be questioned. PMID:26733828
Automatic anatomy recognition via multiobject oriented active shape models.
Chen, Xinjian; Udupa, Jayaram K; Alavi, Abass; Torigian, Drew A
2010-12-01
This paper studies the feasibility of developing an automatic anatomy recognition (AAR) system in clinical radiology and demonstrates its operation on clinical 2D images. The anatomy recognition method described here consists of two main components: (a) multiobject generalization of OASM and (b) object recognition strategies. The OASM algorithm is generalized to multiple objects by including a model for each object and assigning a cost structure specific to each object in the spirit of live wire. The delineation of multiobject boundaries is done in MOASM via a three level dynamic programming algorithm, wherein the first level is at pixel level which aims to find optimal oriented boundary segments between successive landmarks, the second level is at landmark level which aims to find optimal location for the landmarks, and the third level is at the object level which aims to find optimal arrangement of object boundaries over all objects. The object recognition strategy attempts to find that pose vector (consisting of translation, rotation, and scale component) for the multiobject model that yields the smallest total boundary cost for all objects. The delineation and recognition accuracies were evaluated separately utilizing routine clinical chest CT, abdominal CT, and foot MRI data sets. The delineation accuracy was evaluated in terms of true and false positive volume fractions (TPVF and FPVF). The recognition accuracy was assessed (1) in terms of the size of the space of the pose vectors for the model assembly that yielded high delineation accuracy, (2) as a function of the number of objects and objects' distribution and size in the model, (3) in terms of the interdependence between delineation and recognition, and (4) in terms of the closeness of the optimum recognition result to the global optimum. When multiple objects are included in the model, the delineation accuracy in terms of TPVF can be improved to 97%-98% with a low FPVF of 0.1%-0.2%. Typically, a recognition accuracy of > or = 90% yielded a TPVF > or = 95% and FPVF < or = 0.5%. Over the three data sets and over all tested objects, in 97% of the cases, the optimal solutions found by the proposed method constituted the true global optimum. The experimental results showed the feasibility and efficacy of the proposed automatic anatomy recognition system. Increasing the number of objects in the model can significantly improve both recognition and delineation accuracy. More spread out arrangement of objects in the model can lead to improved recognition and delineation accuracy. Including larger objects in the model also improved recognition and delineation. The proposed method almost always finds globally optimum solutions.
NASA Astrophysics Data System (ADS)
Ebrahimi, Mehdi; Jahangirian, Alireza
2017-12-01
An efficient strategy is presented for global shape optimization of wing sections with a parallel genetic algorithm. Several computational techniques are applied to increase the convergence rate and the efficiency of the method. A variable fidelity computational evaluation method is applied in which the expensive Navier-Stokes flow solver is complemented by an inexpensive multi-layer perceptron neural network for the objective function evaluations. A population dispersion method that consists of two phases, of exploration and refinement, is developed to improve the convergence rate and the robustness of the genetic algorithm. Owing to the nature of the optimization problem, a parallel framework based on the master/slave approach is used. The outcomes indicate that the method is able to find the global optimum with significantly lower computational time in comparison to the conventional genetic algorithm.
Wavelet-based adaptive thresholding method for image segmentation
NASA Astrophysics Data System (ADS)
Chen, Zikuan; Tao, Yang; Chen, Xin; Griffis, Carl
2001-05-01
A nonuniform background distribution may cause a global thresholding method to fail to segment objects. One solution is using a local thresholding method that adapts to local surroundings. In this paper, we propose a novel local thresholding method for image segmentation, using multiscale threshold functions obtained by wavelet synthesis with weighted detail coefficients. In particular, the coarse-to- fine synthesis with attenuated detail coefficients produces a threshold function corresponding to a high-frequency- reduced signal. This wavelet-based local thresholding method adapts to both local size and local surroundings, and its implementation can take advantage of the fast wavelet algorithm. We applied this technique to physical contaminant detection for poultry meat inspection using x-ray imaging. Experiments showed that inclusion objects in deboned poultry could be extracted at multiple resolutions despite their irregular sizes and uneven backgrounds.
Wheaton, Felicia V; Crimmins, Eileen M
2016-07-01
The objectives were to determine whether women always fare more poorly in terms of physical function and disability across countries that vary widely in terms of their level of development, epidemiologic context and level of gender equality. Sex differences in self-reported and objective measures of disability and physical function were compared among older adults aged 55-85 in the United States of America, Taiwan, Korea, Mexico, China, Indonesia and among the Tsimane of Bolivia using population-based studies collected between 2001 and 2011. Data were analysed using logistic and ordinary least-squares regression. Confidence intervals were examined to see whether the effect of being female differed significantly between countries. In all countries, women had consistently worse physical functioning (both self-reported and objectively measured). Women also tended to report more difficulty with activities of daily living (ADL), although differences were not always significant. In general, sex differences across measures were less pronounced in China. In Korea, women had significantly lower grip strength, but sex differences in ADL difficulty were non-significant or even reversed. Education and marital status helped explain sex differences. Overall, there was striking similarity in the magnitude and direction of sex differences across countries despite considerable differences in context, although modest variations in the effect of sex were observed.
Optimizing global liver function in radiation therapy treatment planning
NASA Astrophysics Data System (ADS)
Wu, Victor W.; Epelman, Marina A.; Wang, Hesheng; Romeijn, H. Edwin; Feng, Mary; Cao, Yue; Ten Haken, Randall K.; Matuszak, Martha M.
2016-09-01
Liver stereotactic body radiation therapy (SBRT) patients differ in both pre-treatment liver function (e.g. due to degree of cirrhosis and/or prior treatment) and radiosensitivity, leading to high variability in potential liver toxicity with similar doses. This work investigates three treatment planning optimization models that minimize risk of toxicity: two consider both voxel-based pre-treatment liver function and local-function-based radiosensitivity with dose; one considers only dose. Each model optimizes different objective functions (varying in complexity of capturing the influence of dose on liver function) subject to the same dose constraints and are tested on 2D synthesized and 3D clinical cases. The normal-liver-based objective functions are the linearized equivalent uniform dose (\\ell \\text{EUD} ) (conventional ‘\\ell \\text{EUD} model’), the so-called perfusion-weighted \\ell \\text{EUD} (\\text{fEUD} ) (proposed ‘fEUD model’), and post-treatment global liver function (GLF) (proposed ‘GLF model’), predicted by a new liver-perfusion-based dose-response model. The resulting \\ell \\text{EUD} , fEUD, and GLF plans delivering the same target \\ell \\text{EUD} are compared with respect to their post-treatment function and various dose-based metrics. Voxel-based portal venous liver perfusion, used as a measure of local function, is computed using DCE-MRI. In cases used in our experiments, the GLF plan preserves up to 4.6 % ≤ft(7.5 % \\right) more liver function than the fEUD (\\ell \\text{EUD} ) plan does in 2D cases, and up to 4.5 % ≤ft(5.6 % \\right) in 3D cases. The GLF and fEUD plans worsen in \\ell \\text{EUD} of functional liver on average by 1.0 Gy and 0.5 Gy in 2D and 3D cases, respectively. Liver perfusion information can be used during treatment planning to minimize the risk of toxicity by improving expected GLF; the degree of benefit varies with perfusion pattern. Although fEUD model optimization is computationally inexpensive and often achieves better GLF than \\ell \\text{EUD} model optimization does, the GLF model directly optimizes a more clinically relevant metric and can further improve fEUD plan quality.
Quantum annealing for combinatorial clustering
NASA Astrophysics Data System (ADS)
Kumar, Vaibhaw; Bass, Gideon; Tomlin, Casey; Dulny, Joseph
2018-02-01
Clustering is a powerful machine learning technique that groups "similar" data points based on their characteristics. Many clustering algorithms work by approximating the minimization of an objective function, namely the sum of within-the-cluster distances between points. The straightforward approach involves examining all the possible assignments of points to each of the clusters. This approach guarantees the solution will be a global minimum; however, the number of possible assignments scales quickly with the number of data points and becomes computationally intractable even for very small datasets. In order to circumvent this issue, cost function minima are found using popular local search-based heuristic approaches such as k-means and hierarchical clustering. Due to their greedy nature, such techniques do not guarantee that a global minimum will be found and can lead to sub-optimal clustering assignments. Other classes of global search-based techniques, such as simulated annealing, tabu search, and genetic algorithms, may offer better quality results but can be too time-consuming to implement. In this work, we describe how quantum annealing can be used to carry out clustering. We map the clustering objective to a quadratic binary optimization problem and discuss two clustering algorithms which are then implemented on commercially available quantum annealing hardware, as well as on a purely classical solver "qbsolv." The first algorithm assigns N data points to K clusters, and the second one can be used to perform binary clustering in a hierarchical manner. We present our results in the form of benchmarks against well-known k-means clustering and discuss the advantages and disadvantages of the proposed techniques.
Do infant Japanese macaques ( Macaca fuscata) categorize objects without specific training?
Murai, Chizuko; Tomonaga, Masaki; Kamegai, Kimi; Terazawa, Naoko; Yamaguchi, Masami K
2004-01-01
In the present study, we examined whether infant Japanese macaques categorize objects without any training, using a similar technique also used with human infants (the paired-preference method). During the familiarization phase, subjects were presented twice with two pairs of different objects from one global-level category. During the test phase, they were presented twice with a pair consisting of a novel familiar-category object and a novel global-level category object. The subjects were tested with three global-level categories (animal, furniture, and vehicle). It was found that they showed significant novelty preferences as a whole, indicating that they processed similarities between familiarization objects and novel familiar-category objects. These results suggest that subjects responded distinctively to objects without training, indicating the possibility that infant macaques possess the capacity for categorization.
Myer, Gregory D; Paterno, Mark V; Ford, Kevin R; Quatman, Carmen E; Hewett, Timothy E
2006-06-01
Rehabilitation following anterior cruciate ligament (ACL) reconstruction has undergone a relatively rapid and global evolution over the past 25 years. However, there is an absence of standardized, objective criteria to accurately assess an athlete's ability to progress through the end stages of rehabilitation and safe return to sport. Return-to-sport rehabilitation, progressed by quantitatively measured functional goals, may improve the athlete's integration back into sport participation. The purpose of the following clinical commentary is to introduce an example of a criteria-driven algorithm for progression through return-to-sport rehabilitation following ACL reconstruction. Our criteria-based protocol incorporates a dynamic assessment of baseline limb strength, patient-reported outcomes, functional knee stability, bilateral limb symmetry with functional tasks, postural control, power, endurance, agility, and technique with sport-specific tasks. Although this algorithm has limitations, it serves as a foundation to expand future evidence-based evaluation and to foster critical investigation into the development of objective measures to accurately determine readiness to safely return to sport following injury.
Liu, Qingshan; Wang, Jun
2011-04-01
This paper presents a one-layer recurrent neural network for solving a class of constrained nonsmooth optimization problems with piecewise-linear objective functions. The proposed neural network is guaranteed to be globally convergent in finite time to the optimal solutions under a mild condition on a derived lower bound of a single gain parameter in the model. The number of neurons in the neural network is the same as the number of decision variables of the optimization problem. Compared with existing neural networks for optimization, the proposed neural network has a couple of salient features such as finite-time convergence and a low model complexity. Specific models for two important special cases, namely, linear programming and nonsmooth optimization, are also presented. In addition, applications to the shortest path problem and constrained least absolute deviation problem are discussed with simulation results to demonstrate the effectiveness and characteristics of the proposed neural network.
NASA Astrophysics Data System (ADS)
Ye, Hong-Ling; Wang, Wei-Wei; Chen, Ning; Sui, Yun-Kang
2017-10-01
The purpose of the present work is to study the buckling problem with plate/shell topology optimization of orthotropic material. A model of buckling topology optimization is established based on the independent, continuous, and mapping method, which considers structural mass as objective and buckling critical loads as constraints. Firstly, composite exponential function (CEF) and power function (PF) as filter functions are introduced to recognize the element mass, the element stiffness matrix, and the element geometric stiffness matrix. The filter functions of the orthotropic material stiffness are deduced. Then these filter functions are put into buckling topology optimization of a differential equation to analyze the design sensitivity. Furthermore, the buckling constraints are approximately expressed as explicit functions with respect to the design variables based on the first-order Taylor expansion. The objective function is standardized based on the second-order Taylor expansion. Therefore, the optimization model is translated into a quadratic program. Finally, the dual sequence quadratic programming (DSQP) algorithm and the global convergence method of moving asymptotes algorithm with two different filter functions (CEF and PF) are applied to solve the optimal model. Three numerical results show that DSQP&CEF has the best performance in the view of structural mass and discretion.
Levin, Harvey S.; Wilde, Elisabeth A.; Chu, Zili; Yallampalli, Ragini; Hanten, Gerri R.; Li, Xiaoqi; Chia, Jon; Vasquez, Carmen; Hunter, Jill V.
2008-01-01
Objective To investigate the relation of white matter integrity using diffusion tensor imaging (DTI) to cognitive and functional outcome of moderate to severe traumatic brain injury (TBI) in children. Design Prospective observational study of children who had sustained moderate to severe TBI and a comparison group of children who had sustained orthopedic injury (OI). Participants Thirty-two children who had sustained moderate to severe TBI and 36 children with OI were studied. Methods Fiber tracking analysis of DTI acquired at 3-month postinjury and assessment of global outcome and cognitive function within 2 weeks of brain imaging. Global outcome was assessed using the Glasgow Outcome Scale and the Flanker task was used to measure cognitive processing speed and resistance to interference. Results Fractional anisotropy and apparent diffusion coefficient values differentiated the groups and both cognitive and functional outcome measures were related to the DTI findings. Dissociations were present wherein the relation of Fractional anisotropy to cognitive performance differed between the TBI and OI groups. A DTI composite measure of white matter integrity was related to global outcome in the children with TBI. Conclusions DTI is sensitive to white matter injury at 3 months following moderate to severe TBI in children, including brain regions that appear normal on conventional magnetic resonance imaging. DTI measures reflecting diffusion of water parallel and perpendicular to white matter tracts as calculated by fiber tracking analysis are related to global outcome, cognitive processing speed, and speed of resolving interference in children with moderate to severe TBI. Longitudinal data are needed to determine whether these relations between DTI and neurobehavioral outcome of TBI in children persist at longer follow-up intervals. PMID:18650764
Global Surface Temperature Change and Uncertainties Since 1861
NASA Technical Reports Server (NTRS)
Shen, Samuel S. P.; Lau, William K. M. (Technical Monitor)
2002-01-01
The objective of this talk is to analyze the warming trend and its uncertainties of the global and hemi-spheric surface temperatures. By the method of statistical optimal averaging scheme, the land surface air temperature and sea surface temperature observational data are used to compute the spatial average annual mean surface air temperature. The optimal averaging method is derived from the minimization of the mean square error between the true and estimated averages and uses the empirical orthogonal functions. The method can accurately estimate the errors of the spatial average due to observational gaps and random measurement errors. In addition, quantified are three independent uncertainty factors: urbanization, change of the in situ observational practices and sea surface temperature data corrections. Based on these uncertainties, the best linear fit to annual global surface temperature gives an increase of 0.61 +/- 0.16 C between 1861 and 2000. This lecture will also touch the topics on the impact of global change on nature and environment. as well as the latest assessment methods for the attributions of global change.
López-Pinar, Carlos; Martínez-Sanchís, Sonia; Carbonell-Vayá, Enrique; Fenollar-Cortés, Javier; Sánchez-Meca, Julio
2018-01-01
Background: Recent evidence suggests that psychosocial treatments, particularly cognitive-behavioral therapy (CBT), are effective interventions for adult attention deficit hyperactivity disorder (ADHD). The objective of this review was to determine the long-term efficacy of psychosocial interventions in improving clinically relevant variables, including ADHD core symptoms, clinical global impression (CGI), and global functioning. Methods: In total, nine randomized controlled trials and three uncontrolled single-group pretest-posttest studies were included. The data from these studies were combined using the inverse variance method. Heterogeneity and risk of bias were assessed. Subgroup analyses and meta-regressions were performed, to determine the influence of different potential moderator variables (risk of bias, medication status, follow-up length, therapy type and setting, and control group type) on effect size (ES) estimates. Results: Up to 680 of a total of 1,073 participants assessed pre-treatment were retained at follow-up. Treatment groups showed greater improvement than control groups in self-reported total ADHD symptoms, inattention, and hyperactivity/impulsivity, in addition to CGI and global functioning. Blind assessors also reported a large ES in within-subject outcomes. Studies using dialectical behavioral therapy (DBT) in a group setting, with active control matching, and that were rated as having an unclear risk of bias, achieved significantly lower ES estimates for most outcomes. Treatment effectiveness, according to the CGI measure, and global functioning were significantly increased when the percentage of medicated participants was greater. Conclusions: Our results indicate that the post-treatment gains reported in previous reviews are sustained for at least 12 months. Nevertheless, these results must be interpreted with caution, because of a high level of heterogeneity among studies and the risk of bias observed in the majority of outcomes. Thus, these findings indicate that psychological interventions are a highly valuable and stable clinical tool for the treatment of core symptoms and global functioning in adults with ADHD. PMID:29780342
López-Pinar, Carlos; Martínez-Sanchís, Sonia; Carbonell-Vayá, Enrique; Fenollar-Cortés, Javier; Sánchez-Meca, Julio
2018-01-01
Background: Recent evidence suggests that psychosocial treatments, particularly cognitive-behavioral therapy (CBT), are effective interventions for adult attention deficit hyperactivity disorder (ADHD). The objective of this review was to determine the long-term efficacy of psychosocial interventions in improving clinically relevant variables, including ADHD core symptoms, clinical global impression (CGI), and global functioning. Methods: In total, nine randomized controlled trials and three uncontrolled single-group pretest-posttest studies were included. The data from these studies were combined using the inverse variance method. Heterogeneity and risk of bias were assessed. Subgroup analyses and meta-regressions were performed, to determine the influence of different potential moderator variables (risk of bias, medication status, follow-up length, therapy type and setting, and control group type) on effect size (ES) estimates. Results: Up to 680 of a total of 1,073 participants assessed pre-treatment were retained at follow-up. Treatment groups showed greater improvement than control groups in self-reported total ADHD symptoms, inattention, and hyperactivity/impulsivity, in addition to CGI and global functioning. Blind assessors also reported a large ES in within-subject outcomes. Studies using dialectical behavioral therapy (DBT) in a group setting, with active control matching, and that were rated as having an unclear risk of bias, achieved significantly lower ES estimates for most outcomes. Treatment effectiveness, according to the CGI measure, and global functioning were significantly increased when the percentage of medicated participants was greater. Conclusions: Our results indicate that the post-treatment gains reported in previous reviews are sustained for at least 12 months. Nevertheless, these results must be interpreted with caution, because of a high level of heterogeneity among studies and the risk of bias observed in the majority of outcomes. Thus, these findings indicate that psychological interventions are a highly valuable and stable clinical tool for the treatment of core symptoms and global functioning in adults with ADHD.
NASA Astrophysics Data System (ADS)
Łatas, Waldemar
2018-01-01
The problem of vibrations of the beam with the attached system of translational and rotational dynamic mass dampers subjected to random excitations with peaked power spectral densities, is presented in the hereby paper. The Euler-Bernoulli beam model is applied, while for solving the equation of motion the Galerkin method and the Laplace time transform are used. The obtained transfer functions allow to determine power spectral densities of the beam deflection and other dependent variables. Numerical examples present simple optimization problems of mass dampers parameters for local and global objective functions.
NASA Technical Reports Server (NTRS)
Madavan, Nateri K.
2004-01-01
Differential Evolution (DE) is a simple, fast, and robust evolutionary algorithm that has proven effective in determining the global optimum for several difficult single-objective optimization problems. The DE algorithm has been recently extended to multiobjective optimization problem by using a Pareto-based approach. In this paper, a Pareto DE algorithm is applied to multiobjective aerodynamic shape optimization problems that are characterized by computationally expensive objective function evaluations. To improve computational expensive the algorithm is coupled with generalized response surface meta-models based on artificial neural networks. Results are presented for some test optimization problems from the literature to demonstrate the capabilities of the method.
Cha, Danielle S; Carmona, Nicole E; Mansur, Rodrigo B; Lee, Yena; Park, Hyun Jung; Rodrigues, Nelson B; Subramaniapillai, Mehala; Rosenblat, Joshua D; Pan, Zihang; Lee, Jae Hon; Lee, JungGoo; Almatham, Fahad; Alageel, Asem; Shekotikhina, Margarita; Zhou, Aileen J; Rong, Carola; Harrison, John; McIntyre, Roger S
2017-04-01
To examine the role of pain on cognitive function in adults with major depressive disorder (MDD). Adults (18-65) with a Diagnostic and Statistical Manual - Fifth Edition (DSM-5)-defined diagnosis of MDD experiencing a current major depressive episode (MDE) were enrolled (n MDD =100). All subjects with MDD were matched in age, sex, and years of education to healthy controls (HC) (n HC =100) for comparison. Cognitive function was assessed using the recently validated THINC-integrated tool (THINC-it), which comprises variants of the choice reaction time (i.e., THINC-it: Spotter), One-Back (i.e., THINC-it: Symbol Check), Digit Symbol Substitution Test (i.e., THINC-it: Codebreaker), Trail Making Test - Part B (i.e., THINC-it: Trails), as well as the Perceived Deficits Questionnaire for Depression - 5-item (i.e., THINC-it: PDQ-5-D). A global index of objective cognitive function was computed using objective measures from the THINC-it, while self-rated cognitive deficits were measured using the PDQ-5-D. Pain was measured using a Visual Analogue Scale (VAS). Regression analyses evaluated the role of pain in predicting objective and subjective cognitive function. A significant between-group differences on the VAS was observed (p<0.001), with individuals with MDD reporting higher pain severity as evidenced by higher scores on the VAS than HC. Significant interaction effects were observed between self -rated cognitive deficits and pain ratings (p<0.001) on objective cognitive performance (after adjusting for MADRS total score), suggesting that pain moderates the association between self-rated and objective cognitive function. Results indicated that pain is associated with increased self-rated and objective cognitive deficits in adults with MDD. The study herein provides preliminary evidence demonstrating that adults with MDD reporting pain symptomatology and poorer subjective cognitive function is predictive of poorer objective cognitive performance. THINC-it is capable of detecting cognitive dysfunction amongst adults with MDD and pain. Copyright © 2017 Scandinavian Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Development of a Global Wetland Sustainability Index for comprehensive land use planning
NASA Astrophysics Data System (ADS)
Schleupner, C.; Schneider, U. A.; Havlik, P.; Stacke, T.
2012-04-01
Allocation of nature reserves for conservation of ecosystem functions and services is a multi-dimensional task. Conservation programs act from local to regional or national scales, and some efforts involve entire continents. Globally, several international environmental agreements have been established which include conservation issues. Examples are the Convention on Biological Diversity, the Convention on Migratory Species of Wild Animals, the UN Framework Convention on Climate Change, and the Ramsar Convention on Wetlands. A common aim of most initiatives is the protection and restoration of valuable natural sites by providing a functional network of sites. The planning of protected habitat networks to safeguard global biodiversity requires substantial knowledge on exposure, services, and functions of ecosystems. Further, the complex spatial relationships between humans and the environment under consideration of costs and land use competition have to be determined. Often such analyses are hindered by lack of data. We developed a global index that ranks sites for wetland protection according to its wetland quantity, wetland quality and pressure upon the wetland sites. Each of the three parts is based on several spatial-ecological datasets that contain important information for the adequate assessment of spatial economic and ecologic interdependencies. Applying cluster analyses and ecological decision trees the data are combined and results are translated to the final index and expressed per simulation unit for integration into the Global Biomass Optimization Model GLOBIOM. This global recursive dynamic partial equilibrium model integrates the agricultural, bio energy and forestry sectors with the aim to provide policy analyses on global issues concerning land use competition between the major land-based production sectors. Results not only show the most vulnerable wetland areas to nature loss and the most valuable wetland areas for biodiversity protection under certain land use scenarios. Moreover, costs of protection are estimated and the results give recommendations for action by illustrating wetland conservation areas in need for conservation. Often wetlands provide numerous ecosystem services to society, such as water retention, flood control, water purification, to name only a few. The sustainable conservation of wetland sites, especially in highly human dominated landscapes, is therefore an important global but still underestimated objective.
Multi-Objective Community Detection Based on Memetic Algorithm
2015-01-01
Community detection has drawn a lot of attention as it can provide invaluable help in understanding the function and visualizing the structure of networks. Since single objective optimization methods have intrinsic drawbacks to identifying multiple significant community structures, some methods formulate the community detection as multi-objective problems and adopt population-based evolutionary algorithms to obtain multiple community structures. Evolutionary algorithms have strong global search ability, but have difficulty in locating local optima efficiently. In this study, in order to identify multiple significant community structures more effectively, a multi-objective memetic algorithm for community detection is proposed by combining multi-objective evolutionary algorithm with a local search procedure. The local search procedure is designed by addressing three issues. Firstly, nondominated solutions generated by evolutionary operations and solutions in dominant population are set as initial individuals for local search procedure. Then, a new direction vector named as pseudonormal vector is proposed to integrate two objective functions together to form a fitness function. Finally, a network specific local search strategy based on label propagation rule is expanded to search the local optimal solutions efficiently. The extensive experiments on both artificial and real-world networks evaluate the proposed method from three aspects. Firstly, experiments on influence of local search procedure demonstrate that the local search procedure can speed up the convergence to better partitions and make the algorithm more stable. Secondly, comparisons with a set of classic community detection methods illustrate the proposed method can find single partitions effectively. Finally, the method is applied to identify hierarchical structures of networks which are beneficial for analyzing networks in multi-resolution levels. PMID:25932646
Multi-objective community detection based on memetic algorithm.
Wu, Peng; Pan, Li
2015-01-01
Community detection has drawn a lot of attention as it can provide invaluable help in understanding the function and visualizing the structure of networks. Since single objective optimization methods have intrinsic drawbacks to identifying multiple significant community structures, some methods formulate the community detection as multi-objective problems and adopt population-based evolutionary algorithms to obtain multiple community structures. Evolutionary algorithms have strong global search ability, but have difficulty in locating local optima efficiently. In this study, in order to identify multiple significant community structures more effectively, a multi-objective memetic algorithm for community detection is proposed by combining multi-objective evolutionary algorithm with a local search procedure. The local search procedure is designed by addressing three issues. Firstly, nondominated solutions generated by evolutionary operations and solutions in dominant population are set as initial individuals for local search procedure. Then, a new direction vector named as pseudonormal vector is proposed to integrate two objective functions together to form a fitness function. Finally, a network specific local search strategy based on label propagation rule is expanded to search the local optimal solutions efficiently. The extensive experiments on both artificial and real-world networks evaluate the proposed method from three aspects. Firstly, experiments on influence of local search procedure demonstrate that the local search procedure can speed up the convergence to better partitions and make the algorithm more stable. Secondly, comparisons with a set of classic community detection methods illustrate the proposed method can find single partitions effectively. Finally, the method is applied to identify hierarchical structures of networks which are beneficial for analyzing networks in multi-resolution levels.
Sander, Angelle M; Maestas, Kacey Little; Nick, Todd G; Pappadis, Monique R; Hammond, Flora M; Hanks, Robin A; Ripley, David L
2013-01-01
To investigate predictors of sexual functioning 1 year following traumatic brain injury (TBI). Prospective cohort study. Community. A total of 255 persons with TBI (187 males; 68 females) who had been treated at 1 of 6 TBI Model Systems inpatient rehabilitation units and were living in the community. Derogatis Interview for Sexual Functioning-Self-Report (DISF-SR); Global Satisfaction With Sexual Functioning (Global Sexual Satisfaction Index); Participation Assessment With Recombined Tools-Objective; Patient Health Questionnaire-9. Older age, female gender, and more severe injury were associated with greater sexual dysfunction 1 year following injury. As age increased from 24 to 49 years, the odds of sexual impairment increased more than 3-fold (95% confidence interval: 1.82-5.88). Females had a 2.5 increase in odds of sexual impairment compared with males (95% confidence interval: 1.23-5.26). Greater social participation was predictive of better sexual functioning. Dissatisfaction with sexual functioning was predicted by older age and depression. Older persons and females appear to be at greater risk for sexual dysfunction after TBI and may benefit from specialized assessment and treatment services. Relationships were identified between social participation and sexual function and between depression and sexual satisfaction that may serve as clinical indicators for further assessment and intervention. Further research is needed to elucidate these relationships and identify effective clinical approaches.
Association between late-life social activity and motor decline in older adults.
Buchman, Aron S; Boyle, Patricia A; Wilson, Robert S; Fleischman, Debra A; Leurgans, Sue; Bennett, David A
2009-06-22
Loss of motor function is a common consequence of aging, but little is known about the factors that predict idiopathic motor decline. Our objective was to test the hypothesis that late-life social activity is related to the rate of change in motor function in old age. Longitudinal cohort study with a mean follow-up of 4.9 years with 906 persons without stroke, Parkinson disease, or dementia participating in the Rush Memory and Aging Project. At baseline, participants rated the frequency of their current participation in common social activities from which a summary measure of social activity was derived. The main outcome measure was annual change in a composite measure of global motor function, based on 9 measures of muscle strength and 9 motor performances. Mean (SD) social activity score at baseline was 2.6 (0.58), with higher scores indicating more frequent participation in social activities. In a generalized estimating equation model, controlling for age, sex, and education, global motor function declined by approximately 0.05 U/y (estimate, 0.016; 95% confidence interval [CI], -0.057 to 0.041 [P = .02]). Each 1-point decrease in social activity was associated with approximately a 33% more rapid rate of decline in motor function (estimate, 0.016; 95% CI, 0.003 to 0.029 [P = .02]). The effect of each 1-point decrease in the social activity score at baseline on the rate of change in global motor function was the same as being approximately 5 years older at baseline (age estimate, -0.003; 95% CI, -0.004 to -0.002 [P<.001]). Furthermore, this amount of motor decline per year was associated with a more than 40% increased risk of death (hazard ratio, 1.44; 95% CI, 1.30 to 1.60) and a 65% increased risk of incident Katz disability (hazard ratio, 1.65; 95% CI, 1.48 to 1.83). The association of social activity with the rate of global motor decline did not vary along demographic lines and was unchanged (estimate, 0.025; 95% CI, 0.005 to 0.045 [P = .01]) after controlling for potential confounders including late-life physical and cognitive activity, disability, global cognition depressive symptoms, body composition, and chronic medical conditions. Less frequent participation in social activities is associated with a more rapid rate of motor function decline in old age.
Pirogovsky, Eva; Martinez-Hannon, Mercedes; Schiehser, Dawn M; Lessig, Stephanie L; Song, David D; Litvan, Irene; Filoteo, J Vincent
2013-01-01
Few studies have examined instrumental activities of daily living (iADLs) in nondemented Parkinson's disease (PD), and the majority of these studies have used report-based measures, which can have limited validity. The present study had two main goals: (a) to examine the performance of nondemented PD patients on two performance-based measures of iADLs, which are considered more objective functional measures, and (b) to examine the cognitive, motor, and psychiatric correlates of iADL impairment in PD. Ninety-eight nondemented PD patients and 47 healthy older adults were administered performance-based measures that assess the ability to manage medications (Medication Management Ability Assessment) and finances (University of California, San Diego, UCSD, Performance-based Skills Assessment), the Mattis Dementia Rating Scale to assess global cognitive functioning, the Unified Parkinson's Disease Rating Scale Part III to assess motor symptom severity, and the Geriatric Depression Scale to assess depressive symptoms. Nondemented PD patients demonstrated significantly impaired scores relative to the healthy comparison group on the performance-based measure of financial management, but there were no significant group differences in medication management. Global cognitive functioning, motor severity, and depressive symptoms did not correlate with scores on either of the functional measures, except for a small correlation between depressive symptoms and financial management. The two performance-based measures of iADL functioning did not correlate with one another. These findings suggest that medication and financial management may not be predicted based on global cognitive functioning and that iADLs may not be represented by a single construct. Furthermore, these findings suggest the potential need for a multidimensional approach to assessing iADLs.
Online Feature Transformation Learning for Cross-Domain Object Category Recognition.
Zhang, Xuesong; Zhuang, Yan; Wang, Wei; Pedrycz, Witold
2017-06-09
In this paper, we introduce a new research problem termed online feature transformation learning in the context of multiclass object category recognition. The learning of a feature transformation is viewed as learning a global similarity metric function in an online manner. We first consider the problem of online learning a feature transformation matrix expressed in the original feature space and propose an online passive aggressive feature transformation algorithm. Then these original features are mapped to kernel space and an online single kernel feature transformation (OSKFT) algorithm is developed to learn a nonlinear feature transformation. Based on the OSKFT and the existing Hedge algorithm, a novel online multiple kernel feature transformation algorithm is also proposed, which can further improve the performance of online feature transformation learning in large-scale application. The classifier is trained with k nearest neighbor algorithm together with the learned similarity metric function. Finally, we experimentally examined the effect of setting different parameter values in the proposed algorithms and evaluate the model performance on several multiclass object recognition data sets. The experimental results demonstrate the validity and good performance of our methods on cross-domain and multiclass object recognition application.
Tomographic imaging using poissonian detector data
Aspelmeier, Timo; Ebel, Gernot; Hoeschen, Christoph
2013-10-15
An image reconstruction method for reconstructing a tomographic image (f.sub.j) of a region of investigation within an object (1), comprises the steps of providing detector data (y.sub.i) comprising Poisson random values measured at an i-th of a plurality of different positions, e.g. i=(k,l) with pixel index k on a detector device and angular index l referring to both the angular position (.alpha..sub.l) and the rotation radius (r.sub.l) of the detector device (10) relative to the object (1), providing a predetermined system matrix A.sub.ij assigning a j-th voxel of the object (1) to the i-th detector data (y.sub.i), and reconstructing the tomographic image (f.sub.j) based on the detector data (y.sub.i), said reconstructing step including a procedure of minimizing a functional F(f) depending on the detector data (y.sub.i) and the system matrix A.sub.ij and additionally including a sparse or compressive representation of the object (1) in an orthobasis T, wherein the tomographic image (f.sub.j) represents the global minimum of the functional F(f). Furthermore, an imaging method and an imaging device using the image reconstruction method are described.
Inequality, income, and poverty: comparative global evidence.
Fosu, Augustin Kwasi
2010-01-01
Objectives. The study seeks to provide comparative global evidence on the role of income inequality, relative to income growth, in poverty reduction.Methods. An analysis-of-covariance model is estimated using a large global sample of 1980–2004 unbalanced panel data, with the headcount measure of poverty as the dependent variable, and the Gini coefficient and PPP-adjusted mean income as explanatory variables. Both random-effects and fixed-effects methods are employed in the estimation.Results. The responsiveness of poverty to income is a decreasing function of inequality, and the inequality elasticity of poverty is actually larger than the income elasticity of poverty. Furthermore, there is a large variation across regions (and countries) in the relative effects of inequality on poverty.Conclusion. Income distribution plays a more important role than might be traditionally acknowledged in poverty reduction, though this importance varies widely across regions and countries.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Krityakierne, Tipaluck; Akhtar, Taimoor; Shoemaker, Christine A.
This paper presents a parallel surrogate-based global optimization method for computationally expensive objective functions that is more effective for larger numbers of processors. To reach this goal, we integrated concepts from multi-objective optimization and tabu search into, single objective, surrogate optimization. Our proposed derivative-free algorithm, called SOP, uses non-dominated sorting of points for which the expensive function has been previously evaluated. The two objectives are the expensive function value of the point and the minimum distance of the point to previously evaluated points. Based on the results of non-dominated sorting, P points from the sorted fronts are selected as centersmore » from which many candidate points are generated by random perturbations. Based on surrogate approximation, the best candidate point is subsequently selected for expensive evaluation for each of the P centers, with simultaneous computation on P processors. Centers that previously did not generate good solutions are tabu with a given tenure. We show almost sure convergence of this algorithm under some conditions. The performance of SOP is compared with two RBF based methods. The test results show that SOP is an efficient method that can reduce time required to find a good near optimal solution. In a number of cases the efficiency of SOP is so good that SOP with 8 processors found an accurate answer in less wall-clock time than the other algorithms did with 32 processors.« less
NASA Astrophysics Data System (ADS)
An, M.; Assumpcao, M.
2003-12-01
The joint inversion of receiver function and surface wave is an effective way to diminish the influences of the strong tradeoff among parameters and the different sensitivity to the model parameters in their respective inversions, but the inversion problem becomes more complex. Multi-objective problems can be much more complicated than single-objective inversion in the model selection and optimization. If objectives are involved and conflicting, models can be ordered only partially. In this case, Pareto-optimal preference should be used to select solutions. On the other hand, the inversion to get only a few optimal solutions can not deal properly with the strong tradeoff between parameters, the uncertainties in the observation, the geophysical complexities and even the incompetency of the inversion technique. The effective way is to retrieve the geophysical information statistically from many acceptable solutions, which requires more competent global algorithms. Competent genetic algorithms recently proposed are far superior to the conventional genetic algorithm and can solve hard problems quickly, reliably and accurately. In this work we used one of competent genetic algorithms, Bayesian Optimization Algorithm as the main inverse procedure. This algorithm uses Bayesian networks to draw out inherited information and can use Pareto-optimal preference in the inversion. With this algorithm, the lithospheric structure of Paran"› basin is inverted to fit both the observations of inter-station surface wave dispersion and receiver function.
Systems Proteomics for Translational Network Medicine
Arrell, D. Kent; Terzic, Andre
2012-01-01
Universal principles underlying network science, and their ever-increasing applications in biomedicine, underscore the unprecedented capacity of systems biology based strategies to synthesize and resolve massive high throughput generated datasets. Enabling previously unattainable comprehension of biological complexity, systems approaches have accelerated progress in elucidating disease prediction, progression, and outcome. Applied to the spectrum of states spanning health and disease, network proteomics establishes a collation, integration, and prioritization algorithm to guide mapping and decoding of proteome landscapes from large-scale raw data. Providing unparalleled deconvolution of protein lists into global interactomes, integrative systems proteomics enables objective, multi-modal interpretation at molecular, pathway, and network scales, merging individual molecular components, their plurality of interactions, and functional contributions for systems comprehension. As such, network systems approaches are increasingly exploited for objective interpretation of cardiovascular proteomics studies. Here, we highlight network systems proteomic analysis pipelines for integration and biological interpretation through protein cartography, ontological categorization, pathway and functional enrichment and complex network analysis. PMID:22896016
NASA Astrophysics Data System (ADS)
Mouffe, M.; Getirana, A.; Ricci, S. M.; Lion, C.; Biancamaria, S.; Boone, A.; Mognard, N. M.; Rogel, P.
2011-12-01
The Surface Water and Ocean Topography (SWOT) mission is a swath mapping radar interferometer that will provide global measurements of water surface elevation (WSE). The revisit time depends upon latitude and varies from two (low latitudes) to ten (high latitudes) per 22-day orbit repeat period. The high resolution and the global coverage of the SWOT data open the way for new hydrology studies. Here, the aim is to investigate the use of virtually generated SWOT data to improve discharge simulation using data assimilation techniques. In the framework of the SWOT virtual mission (VM), this study presents the first results of the automatic calibration of a global flow routing (GFR) scheme using SWOT VM measurements for the Amazon basin. The Hydrological Modeling and Analysis Platform (HyMAP) is used along with the MOCOM-UA multi-criteria global optimization algorithm. HyMAP has a 0.25-degree spatial resolution and runs at the daily time step to simulate discharge, water levels and floodplains. The surface runoff and baseflow drainage derived from the Interactions Sol-Biosphère-Atmosphère (ISBA) model are used as inputs for HyMAP. Previous works showed that the use of ENVISAT data enables the reduction of the uncertainty on some of the hydrological model parameters, such as river width and depth, Manning roughness coefficient and groundwater time delay. In the framework of the SWOT preparation work, the automatic calibration procedure was applied using SWOT VM measurements. For this Observing System Experiment (OSE), the synthetical data were obtained applying an instrument simulator (representing realistic SWOT errors) for one hydrological year to HYMAP simulated WSE using a "true" set of parameters. Only pixels representing rivers larger than 100 meters within the Amazon basin are considered to produce SWOT VM measurements. The automatic calibration procedure leads to the estimation of optimal parametersminimizing objective functions that formulate the difference between SWOT observations and modeled WSE using a perturbed set of parameters. Different formulations of the objective function were used, especially to account for SWOT observation errors, as well as various sets of calibration parameters.
Executive function in fibromyalgia: Comparing subjective and objective measures.
Gelonch, Olga; Garolera, Maite; Valls, Joan; Rosselló, Lluís; Pifarré, Josep
2016-04-01
There is evidence to suggest the existence of an executive dysfunction in people diagnosed with fibromyalgia, although there are certain inconsistencies between studies. Here, we aim to compare executive performance between patients with fibromyalgia and a control group by using subjective and objective cognitive tests, analyzing the influence of patient mood on the results obtained, and studying associations between the two measures. 82 patients diagnosed with fibromyalgia and 42 healthy controls, matched by age and years of education, were assessed using the Behavioral Rating Inventory of Executive Function - Adult Version (BRIEF-A) as a subjective measure of executive functioning. A selection of objective cognitive tests were also used to measure a series of executive functions and to identify symptoms of depression and anxiety. Patients with fibromyalgia perceived greater difficulties than the control group on all of the BRIEF-A scales. However, after adjustments were made for depression and anxiety the only differences that remained were those associated with the working memory scale and the Metacognition and Global Executive Composite index. In the case of the objective cognitive tests, a significantly worse overall performance was evidenced for the fibromyalgia patients. However, this also disappeared when adjustments were made for depression and anxiety. After this adjustment, fibromyalgia patients only performed significantly worse for the interference effect in the Stroop Test. Although there were no significant associations between most of the objective cognitive tests and the BRIEF-A scales, depression and anxiety exhibited strong associations with almost all of the BRIEF-A scales and with several of the objective cognitive tests. Patients with fibromyalgia showed executive dysfunction in subjective and objective measures, although most of this impairment was associated with mood disturbances. Exceptions to this general rule were observed in the impairment of working memory evidenced on the BRIEF-A scale and the inhibition impairment exhibited by the interference effect from the Stroop Test. The two types of measurement provide different yet complementary information. Copyright © 2016 Elsevier Inc. All rights reserved.
Oliveira-Maia, Albino J; Mendonça, Carina; Pessoa, Maria J; Camacho, Marta; Gago, Joaquim
2016-01-01
Within clinical psychiatry, recovery from severe mental illness (SMI) has classically been defined according to symptoms and function (service-based recovery). However, service-users have argued that recovery should be defined as the process of overcoming mental illness, regaining self-control and establishing a meaningful life (customer-based recovery). Here, we aimed to compare customer-based and service-based recovery and clarify their differential relationship with other constructs, namely needs and quality of life. The study was conducted in 101 patients suffering from SMI, recruited from a rural community mental health setting in Portugal. Customer-based recovery and function-related service-based recovery were assessed, respectively, using a shortened version of the Mental Health Recovery Measure (MHRM-20) and the Global Assessment of Functioning score. The Camberwell Assessment of Need scale was used to objectively assess needs, while subjective quality of life was measured with the TL-30s scale. Using multiple linear regression models, we found that the Global Assessment of Functioning score was incrementally predictive of the MHRM-20 score, when added to a model including only clinical and demographic factors, and that this model was further incremented by the score for quality of life. However, in an alternate model using the Global Assessment of Functioning score as the dependent variable, while the MHRM-20 score contributed significantly to the model when added to clinical and demographic factors, the model was not incremented by the score for quality of life. These results suggest that, while a more global concept of recovery from SMI may be assessed using measures for service-based and customer-based recovery, the latter, namely the MHRM-20, also provides information about subjective well-being. Pending confirmation of these findings in other populations, this instrument could thus be useful for comprehensive assessment of recovery and subjective well-being in patients suffering from SMI.
Amarapurkar, Deepak N; Rane, Priya
2004-12-01
Prokinetic agents like itopride hydrochloride and mosapride citrate are commonly used in the management of functional dyspepsia. However, in a recently conducted international, multicentric study, efficacy of 3 different regimens of mosapride was shown to be comparable to placebo. The objective of this phase 4 randomised, double blind, prospective study was to compare the efficacy and safety of ganaton (itopride hydrochloride) and mosapride citrate in the management of functional dyspepsia among patients attending the gastroenterology outpatient department of a tertiary care hospital. Ganaton 50 mg or mosapride citrate 5 mg three times daily before meals for a period of 2 weeks was administered orally. Thirty functional dyspepsia patients in each group (total = 60) were randomised to receive itopride hydrochloride or mosapride citrate treatment for 2 weeks. In itopride versus mosapride groups, global efficacy as judged by patients was excellent in 17 versus 9 (p < 0.05) and poor in 0 versus 3 (p < 0.05). In itopride versus mosapride group global efficacy as judged by physician was excellent in 24 (80%) versus 15 (50%) and poor in 0 (0%) versus 3 (10%) patients respectively. The global efficacy was rated as excellent to good in significantly (p < 0.05) more number of patients in itopride (93.3%) group as compared to mosapride (63.33 %) group. None of the patients reported any adverse events with itopride treatment. In the mosapride group 5 patients (16.7%) reported adverse events. Two patients (6.7%) were withdrawn from mosapride treatment due to adverse events. The physician rated global tolerability ofitopride versus mosapride treatment as excellent in 23 (76.7%) versus 8 (26.7%) (p < 0.05) and poor in 0 (0%) versus 6 (20%) patients respectively. It may be concluded that ganaton (itopride hydrochloride) is superior in efficacy and safety over mosapride citrate in the management of functional dyspepsia.
Oliveira-Maia, Albino J.; Mendonça, Carina; Pessoa, Maria J.; Camacho, Marta; Gago, Joaquim
2016-01-01
Within clinical psychiatry, recovery from severe mental illness (SMI) has classically been defined according to symptoms and function (service-based recovery). However, service-users have argued that recovery should be defined as the process of overcoming mental illness, regaining self-control and establishing a meaningful life (customer-based recovery). Here, we aimed to compare customer-based and service-based recovery and clarify their differential relationship with other constructs, namely needs and quality of life. The study was conducted in 101 patients suffering from SMI, recruited from a rural community mental health setting in Portugal. Customer-based recovery and function-related service-based recovery were assessed, respectively, using a shortened version of the Mental Health Recovery Measure (MHRM-20) and the Global Assessment of Functioning score. The Camberwell Assessment of Need scale was used to objectively assess needs, while subjective quality of life was measured with the TL-30s scale. Using multiple linear regression models, we found that the Global Assessment of Functioning score was incrementally predictive of the MHRM-20 score, when added to a model including only clinical and demographic factors, and that this model was further incremented by the score for quality of life. However, in an alternate model using the Global Assessment of Functioning score as the dependent variable, while the MHRM-20 score contributed significantly to the model when added to clinical and demographic factors, the model was not incremented by the score for quality of life. These results suggest that, while a more global concept of recovery from SMI may be assessed using measures for service-based and customer-based recovery, the latter, namely the MHRM-20, also provides information about subjective well-being. Pending confirmation of these findings in other populations, this instrument could thus be useful for comprehensive assessment of recovery and subjective well-being in patients suffering from SMI. PMID:27857698
Kluger, Benzi M.; Brown, R. Preston; Aerts, Shanae; Schenkman, Margaret
2014-01-01
Background Parkinson disease (PD) may lead to functional limitations through both motor and non-motor symptoms. While patients with advanced disease have well-documented and profound functional limitations, less is known about the determinants of function in early to mid-stage disease where interventions may be more likely to benefit and preserve function. Objective The objective of the current study was to identify motor, cognitive and gait determinants of physical functional performance in patients with early to mid-stage PD. Design Secondary analysis of cross-sectional baseline data from a randomized clinical trial of exercise. Setting Tertiary academic medical center. Participants 121 patients with early to mid-stage PD. Methods Our functional performance outcomes included: 1) the Continuous Scale Functional Performance Test (CS-PFP; primary outcome); 2) the timed up and go (TUG) tests; and Section 2 (Activities of Daily Living) of the Unified Parkinson's Disease Rating Scale (UPDRS). Explanatory variables included measures of disease severity, motor function, cognitive function, balance and gait. Step-wise linear regression models were used to determine correlations between explanatory variables and outcome measures. Results In our regression models the CS-PFP significantly correlated with walking endurance (six minute walk; r2 = 0.12, p < .0001), turning ability (360 degree turn; r2 = .03, p = .002), attention (brief test of attention; r2 = .01, p = .03), overall cognitive status (Mini-mental State Examination; r2 = .01, p = .04) and bradykinesia (timed tapping; r2 = .02, p = .02). The TUG significantly correlated with walking speed (5 meter walk; r2 = 0.33, p <.0001), stride length (r2 = 0.25, p <.0001), turning ability (360 turn r2 = .05, p = .0003) and attention (r2 = .016, p = .03). Section 2 of the UPDRS was significantly correlated with endurance (r2 = .09, p < .0001), turning ability (r2 = .03, p = .001) and attention (r2 = .01, p = .03). Conclusions Gait, motor and cognitive function all contribute to objectively measured global functional ability in mild to moderate PD. Subjectively measured functional activity outcomes may underestimate the impact of both motor and non-motor symptoms. PMID:24880056
Sleep Extension Improves Neurocognitive Functions in Chronically Sleep-Deprived Obese Individuals
Lucassen, Eliane A.; Piaggi, Paolo; Dsurney, John; de Jonge, Lilian; Zhao, Xiong-ce; Mattingly, Megan S.; Ramer, Angela; Gershengorn, Janet; Csako, Gyorgy; Cizza, Giovanni
2014-01-01
Background Sleep deprivation and obesity, are associated with neurocognitive impairments. Effects of sleep deprivation and obesity on cognition are unknown, and the cognitive long-term effects of improvement of sleep have not been prospectively assessed in short sleeping, obese individuals. Objective To characterize neurocognitive functions and assess its reversibility. Design Prospective cohort study. Setting Tertiary Referral Research Clinical Center. Patients A cohort of 121 short-sleeping (<6.5 h/night) obese (BMI 30–55 kg/m2) men and pre-menopausal women. Intervention Sleep extension (468±88 days) with life-style modifications. Measurements Neurocognitive functions, sleep quality and sleep duration. Results At baseline, 44% of the individuals had an impaired global deficit score (t-score 0–39). Impaired global deficit score was associated with worse subjective sleep quality (p = 0.02), and lower urinary dopamine levels (p = 0.001). Memory was impaired in 33%; attention in 35%; motor skills in 42%; and executive function in 51% of individuals. At the final evaluation (N = 74), subjective sleep quality improved by 24% (p<0.001), self-reported sleep duration increased by 11% by questionnaires (p<0.001) and by 4% by diaries (p = 0.04), and daytime sleepiness tended to improve (p = 0.10). Global cognitive function and attention improved by 7% and 10%, respectively (both p = 0.001), and memory and executive functions tended to improve (p = 0.07 and p = 0.06). Serum cortisol increased by 17% (p = 0.02). In a multivariate mixed model, subjective sleep quality and sleep efficiency, urinary free cortisol and dopamine and plasma total ghrelin accounted for 1/5 of the variability in global cognitive function. Limitations Drop-out rate. Conclusions Chronically sleep-deprived obese individuals exhibit substantial neurocognitive deficits that are partially reversible upon improvement of sleep in a non-pharmacological way. These findings have clinical implications for large segments of the US population. Trail registration www.ClinicalTrials.gov NCT00261898. NIDDK protocol 06-DK-0036 PMID:24482677
Clonal selection versus clonal cooperation: the integrated perception of immune objects
Nataf, Serge
2016-01-01
Analogies between the immune and nervous systems were first envisioned by the immunologist Niels Jerne who introduced the concepts of antigen "recognition" and immune "memory". However, since then, it appears that only the cognitive immunology paradigm proposed by Irun Cohen, attempted to further theorize the immune system functions through the prism of neurosciences. The present paper is aimed at revisiting this analogy-based reasoning. In particular, a parallel is drawn between the brain pathways of visual perception and the processes allowing the global perception of an "immune object". Thus, in the visual system, distinct features of a visual object (shape, color, motion) are perceived separately by distinct neuronal populations during a primary perception task. The output signals generated during this first step instruct then an integrated perception task performed by other neuronal networks. Such a higher order perception step is by essence a cooperative task that is mandatory for the global perception of visual objects. Based on a re-interpretation of recent experimental data, it is suggested that similar general principles drive the integrated perception of immune objects in secondary lymphoid organs (SLOs). In this scheme, the four main categories of signals characterizing an immune object (antigenic, contextual, temporal and localization signals) are first perceived separately by distinct networks of immunocompetent cells. Then, in a multitude of SLO niches, the output signals generated during this primary perception step are integrated by TH-cells at the single cell level. This process eventually generates a multitude of T-cell and B-cell clones that perform, at the scale of SLOs, an integrated perception of immune objects. Overall, this new framework proposes that integrated immune perception and, consequently, integrated immune responses, rely essentially on clonal cooperation rather than clonal selection. PMID:27830060
Rethinking the 'global' in global health: a dialectic approach
2010-01-01
Background Current definitions of 'global health' lack specificity about the term 'global'. This debate presents and discusses existing definitions of 'global health' and a common problem inherent therein. It aims to provide a way forward towards an understanding of 'global health' while avoiding redundancy. The attention is concentrated on the dialectics of different concepts of 'global' in their application to malnutrition; HIV, tuberculosis & malaria; and maternal mortality. Further attention is payed to normative objectives attached to 'global health' definitions and to paradoxes involved in attempts to define the field. Discussion The manuscript identifies denotations of 'global' as 'worldwide', as 'transcending national boundaries' and as 'holistic'. A fourth concept of 'global' as 'supraterritorial' is presented and defined as 'links between the social determinants of health anywhere in the world'. The rhetorical power of the denotations impacts considerably on the object of 'global health', exemplified in the context of malnutrition; HIV, tuberculosis & malaria; and maternal mortality. The 'global' as 'worldwide', as 'transcending national boundaries' and as 'holistic' house contradictions which can be overcome by the fourth concept of 'global' as 'supraterritorial'. The 'global-local-relationship' inherent in the proposed concept coheres with influential anthropological and sociological views despite the use of different terminology. At the same time, it may be assembled with other views on 'global' or amend apparently conflicting ones. The author argues for detaching normative objectives from 'global health' definitions to avoid so called 'entanglement-problems'. Instead, it is argued that the proposed concept constitutes an un-euphemistical approach to describe the inherently politicised field of 'global health'. Summary While global-as-worldwide and global-as-transcending-national-boundaries are misleading and produce redundancy with public and international health, global-as-supraterritorial provides 'new' objects for research, education and practice while avoiding redundancy. Linked with 'health' as a human right, this concept preserves the rhetorical power of the term 'global health' for more innovative forms of study, research and practice. The dialectic approach reveals that the contradictions involved in the different notions of the term 'global' are only of apparent nature and not exclusive, but have to be seen as complementary to each other if expected to be useful in the final step. PMID:21029401
Structural Integration of Sensors/Actuators by Laser Beam Melting for Tailored Smart Components
NASA Astrophysics Data System (ADS)
Töppel, Thomas; Lausch, Holger; Brand, Michael; Hensel, Eric; Arnold, Michael; Rotsch, Christian
2018-03-01
Laser beam melting (LBM), an additive laser powder bed fusion technology, enables the structural integration of temperature-sensitive sensors and actuators in complex monolithic metallic structures. The objective is to embed a functional component inside a metal part without losing its functionality by overheating. The first part of this paper addresses the development of a new process chain for bonded embedding of temperature-sensitive sensor/actuator systems by LBM. These systems are modularly built and coated by a multi-material/multi-layer thermal protection system of ceramic and metallic compounds. The characteristic of low global heat input in LBM is utilized for the functional embedding. In the second part, the specific functional design and optimization for tailored smart components with embedded functionalities are addressed. Numerical and experimental validated results are demonstrated on a smart femoral hip stem.
Standard formatted data units-control authority procedures
NASA Technical Reports Server (NTRS)
1991-01-01
The purpose of this document is to establish a set of minimum and optional requirements for the implementation of Control Authority (CA) organizations within and among the Agencies participating in the Consultative Committee for Space Data Systems (CCSDS). By satisfying these requirements, the resultant cooperating set of CA organizations will produce a global CA service supporting information transfer with digital data under the Standard Formatted Data Unit (SFDU) concept. This service is primarily accomplished through the registration, permanent archiving, and dissemination of metadata in the form of Metadata Objects (MDO) that assist in the interpretation of data objects received in SFDU form. This Recommendation addresses the responsibilities, services, and interface protocols for a hierarchy of CA organizations. The top level, consisting of the CCSDS Secretariat and its operational agent, is unique and primarily provides a global coordination function. The lower levels are Agency CA organizations that have primary responsibility for the registration, archiving, and dissemination of MDOs. As experience is gained and technology evolves, the CA Procedures will be extended to include enhanced services and their supporting protocols. In particular, it is anticipated that eventually CA organizations will be linked via networks on a global basis, and will provide requestors with online automated access to CA services. While this Recommendation does not preclude such operations, it also does not recommend the specific protocols to be used to ensure global compatibility of these services. These recommendations will be generated as experience is gained.
Pan, Xue; Liu, Kecheng
2017-01-01
Social influence drives human selection behaviours when numerous objects competing for limited attentions, which leads to the ‘rich get richer’ dynamics where popular objects tend to get more attentions. However, evidences have been found that, both the global information of the whole system and the local information among one’s friends have significant influence over the one’s selection. Consequently, a key question raises that, it is the local information or the global information more determinative for one’s selection? Here we compare the local-based influence and global-based influence. We show that, the selection behaviour is mainly driven by the local popularity of the objects while the global popularity plays a supplementary role driving the behaviour only when there is little local information for the user to refer to. Thereby, we propose a network model to describe the mechanism of user-object interaction evolution with social influence, where the users perform either local-driven or global-driven preferential attachments to the objects, i.e., the probability of an objects to be selected by a target user is proportional to either its local popularity or global popularity. The simulation suggests that, about 75% of the attachments should be driven by the local popularity to reproduce the empirical observations. It means that, at least in the studied context where users chose businesses on Yelp, there is a probability of 75% for a user to make a selection according to the local popularity. The proposed model and the numerical findings may shed some light on the study of social influence and evolving social systems. PMID:28406984
Pan, Xue; Hou, Lei; Liu, Kecheng
2017-01-01
Social influence drives human selection behaviours when numerous objects competing for limited attentions, which leads to the 'rich get richer' dynamics where popular objects tend to get more attentions. However, evidences have been found that, both the global information of the whole system and the local information among one's friends have significant influence over the one's selection. Consequently, a key question raises that, it is the local information or the global information more determinative for one's selection? Here we compare the local-based influence and global-based influence. We show that, the selection behaviour is mainly driven by the local popularity of the objects while the global popularity plays a supplementary role driving the behaviour only when there is little local information for the user to refer to. Thereby, we propose a network model to describe the mechanism of user-object interaction evolution with social influence, where the users perform either local-driven or global-driven preferential attachments to the objects, i.e., the probability of an objects to be selected by a target user is proportional to either its local popularity or global popularity. The simulation suggests that, about 75% of the attachments should be driven by the local popularity to reproduce the empirical observations. It means that, at least in the studied context where users chose businesses on Yelp, there is a probability of 75% for a user to make a selection according to the local popularity. The proposed model and the numerical findings may shed some light on the study of social influence and evolving social systems.
NASA Technical Reports Server (NTRS)
Vane, Deborah
1993-01-01
A discussion of the objectives of the Global Energy and Water Cycle Experiment (GEWEX) and the Continental-scale International Project (GCIP) is presented in vugraph form. The objectives of GEWEX are as follows: determine the hydrological cycle by global measurements; model the global hydrological cycle; improve observations and data assimilation; and predict response to environmental change. The objectives of GCIP are as follows: determine the time/space variability of the hydrological cycle over a continental-scale region; develop macro-scale hydrologic models that are coupled to atmospheric models; develop information retrieval schemes; and support regional climate change impact assessment.
Full waveform inversion using envelope-based global correlation norm
NASA Astrophysics Data System (ADS)
Oh, Ju-Won; Alkhalifah, Tariq
2018-05-01
To increase the feasibility of full waveform inversion on real data, we suggest a new objective function, which is defined as the global correlation of the envelopes of modelled and observed data. The envelope-based global correlation norm has the advantage of the envelope inversion that generates artificial low-frequency information, which provides the possibility to recover long-wavelength structure in an early stage. In addition, the envelope-based global correlation norm maintains the advantage of the global correlation norm, which reduces the sensitivity of the misfit to amplitude errors so that the performance of inversion on real data can be enhanced when the exact source wavelet is not available and more complex physics are ignored. Through the synthetic example for 2-D SEG/EAGE overthrust model with inaccurate source wavelet, we compare the performance of four different approaches, which are the least-squares waveform inversion, least-squares envelope inversion, global correlation norm and envelope-based global correlation norm. Finally, we apply the envelope-based global correlation norm on the 3-D Ocean Bottom Cable (OBC) data from the North Sea. The envelope-based global correlation norm captures the strong reflections from the high-velocity caprock and generates artificial low-frequency reflection energy that helps us recover long-wavelength structure of the model domain in the early stages. From this long-wavelength model, the conventional global correlation norm is sequentially applied to invert for higher-resolution features of the model.
van de Pas, Remco
2016-12-24
There has been much reflection on the need for a new understanding of global health and the urgency of a paradigm shift to address global health issues. A crucial question is whether this is still possible in current modes of global governance based on capitalist values. Four reflections are provided. (1) Ecological -centered values must become central in any future global health framework. (2) The objectives of 'sustainability' and 'economic growth' present a profound contradiction. (3) The resilience discourse maintains a gridlock in the functioning of the global health system. (4) The legitimacy of multi-stakeholder governance arrangements in global health requires urgent attention. A dual track approach is suggested. It must be aimed to transform capitalism into something better for global health while in parallel there is an urgent need to imagine a future and pathways to a different world order rooted in the principles of social justice, protecting the commons and a central role for the preservation of ecology. © 2017 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Quality of life and nutritional status among cancer patients on chemotherapy.
Vergara, Nunilon; Montoya, Jose Enrique; Luna, Herdee Gloriane; Amparo, Jose Roberto; Cristal-Luna, Gloria
2013-07-01
Malnutrition is prevalent among cancer patients, and maybe correlated with altered quality of life. The objective of this study is to determine wether quality of life among cancer patients on chemotherapy at the National Kidney and Transplant Institute- Cancer Unit differs from patients with normal nutrition based on the Subjective Global Assessment scale. A cross sectional study was conducted among cancer patients admitted for chemotherapy at the National Kidney and Transplant Institute-Cancer Unit from January to May 2011. Demographic profile, performance status by Eastern Cooperative Oncology Group performance scale, nutritional status assessment by Subjective Global Assessment, and quality of life assessment by the European Organization for Research and Treatment of Cancer QoL-30 core module were obtained. Descriptive statistics and ANOVA were performed for analysis of quality of life parameters and nutritional status. A total of 97 subjects were included in this study, 66 subjects (68.04%) were females and 31 (31.96%) were males. Mean age was 54.55 ± 11.14 years, while mean performance status by the Eastern Cooperative Oncology Group classification was 0.88 ± 0.83 with a range of 0-3. According to the Subjective Global Assessment, there were 58 patients with SGA A, classified to have adequate nutrition, and 39 patients (40.21%) were considered malnourished. Among these 39 patients, 32 were classified SGA-B (moderately malnourished) and 7 were classified SGA C (severely malnourished) mean global quality of life was 68.73 ± 19.05. Results from ANOVA test revealed that patients were statistically different across the Subjective Global Assessment groups according to global quality of life (p<0.001), physical (p<0.001), role (p<0.001), emotional (p<0.001), and cognitive functioning (p<0.001); fatigue (p<0.001), nausea and vomiting (p<0.001), pain (p<0.001), insomnia (p<0.001), and appetite loss (p<0.001). GLOBAL QUALITY OF LIFE AND ITS PARAMETERS: physical state, role, emotional state, cognitive functioning, cancer fatigue, nausea and vomiting, pain, insomnia, and loss of appetite were statistically different across all Subjective Global Assessment groups. Moreover, there was no difference between financial difficulties, social functioning, constipation and diarrhea among the Subjective Global Assessment groups.
An outer approximation method for the road network design problem
2018-01-01
Best investment in the road infrastructure or the network design is perceived as a fundamental and benchmark problem in transportation. Given a set of candidate road projects with associated costs, finding the best subset with respect to a limited budget is known as a bilevel Discrete Network Design Problem (DNDP) of NP-hard computationally complexity. We engage with the complexity with a hybrid exact-heuristic methodology based on a two-stage relaxation as follows: (i) the bilevel feature is relaxed to a single-level problem by taking the network performance function of the upper level into the user equilibrium traffic assignment problem (UE-TAP) in the lower level as a constraint. It results in a mixed-integer nonlinear programming (MINLP) problem which is then solved using the Outer Approximation (OA) algorithm (ii) we further relax the multi-commodity UE-TAP to a single-commodity MILP problem, that is, the multiple OD pairs are aggregated to a single OD pair. This methodology has two main advantages: (i) the method is proven to be highly efficient to solve the DNDP for a large-sized network of Winnipeg, Canada. The results suggest that within a limited number of iterations (as termination criterion), global optimum solutions are quickly reached in most of the cases; otherwise, good solutions (close to global optimum solutions) are found in early iterations. Comparative analysis of the networks of Gao and Sioux-Falls shows that for such a non-exact method the global optimum solutions are found in fewer iterations than those found in some analytically exact algorithms in the literature. (ii) Integration of the objective function among the constraints provides a commensurate capability to tackle the multi-objective (or multi-criteria) DNDP as well. PMID:29590111
An outer approximation method for the road network design problem.
Asadi Bagloee, Saeed; Sarvi, Majid
2018-01-01
Best investment in the road infrastructure or the network design is perceived as a fundamental and benchmark problem in transportation. Given a set of candidate road projects with associated costs, finding the best subset with respect to a limited budget is known as a bilevel Discrete Network Design Problem (DNDP) of NP-hard computationally complexity. We engage with the complexity with a hybrid exact-heuristic methodology based on a two-stage relaxation as follows: (i) the bilevel feature is relaxed to a single-level problem by taking the network performance function of the upper level into the user equilibrium traffic assignment problem (UE-TAP) in the lower level as a constraint. It results in a mixed-integer nonlinear programming (MINLP) problem which is then solved using the Outer Approximation (OA) algorithm (ii) we further relax the multi-commodity UE-TAP to a single-commodity MILP problem, that is, the multiple OD pairs are aggregated to a single OD pair. This methodology has two main advantages: (i) the method is proven to be highly efficient to solve the DNDP for a large-sized network of Winnipeg, Canada. The results suggest that within a limited number of iterations (as termination criterion), global optimum solutions are quickly reached in most of the cases; otherwise, good solutions (close to global optimum solutions) are found in early iterations. Comparative analysis of the networks of Gao and Sioux-Falls shows that for such a non-exact method the global optimum solutions are found in fewer iterations than those found in some analytically exact algorithms in the literature. (ii) Integration of the objective function among the constraints provides a commensurate capability to tackle the multi-objective (or multi-criteria) DNDP as well.
Terrestrial cross-calibrated assimilation of various datasources
NASA Astrophysics Data System (ADS)
Groß, André; Müller, Richard; Schömer, Elmar; Trentmann, Jörg
2014-05-01
We introduce a novel software tool, ANACLIM, for the efficient assimilation of multiple two-dimensional data sets using a variational approach. We consider a single objective function in two spatial coordinates with higher derivatives. This function measures the deviation of the input data from the target data set. By using the Euler-Lagrange formalism the minimization of this objective function can be transformed into a sparse system of linear equations, which can be efficiently solved by a conjugate gradient solver on a desktop workstation. The objective function allows for a series of physically-motivated constraints. The user can control the relative global weights, as well as the individual weight of each constraint on a per-grid-point level. The different constraints are realized as separate terms of the objective function: One similarity term for each input data set and two additional smoothness terms, penalizing high gradient and curvature values. ANACLIM is designed to combine similarity and smoothness operators easily and to choose different solvers. We performed a series of benchmarks to calibrate and verify our solution. We use, for example, terrestrial stations of BSRN and GEBA for the solar incoming flux and AERONET stations for aerosol optical depth. First results show that the combination of these data sources gain a significant benefit against the input datasets with our approach. ANACLIM also includes a region growing algorithm for the assimilation of ground based data. The region growing algorithm computes the maximum area around a station that represents the station data. The regions are grown under several constraints like the homogeneity of the area. The resulting dataset is then used within the assimilation process. Verification is performed by cross-validation. The method and validation results will be presented and discussed.
Physical activity, motor function, and white matter hyperintensity burden in healthy older adults
Yang, Jingyun; Arfanakis, Konstantinos; Arvanitakis, Zoe; Leurgans, Sue E.; Turner, Arlener D.; Barnes, Lisa L.; Bennett, David A.; Buchman, Aron S.
2015-01-01
Objective: To test the hypothesis that physical activity modifies the association between white matter hyperintensity (WMH) burden and motor function in healthy older persons without dementia. Methods: Total daily activity (exercise and nonexercise physical activity) was measured for up to 11 days with actigraphy (Actical; Philips Respironics, Bend, OR) in 167 older adults without dementia participating in the Rush Memory and Aging Project. Eleven motor performances were summarized into a previously described global motor score. WMH volume was expressed as percent of intracranial volume. Linear regression models, adjusted for age, education, and sex, were performed with total WMH volume as the predictor and global motor score as the outcome. Terms for total daily physical activity and its interaction with WMH volume were then added to the model. Results: Higher WMH burden was associated with lower motor function (p = 0.006), and total daily activity was positively associated with motor function (p = 0.002). Total daily activity modified the association between WMH and motor function (p = 0.007). WMH burden was not associated with motor function in persons with high activity (90th percentile). By contrast, higher WMH burden remained associated with lower motor function in persons with average (50th percentile; estimate = −0.304, slope = −0.133) and low (10th percentile; estimate = −1.793, slope = −0.241) activity. Conclusions: Higher levels of physical activity may reduce the effect of WMH burden on motor function in healthy older adults. PMID:25762710
Bilateral Theta-Burst TMS to Influence Global Gestalt Perception
Ritzinger, Bernd; Huberle, Elisabeth; Karnath, Hans-Otto
2012-01-01
While early and higher visual areas along the ventral visual pathway in the inferotemporal cortex are critical for the recognition of individual objects, the neural representation of human perception of complex global visual scenes remains under debate. Stroke patients with a selective deficit in the perception of a complex global Gestalt with intact recognition of individual objects – a deficit termed simultanagnosia – greatly helped to study this question. Interestingly, simultanagnosia typically results from bilateral lesions of the temporo-parietal junction (TPJ). The present study aimed to verify the relevance of this area for human global Gestalt perception. We applied continuous theta-burst TMS either unilaterally (left or right) or bilateral simultaneously over TPJ. Healthy subjects were presented with hierarchically organized visual stimuli that allowed parametrical degrading of the object at the global level. Identification of the global Gestalt was significantly modulated only for the bilateral TPJ stimulation condition. Our results strengthen the view that global Gestalt perception in the human brain involves TPJ and is co-dependent on both hemispheres. PMID:23110106
Bilateral theta-burst TMS to influence global gestalt perception.
Ritzinger, Bernd; Huberle, Elisabeth; Karnath, Hans-Otto
2012-01-01
While early and higher visual areas along the ventral visual pathway in the inferotemporal cortex are critical for the recognition of individual objects, the neural representation of human perception of complex global visual scenes remains under debate. Stroke patients with a selective deficit in the perception of a complex global Gestalt with intact recognition of individual objects - a deficit termed simultanagnosia - greatly helped to study this question. Interestingly, simultanagnosia typically results from bilateral lesions of the temporo-parietal junction (TPJ). The present study aimed to verify the relevance of this area for human global Gestalt perception. We applied continuous theta-burst TMS either unilaterally (left or right) or bilateral simultaneously over TPJ. Healthy subjects were presented with hierarchically organized visual stimuli that allowed parametrical degrading of the object at the global level. Identification of the global Gestalt was significantly modulated only for the bilateral TPJ stimulation condition. Our results strengthen the view that global Gestalt perception in the human brain involves TPJ and is co-dependent on both hemispheres.
Gr-GDHP: A New Architecture for Globalized Dual Heuristic Dynamic Programming.
Zhong, Xiangnan; Ni, Zhen; He, Haibo
2017-10-01
Goal representation globalized dual heuristic dynamic programming (Gr-GDHP) method is proposed in this paper. A goal neural network is integrated into the traditional GDHP method providing an internal reinforcement signal and its derivatives to help the control and learning process. From the proposed architecture, it is shown that the obtained internal reinforcement signal and its derivatives can be able to adjust themselves online over time rather than a fixed or predefined function in literature. Furthermore, the obtained derivatives can directly contribute to the objective function of the critic network, whose learning process is thus simplified. Numerical simulation studies are applied to show the performance of the proposed Gr-GDHP method and compare the results with other existing adaptive dynamic programming designs. We also investigate this method on a ball-and-beam balancing system. The statistical simulation results are presented for both the Gr-GDHP and the GDHP methods to demonstrate the improved learning and controlling performance.
Diagnosis of Swallowing Disorders: How We Interpret Pharyngeal Manometry.
Cock, Charles; Omari, Taher
2017-03-01
We provide an overview of the clinical application of novel pharyngeal high-resolution impedance manometry (HRIM) with pressure flow analysis (PFA) in our hands with example cases. In our Centre, we base our interpretation of HRIM recordings upon a qualitative assessment of pressure-impedance waveforms during individual swallows, as well as a quantitative assessment of averaged PFA swallow function variables. We provide a description of two global swallowing efficacy measures, the swallow risk index (SRI), reflecting global swallowing dysfunction (higher SRI = greater aspiration risk) and the post-swallow impedance ratio (PSIR) detecting significant post-swallow bolus residue. We describe a further eight swallow function variables specific to the hypopharynx and upper esophageal sphincter (UES), assessing hypo-pharyngeal distension pressure, contractility, bolus presence and flow timing, and UES basal tone, relaxation, opening and contractility. Pharyngeal HRIM has now come of age, being applicable for routine clinical practice to assess the biomechanics of oropharyngeal swallowing dysfunction. In the future, it may guide treatment strategies and allow more objective longitudinal follow-up on clinical outcomes.
[Visual and motor functions in schizophrenic patients].
Del Vecchio, S; Gargiulo, P A
1992-12-01
In the present work, visual and motor functions have been explored in 26 chronic schizophrenic patients, and 7 acute schizophrenic patients, compared with 26 normal controls, by means of the Bender-Gestalt Test. Parameters under consideration were: Form distortion, rotation, integration, perseveration, use of space, subtle motricity, score (global parameter), and time employed. As regards distortion and rotation there have been highly significant differences between chronic patients and control group. Among acute patients, it was observed that perseveration was also highly significant. Conversely, integration and use of space did not differ significantly among the three groups involved. The global score, resulting from all the above mentioned parameters showed important differences between both patient groups on the one hand, and control group on the other hand. Taking into account that patients were being administered neuroleptic drugs, it can safely be said, however, that the Bender-Gestalt Test allows to recognize alteration in perceptual closure consistent with a loss of the objective structure of perceived phenomena, in both chronic and acute patients.
ERIC Educational Resources Information Center
Zhuravska, Nina
2016-01-01
The article deals with analysis of challenges and objectives for higher education in the context of globalization: the forming of international labour market proves the fact that the process of international integration is affecting economy and technology as well as social and labour relations that are becoming more and more global. The…
Efficiency of extracting stereo-driven object motions
Jain, Anshul; Zaidi, Qasim
2013-01-01
Most living things and many nonliving things deform as they move, requiring observers to separate object motions from object deformations. When the object is partially occluded, the task becomes more difficult because it is not possible to use two-dimensional (2-D) contour correlations (Cohen, Jain, & Zaidi, 2010). That leaves dynamic depth matching across the unoccluded views as the main possibility. We examined the role of stereo cues in extracting motion of partially occluded and deforming three-dimensional (3-D) objects, simulated by disk-shaped random-dot stereograms set at randomly assigned depths and placed uniformly around a circle. The stereo-disparities of the disks were temporally oscillated to simulate clockwise or counterclockwise rotation of the global shape. To dynamically deform the global shape, random disparity perturbation was added to each disk's depth on each stimulus frame. At low perturbation, observers reported rotation directions consistent with the global shape, even against local motion cues, but performance deteriorated at high perturbation. Using 3-D global shape correlations, we formulated an optimal Bayesian discriminator for rotation direction. Based on rotation discrimination thresholds, human observers were 75% as efficient as the optimal model, demonstrating that global shapes derived from stereo cues facilitate inferences of object motions. To complement reports of stereo and motion integration in extrastriate cortex, our results suggest the possibilities that disparity selectivity and feature tracking are linked, or that global motion selective neurons can be driven purely from disparity cues. PMID:23325345
NASA Astrophysics Data System (ADS)
Grippa, Tais; Georganos, Stefanos; Lennert, Moritz; Vanhuysse, Sabine; Wolff, Eléonore
2017-10-01
Mapping large heterogeneous urban areas using object-based image analysis (OBIA) remains challenging, especially with respect to the segmentation process. This could be explained both by the complex arrangement of heterogeneous land-cover classes and by the high diversity of urban patterns which can be encountered throughout the scene. In this context, using a single segmentation parameter to obtain satisfying segmentation results for the whole scene can be impossible. Nonetheless, it is possible to subdivide the whole city into smaller local zones, rather homogeneous according to their urban pattern. These zones can then be used to optimize the segmentation parameter locally, instead of using the whole image or a single representative spatial subset. This paper assesses the contribution of a local approach for the optimization of segmentation parameter compared to a global approach. Ouagadougou, located in sub-Saharan Africa, is used as case studies. First, the whole scene is segmented using a single globally optimized segmentation parameter. Second, the city is subdivided into 283 local zones, homogeneous in terms of building size and building density. Each local zone is then segmented using a locally optimized segmentation parameter. Unsupervised segmentation parameter optimization (USPO), relying on an optimization function which tends to maximize both intra-object homogeneity and inter-object heterogeneity, is used to select the segmentation parameter automatically for both approaches. Finally, a land-use/land-cover classification is performed using the Random Forest (RF) classifier. The results reveal that the local approach outperforms the global one, especially by limiting confusions between buildings and their bare-soil neighbors.
NASA Astrophysics Data System (ADS)
Pasquier, B.; Holzer, M.; Frants, M.
2016-02-01
We construct a data-constrained mechanistic inverse model of the ocean's coupled phosphorus and iron cycles. The nutrient cycling is embedded in a data-assimilated steady global circulation. Biological nutrient uptake is parameterized in terms of nutrient, light, and temperature limitations on growth for two classes of phytoplankton that are not transported explicitly. A matrix formulation of the discretized nutrient tracer equations allows for efficient numerical solutions, which facilitates the objective optimization of the key biogeochemical parameters. The optimization minimizes the misfit between the modelled and observed nutrient fields of the current climate. We systematically assess the nonlinear response of the biological pump to changes in the aeolian iron supply for a variety of scenarios. Specifically, Green-function techniques are employed to quantify in detail the pathways and timescales with which those perturbations are propagated throughout the world oceans, determining the global teleconnections that mediate the response of the global ocean ecosystem. We confirm previous findings from idealized studies that increased iron fertilization decreases biological production in the subtropical gyres and we quantify the counterintuitive and asymmetric response of global productivity to increases and decreases in the aeolian iron supply.
Huberle, Elisabeth; Karnath, Hans-Otto
2006-01-01
Simultanagnosia is a rare deficit that impairs individuals in perceiving several objects at the same time. It is usually observed following bilateral parieto-occipital brain damage. Despite the restrictions in perceiving the global aspect of a scene, processing of individual objects remains unaffected. The mechanisms underlying simultanagnosia are not well understood. Previous findings indicated that the integration of multiple objects into a holistic representation of the environment is not impossible per se, but might depend on the spatial relationship between individual objects. The present study examined the influence of inter-element distances between individual objects on the recognition of global shapes in two patients with simultanagnosia. We presented Navon hierarchical letter stimuli with different inter-element distances between letters at the Local Scale. Improved recognition at the Global Scale was observed in both patients by reducing the inter-element distance. Global shape recognition in simultanagnosia thus seems to be modulated by the spatial distance of local elements and does not appear to be an all-or-nothing phenomenon depending on spatial continuity. The findings seem to argue against a deficit in visual working memory capacity as the primary deficit in simultanagnosia. However, further research is necessary to investigate alternative interpretations.
Global dynamic modeling of a transmission system
NASA Technical Reports Server (NTRS)
Choy, F. K.; Qian, W.
1993-01-01
The work performed on global dynamic simulation and noise correlation of gear transmission systems at the University of Akron is outlined. The objective is to develop a comprehensive procedure to simulate the dynamics of the gear transmission system coupled with the effects of gear box vibrations. The developed numerical model is benchmarked with results from experimental tests at NASA Lewis Research Center. The modal synthesis approach is used to develop the global transient vibration analysis procedure used in the model. Modal dynamic characteristics of the rotor-gear-bearing system are calculated by the matrix transfer method while those of the gear box are evaluated by the finite element method (NASTRAN). A three-dimensional, axial-lateral coupled bearing model is used to couple the rotor vibrations with the gear box motion. The vibrations between the individual rotor systems are coupled through the nonlinear gear mesh interactions. The global equations of motion are solved in modal coordinates and the transient vibration of the system is evaluated by a variable time-stepping integration scheme. The relationship between housing vibration and resulting noise of the gear transmission system is generated by linear transfer functions using experimental data. A nonlinear relationship of the noise components to the fundamental mesh frequency is developed using the hypercoherence function. The numerically simulated vibrations and predicted noise of the gear transmission system are compared with the experimental results from the gear noise test rig at NASA Lewis Research Center. Results of the comparison indicate that the global dynamic model developed can accurately simulate the dynamics of a gear transmission system.
Missoni, Eduardo
2013-01-01
In the context of reemerging universalistic approaches to health care, the objective of this article was to contribute to the discussion by highlighting the potential influence of global trade liberalization on the balance between health demand and the capacity of health systems pursuing universal health coverage (UHC) to supply adequate health care. Being identified as a defining feature of globalization affecting health, trade liberalization is analyzed as a complex and multidimensional influence on the implementation of UHC. The analysis adopts a systems-thinking approach and refers to the six building blocks of World Health Organization's current "framework for action," emphasizing their interconnectedness. While offering new opportunities to increase access to health information and care, in the absence of global governance mechanisms ensuring adequate health protection and promotion, global trade tends to have negative effects on health systems' capacity to ensure UHC, both by causing higher demand and by interfering with the interconnected functioning of health systems' building blocks. The prevention of such an impact and the effective implementation of UHC would highly benefit from a more consistent commitment and stronger leadership by the World Health Organization in protecting health in global policymaking fora in all sectors. Copyright © 2013 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
Cerretelli, Stefania; Poggio, Laura; Gimona, Alessandro; Yakob, Getahun; Boke, Shiferaw; Habte, Mulugeta; Coull, Malcolm; Peressotti, Alessandro; Black, Helaina
2018-07-01
Land degradation is a serious issue especially in dry and developing countries leading to ecosystem services (ESS) degradation due to soil functions' depletion. Reliably mapping land degradation spatial distribution is therefore important for policy decisions. The main objectives of this paper were to infer land degradation through ESS assessment and compare the modelling results obtained using different sets of data. We modelled important physical processes (sediment erosion and nutrient export) and the equivalent ecosystem services (sediment and nutrient retention) to infer land degradation in an area in the Ethiopian Great Rift Valley. To model soil erosion/retention capability, and nitrogen export/retention capability, two datasets were used: a 'global' dataset derived from existing global-coverage data and a hybrid dataset where global data were integrated with data from local surveys. The results showed that ESS assessments can be used to infer land degradation and identify priority areas for interventions. The comparison between the modelling results of the two different input datasets showed that caution is necessary if only global-coverage data are used at a local scale. In remote and data-poor areas, an approach that integrates global data with targeted local sampling campaigns might be a good compromise to use ecosystem services in decision-making. Copyright © 2018. Published by Elsevier B.V.
Gallo, David A; Cramer, Stefanie J; Wong, Jessica T; Bennett, David A
2012-07-01
Alzheimer's disease (AD) can impair metacognition in addition to more basic cognitive functions like memory. However, while global metacognitive inaccuracies are well documented (i.e., low deficit awareness, or anosognosia), the evidence is mixed regarding the effects of AD on local or task-based metacognitive judgments. Here we investigated local metacognition with respect to the confidence-accuracy relationship in episodic memory (i.e., metamemory). AD and control participants studied pictures of common objects and their verbal labels, and then took forced-choice picture recollection tests using the verbal labels as retrieval cues. We found that item-based confidence judgments discriminated between accurate and inaccurate recollection responses in both groups, implicating relatively spared metamemory in AD. By contrast, there was evidence for global metacognitive deficiencies, as AD participants underestimated the severity of their everyday problems compared to an informant's assessment. Within the AD group, individual differences in global metacognition were related to recollection accuracy, and global metacognition for everyday memory problems was related to task-based metacognitive accuracy. These findings suggest that AD can spare the confidence-accuracy relationship in recollection tasks, and that global and local metacognition measures tap overlapping neuropsychological processes. Copyright © 2012 Elsevier Ltd. All rights reserved.
Autefage, Hélène; Littmann, Elena; Hedegaard, Martin A. B.; Von Erlach, Thomas; O’Donnell, Matthew; Burden, Frank R.; Winkler, David A.; Stevens, Molly M.
2015-01-01
Despite the increasing sophistication of biomaterials design and functional characterization studies, little is known regarding cells’ global response to biomaterials. Here, we combined nontargeted holistic biological and physical science techniques to evaluate how simple strontium ion incorporation within the well-described biomaterial 45S5 bioactive glass (BG) influences the global response of human mesenchymal stem cells. Our objective analyses of whole gene-expression profiles, confirmed by standard molecular biology techniques, revealed that strontium-substituted BG up-regulated the isoprenoid pathway, suggesting an influence on both sterol metabolite synthesis and protein prenylation processes. This up-regulation was accompanied by increases in cellular and membrane cholesterol and lipid raft contents as determined by Raman spectroscopy mapping and total internal reflection fluorescence microscopy analyses and by an increase in cellular content of phosphorylated myosin II light chain. Our unexpected findings of this strong metabolic pathway regulation as a response to biomaterial composition highlight the benefits of discovery-driven nonreductionist approaches to gain a deeper understanding of global cell–material interactions and suggest alternative research routes for evaluating biomaterials to improve their design. PMID:25831522
Kano, Yukiko; Kono, Toshiaki; Matsuda, Natsumi; Nonaka, Maiko; Kuwabara, Hitoshi; Shimada, Takafumi; Shishikura, Kurie; Konno, Chizue; Ohta, Masataka
2015-03-30
This study investigated the relationships between tics, obsessive-compulsive symptoms (OCS), and impulsivity, and their effects on global functioning in Japanese patients with Tourette syndrome (TS), using the dimensional approach for OCS. Fifty-three TS patients were assessed using the Yale Global Tic Severity Scale, the Dimensional Yale-Brown Obsessive-Compulsive Scale, the Impulsivity Rating Scale, and the Global Assessment of Functioning Scale. Although tic severity scores were significantly and positively correlated with OCS severity scores, impulsivity severity scores were not significantly correlated with either. The global functioning score was significantly and negatively correlated with tic and OCS severity scores. Of the 6 dimensional OCS scores, only aggression scores had a significant negative correlation with global functioning scores. A stepwise multiple regression analysis showed that only OCS severity scores were significantly associated with global functioning scores. Despite a moderate correlation between tic severity and OCS severity, the impact of OCS on global functioning was greater than that of tics. Of the OCS dimensions, only aggression had a significant impact on global functioning. Our findings suggest that it is important to examine OCS using a dimensional approach when analyzing global functioning in TS patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Education and Poverty in the Global Development Agenda: Emergence, Evolution and Consolidation
ERIC Educational Resources Information Center
Tarabini, Aina
2010-01-01
The objective of this paper is to analyse the role of education and poverty in the current global development agenda. It intends to analyse the emergence, evolution and consolidation of a global agenda, which attributes a key role to education in the fight against poverty. With this objective, the paper addresses four main issues: first, it…
Object-related activity revealed by functional magnetic resonance imaging in human occipital cortex.
Malach, R; Reppas, J B; Benson, R R; Kwong, K K; Jiang, H; Kennedy, W A; Ledden, P J; Brady, T J; Rosen, B R; Tootell, R B
1995-01-01
The stages of integration leading from local feature analysis to object recognition were explored in human visual cortex by using the technique of functional magnetic resonance imaging. Here we report evidence for object-related activation. Such activation was located at the lateral-posterior aspect of the occipital lobe, just abutting the posterior aspect of the motion-sensitive area MT/V5, in a region termed the lateral occipital complex (LO). LO showed preferential activation to images of objects, compared to a wide range of texture patterns. This activation was not caused by a global difference in the Fourier spatial frequency content of objects versus texture images, since object images produced enhanced LO activation compared to textures matched in power spectra but randomized in phase. The preferential activation to objects also could not be explained by different patterns of eye movements: similar levels of activation were observed when subjects fixated on the objects and when they scanned the objects with their eyes. Additional manipulations such as spatial frequency filtering and a 4-fold change in visual size did not affect LO activation. These results suggest that the enhanced responses to objects were not a manifestation of low-level visual processing. A striking demonstration that activity in LO is uniquely correlated to object detectability was produced by the "Lincoln" illusion, in which blurring of objects digitized into large blocks paradoxically increases their recognizability. Such blurring led to significant enhancement of LO activation. Despite the preferential activation to objects, LO did not seem to be involved in the final, "semantic," stages of the recognition process. Thus, objects varying widely in their recognizability (e.g., famous faces, common objects, and unfamiliar three-dimensional abstract sculptures) activated it to a similar degree. These results are thus evidence for an intermediate link in the chain of processing stages leading to object recognition in human visual cortex. Images Fig. 1 Fig. 2 Fig. 3 PMID:7667258
Coral Reef Color: Remote and In-Situ Imaging Spectroscopy of Reef Structure and Function
NASA Astrophysics Data System (ADS)
Hochberg, E. J.
2016-02-01
Coral reefs are threatened at local to global scales by a litany of anthropogenic impacts, including overfishing, coastal development, marine and watershed pollution, rising ocean temperatures, and ocean acidification. However, available data for the primary indicator of coral reef condition — proportional cover of living coral — are surprisingly sparse and show patterns that contradict the prevailing understanding of how environment impacts reef condition. Remote sensing is the only available tool for acquiring synoptic, uniform data on reef condition at regional to global scales. Discrimination between coral and other reef benthos relies on narrow wavebands afforded by imaging spectroscopy. The same spectral information allows non-invasive quantification of photosynthetic pigment composition, which shows unexpected phenological trends. There is also potential to link biodiversity with optical diversity, though there has been no effort in that direction. Imaging spectroscopy underlies the light-use efficiency model for reef primary production by quantifying light capture, which in turn indicates biochemical capacity for CO2 assimilation. Reef calcification is strongly correlated with primary production, suggesting the possibility for an optics-based model of that aspect of reef function, as well. By scaling these spectral models for use with remote sensing, we can vastly improve our understanding of reef structure, function, and overall condition across regional to global scales. By analyzing those remote sensing products against ancillary environmental data, we can construct secondary models to predict reef futures in the era of global change. This final point is the objective of CORAL (COral Reef Airborne Laboratory), a three-year project funded under NASA's Earth Venture Suborbital-2 program to investigate the relationship between coral reef condition at the ecosystem scale and various nominal biogeophysical forcing parameters.
Coral Reef Color: Remote and In-Situ Imaging Spectroscopy of Reef Structure and Function
NASA Astrophysics Data System (ADS)
Hochberg, E. J.
2015-12-01
Coral reefs are threatened at local to global scales by a litany of anthropogenic impacts, including overfishing, coastal development, marine and watershed pollution, rising ocean temperatures, and ocean acidification. However, available data for the primary indicator of coral reef condition — proportional cover of living coral — are surprisingly sparse and show patterns that contradict the prevailing understanding of how environment impacts reef condition. Remote sensing is the only available tool for acquiring synoptic, uniform data on reef condition at regional to global scales. Discrimination between coral and other reef benthos relies on narrow wavebands afforded by imaging spectroscopy. The same spectral information allows non-invasive quantification of photosynthetic pigment composition, which shows unexpected phenological trends. There is also potential to link biodiversity with optical diversity, though there has been no effort in that direction. Imaging spectroscopy underlies the light-use efficiency model for reef primary production by quantifying light capture, which in turn indicates biochemical capacity for CO2 assimilation. Reef calcification is strongly correlated with primary production, suggesting the possibility for an optics-based model of that aspect of reef function, as well. By scaling these spectral models for use with remote sensing, we can vastly improve our understanding of reef structure, function, and overall condition across regional to global scales. By analyzing those remote sensing products against ancillary environmental data, we can construct secondary models to predict reef futures in the era of global change. This final point is the objective of CORAL (COral Reef Airborne Laboratory), a three-year project funded under NASA's Earth Venture Suborbital-2 program to investigate the relationship between coral reef condition at the ecosystem scale and various nominal biogeophysical forcing parameters.
Joint Geophysical Inversion With Multi-Objective Global Optimization Methods
NASA Astrophysics Data System (ADS)
Lelievre, P. G.; Bijani, R.; Farquharson, C. G.
2015-12-01
Pareto multi-objective global optimization (PMOGO) methods generate a suite of solutions that minimize multiple objectives (e.g. data misfits and regularization terms) in a Pareto-optimal sense. Providing a suite of models, as opposed to a single model that minimizes a weighted sum of objectives, allows a more complete assessment of the possibilities and avoids the often difficult choice of how to weight each objective. We are applying PMOGO methods to three classes of inverse problems. The first class are standard mesh-based problems where the physical property values in each cell are treated as continuous variables. The second class of problems are also mesh-based but cells can only take discrete physical property values corresponding to known or assumed rock units. In the third class we consider a fundamentally different type of inversion in which a model comprises wireframe surfaces representing contacts between rock units; the physical properties of each rock unit remain fixed while the inversion controls the position of the contact surfaces via control nodes. This third class of problem is essentially a geometry inversion, which can be used to recover the unknown geometry of a target body or to investigate the viability of a proposed Earth model. Joint inversion is greatly simplified for the latter two problem classes because no additional mathematical coupling measure is required in the objective function. PMOGO methods can solve numerically complicated problems that could not be solved with standard descent-based local minimization methods. This includes the latter two classes of problems mentioned above. There are significant increases in the computational requirements when PMOGO methods are used but these can be ameliorated using parallelization and problem dimension reduction strategies.
Improved Space Surveillance Network (SSN) Scheduling using Artificial Intelligence Techniques
NASA Astrophysics Data System (ADS)
Stottler, D.
There are close to 20,000 cataloged manmade objects in space, the large majority of which are not active, functioning satellites. These are tracked by phased array and mechanical radars and ground and space-based optical telescopes, collectively known as the Space Surveillance Network (SSN). A better SSN schedule of observations could, using exactly the same legacy sensor resources, improve space catalog accuracy through more complementary tracking, provide better responsiveness to real-time changes, better track small debris in low earth orbit (LEO) through efficient use of applicable sensors, efficiently track deep space (DS) frequent revisit objects, handle increased numbers of objects and new types of sensors, and take advantage of future improved communication and control to globally optimize the SSN schedule. We have developed a scheduling algorithm that takes as input the space catalog and the associated covariance matrices and produces a globally optimized schedule for each sensor site as to what objects to observe and when. This algorithm is able to schedule more observations with the same sensor resources and have those observations be more complementary, in terms of the precision with which each orbit metric is known, to produce a satellite observation schedule that, when executed, minimizes the covariances across the entire space object catalog. If used operationally, the results would be significantly increased accuracy of the space catalog with fewer lost objects with the same set of sensor resources. This approach inherently can also trade-off fewer high priority tasks against more lower-priority tasks, when there is benefit in doing so. Currently the project has completed a prototyping and feasibility study, using open source data on the SSN's sensors, that showed significant reduction in orbit metric covariances. The algorithm techniques and results will be discussed along with future directions for the research.
An Evaluation of the Sniffer Global Optimization Algorithm Using Standard Test Functions
NASA Astrophysics Data System (ADS)
Butler, Roger A. R.; Slaminka, Edward E.
1992-03-01
The performance of Sniffer—a new global optimization algorithm—is compared with that of Simulated Annealing. Using the number of function evaluations as a measure of efficiency, the new algorithm is shown to be significantly better at finding the global minimum of seven standard test functions. Several of the test functions used have many local minima and very steep walls surrounding the global minimum. Such functions are intended to thwart global minimization algorithms.
Mcalister, Courtney; Schmitter-Edgecombe, Maureen; Lamb, Richard
2016-01-01
The objective of this meta-analysis was to improve understanding of the heterogeneity in the relationship between cognition and functional status in individuals with mild cognitive impairment (MCI). Demographic, clinical, and methodological moderators were examined. Cognition explained an average of 23% of the variance in functional outcomes. Executive function measures explained the largest amount of variance (37%), whereas global cognitive status and processing speed measures explained the least (20%). Short- and long-delayed memory measures accounted for more variance (35% and 31%) than immediate memory measures (18%), and the relationship between cognition and functional outcomes was stronger when assessed with informant-report (28%) compared with self-report (21%). Demographics, sample characteristics, and type of everyday functioning measures (i.e., questionnaire, performance-based) explained relatively little variance compared with cognition. Executive functioning, particularly measured by Trails B, was a strong predictor of everyday functioning in individuals with MCI. A large proportion of variance remained unexplained by cognition. PMID:26743326
Quality of Life among Breast Cancer Patients In Malaysia.
Ganesh, Sri; Lye, Munn-Sann; Lau, Fen Nee
2016-01-01
Among the factors reported to determine the quality of life of breast cancer patients are socio- demographic background, clinical stage, type of treatment received, and the duration since diagnosis. The objective of this study was to determine the quality of life (QOL) scores among breast cancer patients at a Malaysian public hospital. This cross-sectional study of breast cancer patients was conducted between March to June 2013. QOL scores were determined using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and its breast cancer supplementary measure (QLQ-BR23). Both the QLQ-C30 and QLQ-BR23 assess items from functional and symptom scales. The QLQ-C30 in addition also measures the Global Health Status (GHS). Systematic random sampling was used to recruit patients. 223 breast cancer patients were recruited with a response rate of 92.1%. The mean age of the patients was 52.4 years (95% CI = 51.0, 53.7, SD=10.3). Majority of respondents are Malays (60.5%), followed by Chinese (19.3%), Indians (18.4%), and others (1.8%). More than 50% of respondents are at stage III and stage IV of malignancy. The mean Global Health Status was 65.7 (SD = 21.4). From the QLQ-C30, the mean score in the functioning scale was highest for 'cognitive functioning' (84.1, SD=18.0), while the mean score in the symptom scale was highest for 'financial difficulties' (40.1, SD=31.6). From the QLQ-BR23, the mean score for functioning scale was highest for 'body image' (80.0, SD=24.6) while the mean score in the symptom scale was highest for 'upset by hair loss' (36.2, SD=29.4). Two significant predictors for Global Health Status were age and employment. The predictors explained 10.6% of the variation of global health status (R2=0.106). Age and employment were found to be significant predictors for Global Health Status (GHS). The Quality of Life among breast cancer patients reflected by the GHS improves as age and employment increases.
Ménard, Richard; Deshaies-Jacques, Martin; Gasset, Nicolas
2016-09-01
An objective analysis is one of the main components of data assimilation. By combining observations with the output of a predictive model we combine the best features of each source of information: the complete spatial and temporal coverage provided by models, with a close representation of the truth provided by observations. The process of combining observations with a model output is called an analysis. To produce an analysis requires the knowledge of observation and model errors, as well as its spatial correlation. This paper is devoted to the development of methods of estimation of these error variances and the characteristic length-scale of the model error correlation for its operational use in the Canadian objective analysis system. We first argue in favor of using compact support correlation functions, and then introduce three estimation methods: the Hollingsworth-Lönnberg (HL) method in local and global form, the maximum likelihood method (ML), and the [Formula: see text] diagnostic method. We perform one-dimensional (1D) simulation studies where the error variance and true correlation length are known, and perform an estimation of both error variances and correlation length where both are non-uniform. We show that a local version of the HL method can capture accurately the error variances and correlation length at each observation site, provided that spatial variability is not too strong. However, the operational objective analysis requires only a single and globally valid correlation length. We examine whether any statistics of the local HL correlation lengths could be a useful estimate, or whether other global estimation methods such as by the global HL, ML, or [Formula: see text] should be used. We found in both 1D simulation and using real data that the ML method is able to capture physically significant aspects of the correlation length, while most other estimates give unphysical and larger length-scale values. This paper describes a proposed improvement of the objective analysis of surface pollutants at Environment and Climate Change Canada (formerly known as Environment Canada). Objective analyses are essentially surface maps of air pollutants that are obtained by combining observations with an air quality model output, and are thought to provide a complete and more accurate representation of the air quality. The highlight of this study is an analysis of methods to estimate the model (or background) error correlation length-scale. The error statistics are an important and critical component to the analysis scheme.
Convergence of Proximal Iteratively Reweighted Nuclear Norm Algorithm for Image Processing.
Sun, Tao; Jiang, Hao; Cheng, Lizhi
2017-08-25
The nonsmooth and nonconvex regularization has many applications in imaging science and machine learning research due to its excellent recovery performance. A proximal iteratively reweighted nuclear norm algorithm has been proposed for the nonsmooth and nonconvex matrix minimizations. In this paper, we aim to investigate the convergence of the algorithm. With the Kurdyka-Łojasiewicz property, we prove the algorithm globally converges to a critical point of the objective function. The numerical results presented in this paper coincide with our theoretical findings.
Effects of Meditation on Symptoms of Knee Osteoarthritis
Selfe, Terry Kit; Innes, Kim E.
2014-01-01
Objective The aim of this study was to investigate changes in knee pain, function, and related indices in older adults with osteoarthritis (OA) of the knee, following an 8-week meditation program. Methods Eleven community-dwelling adults with physician- confirmed knee OA were enrolled in the study. Core outcomes included recommended measures of knee pain (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] and 11-point numeric rating scale [NRS]), function (WOMAC), and perceived global status (patient global assessment). Additional outcomes included: perceived stress; stress hardiness; mood; sleep; and sympathetic activation. Following baseline assessment, participants were trained briefly in mantra meditation and instructed to meditate for 15–20 minutes twice daily for 8 weeks, and to record each practice session on a daily log. Changes over time were analyzed using paired t-tests. Results Nine participants (82%) completed the study. Participants had statistically significant improvements in all core outcomes: knee pain (WOMAC: 47.7% ± 25.1% reduction, P = 0.001; NRS: 42.6% ± 34.6% reduction, P < 0.01); function (44.8% ± 29.9, P = 0.001); and global status (45.7% ± 36.5, P = 0.01); as well as knee stiffness (P = 0.005), mood (P = 0.05), and a WOMAC proxy for sleep disturbance (P = 0.005). Conclusions Findings from this pilot study suggest that a mantra meditation program may help reduce knee pain and dysfunction, as well as improving mood and related outcomes in adults with knee OA. PMID:26549967
Using Java to generate globally unique identifiers for DICOM objects.
Kamauu, Aaron W C; Duvall, Scott L; Avrin, David E
2009-03-01
Digital imaging and communication in medicine (DICOM) specifies that all DICOM objects have globally unique identifiers (UIDs). Creating these UIDs can be a difficult task due to the variety of techniques in use and the requirement to ensure global uniqueness. We present a simple technique of combining a root organization identifier, assigned descriptive identifiers, and JAVA generated unique identifiers to construct DICOM compliant UIDs.
Berg, Kelly C.; Crosby, Ross D.; Cao, Li; Crow, Scott J.; Engel, Scott G.; Wonderlich, Stephen A.; Peterson, Carol B.
2015-01-01
Objective The objective was to examine the trajectory of five types of negative affect (global negative affect, fear, guilt, hostility, sadness) prior to and following three types of eating episodes (overeating in the absence of loss of control [OE-only], loss of control eating in the absence of overeating [LOC-only], and binge eating) among obese adults using ecological momentary assessment (EMA). Method Fifty obese adults (84% female) completed a two-week EMA protocol during which they were asked to record all eating episodes and rate each episode on continua of overeating and loss of control. Momentary measures of global negative affect, fear, guilt, hostility, and sadness were assessed using an abbreviated version of the Positive and Negative Affect Schedule (PANAS). Trajectories for each of the five types of negative affect were modeled prior to and following episodes of OE-only, LOC-only, and binge eating. Results Consistent with previous findings, global negative affect and Guilt increased prior to and decreased following binge eating episodes (all ps<.05). Guilt also decreased following OE-only episodes (p<.05). Discussion These results are consistent with the affect regulation model of binge eating and suggest that binge eating may function to regulate global negative affect, and more specifically, guilt among obese adults. These data suggest that the relationship between negative affect and binge eating may not be unique to individuals with clinical eating disorders and indicate that targeting negative affect may be an effective strategy for the treatment of binge eating in the context of obesity. PMID:25808854
Eby, Chas
2014-01-01
The Global Health Security Agenda's objectives contain components that could help health departments address emerging public health challenges that threaten the population. As part of the agenda, partner countries with advanced public health systems will support the development of infrastructure in stakeholder health departments. To facilitate this process and augment local programs, state and local health departments may want to include concepts of health security in their public health preparedness offices in order to simultaneously build capacity. Health security programs developed by public health departments should complete projects that are closely aligned with the objectives outlined in the global agenda and that facilitate the completion of current preparedness grant requirements. This article identifies objectives and proposes tactical local projects that run parallel to the 9 primary objectives of the Global Health Security Agenda. Executing concurrent projects at the international and local levels in preparedness offices will accelerate the completion of these objectives and help prevent disease epidemics, detect health threats, and respond to public health emergencies. Additionally, future funding tied or related to health security may become more accessible to state and local health departments that have achieved these objectives.
Li, Xiangrong; Zhao, Xupei; Duan, Xiabin; Wang, Xiaoliang
2015-01-01
It is generally acknowledged that the conjugate gradient (CG) method achieves global convergence—with at most a linear convergence rate—because CG formulas are generated by linear approximations of the objective functions. The quadratically convergent results are very limited. We introduce a new PRP method in which the restart strategy is also used. Moreover, the method we developed includes not only n-step quadratic convergence but also both the function value information and gradient value information. In this paper, we will show that the new PRP method (with either the Armijo line search or the Wolfe line search) is both linearly and quadratically convergent. The numerical experiments demonstrate that the new PRP algorithm is competitive with the normal CG method. PMID:26381742
Li, Xiangrong; Zhao, Xupei; Duan, Xiabin; Wang, Xiaoliang
2015-01-01
It is generally acknowledged that the conjugate gradient (CG) method achieves global convergence--with at most a linear convergence rate--because CG formulas are generated by linear approximations of the objective functions. The quadratically convergent results are very limited. We introduce a new PRP method in which the restart strategy is also used. Moreover, the method we developed includes not only n-step quadratic convergence but also both the function value information and gradient value information. In this paper, we will show that the new PRP method (with either the Armijo line search or the Wolfe line search) is both linearly and quadratically convergent. The numerical experiments demonstrate that the new PRP algorithm is competitive with the normal CG method.
NASA Astrophysics Data System (ADS)
Xu, Shuo; Ji, Ze; Truong Pham, Duc; Yu, Fan
2011-11-01
The simultaneous mission assignment and home allocation for hospital service robots studied is a Multidimensional Assignment Problem (MAP) with multiobjectives and multiconstraints. A population-based metaheuristic, the Binary Bees Algorithm (BBA), is proposed to optimize this NP-hard problem. Inspired by the foraging mechanism of honeybees, the BBA's most important feature is an explicit functional partitioning between global search and local search for exploration and exploitation, respectively. Its key parts consist of adaptive global search, three-step elitism selection (constraint handling, non-dominated solutions selection, and diversity preservation), and elites-centred local search within a Hamming neighbourhood. Two comparative experiments were conducted to investigate its single objective optimization, optimization effectiveness (indexed by the S-metric and C-metric) and optimization efficiency (indexed by computational burden and CPU time) in detail. The BBA outperformed its competitors in almost all the quantitative indices. Hence, the above overall scheme, and particularly the searching history-adapted global search strategy was validated.
Multilevel algorithms for nonlinear optimization
NASA Technical Reports Server (NTRS)
Alexandrov, Natalia; Dennis, J. E., Jr.
1994-01-01
Multidisciplinary design optimization (MDO) gives rise to nonlinear optimization problems characterized by a large number of constraints that naturally occur in blocks. We propose a class of multilevel optimization methods motivated by the structure and number of constraints and by the expense of the derivative computations for MDO. The algorithms are an extension to the nonlinear programming problem of the successful class of local Brown-Brent algorithms for nonlinear equations. Our extensions allow the user to partition constraints into arbitrary blocks to fit the application, and they separately process each block and the objective function, restricted to certain subspaces. The methods use trust regions as a globalization strategy, and they have been shown to be globally convergent under reasonable assumptions. The multilevel algorithms can be applied to all classes of MDO formulations. Multilevel algorithms for solving nonlinear systems of equations are a special case of the multilevel optimization methods. In this case, they can be viewed as a trust-region globalization of the Brown-Brent class.
Fuller, Catherine J; Bladon, Bruce M; Driver, Adam J; Barr, Alistair R S
2006-03-01
The objective of this study was to assess the reliability of lameness scoring in horses. One veterinary surgeon examined nineteen lame horses on four occasions. Gait was recorded by camcorder, and scored from 0 to 10 ranging from sound to non-weight bearing lameness. A global score of overall change in lameness during the study was also determined for each horse. To measure intra-assessor reliability of the scoring systems, one veterinary surgeon scored videotapes of the horses' gaits on two occasions. To measure inter-assessor reliability, three veterinary surgeons viewed the videotapes, assigning individual lameness scores plus global scores to each horse. Reliability of individual lameness scoring was good intra-assessor, but only just within our acceptable limit inter-assessor. However, global scoring of change in lameness throughout the study was found to be reliable overall. Since clinician scoring is commonly used to assess lameness in horses, this is an important finding, fundamental to future clinical studies.
Calabrò, Rocco Salvatore; Naro, Antonino; Russo, Margherita; Leo, Antonino; Balletta, Tina; Saccá, Ileana; De Luca, Rosaria; Bramanti, Placido
2015-01-01
Abstract Background: Tilt-table equipped with the dynamic foot-support (ERIGO) and the functional electric stimulation could be a safe and suitable device for stabilization of vital signs, increasing patient’s motivation for further recovery, decreasing the duration of hospitalization, and accelerating the adaptation to vertical posture in bedridden patients with brain-injury. Moreover, it is conceivable that verticalization may improve cognitive functions, and induce plastic changes at sensory motor and vestibular system level that may in turn facilitate motor functional recovery. Objective: To test the safety and effectiveness of ERIGO treatment on motor and cognitive functions, cortical plasticity within vestibular and sensory-motor systems in a bedridden post-stroke sample. Methods: 20 patients were randomly divided in two groups that performed ERIGO training (30 sessions) (G1) or physiotherapist-assisted verticalization training (same duration) (G2), beyond conventional neurorehabilitation treatment. Motor and cognitive functions as well as sensory-motor and vestibular system plasticity were investigated either before (T0) or after (T1) the rehabilitative protocols. Results: Both the verticalization treatments were well-tolerated. Notably, the G1 patients had a significant improvement in cognitive function (p = 0.03), global motor function (p = 0.006), sensory-motor (p < 0.001) and vestibular system plasticity (p = 0.02) as compared to G2. Conclusions: ERIGO training could be a valuable tool for the adaptation to the vertical position with a better global function improvement, as also suggested by the sensory-motor and vestibular system plasticity induction. PMID:26410207
DeFife, Jared A; Goldberg, Melissa; Westen, Drew
2015-04-01
Central to the proposed DSM-5 general definition of personality disorder (PD) are features of self- and interpersonal functioning. The Social Cognition and Object Relations Scale-Global Rating Method (SCORS-G) is a coding system that assesses eight dimensions of self- and relational experience that can be applied to narrative data or used by clinically experienced observers to quantify observations of patients in ongoing psychotherapy. This study aims to evaluate the relationship of SCORS-G dimensions to personality pathology in adolescents and their incremental validity for predicting multiple domains of adaptive functioning. A total of 294 randomly sampled doctoral-level clinical psychologists and psychiatrists described an adolescent patient in their care based on all available data. Individual SCORS-G variables demonstrated medium-to-large effect size differences for PD versus non-PD identified adolescents (d = .49-1.05). A summary SCORS-Composite rating was significantly related to composite measurements of global adaptive functioning (r = .66), school functioning (r = .47), externalizing behavior (r = -.49), and prior psychiatric history (r = -.31). The SCORS-Composite significantly predicted variance in domains of adaptive functioning above and beyond age and DSM-IV PD diagnosis (ΔR(2)s = .07-.32). As applied to adolescents, the SCORS-G offers a framework for a clinically meaningful and empirically sound dimensional assessment of self- and other representations and interpersonal functioning capacities. Our findings support the inclusion of self- and interpersonal capacities in the DSM-5 general definition of personality disorder as an improvement to existing PD diagnosis for capturing varied domains of adaptive functioning and psychopathology.
A Study of Penalty Function Methods for Constraint Handling with Genetic Algorithm
NASA Technical Reports Server (NTRS)
Ortiz, Francisco
2004-01-01
COMETBOARDS (Comparative Evaluation Testbed of Optimization and Analysis Routines for Design of Structures) is a design optimization test bed that can evaluate the performance of several different optimization algorithms. A few of these optimization algorithms are the sequence of unconstrained minimization techniques (SUMT), sequential linear programming (SLP) and the sequential quadratic programming techniques (SQP). A genetic algorithm (GA) is a search technique that is based on the principles of natural selection or "survival of the fittest". Instead of using gradient information, the GA uses the objective function directly in the search. The GA searches the solution space by maintaining a population of potential solutions. Then, using evolving operations such as recombination, mutation and selection, the GA creates successive generations of solutions that will evolve and take on the positive characteristics of their parents and thus gradually approach optimal or near-optimal solutions. By using the objective function directly in the search, genetic algorithms can be effectively applied in non-convex, highly nonlinear, complex problems. The genetic algorithm is not guaranteed to find the global optimum, but it is less likely to get trapped at a local optimum than traditional gradient-based search methods when the objective function is not smooth and generally well behaved. The purpose of this research is to assist in the integration of genetic algorithm (GA) into COMETBOARDS. COMETBOARDS cast the design of structures as a constrained nonlinear optimization problem. One method used to solve constrained optimization problem with a GA to convert the constrained optimization problem into an unconstrained optimization problem by developing a penalty function that penalizes infeasible solutions. There have been several suggested penalty function in the literature each with there own strengths and weaknesses. A statistical analysis of some suggested penalty functions is performed in this study. Also, a response surface approach to robust design is used to develop a new penalty function approach. This new penalty function approach is then compared with the other existing penalty functions.
Hollocks, Matthew J.; Morris, Robin G.; Markus, Hugh S.
2017-01-01
Objective To determine the prevalence of apathy and depression in cerebral small vessel disease (SVD), and the relationships between both apathy and depression with cognition. To examine whether apathy is specifically related to impairment in executive functioning and processing speed. Methods 196 patients with a clinical lacunar stroke and an anatomically corresponding lacunar infarct on MRI were compared to 300 stroke-free controls. Apathy and depression were measured using the Geriatric Depression Scale, and cognitive functioning was assessed using an SVD cognitive screening tool, the Brief Memory and Executive Test, which measures executive functioning/processing speed and memory/orientation. Path analysis and binary logistic regression were used to assess the relation between apathy, depression and cognitive impairment. Results 31 participants with SVD (15.8%) met criteria for apathy only, 23 (11.8%) for both apathy and depression, and 2 (1.0%) for depression only. In the SVD group the presence of apathy was related to global cognition, and specifically to impaired executive functioning/processing speed, but not memory/orientation. The presence of depression was not related to global cognition, impaired executive functioning/processing speed or memory/orientation. Conclusions Apathy is a common feature of SVD and is associated with impaired executive functioning/processing speed suggesting the two may share biological mechanisms. Screening for apathy should be considered in SVD, and further work is required to develop and evaluate effective apathy treatment or management in SVD. PMID:28493898
The Effects of Poor Sleep Quality on Cognitive Function of Patients with Cirrhosis
Stewart, Charmaine A.; Auger, Robert; Enders, Felicity T. B.; Felmlee-Devine, Donna; Smith, Glenn E.
2014-01-01
Objectives: This study was conducted to assess the ill-defined relationship between sleep quality and multiple, specific domains of cognitive function in patients with cirrhosis. Methods: A comprehensive battery of neuropsychological tests (divided into six neurocognitive domains) and a standardized, validated measure of sleep quality (Pittsburgh Sleep Quality Index [PSQI]) were administered to patients with cirrhosis and without evidence of overt hepatic encephalopathy, recruited from liver transplant and advanced liver disease clinics (n = 34). An inflammatory bowel disease (IBD) control group (n = 23) was similarly recruited and evaluated to control for the secondary effect of a chronic illness on cognition. PSQI global and component scores were used to predict cognitive function in each neurocognitive domain, using linear regression Results: Global PSQI scores were significantly higher (indicating poorer sleep quality) in the cirrhosis group (median [range] = 10 [1-19]) than in IBD controls = 5 (1-14); p = 0.002). After controlling for age and education, short duration of sleep was associated with impaired memory for patients with cirrhosis; the use of soporific agents was associated with poor visual-perceptual function in patients with IBD. Conclusions: Poor sleep was associated with worsening of the already impaired cognitive function of patients with cirrhosis. Citation: Stewart CA; Auger R; Enders FTB; Felmlee-Devine D; Smith GE. The effects of poor sleep quality on cognitive function of patients with cirrhosis. J Clin Sleep Med 2014;10(1):21-26. PMID:24426816
NASA Astrophysics Data System (ADS)
Ueda, Haruka; Dazai, Ryota; Kaseda, Chosei; Ikaga, Toshiharu; Kato, Akihiro
Demand among large office buildings for the energy-saving benefits of the HVAC (Heating, Ventilating and Air-Conditioning) System are increasing as more and more people become concerned with global environmental issues. However, immoderate measures taken in the interest of energy conservation may encroach on the thermal comfort and productivity level of office workers. Building management should satisfy both indoor thermal comfort and energy conservation while adapting to the many regulatory, social, climate, and other changes that occur during the lifespan of the building. This paper demonstrates how optimal control of the HVAC system, based on data modeling and the multi-objective optimal method, achieves an efficient equilibrium between thermal comfort and energy conservation.
Objective Data Assessment (ODA) Methods as Nutritional Assessment Tools.
Hamada, Yasuhiro
2015-01-01
Nutritional screening and assessment should be a standard of care for all patients because nutritional management plays an important role in clinical practice. However, there is no gold standard for the diagnosis of malnutrition or undernutrition, although a large number of nutritional screening and assessment tools have been developed. Nutritional screening and assessment tools are classified into two categories, namely, subjective global assessment (SGA) and objective data assessment (ODA). SGA assesses nutritional status based on the features of medical history and physical examination. On the other hand, ODA consists of objective data provided from various analyses, such as anthropometry, bioimpedance analysis (BIA), dual-energy X-ray absorptiometry (DEXA), computed tomography (CT), magnetic resonance imaging (MRI), laboratory tests, and functional tests. This review highlights knowledge on the performance of ODA methods for the assessment of nutritional status in clinical practice. J. Med. Invest. 62: 119-122, August, 2015.
Ptak, Radek; Lazeyras, François; Di Pietro, Marie; Schnider, Armin; Simon, Stéphane R
2014-07-01
Patients with visual object agnosia fail to recognize the identity of visually presented objects despite preserved semantic knowledge. Object agnosia may result from damage to visual cortex lying close to or overlapping with the lateral occipital complex (LOC), a brain region that exhibits selectivity to the shape of visually presented objects. Despite this anatomical overlap the relationship between shape processing in the LOC and shape representations in object agnosia is unknown. We studied a patient with object agnosia following isolated damage to the left occipito-temporal cortex overlapping with the LOC. The patient showed intact processing of object structure, yet often made identification errors that were mainly based on the global visual similarity between objects. Using functional Magnetic Resonance Imaging (fMRI) we found that the damaged as well as the contralateral, structurally intact right LOC failed to show any object-selective fMRI activity, though the latter retained selectivity for faces. Thus, unilateral damage to the left LOC led to a bilateral breakdown of neural responses to a specific stimulus class (objects and artefacts) while preserving the response to a different stimulus class (faces). These findings indicate that representations of structure necessary for the identification of objects crucially rely on bilateral, distributed coding of shape features. Copyright © 2014 Elsevier Ltd. All rights reserved.
Genetic algorithms for the application of Activated Sludge Model No. 1.
Kim, S; Lee, H; Kim, J; Kim, C; Ko, J; Woo, H; Kim, S
2002-01-01
The genetic algorithm (GA) has been integrated into the IWA ASM No. 1 to calibrate important stoichiometric and kinetic parameters. The evolutionary feature of GA was used to configure the multiple local optima as well as the global optimum. The objective function of optimization was designed to minimize the difference between estimated and measured effluent concentrations at the activated sludge system. Both steady state and dynamic data of the simulation benchmark were used for calibration using denitrification layout. Depending upon the confidence intervals and objective functions, the proposed method provided distributions of parameter space. Field data have been collected and applied to validate calibration capacity of GA. Dynamic calibration was suggested to capture periodic variations of inflow concentrations. Also, in order to verify this proposed method in real wastewater treatment plant, measured data sets for substrate concentrations were obtained from Haeundae wastewater treatment plant and used to estimate parameters in the dynamic system. The simulation results with calibrated parameters matched well with the observed concentrations of effluent COD.
Use of subjective and objective criteria to categorise visual disability.
Kajla, Garima; Rohatgi, Jolly; Dhaliwal, Upreet
2014-04-01
Visual disability is categorised using objective criteria. Subjective measures are not considered. To use subjective criteria along with objective ones to categorise visual disability. Ophthalmology out-patient department; teaching hospital; observational study. Consecutive persons aged >25 years, with vision <20/20 (in one or both eyes) due to chronic conditions, like cataract and refractive errors, were categorized into 11 groups of increasing disability; group-zero: normal range of vision, to group-X: no perception of light, bilaterally. Snellen's vision; binocular contrast sensitivity (Pelli-Robson chart); automated binocular visual field (Humphrey; Esterman test); and vision-related quality of life (Indian Visual Function Questionnaire-33; IND-VFQ33) were recorded. SPSS version-17; Kruskal-wallis test was used to compare contrast sensitivity and visual fields across groups, and Mann-Whitney U test for pair-wise comparison (Bonferroni adjustment; P < 0.01). One-way ANOVA compared quality of life data across groups; for pairwise significance, Dunnett T3 test was applied. In 226 patients, contrast sensitivity and visual fields were comparable for differing disability grades except when disability was severe (P < 0.001), or moderately severe (P < 0.01). Individual scales of IND-VFQ33 were also mostly comparable; however, global scores showed a distinct pattern, being different for some disability grades but comparable for groups III (78.51 ± 6.86) and IV (82.64 ± 5.80), and groups IV and V (77.23 ± 3.22); these were merged to generate group 345; similarly, global scores were comparable for adjacent groups V and VI (72.53 ± 6.77), VI and VII (74.46 ± 4.32), and VII and VIII (69.12 ± 5.97); these were merged to generate group 5678; thereafter, contrast sensitivity and global and individual IND-VFQ33 scores could differentiate between different grades of disability in the five new groups. Subjective criteria made it possible to objectively reclassify visual disability. Visual disability grades could be redefined to accommodate all from zero-100%.
The role of temporo-parietal junction (TPJ) in global Gestalt perception.
Huberle, Elisabeth; Karnath, Hans-Otto
2012-07-01
Grouping processes enable the coherent perception of our environment. A number of brain areas has been suggested to be involved in the integration of elements into objects including early and higher visual areas along the ventral visual pathway as well as motion-processing areas of the dorsal visual pathway. However, integration not only is required for the cortical representation of individual objects, but is also essential for the perception of more complex visual scenes consisting of several different objects and/or shapes. The present fMRI experiments aimed to address such integration processes. We investigated the neural correlates underlying the global Gestalt perception of hierarchically organized stimuli that allowed parametrical degrading of the object at the global level. The comparison of intact versus disturbed perception of the global Gestalt revealed a network of cortical areas including the temporo-parietal junction (TPJ), anterior cingulate cortex and the precuneus. The TPJ location corresponds well with the areas known to be typically lesioned in stroke patients with simultanagnosia following bilateral brain damage. These patients typically show a deficit in identifying the global Gestalt of a visual scene. Further, we found the closest relation between behavioral performance and fMRI activation for the TPJ. Our data thus argue for a significant role of the TPJ in human global Gestalt perception.
Mehri, Mehran
2014-07-01
The optimization algorithm of a model may have significant effects on the final optimal values of nutrient requirements in poultry enterprises. In poultry nutrition, the optimal values of dietary essential nutrients are very important for feed formulation to optimize profit through minimizing feed cost and maximizing bird performance. This study was conducted to introduce a novel multi-objective algorithm, desirability function, for optimization the bird response models based on response surface methodology (RSM) and artificial neural network (ANN). The growth databases on the central composite design (CCD) were used to construct the RSM and ANN models and optimal values for 3 essential amino acids including lysine, methionine, and threonine in broiler chicks have been reevaluated using the desirable function in both analytical approaches from 3 to 16 d of age. Multi-objective optimization results showed that the most desirable function was obtained for ANN-based model (D = 0.99) where the optimal levels of digestible lysine (dLys), digestible methionine (dMet), and digestible threonine (dThr) for maximum desirability were 13.2, 5.0, and 8.3 g/kg of diet, respectively. However, the optimal levels of dLys, dMet, and dThr in the RSM-based model were estimated at 11.2, 5.4, and 7.6 g/kg of diet, respectively. This research documented that the application of ANN in the broiler chicken model along with a multi-objective optimization algorithm such as desirability function could be a useful tool for optimization of dietary amino acids in fractional factorial experiments, in which the use of the global desirability function may be able to overcome the underestimations of dietary amino acids resulting from the RSM model. © 2014 Poultry Science Association Inc.
Integrated aerodynamic/dynamic optimization of helicopter rotor blades
NASA Technical Reports Server (NTRS)
Chattopadhyay, Aditi; Walsh, Joanne L.; Riley, Michael F.
1989-01-01
An integrated aerodynamic/dynamic optimization procedure is used to minimize blade weight and 4 per rev vertical hub shear for a rotor blade in forward flight. The coupling of aerodynamics and dynamics is accomplished through the inclusion of airloads which vary with the design variables during the optimization process. Both single and multiple objective functions are used in the optimization formulation. The Global Criteria Approach is used to formulate the multiple objective optimization and results are compared with those obtained by using single objective function formulations. Constraints are imposed on natural frequencies, autorotational inertia, and centrifugal stress. The program CAMRAD is used for the blade aerodynamic and dynamic analyses, and the program CONMIN is used for the optimization. Since the spanwise and the azimuthal variations of loading are responsible for most rotor vibration and noise, the vertical airload distributions on the blade, before and after optimization, are compared. The total power required by the rotor to produce the same amount of thrust for a given area is also calculated before and after optimization. Results indicate that integrated optimization can significantly reduce the blade weight, the hub shear and the amplitude of the vertical airload distributions on the blade and the total power required by the rotor.
Neuronal Reward and Decision Signals: From Theories to Data
Schultz, Wolfram
2015-01-01
Rewards are crucial objects that induce learning, approach behavior, choices, and emotions. Whereas emotions are difficult to investigate in animals, the learning function is mediated by neuronal reward prediction error signals which implement basic constructs of reinforcement learning theory. These signals are found in dopamine neurons, which emit a global reward signal to striatum and frontal cortex, and in specific neurons in striatum, amygdala, and frontal cortex projecting to select neuronal populations. The approach and choice functions involve subjective value, which is objectively assessed by behavioral choices eliciting internal, subjective reward preferences. Utility is the formal mathematical characterization of subjective value and a prime decision variable in economic choice theory. It is coded as utility prediction error by phasic dopamine responses. Utility can incorporate various influences, including risk, delay, effort, and social interaction. Appropriate for formal decision mechanisms, rewards are coded as object value, action value, difference value, and chosen value by specific neurons. Although all reward, reinforcement, and decision variables are theoretical constructs, their neuronal signals constitute measurable physical implementations and as such confirm the validity of these concepts. The neuronal reward signals provide guidance for behavior while constraining the free will to act. PMID:26109341
Implementation of the Global Parameters Determination in Gaia's Astrometric Solution (AGIS)
NASA Astrophysics Data System (ADS)
Raison, F.; Olias, A.; Hobbs, D.; Lindegren, L.
2010-12-01
Gaia is ESA’s space astrometry mission with a foreseen launch date in early 2012. Its main objective is to perform a stellar census of the 1000 Million brightest objects in our galaxy (completeness to V=20 mag) from which an astrometric catalog of micro-arcsec level accuracy will be constructed. A key element in this endeavor is the Astrometric Global Iterative Solution (AGIS). A core part of AGIS is to determine the accurate spacecraft attitude, geometric instrument calibration and astrometric model parameters for a well-behaved subset of all the objects (the ‘primary stars’). In addition, a small number of global parameters will be estimated, one of these being PPN γ. We present here the implementation of the algorithms dedicated to the determination of the global parameters.
Killaspy, Helen; Barnes, Thomas R E; Barrett, Barbara; Byford, Sarah; Clayton, Katie; Dinsmore, John; Floyd, Siobhan; Hoadley, Angela; Johnson, Tony; Kalaitzaki, Eleftheria; King, Michael; Leurent, Baptiste; Maratos, Anna; O’Neill, Francis A; Osborn, David P; Patterson, Sue; Soteriou, Tony; Tyrer, Peter; Waller, Diane
2012-01-01
Objectives To evaluate the clinical effectiveness of group art therapy for people with schizophrenia and to test whether any benefits exceed those of an active control treatment. Design Three arm, rater blinded, pragmatic, randomised controlled trial. Setting Secondary care services across 15 sites in the United Kingdom. Participants 417 people aged 18 or over, who had a diagnosis of schizophrenia and provided written informed consent to take part in the study. Interventions Participants, stratified by site, were randomised to 12 months of weekly group art therapy plus standard care, 12 months of weekly activity groups plus standard care, or standard care alone. Art therapy and activity groups had up to eight members and lasted for 90 minutes. In art therapy, members were given access to a range of art materials and encouraged to use these to express themselves freely. Members of activity groups were offered various activities that did not involve use of art or craft materials and were encouraged to collectively select those they wanted to pursue. Main outcome measures The primary outcomes were global functioning, measured using the global assessment of functioning scale, and mental health symptoms, measured using the positive and negative syndrome scale, 24 months after randomisation. Main secondary outcomes were levels of group attendance, social functioning, and satisfaction with care at 12 and 24 months. Results 417 participants were assigned to either art therapy (n=140), activity groups (n=140), or standard care alone (n=137). Primary outcomes between the three study arms did not differ. The adjusted mean difference between art therapy and standard care at 24 months on the global assessment of functioning scale was −0.9 (95% confidence interval −3.8 to 2.1), and on the positive and negative syndrome scale was 0.7 (−3.1 to 4.6). Secondary outcomes did not differ between those referred to art therapy or those referred to standard care at 12 or 24 months. Conclusions Referring people with established schizophrenia to group art therapy as delivered in this trial did not improve global functioning, mental health, or other health related outcomes. Trial registration Current Controlled Trials ISRCTN46150447. PMID:22374932
Levodopa modulates small-world architecture of functional brain networks in Parkinson's disease.
Berman, Brian D; Smucny, Jason; Wylie, Korey P; Shelton, Erika; Kronberg, Eugene; Leehey, Maureen; Tregellas, Jason R
2016-11-01
PD is associated with disrupted connectivity to a large number of distributed brain regions. How the disease alters the functional topological organization of the brain, however, remains poorly understood. Furthermore, how levodopa modulates network topology in PD is largely unknown. The objective of this study was to use resting-state functional MRI and graph theory to determine how small-world architecture is altered in PD and affected by levodopa administration. Twenty-one PD patients and 20 controls underwent functional MRI scanning. PD patients were scanned off medication and 1 hour after 200 mg levodopa. Imaging data were analyzed using 226 nodes comprising 10 intrinsic brain networks. Correlation matrices were generated for each subject and converted into cost-thresholded, binarized adjacency matrices. Cost-integrated whole-brain global and local efficiencies were compared across groups and tested for relationships with disease duration and severity. Data from 2 patients and 4 controls were excluded because of excess motion. Patients off medication showed no significant changes in global efficiency and overall local efficiency, but in a subnetwork analysis did show increased local efficiency in executive (P = 0.006) and salience (P = 0.018) networks. Levodopa significantly decreased local efficiency (P = 0.039) in patients except within the subcortical network, in which it significantly increased local efficiency (P = 0.007). Levodopa modulates global and local efficiency measures of small-world topology in PD, suggesting that degeneration of nigrostriatal neurons in PD may be associated with a large-scale network reorganization and that levodopa tends to normalize the disrupted network topology in PD. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.
Large conservation gains possible for global biodiversity facets.
Pollock, Laura J; Thuiller, Wilfried; Jetz, Walter
2017-06-01
Different facets of biodiversity other than species numbers are increasingly appreciated as critical for maintaining the function of ecosystems and their services to humans. While new international policy and assessment processes such as the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) recognize the importance of an increasingly global, quantitative and comprehensive approach to biodiversity protection, most insights are still focused on a single facet of biodiversity-species. Here we broaden the focus and provide an evaluation of how much of the world's species, functional and phylogenetic diversity of birds and mammals is currently protected and the scope for improvement. We show that the large existing gaps in the coverage for each facet of diversity could be remedied by a slight expansion of protected areas: an additional 5% of the land has the potential to more than triple the protected range of species or phylogenetic or functional units. Further, the same areas are often priorities for multiple diversity facets and for both taxa. However, we find that the choice of conservation strategy has a fundamental effect on outcomes. It is more difficult (that is, requires more land) to maximize basic representation of the global biodiversity pool than to maximize local diversity. Overall, species and phylogenetic priorities are more similar to each other than they are to functional priorities, and priorities for the different bird biodiversity facets are more similar than those of mammals. Our work shows that large gains in biodiversity protection are possible, while also highlighting the need to explicitly link desired conservation objectives and biodiversity metrics. We provide a framework and quantitative tools to advance these goals for multi-faceted biodiversity conservation.
Pasco, Paul Matthew D; Jamora, Roland Dominic G; Rosales, Raymond L; Diesta, Cid Czarina E; Ng, Arlene R; Teleg, Rosalia A; Go, Criscely L; Lee, Lillian; Fernandez, Hubert H
2017-01-01
X-linked dystonia-parkinsonism(XDP) is a neurodegenerative disorder endemic to the Philippines. A rating scale was developed by the authors under the guidance of the Movement Disorder Society of the Philippines (MDSP) to assess XDP severity and progression, functional impact, and response to treatment in future clinical trials. Our main objective was to validate our new scale, the XDP-MDSP scale. The initial validation process included pragmatic testing to XDP patients followed by a modified Delphi procedure with an international advisory panel of dystonia, parkinsonism and scale development experts. Pearson correlation was used to assess construct validity of our new scale versus the assess construct validity of our new scale versus standard dystonia, parkinsonism, non-motor and functional scales; and also to assess divergent validity against behavioral and cognitive scales. The 37-item XDP-MDSP scale has five parts: I-dystonia, II-parkinsonism, III-non-motor features, IV-ADL, and V-global impression. After initial validation, the scale was administered to 204 XDP patients. Inter-domain correlation for the first four parts was acceptable. The correlation between these domains and the global rating was slightly lower. Correlations between Parts I, II, III, and IV versus standard dystonia, parkinsonism, non-motor and functional scales were acceptable with values ranging from 0.323 to 0.428. For divergent validity, a significant correlation was seen with behavioral scales. No significant correlation was noted with the cognitive scale. The proposed XDP-MDSP scale is internally valid but the global rating subscale may need to be modified or eliminated. While there is convergent validity, divergent validation was successful only on cognitive and not behavioral scales. The frequent co-occurrence of anxiety and depression, and its effect on the motor and functional state, may explain this finding.
Large conservation gains possible for global biodiversity facets
NASA Astrophysics Data System (ADS)
Pollock, Laura J.; Thuiller, Wilfried; Jetz, Walter
2017-06-01
Different facets of biodiversity other than species numbers are increasingly appreciated as critical for maintaining the function of ecosystems and their services to humans. While new international policy and assessment processes such as the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) recognize the importance of an increasingly global, quantitative and comprehensive approach to biodiversity protection, most insights are still focused on a single facet of biodiversity—species. Here we broaden the focus and provide an evaluation of how much of the world’s species, functional and phylogenetic diversity of birds and mammals is currently protected and the scope for improvement. We show that the large existing gaps in the coverage for each facet of diversity could be remedied by a slight expansion of protected areas: an additional 5% of the land has the potential to more than triple the protected range of species or phylogenetic or functional units. Further, the same areas are often priorities for multiple diversity facets and for both taxa. However, we find that the choice of conservation strategy has a fundamental effect on outcomes. It is more difficult (that is, requires more land) to maximize basic representation of the global biodiversity pool than to maximize local diversity. Overall, species and phylogenetic priorities are more similar to each other than they are to functional priorities, and priorities for the different bird biodiversity facets are more similar than those of mammals. Our work shows that large gains in biodiversity protection are possible, while also highlighting the need to explicitly link desired conservation objectives and biodiversity metrics. We provide a framework and quantitative tools to advance these goals for multi-faceted biodiversity conservation.
Verrocchio, Maria C.; Marchetti, Daniela; Fulcheri, Mario
2015-01-01
Objective: The objective of this research was to identify retrospectively the alienating behaviors and the parental bonding that occurred in an Italian sample of adults whose had parents separated or divorced and their associations with self-esteem and psychological distress. Methods: Four hundred seventy adults in Chieti, Italy, completed an anonymous and confidential survey regarding their childhood exposure to parental alienating behaviors (using the Baker Strategy Questionnaire), quality of the parent–child relationship (using Parental Bonding Instruments), self-esteem (using Rosenberg Self-Esteem Scale), and global psychological distress (using Global Severity Index of Symptom Checklist-90-Revised). Results: About 80% of the sample reported some exposure to parental alienating behaviors; about 65–70% of the sample has perceived non-optimal parenting by mother and by father; individuals who experienced affectionless control (low care and high overprotection) reported significantly higher exposure to parental loyalty conflict behaviors. Overall rates of reported exposure to low care, and overprotection and parental loyalty conflict behaviors were statistically significantly associated with self-esteem as well as the measure of current psychological distress. Results revealed that exposure to parental loyalty conflict behaviors and self-esteem were associated with psychological distress over and above the effects of parental bonding and age. Conclusion: The pattern of findings supports the theory that children exposed to dysfunctional parenting, and with low self-esteem are at risk for their long-term psychological functioning. Implications for health policy changes and strengthening social services are discussed. PMID:26635670
Science Writers' Guide to TERRA
NASA Technical Reports Server (NTRS)
2000-01-01
The launch of NASA's Terra spacecraft marks a new era of comprehensive monitoring of the Earth's atmosphere, oceans, and continents from a single space-based platform. Data from the five Terra instruments will create continuous, long-term records of the state of the land, oceans, and atmosphere. Together with data from other satellite systems launched by NASA and other countries, Terra will inaugurate a new self-consistent data record that will be gathered over the next 15 years. The science objectives of NASAs Earth Observing System (EOS) program are to provide global observations and scientific understanding of land cover change and global productivity, climate variability and change, natural hazards, and atmospheric ozone. Observations by the Terra instruments will: provide the first global and seasonal measurements of the Earth system, including such critical functions as biological productivity of the land and oceans, snow and ice, surface temperature, clouds, water vapor, and land cover; improve our ability to detect human impacts on the Earth system and climate, identify the "fingerprint" of human activity on climate, and predict climate change by using the new global observations in climate models; help develop technologies for disaster prediction, characterization, and risk reduction from wildfires, volcanoes, floods, and droughts, and start long-term monitoring of global climate change and environmental change.
NASA Astrophysics Data System (ADS)
Xing, Lizhi; Dong, Xianlei; Guan, Jun
2017-04-01
Input-output table is very comprehensive and detailed in describing the national economic system with lots of economic relationships, which contains supply and demand information among industrial sectors. The complex network, a theory and method for measuring the structure of complex system, can describe the structural characteristics of the internal structure of the research object by measuring the structural indicators of the social and economic system, revealing the complex relationship between the inner hierarchy and the external economic function. This paper builds up GIVCN-WIOT models based on World Input-Output Database in order to depict the topological structure of Global Value Chain (GVC), and assumes the competitive advantage of nations is equal to the overall performance of its domestic sectors' impact on the GVC. Under the perspective of econophysics, Global Industrial Impact Coefficient (GIIC) is proposed to measure the national competitiveness in gaining information superiority and intermediate interests. Analysis of GIVCN-WIOT models yields several insights including the following: (1) sectors with higher Random Walk Centrality contribute more to transmitting value streams within the global economic system; (2) Half-Value Ratio can be used to measure robustness of open-economy macroeconomics in the process of globalization; (3) the positive correlation between GIIC and GDP indicates that one country's global industrial impact could reveal its international competitive advantage.
Salomé, F; Petitjean, F; Germain, C; Demant, J-C
2004-01-01
Most studies on the quality of life (Qol) of patients with schizophrenia deal with objective living conditions and how they are perceived by hospitalized patients. The few studies that compare Qol for patients treated in part time services with the Qol of ambulatory patients do not show any significant difference in terms of subjective Qol. Some stu-dies evaluate the influence of psychopathology and needs (or expectations) on the subjective Qol in these groups of patients. Available data indicate that the general well-being is influenced by psychopathology (positive, negative or depressive symptoms) and unmet needs in ambulatory patients. They also show that subjective Qol in certain life domains (social relations, family relations, leisure, health, law and security) is influenced by negative symptoms, anxiety and depression in patients treated in part-time services. The aim of this study is to compare the objective and subjective Qol of patients with schizophrenia treated in part time services (day hospital and day care center) to the Qol of out-patients treated on a purely ambulatory basis (out patient clinic). We studied the Qol of 2 groups of 30 patients with schizophrenia (ICD 10 criteria) treated in various centers. The first group was made of ambulatory patients, the second one was constituted of patients treated in a day hospital or a day care center. Patients were matched for age, duration of illness, number of hospitalizations. The instruments used for rating were the following: Clinical Global Impression (CGI), Global Assessment of Functioning (GAF), Positive And Negative Symptoms Scale (PANSS), Drug Attitude Inventory (DAI-10). The Qol was measured with a french version of the Lancashire Quality Of Life Profile (LQOLP) (Salomé, Germain, Petitjean, Demant and Boyer, 2000). This instrument measures the objective Qol as well as the subjective Qol. It does possess satisfying psychometric properties and offers the possibility to establish Qol profiles. All Qol ratings were carried out by a clinician who was not involved in the treatment of the patients. When the 2 groups are compared our results indicate that ambulatory patients are less symptomatic, have a better level of functioning and a better objective Qol in such domains as: finances, living situation, family relations and health. There is no significant difference in terms of anxiety and depression as measured by the respective items of the PANSS. Patients treated in part-time services present higher scores of positive symptoms. Our results indicate that there is no significant difference for subjective Qol variables between the two groups, except for general well-being, that tends to be higher in ambulatory patients. When exploring the influence of clinical data on the Qol in each group, we find negative correlations in ambulatory patients between various domains of subjective Qol and illness severity (law and security, family relations, social relations, general well-being), global functioning (family relations, social relation, health) and positive symptoms (living conditions, law and security, family relations, social relations, health). In this same group, the subjective Qol for family relations is significantly correlated with several expectations in terms of Qol improvement (leisure, social relations, family relations, transport, work). In these patients, the subjective Qol for social relations is also significantly correlated with their expectations in terms of Qol improvement (work, money, lodging, affective relations, transport). There is no significant correlation between subjective Qol and expectations in patients treated in part-time services. Our results indicate that part time services treat schizophrenic patients with a lower level of global functioning and a higher level of symptom severity compared with ambulatory patients. These results confirm other studies that show no significant difference between these 2 groups in terms of subjective Qol. The subjective Qol in the field of relations (family and social) in ambulatory patients seems particularly sensitive to illness severity, positive symptoms and global functioning level. This has also been reported by other studies. In patients treated in part-time services, the subjective Qol, particularly for living conditions and security, seems sensitive to anxiety and depression. This has also been shown by other studies. Finally, our results underline the importance of patients' expectations in terms of subjective Qol, particularly in the field of relations (family and social) for ambulatory patients.
Healthcare provider education: from institutional boxes to dynamic networks.
Eisler, George
2009-01-01
The world recognizes the need for close collaboration in planning between the healthcare system and the post-secondary education system; this has also been advocated in the lead article. Forums and mechanisms to facilitate this collaboration are being implemented from local to global environments. Beyond the focus on competency gaps, there are important functional co-dependencies between healthcare and post-secondary education, including the need for a more formalized continuous quality improvement approach at the inter-organizational system level. The case for this close and continuous collaborative relationship is based on the following: (1) a close functional relationship, (2) joint responsibility for healthcare provider education, (3) the urgent need to address the workforce and education strategies for almost all healthcare services areas and (4) the factors that characterize successful and sustained quality improvement in complex adaptive systems. A go-forward vision consisting of an integrated web of academic health networks is proposed, each with its particular shared vision and aligned with an overall vision for healthcare in each provincial jurisdiction, as well as with national and global healthcare objectives.
The q-G method : A q-version of the Steepest Descent method for global optimization.
Soterroni, Aline C; Galski, Roberto L; Scarabello, Marluce C; Ramos, Fernando M
2015-01-01
In this work, the q-Gradient (q-G) method, a q-version of the Steepest Descent method, is presented. The main idea behind the q-G method is the use of the negative of the q-gradient vector of the objective function as the search direction. The q-gradient vector, or simply the q-gradient, is a generalization of the classical gradient vector based on the concept of Jackson's derivative from the q-calculus. Its use provides the algorithm an effective mechanism for escaping from local minima. The q-G method reduces to the Steepest Descent method when the parameter q tends to 1. The algorithm has three free parameters and it is implemented so that the search process gradually shifts from global exploration in the beginning to local exploitation in the end. We evaluated the q-G method on 34 test functions, and compared its performance with 34 optimization algorithms, including derivative-free algorithms and the Steepest Descent method. Our results show that the q-G method is competitive and has a great potential for solving multimodal optimization problems.
Separating the Sheep from the Goats: Differentiating Global Categories.
ERIC Educational Resources Information Center
Mandler, Jean M.; And Others
1991-01-01
The conceptual categories that children have developed in their second year were studied in five experiments using object manipulation tasks. Subjects included 152 children from 18 to 31 months of age. These very young children had formed global conceptions of many domains of objects. (SLD)
ERIC Educational Resources Information Center
Longstreet, Wilma S., Ed.
1988-01-01
This issue contains an introduction ("The Promise and Perplexity of Globalism," by W. Longstreet) and seven articles dedicated to exploring the meaning of global education for today's schools. "Global Education: An Overview" (J. Becker) develops possible definitions, identifies objectives and skills, and addresses questions and…
Microvascular endothelial function and cognitive performance: The ELSA-Brasil cohort study.
Brant, Luisa; Bos, Daniel; Araujo, Larissa Fortunato; Ikram, M Arfan; Ribeiro, Antonio Lp; Barreto, Sandhi M
2018-06-01
Impaired microvascular endothelial function may be implicated in the etiology of cognitive decline. Yet, current data on this association are inconsistent. Our objective is to investigate the relation of microvascular endothelial function to cognitive performance in the ELSA-Brasil cohort study. A total of 1521 participants from ELSA-Brasil free of dementia underwent peripheral arterial tonometry (PAT) to quantify microvascular endothelial function (PAT-ratio and mean baseline pulse amplitude (BPA)) and cognitive tests that covered the domains of memory, verbal fluency, and executive function at baseline. Cognitive tests in participants aged 55 years old and above were repeated during the second examination (mean follow-up: 3.5 (0.3) years). Linear regression and generalized linear models were used to evaluate the association between endothelial function, global cognitive performance, and performance on specific cognitive domains. In unadjusted cross-sectional analyses, we found that BPA and PAT-ratio were associated with worse global cognitive performance (mean difference for BPA: -0.07, 95% CI: -0.11; -0.03, p<0.01; mean difference for PAT-ratio: 0.11, 95% CI: 0.01; 0.20, p=0.02), worse performance on learning, recall, and word recognition tests (BPA: -0.87, 95% CI: -1.21; -0.52, p<0.01; PAT-ratio: 1.58, 95% CI: 0.80; 2.36, p<0.01), and only BPA was associated with worse performance in verbal fluency tests (-0.70, 95% CI: -1.19; -0.21, p<0.01). Adjustments for age, sex, and level of education rendered the associations statistically non-significant. Longitudinally, there was no association between microvascular endothelial and cognitive functions. The associations between microvascular endothelial function and cognition are explained by age, sex, and educational level. Measures of microvascular endothelial function may be of limited value with regard to preclinical cognitive deficits.
NASA Astrophysics Data System (ADS)
Sahraei, S.; Asadzadeh, M.
2017-12-01
Any modern multi-objective global optimization algorithm should be able to archive a well-distributed set of solutions. While the solution diversity in the objective space has been explored extensively in the literature, little attention has been given to the solution diversity in the decision space. Selection metrics such as the hypervolume contribution and crowding distance calculated in the objective space would guide the search toward solutions that are well-distributed across the objective space. In this study, the diversity of solutions in the decision-space is used as the main selection criteria beside the dominance check in multi-objective optimization. To this end, currently archived solutions are clustered in the decision space and the ones in less crowded clusters are given more chance to be selected for generating new solution. The proposed approach is first tested on benchmark mathematical test problems. Second, it is applied to a hydrologic model calibration problem with more than three objective functions. Results show that the chance of finding more sparse set of high-quality solutions increases, and therefore the analyst would receive a well-diverse set of options with maximum amount of information. Pareto Archived-Dynamically Dimensioned Search, which is an efficient and parsimonious multi-objective optimization algorithm for model calibration, is utilized in this study.
Global astrometry with the space interferometry mission
NASA Technical Reports Server (NTRS)
Boden, A.; Unwin, S.; Shao, M.
1997-01-01
The prospects for global astrometric measurements with the space interferometry mission (SIM) are discussed. The SIM mission will perform four microarcsec astrometric measurements on objects as faint as 20 mag using the optical interferometry technique with a 10 m baseline. The SIM satellite will perform narrow angle astrometry and global astrometry by means of an astrometric grid. The sensitivities of the SIM global astrometric performance and the grid accuracy versus instrumental parameters and sky coverage schemes are reported on. The problems in finding suitable astrometric grid objects to support microarcsec astrometry, and related ground-based observation programs are discussed.
NASA Astrophysics Data System (ADS)
Mouffe, Melodie; Getirana, Augusto; Ricci, Sophie; Lion, Christine; Biancamaria, Sylvian; Boone, Aaron; Mognard, Nelly; Rogel, Philippe
2013-09-01
The Surface Water and Ocean Topography (SWOT) wide swath altimetry mission will provide measurements of water surface elevations (WSE) at a global scale. The aim of this study is to investigate the potential of these satellite data for the calibration of the hydrological model HyMAP, over the Amazon river basin. Since SWOT has not yet been launched, synthetical observations are used to calibrate the river bed depth and width, the Manning coefficient and the baseflow concentration time. The calibration process stands in the minimization of a cost function using an evolutionnary, global and multi-objective algorithm that describes the difference between the simulated and the observed WSE. We found that the calibration procedure is able to retrieve an optimal set of parameters such that it brings the simulated WSE closer to the observation. Still with a global calibration procedure where a uniform correction is applied, the improvement is limited to a mean correction over the catchment and the simulation period. We conclude that in order to benefit from the high resolution and complete coverage of the SWOT mission, the calibration process should be achieved sequentially in time over sub-domains as observations become available.
Development of an Agent-based Model to Analyze Contemporary Helium Markets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riddle, Matthew E.; Uckun, Canan; Conzelmann, Guenter
Although U.S. helium demand has remained relatively flat since 2009, exports of helium have increased significantly since then, driven primarily by demand for electronic and semiconductor manufacturing in Asia. In the midst of this global demand shift, the Helium Act dictates a new procedure for pricing and distributing the gas through a reserve that historically functioned as a loose “oligarchy.” The new procedure requires prices to be determined by the open market through auctions and a survey of market prices, as opposed to increasing prices according to the consumer price index. Response to these changes has caused temporary shortages, pricemore » increases, and a significant increase in the development of the helium extraction technologies used to produce helium from formerly marginal sources. Technologies are being developed and refined to extract helium from formerly low-yielding natural gas fields containing much lower amounts of helium than the previously considered economic threshold of 0.3%. Combining these transformative policies with the potential for new and significant global supplies from Qatar, Algeria, and Russia could lead to new and unforeseen market behaviors and reactions from global helium markets. The objective of the project is to analyze the global helium markets.« less
Global Perspectives: Some Questions and Answers.
ERIC Educational Resources Information Center
Center for Global Perspectives, New York, NY.
To enlighten the reader on the status, objectives, and needs of global education, this paper poses and answers questions related to global perspectives. A global perspective is interpreted to include heightened awareness and understanding of the global system as well as increased consciousness of the intimate relationship of self, humankind, and…
Self-awareness of memory function in Parkinson's disease in relation to mood and symptom severity.
Sitek, Emilia J; Sołtan, Witold; Wieczorek, Dariusz; Robowski, Piotr; Sławek, Jarosław
2011-03-01
In clinical practice, discrepancies are observed between self and proxy reports of various aspects of Parkinson's disease (PD). This study aimed at assessing self-awareness of memory function in PD both by comparing patients' and caregivers' questionnaire ratings of the patients' memory and by correlating subjective ratings with verbal learning results. Forty-five patient-proxy pairs participated in the study. Self-Rating Scale of Memory Functions was used as a questionnaire subjective measure. Auditory Verbal Learning Test (AVLT) was applied to assess verbal memory, Stroop test to assess cognitive control and Mini-Mental State Examination (MMSE) for global cognitive assessment. Patient self-reports did not diverge appreciably from proxy reports when global scores were considered, but patient-proxy consistency was low for individual items with the exception of those referring to verbal recall. Both patient and proxy ratings were moderately correlated with the objective measures. Patient-proxy discrepancies were associated with lower verbal learning, poor cognitive control and more severe PD symptomatology. Moreover, depression was associated with patients' overestimation of symptoms. Self-awareness of memory function is relatively well preserved in PD, but is negatively affected by depressive symptoms. Patient-proxy discrepancies increase also with disease severity, degree of memory problems and cognitive control deficits. Caregivers seem to be unaware of the specificity of memory problems in PD and report only some of them, mainly those related to verbal recall.
Salari, Elham; Mahmoudi-Gharaei, Javad; Shirazi, Elham; Sepasi, Mitra
2018-01-01
Objective Parents play an important role in development and continuation of anxiety disorders in children. Yet the evidence on parent contribution in cognitive behavioral therapy (CBT) for childhood anxiety is limited. This open randomized trial examined the effectiveness of a parent-directed group CBT to manage children with anxiety disorders. Method Parents of 42 children aged 6–12 with primary anxiety disorders were allocated to a six, two-hour weekly intervention and a wait-list (WL) control. The Revised Children’s Manifest Anxiety, Children’s Depression Inventory, Strengths and Difficulties Questionnaire-Home Version, Depression-Anxiety-Stress Scale, Children Global Assessment Scale, and Global Relational Assessment of Functioning were used to assess children’s and parents’ functioning and emotional symptoms. Parents completed consumer satisfaction questionnaire. Results Parents in the CBT group reported significant improvement in their depressive symptoms (p=0.006) and the family functioning (p=0.04), as well as reduction in children’s emotional symptoms (p=0.007). Clinician rating of children’s functioning showed significant improvement in the CBT group(p=0.001). There was no significant difference in children rating of their anxiety within groups from pre- to post-intervention. Parents were satisfied mostly with the intervention. Conclusion A brief parent-only CBT based intervention can be effective in the management of childhood anxiety. PMID:29662524
Developing CORBA-Based Distributed Scientific Applications from Legacy Fortran Programs
NASA Technical Reports Server (NTRS)
Sang, Janche; Kim, Chan; Lopez, Isaac
2000-01-01
Recent progress in distributed object technology has enabled software applications to be developed and deployed easily such that objects or components can work together across the boundaries of the network, different operating systems, and different languages. A distributed object is not necessarily a complete application but rather a reusable, self-contained piece of software that co-operates with other objects in a plug-and-play fashion via a well-defined interface. The Common Object Request Broker Architecture (CORBA), a middleware standard defined by the Object Management Group (OMG), uses the Interface Definition Language (IDL) to specify such an interface for transparent communication between distributed objects. Since IDL can be mapped to any programming language, such as C++, Java, Smalltalk, etc., existing applications can be integrated into a new application and hence the tasks of code re-writing and software maintenance can be reduced. Many scientific applications in aerodynamics and solid mechanics are written in Fortran. Refitting these legacy Fortran codes with CORBA objects can increase the codes reusability. For example, scientists could link their scientific applications to vintage Fortran programs such as Partial Differential Equation(PDE) solvers in a plug-and-play fashion. Unfortunately, CORBA IDL to Fortran mapping has not been proposed and there seems to be no direct method of generating CORBA objects from Fortran without having to resort to manually writing C/C++ wrappers. In this paper, we present an efficient methodology to integrate Fortran legacy programs into a distributed object framework. Issues and strategies regarding the conversion and decomposition of Fortran codes into CORBA objects are discussed. The following diagram shows the conversion and decomposition mechanism we proposed. Our goal is to keep the Fortran codes unmodified. The conversion- aided tool takes the Fortran application program as input and helps programmers generate C/C++ header file and IDL file for wrapping the Fortran code. Programmers need to determine by themselves how to decompose the legacy application into several reusable components based on the cohesion and coupling factors among the functions and subroutines. However, programming effort still can be greatly reduced because function headings and types have been converted to C++ and IDL styles. Most Fortran applications use the COMMON block to facilitate the transfer of large amount of variables among several functions. The COMMON block plays the similar role of global variables used in C. In the CORBA-compliant programming environment, global variables can not be used to pass values between objects. One approach to dealing with this problem is to put the COMMON variables into the parameter list. We do not adopt this approach because it requires modification of the Fortran source code which violates our design consideration. Our approach is to extract the COMMON blocks and convert them into a structure-typed attribute in C++. Through attributes, each component can initialize the variables and return the computation result back to the client. We have tested successfully the proposed conversion methodology based on the f2c converter. Since f2c only translates Fortran to C, we still needed to edit the converted code to meet the C++ and IDL syntax. For example, C++/IDL requires a tag in the structure type, while C does not. In this paper, we identify the necessary changes to the f2c converter in order to directly generate the C++ header and the IDL file. Our future work is to add GUI interface to ease the decomposition task by simply dragging and dropping icons.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walker, Andrew; Lawrence, Earl
The Response Surface Modeling (RSM) Tool Suite is a collection of three codes used to generate an empirical interpolation function for a collection of drag coefficient calculations computed with Test Particle Monte Carlo (TPMC) simulations. The first code, "Automated RSM", automates the generation of a drag coefficient RSM for a particular object to a single command. "Automated RSM" first creates a Latin Hypercube Sample (LHS) of 1,000 ensemble members to explore the global parameter space. For each ensemble member, a TPMC simulation is performed and the object drag coefficient is computed. In the next step of the "Automated RSM" code,more » a Gaussian process is used to fit the TPMC simulations. In the final step, Markov Chain Monte Carlo (MCMC) is used to evaluate the non-analytic probability distribution function from the Gaussian process. The second code, "RSM Area", creates a look-up table for the projected area of the object based on input limits on the minimum and maximum allowed pitch and yaw angles and pitch and yaw angle intervals. The projected area from the look-up table is used to compute the ballistic coefficient of the object based on its pitch and yaw angle. An accurate ballistic coefficient is crucial in accurately computing the drag on an object. The third code, "RSM Cd", uses the RSM generated by the "Automated RSM" code and the projected area look-up table generated by the "RSM Area" code to accurately compute the drag coefficient and ballistic coefficient of the object. The user can modify the object velocity, object surface temperature, the translational temperature of the gas, the species concentrations of the gas, and the pitch and yaw angles of the object. Together, these codes allow for the accurate derivation of an object's drag coefficient and ballistic coefficient under any conditions with only knowledge of the object's geometry and mass.« less
Dearborn, Peter J; Elias, Merrill F; Sullivan, Kevin J; Sullivan, Cara E; Robbins, Michael A
2018-06-21
Prior studies have found associations between visual acuity (VA) and cognitive function. However, these studies used a limited range of cognitive measures and did not control for cardiovascular disease risk factors (CVD-RFs) and baseline function. The primary objective of this study was to analyze the associations of VA and cognitive performance using a thorough neuropsychological test battery. This study used community-dwelling sample data across the sixth (2001-2006) and seventh (2006-2010) waves of the Maine-Syracuse Longitudinal Study (n=655). Wave 6 VA as measured by the Snellen Eye Test was the primary predictor of wave 6 and wave 7 Global cognitive performance, Visual-Spatial Organization and Memory, Verbal Episodic Memory, Working Memory, Scanning and Tracking, and Executive Function. Additionally, VA was used to predict longitudinal changes in wave 7 cognitive performance (wave 6 performance adjusted). We analyzed these relationships with multiple linear and logistic regression models adjusted for age, sex, education, ethnicity, depressive symptoms, physical function deficits in addition to CVD-RFs, chronic kidney disease, homocysteine, continuous systolic blood pressure, and hypertension status. Adjusted for demographic covariates and CVD-RFs, poorer VA was associated with concurrent and approximate 5-year declines in Global cognitive function, Visual-Spatial Organization and Memory, and Verbal Episodic Memory. VA may be used in combination with other screening measures to determine risk for cognitive decline. (JINS, 2018, 24, 1-9).
Advanced functional network analysis in the geosciences: The pyunicorn package
NASA Astrophysics Data System (ADS)
Donges, Jonathan F.; Heitzig, Jobst; Runge, Jakob; Schultz, Hanna C. H.; Wiedermann, Marc; Zech, Alraune; Feldhoff, Jan; Rheinwalt, Aljoscha; Kutza, Hannes; Radebach, Alexander; Marwan, Norbert; Kurths, Jürgen
2013-04-01
Functional networks are a powerful tool for analyzing large geoscientific datasets such as global fields of climate time series originating from observations or model simulations. pyunicorn (pythonic unified complex network and recurrence analysis toolbox) is an open-source, fully object-oriented and easily parallelizable package written in the language Python. It allows for constructing functional networks (aka climate networks) representing the structure of statistical interrelationships in large datasets and, subsequently, investigating this structure using advanced methods of complex network theory such as measures for networks of interacting networks, node-weighted statistics or network surrogates. Additionally, pyunicorn allows to study the complex dynamics of geoscientific systems as recorded by time series by means of recurrence networks and visibility graphs. The range of possible applications of the package is outlined drawing on several examples from climatology.
Improving Estimation of Ground Casualty Risk From Reentering Space Objects
NASA Technical Reports Server (NTRS)
Ostrom, Chris L.
2017-01-01
A recent improvement to the long-term estimation of ground casualties from reentering space debris is the further refinement and update to the human population distribution. Previous human population distributions were based on global totals with simple scaling factors for future years, or a coarse grid of population counts in a subset of the world's countries, each cell having its own projected growth rate. The newest population model includes a 5-fold refinement in both latitude and longitude resolution. All areas along a single latitude are combined to form a global population distribution as a function of latitude, creating a more accurate population estimation based on non-uniform growth at the country and area levels. Previous risk probability calculations used simplifying assumptions that did not account for the ellipsoidal nature of the Earth. The new method uses first, a simple analytical method to estimate the amount of time spent above each latitude band for a debris object with a given orbit inclination and second, a more complex numerical method that incorporates the effects of a non-spherical Earth. These new results are compared with the prior models to assess the magnitude of the effects on reentry casualty risk.
Improving Estimation of Ground Casualty Risk from Reentering Space Objects
NASA Technical Reports Server (NTRS)
Ostrom, C.
2017-01-01
A recent improvement to the long-term estimation of ground casualties from reentering space debris is the further refinement and update to the human population distribution. Previous human population distributions were based on global totals with simple scaling factors for future years, or a coarse grid of population counts in a subset of the world's countries, each cell having its own projected growth rate. The newest population model includes a 5-fold refinement in both latitude and longitude resolution. All areas along a single latitude are combined to form a global population distribution as a function of latitude, creating a more accurate population estimation based on non-uniform growth at the country and area levels. Previous risk probability calculations used simplifying assumptions that did not account for the ellipsoidal nature of the earth. The new method uses first, a simple analytical method to estimate the amount of time spent above each latitude band for a debris object with a given orbit inclination, and second, a more complex numerical method that incorporates the effects of a non-spherical Earth. These new results are compared with the prior models to assess the magnitude of the effects on reentry casualty risk.
Topology of molecular interaction networks.
Winterbach, Wynand; Van Mieghem, Piet; Reinders, Marcel; Wang, Huijuan; de Ridder, Dick
2013-09-16
Molecular interactions are often represented as network models which have become the common language of many areas of biology. Graphs serve as convenient mathematical representations of network models and have themselves become objects of study. Their topology has been intensively researched over the last decade after evidence was found that they share underlying design principles with many other types of networks.Initial studies suggested that molecular interaction network topology is related to biological function and evolution. However, further whole-network analyses did not lead to a unified view on what this relation may look like, with conclusions highly dependent on the type of molecular interactions considered and the metrics used to study them. It is unclear whether global network topology drives function, as suggested by some researchers, or whether it is simply a byproduct of evolution or even an artefact of representing complex molecular interaction networks as graphs.Nevertheless, network biology has progressed significantly over the last years. We review the literature, focusing on two major developments. First, realizing that molecular interaction networks can be naturally decomposed into subsystems (such as modules and pathways), topology is increasingly studied locally rather than globally. Second, there is a move from a descriptive approach to a predictive one: rather than correlating biological network topology to generic properties such as robustness, it is used to predict specific functions or phenotypes.Taken together, this change in focus from globally descriptive to locally predictive points to new avenues of research. In particular, multi-scale approaches are developments promising to drive the study of molecular interaction networks further.
Topology of molecular interaction networks
2013-01-01
Molecular interactions are often represented as network models which have become the common language of many areas of biology. Graphs serve as convenient mathematical representations of network models and have themselves become objects of study. Their topology has been intensively researched over the last decade after evidence was found that they share underlying design principles with many other types of networks. Initial studies suggested that molecular interaction network topology is related to biological function and evolution. However, further whole-network analyses did not lead to a unified view on what this relation may look like, with conclusions highly dependent on the type of molecular interactions considered and the metrics used to study them. It is unclear whether global network topology drives function, as suggested by some researchers, or whether it is simply a byproduct of evolution or even an artefact of representing complex molecular interaction networks as graphs. Nevertheless, network biology has progressed significantly over the last years. We review the literature, focusing on two major developments. First, realizing that molecular interaction networks can be naturally decomposed into subsystems (such as modules and pathways), topology is increasingly studied locally rather than globally. Second, there is a move from a descriptive approach to a predictive one: rather than correlating biological network topology to generic properties such as robustness, it is used to predict specific functions or phenotypes. Taken together, this change in focus from globally descriptive to locally predictive points to new avenues of research. In particular, multi-scale approaches are developments promising to drive the study of molecular interaction networks further. PMID:24041013
Mcalister, Courtney; Schmitter-Edgecombe, Maureen; Lamb, Richard
2016-03-01
The objective of this meta-analysis was to improve understanding of the heterogeneity in the relationship between cognition and functional status in individuals with mild cognitive impairment (MCI). Demographic, clinical, and methodological moderators were examined. Cognition explained an average of 23% of the variance in functional outcomes. Executive function measures explained the largest amount of variance (37%), whereas global cognitive status and processing speed measures explained the least (20%). Short- and long-delayed memory measures accounted for more variance (35% and 31%) than immediate memory measures (18%), and the relationship between cognition and functional outcomes was stronger when assessed with informant-report (28%) compared with self-report (21%). Demographics, sample characteristics, and type of everyday functioning measures (i.e., questionnaire, performance-based) explained relatively little variance compared with cognition. Executive functioning, particularly measured by Trails B, was a strong predictor of everyday functioning in individuals with MCI. A large proportion of variance remained unexplained by cognition. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Active printed materials for complex self-evolving deformations.
Raviv, Dan; Zhao, Wei; McKnelly, Carrie; Papadopoulou, Athina; Kadambi, Achuta; Shi, Boxin; Hirsch, Shai; Dikovsky, Daniel; Zyracki, Michael; Olguin, Carlos; Raskar, Ramesh; Tibbits, Skylar
2014-12-18
We propose a new design of complex self-evolving structures that vary over time due to environmental interaction. In conventional 3D printing systems, materials are meant to be stable rather than active and fabricated models are designed and printed as static objects. Here, we introduce a novel approach for simulating and fabricating self-evolving structures that transform into a predetermined shape, changing property and function after fabrication. The new locally coordinated bending primitives combine into a single system, allowing for a global deformation which can stretch, fold and bend given environmental stimulus.
Active Printed Materials for Complex Self-Evolving Deformations
Raviv, Dan; Zhao, Wei; McKnelly, Carrie; Papadopoulou, Athina; Kadambi, Achuta; Shi, Boxin; Hirsch, Shai; Dikovsky, Daniel; Zyracki, Michael; Olguin, Carlos; Raskar, Ramesh; Tibbits, Skylar
2014-01-01
We propose a new design of complex self-evolving structures that vary over time due to environmental interaction. In conventional 3D printing systems, materials are meant to be stable rather than active and fabricated models are designed and printed as static objects. Here, we introduce a novel approach for simulating and fabricating self-evolving structures that transform into a predetermined shape, changing property and function after fabrication. The new locally coordinated bending primitives combine into a single system, allowing for a global deformation which can stretch, fold and bend given environmental stimulus. PMID:25522053
Beyond Worst-Case Analysis in Privacy and Clustering: Exploiting Explicit and Implicit Assumptions
2013-08-01
Dwork et al [63]. Given a query function f , the curator first estimates the global sensitivity of f , denoted GS(f) = maxD,D′ f(D)− f(D′), then outputs f...Ostrovsky et al [121]. Ostrovsky et al study instances in which the ratio between the cost of the optimal (k − 1)-means solu- tion and the cost of the...k-median objective. We also build on the work of Balcan et al [25] that investigate the connection between point-wise approximations of the target
Solving SAT Problem Based on Hybrid Differential Evolution Algorithm
NASA Astrophysics Data System (ADS)
Liu, Kunqi; Zhang, Jingmin; Liu, Gang; Kang, Lishan
Satisfiability (SAT) problem is an NP-complete problem. Based on the analysis about it, SAT problem is translated equally into an optimization problem on the minimum of objective function. A hybrid differential evolution algorithm is proposed to solve the Satisfiability problem. It makes full use of strong local search capacity of hill-climbing algorithm and strong global search capability of differential evolution algorithm, which makes up their disadvantages, improves the efficiency of algorithm and avoids the stagnation phenomenon. The experiment results show that the hybrid algorithm is efficient in solving SAT problem.
Altered brain network modules induce helplessness in major depressive disorder
Peng, Daihui; Shi, Feng; Shen, Ting; Peng, Ziwen; Zhang, Chen; Liu, Xiaohua; Qiu, Meihui; Liu, Jun; Jiang, Kaida; Shen, Dinggang
2017-01-01
Objective The abnormal brain functional connectivity (FC) has been assumed to be a pathophysiological aspect of major depressive disorder (MDD). However, it is poorly understood, regarding the underlying patterns of global FC network and their relationships with the clinical characteristics of MDD. Methods Resting-state functional magnetic resonance imaging data were acquired from 16 first episode, medication-naïve MDD patients and 16 healthy control subjects. The global FC network was constructed using 90 brain regions. The global topological patterns, e.g., small-worldness and modularity, and their relationships with depressive characteristics were investigated. Furthermore, the participant coefficient and module degree of MDD patients were measured to reflect the regional roles in module network, and the impairment of FC was examined by network based statistic. Results Small-world property was not altered in MDD. However, MDD patients exhibited 5 atypically reorganized modules compared to the controls. A positive relationship was also found among MDD patients between the intra-module I and helplessness factor evaluated via the Hamilton Depression Scale. Specifically, eight regions exhibited the abnormal participant coefficient or module degree, e.g., left superior orbital frontal cortex and right amygdala. The decreased FC was identified among the sub-network of 24 brain regions, e.g., frontal cortex, supplementary motor area, amygdala, thalamus, and hippocampus. Limitation The limited size of MDD samples precluded meaningful study of distinct clinical characteristics in relation to aberrant FC. Conclusions The results revealed altered patterns of brain module network at the global level in MDD patients, which might contribute to the feelings of helplessness. PMID:25033474
NASA Astrophysics Data System (ADS)
Bonet-García, F.; Järvi, L.; Asmi, A.; Suárez-Muñoz, M.
2016-12-01
Humanity must face enormous environmental challenges including biodiversity decline, climate change, ocean acidification, sea level rise and overpopulation. The research infrastructures (RIs) created in the last decades worldwide cover a wide range of spatial and thematic scales and collect information about the functioning of Earth ecosystems. However, we need to go one step forward: understand and simulate the functioning of the Earth as a complex system in a global change scenario. Cooperation among international RIs as well as multidisciplinary work are mandatory to achieve this challenging objective. COOP+ (EU Horizon 2020 project) aims to strengthen the links and coordination of European environmental RIs with their international counterparts. COOP+ will create cooperation threads among international research infrastructures using environmental Global Challenges (GCs) as thematic guidelines. These GCs are polyhedral and sometimes wicked problems that threaten the sustainability of our modern societies from a social and environmental perspective. This contribution describes how COOP+ uses GCs as guidelines to foster cooperation among RIs. First we have created an open survey to collect ideas about GCs within the different scientific communities. We present the structure of this survey as well as the preliminary information that it contains. The survey will be accepting responses during the project life (September 2018). We also describe the structure of a template that will be used to collaboratively characterize some selected GCs under the point of view of RIs. The main idea is to assess how RIs can be useful to address global environmental problems. We encourage all scientists related to RIs communities to participate in this process.
Considerations concerning the definition of sarcopenia.
Dawson-Hughes, B; Bischoff-Ferrari, H
2016-11-01
In this commentary, we describe the sarcopenia spectrum that results in frailty and consider the impact of several components of the frailty definition on its global prevalence. We review proposed operational definitions of sarcopenia and the extent to which they have been shown to predict hard clinical outcomes, such as hip fracture, falls, and mortality. A head-to-head comparison of nine proposed operational definitions of sarcopenia as predictors of falls revealed that the definition involving appendicular lean mass (ALM)/ht 2 alone was a significant predictor; the prevalence of sarcopenia by this definition was 11 %. We consider the strengths and limitations of definitions that include functional measurements, such as gait speed and grip strength, along with measures of lean tissue mass. The functional assessments are harder to standardize than the more objective ALM measurements. The prevalence of sarcopenia by definitions that include functional and lean mass measurements tends to be lower than the prevalence by definitions that include lean mass alone. A low prevalence limits opportunity for early identification and application of prevention strategies. For these and other reasons, it seems advantageous to base the operational definition of sarcopenia on ALM/ht 2 alone. This commentary addresses the importance of a globally applicable operational definition of sarcopenia and both desirable and undesirable features of such a definition.
Assessing Mild Cognitive Impairment among Older African Americans
Gamaldo, Alyssa A.; Allaire, Jason C.; Sims, Regina C.; Whitfield, Keith E.
2009-01-01
OBJECTIVES To examine the frequency of MCI in African American older adults. The study also plans to explore the specific cognitive domains of impairment as well as whether there are differences in demographics, health, and cognitive performance between MCI and normal participants. DESIGN Cross-sectional. SETTING Independent-living sample of urban dwelling elders in Baltimore, Maryland. PARTICIPANTS The sample consisted of 554 subjects ranging in age from 50 to 95 (mean = 68.79 ± 9.60). MEASUREMENTS Socio-demographics and health were assessed. Several cognitive measures were administered to assess inductive reasoning, declarative memory, perceptual speed, working memory, executive functioning, language, global cognitive functioning. RESULTS Approximately 22% of participants were considered MCI (i.e. 18% non-amnestic vs. 4% amnestic). A majority of the non-amnestic MCI participants had impairment in one cognitive domain, particularly language and executive function. Individuals classified as non-amnestic MCI were significantly older and had more years of education than normal individuals. The MCI groups were not significantly different than cognitively normal individuals on health factors. Individuals classified as MCI performed significantly worse on global cognitive measures as well as across specific cognitive domains than cognitively normal individuals. CONCLUSION This study demonstrates that impairment in a non-memory domain may be an early indicator of cognitive impairment, particularly among African Americans. PMID:20069588
NASA Astrophysics Data System (ADS)
Zhou, Meiling; Singh, Alok Kumar; Pedrini, Giancarlo; Osten, Wolfgang; Min, Junwei; Yao, Baoli
2018-03-01
We present a tunable output-frequency filter (TOF) algorithm to reconstruct the object from noisy experimental data under low-power partially coherent illumination, such as LED, when imaging through scattering media. In the iterative algorithm, we employ Gaussian functions with different filter windows at different stages of iteration process to reduce corruption from experimental noise to search for a global minimum in the reconstruction. In comparison with the conventional iterative phase retrieval algorithm, we demonstrate that the proposed TOF algorithm achieves consistent and reliable reconstruction in the presence of experimental noise. Moreover, the spatial resolution and distinctive features are retained in the reconstruction since the filter is applied only to the region outside the object. The feasibility of the proposed method is proved by experimental results.
Abnormal computerized dynamic posturography findings in dizzy patients with normal ENG results.
Sataloff, Robert T; Hawkshaw, Mary J; Mandel, Heidi; Zwislewski, Amy B; Armour, Jonathan; Mandel, Steven
2005-04-01
The complexities of the balance system create difficulties for professionals interested in testing equilibrium function objectively. Traditionally, electronystagmography (ENG) has been used for this purpose, but it provides information on only a limited portion of the equilibrium system. Computerized dynamic posturography (CDP) is less specific than ENG, but it provides more global insight into a patient's ability to maintain equilibrium under more challenging environmental circumstances. CD Palso appears to be valuable in obtaining objective confirmation of an abnormality in some dizzy patients whose ENG findings are normal. Our review of 33 patients with normal ENG results and abnormal CDP findings suggests that posturography is useful for confirming or quantifying a balance abnormality in some patients whose complaints cannot be confirmed by other tests frequently used by otologists.
Uncertainty Analysis of Simulated Hydraulic Fracturing
NASA Astrophysics Data System (ADS)
Chen, M.; Sun, Y.; Fu, P.; Carrigan, C. R.; Lu, Z.
2012-12-01
Artificial hydraulic fracturing is being used widely to stimulate production of oil, natural gas, and geothermal reservoirs with low natural permeability. Optimization of field design and operation is limited by the incomplete characterization of the reservoir, as well as the complexity of hydrological and geomechanical processes that control the fracturing. Thus, there are a variety of uncertainties associated with the pre-existing fracture distribution, rock mechanics, and hydraulic-fracture engineering that require evaluation of their impact on the optimized design. In this study, a multiple-stage scheme was employed to evaluate the uncertainty. We first define the ranges and distributions of 11 input parameters that characterize the natural fracture topology, in situ stress, geomechanical behavior of the rock matrix and joint interfaces, and pumping operation, to cover a wide spectrum of potential conditions expected for a natural reservoir. These parameters were then sampled 1,000 times in an 11-dimensional parameter space constrained by the specified ranges using the Latin-hypercube method. These 1,000 parameter sets were fed into the fracture simulators, and the outputs were used to construct three designed objective functions, i.e. fracture density, opened fracture length and area density. Using PSUADE, three response surfaces (11-dimensional) of the objective functions were developed and global sensitivity was analyzed to identify the most sensitive parameters for the objective functions representing fracture connectivity, which are critical for sweep efficiency of the recovery process. The second-stage high resolution response surfaces were constructed with dimension reduced to the number of the most sensitive parameters. An additional response surface with respect to the objective function of the fractal dimension for fracture distributions was constructed in this stage. Based on these response surfaces, comprehensive uncertainty analyses were conducted among input parameters and objective functions. In addition, reduced-order emulation models resulting from this analysis can be used for optimal control of hydraulic fracturing. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
Multiobjective constraints for climate model parameter choices: Pragmatic Pareto fronts in CESM1
NASA Astrophysics Data System (ADS)
Langenbrunner, B.; Neelin, J. D.
2017-09-01
Global climate models (GCMs) are examples of high-dimensional input-output systems, where model output is a function of many variables, and an update in model physics commonly improves performance in one objective function (i.e., measure of model performance) at the expense of degrading another. Here concepts from multiobjective optimization in the engineering literature are used to investigate parameter sensitivity and optimization in the face of such trade-offs. A metamodeling technique called cut high-dimensional model representation (cut-HDMR) is leveraged in the context of multiobjective optimization to improve GCM simulation of the tropical Pacific climate, focusing on seasonal precipitation, column water vapor, and skin temperature. An evolutionary algorithm is used to solve for Pareto fronts, which are surfaces in objective function space along which trade-offs in GCM performance occur. This approach allows the modeler to visualize trade-offs quickly and identify the physics at play. In some cases, Pareto fronts are small, implying that trade-offs are minimal, optimal parameter value choices are more straightforward, and the GCM is well-functioning. In all cases considered here, the control run was found not to be Pareto-optimal (i.e., not on the front), highlighting an opportunity for model improvement through objectively informed parameter selection. Taylor diagrams illustrate that these improvements occur primarily in field magnitude, not spatial correlation, and they show that specific parameter updates can improve fields fundamental to tropical moist processes—namely precipitation and skin temperature—without significantly impacting others. These results provide an example of how basic elements of multiobjective optimization can facilitate pragmatic GCM tuning processes.
Optimization of High-Dimensional Functions through Hypercube Evaluation
Abiyev, Rahib H.; Tunay, Mustafa
2015-01-01
A novel learning algorithm for solving global numerical optimization problems is proposed. The proposed learning algorithm is intense stochastic search method which is based on evaluation and optimization of a hypercube and is called the hypercube optimization (HO) algorithm. The HO algorithm comprises the initialization and evaluation process, displacement-shrink process, and searching space process. The initialization and evaluation process initializes initial solution and evaluates the solutions in given hypercube. The displacement-shrink process determines displacement and evaluates objective functions using new points, and the search area process determines next hypercube using certain rules and evaluates the new solutions. The algorithms for these processes have been designed and presented in the paper. The designed HO algorithm is tested on specific benchmark functions. The simulations of HO algorithm have been performed for optimization of functions of 1000-, 5000-, or even 10000 dimensions. The comparative simulation results with other approaches demonstrate that the proposed algorithm is a potential candidate for optimization of both low and high dimensional functions. PMID:26339237
Greening the Global Village: The Administrative Imperative To Educate Students for Global Awareness.
ERIC Educational Resources Information Center
Chaniot, Janet
The first of the three chapters of this document on teaching global education to elementary and secondary school students begins with a literature review of perspectives on global studies and continues with a comparison of definitions, assumptions, goals, and objectives for global education programs. The obstacles to teaching this global…
Visual working memory for global, object, and part-based information.
Patterson, Michael D; Bly, Benjamin Martin; Porcelli, Anthony J; Rypma, Bart
2007-06-01
We investigated visual working memory for novel objects and parts of novel objects. After a delay period, participants showed strikingly more accurate performance recognizing a single whole object than the parts of that object. This bias to remember whole objects, rather than parts, persisted even when the division between parts was clearly defined and the parts were disconnected from each other so that, in order to remember the single whole object, the participants needed to mentally combine the parts. In addition, the bias was confirmed when the parts were divided by color. These experiments indicated that holistic perceptual-grouping biases are automatically used to organize storage in visual working memory. In addition, our results suggested that the bias was impervious to top-down consciously directed control, because when task demands were manipulated through instruction and catch trials, the participants still recognized whole objects more quickly and more accurately than their parts. This bias persisted even when the whole objects were novel and the parts were familiar. We propose that visual working memory representations depend primarily on the global configural properties of whole objects, rather than part-based representations, even when the parts themselves can be clearly perceived as individual objects. This global configural bias beneficially reduces memory load on a capacity-limited system operating in a complex visual environment, because fewer distinct items must be remembered.
Makhathini, Khayelihle B; Abboussi, Oualid; Stein, Dan J; Mabandla, Musa V; Daniels, William M U
2017-08-01
Exposure to repetitive stress has a negative influence on cognitive-affective functioning, with growing evidence that these effects may be mediated by a dysregulated hypothalamic-pituitary-adrenal (HPA) axis, abnormal neurotrophic factor levels and its subsequent impact on hippocampal function. However, there are few data about the effect of repetitive stressors on epigenetic changes in the hippocampus. In the present study, we examine how repetitive restrain stress (RRS) affects cognitive-affective functioning, HPA axis regulation, brain-derived neurotrophic factor (BDNF) levels, and global hippocampal DNA methylation. RRS was induced in rats by restraining the animals for 6h per day for 28 days. The novel object recognition test (NORT) was used to assess cognitive functioning and the open field test (OFT) was performed to assess anxiety-like behavior during the last week of stress. Hippocampal BDNF levels, glucocorticoid (GR) and mineralocorticoid (MR) receptor mRNA were assessed using real-time PCR and confirmed with Western blot, while ELISAs were used to determine plasma corticosterone levels and the global methylation status of the hippocampus. Animals exposed to repetitive stress demonstrated significant alterations in the NORT and OFT, had significantly increased plasma corticosterone and significantly decreased hippocampal BDNF concentrations. The expression levels of GR and MR mRNA and protein levels of these genes were significantly decreased in the stressed group compared to control animals. The global DNA methylation of the hippocampal genome of stressed animals was also significantly decreased compared to controls. The data here are consistent with previous work emphasizing the role of the HPA axis and neurotrophic factors in mediating cognitive-affective changes after exposure to repetitive stressors. Our findings, however, extend the literature by indicating that epigenetic alterations in the hippocampal genome may also play an important role in the development of hippocampus-associated behavioral abnormalities. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.
Global Education in Elementary Schools: An Overview
ERIC Educational Resources Information Center
Anderson, Charlotte J.; Anderson, Lee F.
1977-01-01
Discussion of elementary global education covers (1) the definition and meaning of global education and (2) its objectives to achieve student competence in perceiving individual involvement, making decisions, making judgments, and exercising influence. (ND)
Strength and coherence of binocular rivalry depends on shared stimulus complexity.
Alais, David; Melcher, David
2007-01-01
Presenting incompatible images to the eyes results in alternations of conscious perception, a phenomenon known as binocular rivalry. We examined rivalry using either simple stimuli (oriented gratings) or coherent visual objects (faces, houses etc). Two rivalry characteristics were measured: Depth of rivalry suppression and coherence of alternations. Rivalry between coherent visual objects exhibits deep suppression and coherent rivalry, whereas rivalry between gratings exhibits shallow suppression and piecemeal rivalry. Interestingly, rivalry between a simple and a complex stimulus displays the same characteristics (shallow and piecemeal) as rivalry between two simple stimuli. Thus, complex stimuli fail to rival globally unless the fellow stimulus is also global. We also conducted a face adaptation experiment. Adaptation to rivaling faces improved subsequent face discrimination (as expected), but adaptation to a rivaling face/grating pair did not. To explain this, we suggest rivalry must be an early and local process (at least initially), instigated by the failure of binocular fusion, which can then become globally organized by feedback from higher-level areas when both rivalry stimuli are global, so that rivalry tends to oscillate coherently. These globally assembled images then flow through object processing areas, with the dominant image gaining in relative strength in a form of 'biased competition', therefore accounting for the deeper suppression of global images. In contrast, when only one eye receives a global image, local piecemeal suppression from the fellow eye overrides the organizing effects of global feedback to prevent coherent image formation. This indicates the primacy of local over global processes in rivalry.
Effects of Large Impacts on Mars: Implications for River Formation
NASA Technical Reports Server (NTRS)
Segura, T. L.; Toon, O. B.; Colaprete, A.; Zahnle, K.
2002-01-01
The Martian crater record provides ample evidence of the impacts of large (> 100 km) objects. These objects create hot global debris layers meters or more in depth, cause long term warming, and are capable of melting and precipitating a significant amount of water globally. Additional information is contained in the original extended abstract.
The Role of Good Form in Young Infants' Perception of Partly Occluded Objects.
ERIC Educational Resources Information Center
Johnson, Scott P.; Bremner, J. Gavin; Slater, Alan M.; Mason, Uschi C.
2000-01-01
Three experiments investigated whether 4-month-olds would attend to and utilize the global configuration ("good form") of a partly occluded, moving object to perceive its unit and coherence behind the occluder. Results indicated that curvature per se provided information in support of completion, in addition to global configuration and…
An Effective 3D Shape Descriptor for Object Recognition with RGB-D Sensors
Liu, Zhong; Zhao, Changchen; Wu, Xingming; Chen, Weihai
2017-01-01
RGB-D sensors have been widely used in various areas of computer vision and graphics. A good descriptor will effectively improve the performance of operation. This article further analyzes the recognition performance of shape features extracted from multi-modality source data using RGB-D sensors. A hybrid shape descriptor is proposed as a representation of objects for recognition. We first extracted five 2D shape features from contour-based images and five 3D shape features over point cloud data to capture the global and local shape characteristics of an object. The recognition performance was tested for category recognition and instance recognition. Experimental results show that the proposed shape descriptor outperforms several common global-to-global shape descriptors and is comparable to some partial-to-global shape descriptors that achieved the best accuracies in category and instance recognition. Contribution of partial features and computational complexity were also analyzed. The results indicate that the proposed shape features are strong cues for object recognition and can be combined with other features to boost accuracy. PMID:28245553
Learning Sequences of Actions in Collectives of Autonomous Agents
NASA Technical Reports Server (NTRS)
Turner, Kagan; Agogino, Adrian K.; Wolpert, David H.; Clancy, Daniel (Technical Monitor)
2001-01-01
In this paper we focus on the problem of designing a collective of autonomous agents that individually learn sequences of actions such that the resultant sequence of joint actions achieves a predetermined global objective. We are particularly interested in instances of this problem where centralized control is either impossible or impractical. For single agent systems in similar domains, machine learning methods (e.g., reinforcement learners) have been successfully used. However, applying such solutions directly to multi-agent systems often proves problematic, as agents may work at cross-purposes, or have difficulty in evaluating their contribution to achievement of the global objective, or both. Accordingly, the crucial design step in multiagent systems centers on determining the private objectives of each agent so that as the agents strive for those objectives, the system reaches a good global solution. In this work we consider a version of this problem involving multiple autonomous agents in a grid world. We use concepts from collective intelligence to design goals for the agents that are 'aligned' with the global goal, and are 'learnable' in that agents can readily see how their behavior affects their utility. We show that reinforcement learning agents using those goals outperform both 'natural' extensions of single agent algorithms and global reinforcement, learning solutions based on 'team games'.
The Effect of Global and Local Damping on the Perception of Hardness.
van Beek, Femke Elise; Heck, Dennis J F; Nijmeijer, Henk; Bergmann Tiest, Wouter M; Kappers, Astrid M L
2016-01-01
In tele-operation systems, damping is often injected to guarantee system stability during contact with hard objects. In this study, we used psychophysical experiments to assess the effect of adding damping on the user's perception of object hardness. In Experiments 1 and 2, combinations of stiffness and damping were tested to assess their effect on perceived hardness. In both experiments, two tasks were used: an in-contact task, starting at the object's surface, and a contact-transition task, including a free-air movement. In Experiment 3, the difference between inserting damping globally (equally throughout the workspace) and locally (inside the object only) was tested. In all experiments, the correlation between the participant's perceptual decision and force and position data was also investigated. Experiments 1 and 2 show that when injecting damping globally, perceived hardness slightly increased for an in-contact task, while it decreased considerably for a contact-transition task. Experiment 3 shows that this effect was mainly due to inserting damping globally, since there was a large perceptual difference between inserting damping globally and locally. The force and position parameters suggest that participants used the same force profile during the two movements of one trial and assessed the system's reaction to this force to perceive hardness.
Local and global evaluation for remote sensing image segmentation
NASA Astrophysics Data System (ADS)
Su, Tengfei; Zhang, Shengwei
2017-08-01
In object-based image analysis, how to produce accurate segmentation is usually a very important issue that needs to be solved before image classification or target recognition. The study for segmentation evaluation method is key to solving this issue. Almost all of the existent evaluation strategies only focus on the global performance assessment. However, these methods are ineffective for the situation that two segmentation results with very similar overall performance have very different local error distributions. To overcome this problem, this paper presents an approach that can both locally and globally quantify segmentation incorrectness. In doing so, region-overlapping metrics are utilized to quantify each reference geo-object's over and under-segmentation error. These quantified error values are used to produce segmentation error maps which have effective illustrative power to delineate local segmentation error patterns. The error values for all of the reference geo-objects are aggregated through using area-weighted summation, so that global indicators can be derived. An experiment using two scenes of very different high resolution images showed that the global evaluation part of the proposed approach was almost as effective as other two global evaluation methods, and the local part was a useful complement to comparing different segmentation results.
Yang, Hui-Ling; Chan, Pi-Tuan; Chang, Pi-Chen; Chiu, Huei-Ling; Sheen Hsiao, Shu-Tai; Chu, Hsin; Chou, Kuei-Ru
2018-02-01
A better understanding of people with cognitive disorders improves performance on memory tasks through memory-focused interventions are needed. The purpose of this study was to assess the effect of memoryfocused interventions on cognitive disorders through a meta-analysis. Systematic review and meta-analysis. The online electronic databases PubMed, the Cochrane Library, Ovid-Medline, CINHAL, PsycINFO, Ageline, and Embase (up to May 2017) were used in this study. No language restriction was applied to the search. Objective memory (learning and memory function, immediate recall, delayed recall, and recognition) was the primary indicator and subjective memory performance, global cognitive function, and depression were the secondary indicators. The Hedges' g of change, subgroup analyses, and meta-regression were analyzed on the basis of the characteristics of people with cognitive disorders. A total of 27 studies (2177 participants, mean age=75.80) reporting RCTs were included in the meta-analysis. The results indicated a medium-to-large effect of memory-focused interventions on learning and memory function (Hedges' g=0.62) and subjective memory performance (Hedges' g=0.67), a small-to-medium effect on delayed recall and depression, and a small effect on immediate recall and global cognitive function (all p<0.05) compared with the control. Subgroup analysis and meta-regression indicated that the effects on learning and memory function were more profound in the format of memory training, individual training, shorter treatment duration, and more than eight treatment sessions, and the effect size indicated the MMSE score was the most crucial indicator (β=-0.06, p=0.04). This is first comprehensive meta-analysis of special memory domains in people with cognitive disorders. The results revealed that memory-focused interventions effectively improved memory-related performance in people with cognitive disorders. An appropriately designed intervention can effectively improve memory function, reduce disability progression, and improve mood state in people with cognitive disorders. Additional randomized controlled trials including measures of recognition, global cognitive function, and depression should be conducted and analyzed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Global gray-level thresholding based on object size.
Ranefall, Petter; Wählby, Carolina
2016-04-01
In this article, we propose a fast and robust global gray-level thresholding method based on object size, where the selection of threshold level is based on recall and maximum precision with regard to objects within a given size interval. The method relies on the component tree representation, which can be computed in quasi-linear time. Feature-based segmentation is especially suitable for biomedical microscopy applications where objects often vary in number, but have limited variation in size. We show that for real images of cell nuclei and synthetic data sets mimicking fluorescent spots the proposed method is more robust than all standard global thresholding methods available for microscopy applications in ImageJ and CellProfiler. The proposed method, provided as ImageJ and CellProfiler plugins, is simple to use and the only required input is an interval of the expected object sizes. © 2016 International Society for Advancement of Cytometry. © 2016 International Society for Advancement of Cytometry.
Provoked Vestibulodynia: Does Pain Intensity Correlate With Sexual Dysfunction and Dissatisfaction?
Aerts, Leen; Bergeron, Sophie; Pukall, Caroline F; Khalifé, Samir
2016-06-01
Provoked vestibulodynia (PVD) is suspected to be the most frequent cause of vulvodynia in premenopausal women. Previous research has been inconclusive as to whether higher vulvovaginal pain ratings are associated with lower sexual function and satisfaction in women with PVD. Whether pain intensity correlates with sexual impairment is an important question given its implications for treatment recommendations. To examine the associations among self-reported and objective pain measurements, sexual function, and sexual satisfaction in a large combined clinical and community sample of premenopausal women diagnosed with PVD. Ninety-eight women with PVD underwent a cotton-swab test, a vestibular friction pain measurement, and a vestibular pressure-pain threshold measurement. In addition to sociodemographics, participants completed measurements of pain, sexual function, and sexual satisfaction. Self-report measurements were the pain numerical rating scale (0-10), the McGill-Melzack Pain Questionnaire, the Female Sexual Function Index, and the Global Measure of Sexual Satisfaction. Objective measurements were pain during a cotton-swab test, pain during a vestibular friction procedure, and the vestibular pressure-pain threshold measurement. Age and relationship duration were significantly correlated with the Female Sexual Function Index total score (r = -0.31, P < .01; and r = -0.22, P < .05, respectively). When controlling for age, intercourse-related pain intensity, pain during the cotton-swab test, pain during vestibular friction, the vestibular pressure-pain threshold, and the McGill-Melzack Pain Questionnaire sensory and affective subscale scores were not significantly associated with sexual function and satisfaction in women with PVD. The findings show that in women with PVD, self-report and objective pain ratings are not associated with sexual function and satisfaction. The results support the biopsychosocial nature of PVD and underscore the importance of a patient-focused multidisciplinary treatment approach for PVD. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Culture, Communication, and the Challenge of Globalization.
ERIC Educational Resources Information Center
Shome, Raka; Hegde, Radha S.
2002-01-01
Deals with the problematics that globalization poses for critical communication scholarship. Address how uneven patterns of global processes are enacted through cultural practices produced by the transnational flows of images and capital. Explores several areas of contemporary global growth with the overall objective of demonstrating the urgency…
Surrogate-based Analysis and Optimization
NASA Technical Reports Server (NTRS)
Queipo, Nestor V.; Haftka, Raphael T.; Shyy, Wei; Goel, Tushar; Vaidyanathan, Raj; Tucker, P. Kevin
2005-01-01
A major challenge to the successful full-scale development of modem aerospace systems is to address competing objectives such as improved performance, reduced costs, and enhanced safety. Accurate, high-fidelity models are typically time consuming and computationally expensive. Furthermore, informed decisions should be made with an understanding of the impact (global sensitivity) of the design variables on the different objectives. In this context, the so-called surrogate-based approach for analysis and optimization can play a very valuable role. The surrogates are constructed using data drawn from high-fidelity models, and provide fast approximations of the objectives and constraints at new design points, thereby making sensitivity and optimization studies feasible. This paper provides a comprehensive discussion of the fundamental issues that arise in surrogate-based analysis and optimization (SBAO), highlighting concepts, methods, techniques, as well as practical implications. The issues addressed include the selection of the loss function and regularization criteria for constructing the surrogates, design of experiments, surrogate selection and construction, sensitivity analysis, convergence, and optimization. The multi-objective optimal design of a liquid rocket injector is presented to highlight the state of the art and to help guide future efforts.
Object attributes combine additively in visual search.
Pramod, R T; Arun, S P
2016-01-01
We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes.
Du, Shaoyi; Xu, Yiting; Wan, Teng; Hu, Huaizhong; Zhang, Sirui; Xu, Guanglin; Zhang, Xuetao
2017-01-01
The iterative closest point (ICP) algorithm is efficient and accurate for rigid registration but it needs the good initial parameters. It is easily failed when the rotation angle between two point sets is large. To deal with this problem, a new objective function is proposed by introducing a rotation invariant feature based on the Euclidean distance between each point and a global reference point, where the global reference point is a rotation invariant. After that, this optimization problem is solved by a variant of ICP algorithm, which is an iterative method. Firstly, the accurate correspondence is established by using the weighted rotation invariant feature distance and position distance together. Secondly, the rigid transformation is solved by the singular value decomposition method. Thirdly, the weight is adjusted to control the relative contribution of the positions and features. Finally this new algorithm accomplishes the registration by a coarse-to-fine way whatever the initial rotation angle is, which is demonstrated to converge monotonically. The experimental results validate that the proposed algorithm is more accurate and robust compared with the original ICP algorithm.
Du, Shaoyi; Xu, Yiting; Wan, Teng; Zhang, Sirui; Xu, Guanglin; Zhang, Xuetao
2017-01-01
The iterative closest point (ICP) algorithm is efficient and accurate for rigid registration but it needs the good initial parameters. It is easily failed when the rotation angle between two point sets is large. To deal with this problem, a new objective function is proposed by introducing a rotation invariant feature based on the Euclidean distance between each point and a global reference point, where the global reference point is a rotation invariant. After that, this optimization problem is solved by a variant of ICP algorithm, which is an iterative method. Firstly, the accurate correspondence is established by using the weighted rotation invariant feature distance and position distance together. Secondly, the rigid transformation is solved by the singular value decomposition method. Thirdly, the weight is adjusted to control the relative contribution of the positions and features. Finally this new algorithm accomplishes the registration by a coarse-to-fine way whatever the initial rotation angle is, which is demonstrated to converge monotonically. The experimental results validate that the proposed algorithm is more accurate and robust compared with the original ICP algorithm. PMID:29176780
The future of spaceborne altimetry. Oceans and climate change: A long-term strategy
NASA Technical Reports Server (NTRS)
Koblinsky, C. J. (Editor); Gaspar, P. (Editor); Lagerloef, G. (Editor)
1992-01-01
The ocean circulation and polar ice sheet volumes provide important memory and control functions in the global climate. Their long term variations are unknown and need to be understood before meaningful appraisals of climate change can be made. Satellite altimetry is the only method for providing global information on the ocean circulation and ice sheet volume. A robust altimeter measurement program is planned which will initiate global observations of the ocean circulation and polar ice sheets. In order to provide useful data about the climate, these measurements must be continued with unbroken coverage into the next century. Herein, past results of the role of the ocean in the climate system is summarized, near term goals are outlined, and requirements and options are presented for future altimeter missions. There are three basic scientific objectives for the program: ocean circulation; polar ice sheets; and mean sea level change. The greatest scientific benefit will be achieved with a series of dedicated high precision altimeter spacecraft, for which the choice of orbit parameters and system accuracy are unencumbered by requirements of companion instruments.
Increased Global Interaction Across Functional Brain Modules During Cognitive Emotion Regulation.
Brandl, Felix; Mulej Bratec, Satja; Xie, Xiyao; Wohlschläger, Afra M; Riedl, Valentin; Meng, Chun; Sorg, Christian
2017-07-13
Cognitive emotion regulation (CER) enables humans to flexibly modulate their emotions. While local theories of CER neurobiology suggest interactions between specialized local brain circuits underlying CER, e.g., in subparts of amygdala and medial prefrontal cortices (mPFC), global theories hypothesize global interaction increases among larger functional brain modules comprising local circuits. We tested the global CER hypothesis using graph-based whole-brain network analysis of functional MRI data during aversive emotional processing with and without CER. During CER, global between-module interaction across stable functional network modules increased. Global interaction increase was particularly driven by subregions of amygdala and cuneus-nodes of highest nodal participation-that overlapped with CER-specific local activations, and by mPFC and posterior cingulate as relevant connector hubs. Results provide evidence for the global nature of human CER, complementing functional specialization of embedded local brain circuits during successful CER. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Sass, Hjalte C R; Borup, Rehannah; Alanin, Mikkel; Nielsen, Finn Cilius; Cayé-Thomasen, Per
2017-01-01
The objective of this study was to determine global gene expression in relation to Vestibular schwannomas (VS) growth rate and to identify signal transduction pathways and functional molecular networks associated with growth. Repeated magnetic resonance imaging (MRI) prior to surgery determined tumor growth rate. Following tissue sampling during surgery, mRNA was extracted from 16 sporadic VS. Double stranded cDNA was synthesized from the mRNA and used as template for in vitro transcription reaction to synthesize biotin-labeled antisense cRNA, which was hybridized to Affymetrix HG-U133A arrays and analyzed by dChip software. Differential gene expression was defined as a 1.5-fold difference between fast and slow growing tumors (><0.5 ccm/year), employing a p-value <0.01. Deregulated transcripts were matched against established gene ontology. Ingenuity Pathway Analysis was used for identification of signal transduction pathways and functional molecular networks associated with tumor growth. In total 109 genes were deregulated in relation to tumor growth rate. Genes associated with apoptosis, growth and cell proliferation were deregulated. Gene ontology included regulation of the cell cycle, cell differentiation and proliferation, among other functions. Fourteen pathways were associated with tumor growth. Five functional molecular networks were generated. This first study on global gene expression in relation to vestibular schwannoma growth rate identified several genes, signal transduction pathways and functional networks associated with tumor progression. Specific genes involved in apoptosis, cell growth and proliferation were deregulated in fast growing tumors. Fourteen pathways were associated with tumor growth. Generated functional networks underlined the importance of the PI3K family, among others.
Hickler, Benjamin; MacDonald, Noni E; Senouci, Kamel; Schuh, Holly B
2017-06-16
The Second Strategic Objective of the Global Vaccine Action Plan, "individuals and communities understand the value of vaccines and demand immunization as both their right and responsibility", differs from the other five in that it does not focus on supply-side aspects of immunization programs but rather on public demand for vaccines and immunization services. This commentary summarizes the work (literature review, consultations with experts, and with potential users) and findings of the UNICEF/World Health Organization Strategic Objective 2 informal Working Group on Vaccine Demand, which developed a definition for demand and indicators related to Strategic Objective 2. Demand for vaccines and vaccination is a complex concept that is not external to supply systems but rather encompasses the interaction between human behaviors and system structure and dynamics. Copyright © 2017. Published by Elsevier Ltd.
Unsupervised Detection of Planetary Craters by a Marked Point Process
NASA Technical Reports Server (NTRS)
Troglio, G.; Benediktsson, J. A.; Le Moigne, J.; Moser, G.; Serpico, S. B.
2011-01-01
With the launch of several planetary missions in the last decade, a large amount of planetary images is being acquired. Preferably, automatic and robust processing techniques need to be used for data analysis because of the huge amount of the acquired data. Here, the aim is to achieve a robust and general methodology for crater detection. A novel technique based on a marked point process is proposed. First, the contours in the image are extracted. The object boundaries are modeled as a configuration of an unknown number of random ellipses, i.e., the contour image is considered as a realization of a marked point process. Then, an energy function is defined, containing both an a priori energy and a likelihood term. The global minimum of this function is estimated by using reversible jump Monte-Carlo Markov chain dynamics and a simulated annealing scheme. The main idea behind marked point processes is to model objects within a stochastic framework: Marked point processes represent a very promising current approach in the stochastic image modeling and provide a powerful and methodologically rigorous framework to efficiently map and detect objects and structures in an image with an excellent robustness to noise. The proposed method for crater detection has several feasible applications. One such application area is image registration by matching the extracted features.
Simultaneous Detection and Tracking of Pedestrian from Panoramic Laser Scanning Data
NASA Astrophysics Data System (ADS)
Xiao, Wen; Vallet, Bruno; Schindler, Konrad; Paparoditis, Nicolas
2016-06-01
Pedestrian traffic flow estimation is essential for public place design and construction planning. Traditional data collection by human investigation is tedious, inefficient and expensive. Panoramic laser scanners, e.g. Velodyne HDL-64E, which scan surroundings repetitively at a high frequency, have been increasingly used for 3D object tracking. In this paper, a simultaneous detection and tracking (SDAT) method is proposed for precise and automatic pedestrian trajectory recovery. First, the dynamic environment is detected using two different methods, Nearest-point and Max-distance. Then, all the points on moving objects are transferred into a space-time (x, y, t) coordinate system. The pedestrian detection and tracking amounts to assign the points belonging to pedestrians into continuous trajectories in space-time. We formulate the point assignment task as an energy function which incorporates the point evidence, trajectory number, pedestrian shape and motion. A low energy trajectory will well explain the point observations, and have plausible trajectory trend and length. The method inherently filters out points from other moving objects and false detections. The energy function is solved by a two-step optimization process: tracklet detection in a short temporal window; and global tracklet association through the whole time span. Results demonstrate that the proposed method can automatically recover the pedestrians trajectories with accurate positions and low false detections and mismatches.
Automated Calibration For Numerical Models Of Riverflow
NASA Astrophysics Data System (ADS)
Fernandez, Betsaida; Kopmann, Rebekka; Oladyshkin, Sergey
2017-04-01
Calibration of numerical models is fundamental since the beginning of all types of hydro system modeling, to approximate the parameters that can mimic the overall system behavior. Thus, an assessment of different deterministic and stochastic optimization methods is undertaken to compare their robustness, computational feasibility, and global search capacity. Also, the uncertainty of the most suitable methods is analyzed. These optimization methods minimize the objective function that comprises synthetic measurements and simulated data. Synthetic measurement data replace the observed data set to guarantee an existing parameter solution. The input data for the objective function derivate from a hydro-morphological dynamics numerical model which represents an 180-degree bend channel. The hydro- morphological numerical model shows a high level of ill-posedness in the mathematical problem. The minimization of the objective function by different candidate methods for optimization indicates a failure in some of the gradient-based methods as Newton Conjugated and BFGS. Others reveal partial convergence, such as Nelder-Mead, Polak und Ribieri, L-BFGS-B, Truncated Newton Conjugated, and Trust-Region Newton Conjugated Gradient. Further ones indicate parameter solutions that range outside the physical limits, such as Levenberg-Marquardt and LeastSquareRoot. Moreover, there is a significant computational demand for genetic optimization methods, such as Differential Evolution and Basin-Hopping, as well as for Brute Force methods. The Deterministic Sequential Least Square Programming and the scholastic Bayes Inference theory methods present the optimal optimization results. keywords: Automated calibration of hydro-morphological dynamic numerical model, Bayesian inference theory, deterministic optimization methods.
NASA Astrophysics Data System (ADS)
Wang, Zuo-Cai; Xin, Yu; Ren, Wei-Xin
2016-08-01
This paper proposes a new nonlinear joint model updating method for shear type structures based on the instantaneous characteristics of the decomposed structural dynamic responses. To obtain an accurate representation of a nonlinear system's dynamics, the nonlinear joint model is described as the nonlinear spring element with bilinear stiffness. The instantaneous frequencies and amplitudes of the decomposed mono-component are first extracted by the analytical mode decomposition (AMD) method. Then, an objective function based on the residuals of the instantaneous frequencies and amplitudes between the experimental structure and the nonlinear model is created for the nonlinear joint model updating. The optimal values of the nonlinear joint model parameters are obtained by minimizing the objective function using the simulated annealing global optimization method. To validate the effectiveness of the proposed method, a single-story shear type structure subjected to earthquake and harmonic excitations is simulated as a numerical example. Then, a beam structure with multiple local nonlinear elements subjected to earthquake excitation is also simulated. The nonlinear beam structure is updated based on the global and local model using the proposed method. The results show that the proposed local nonlinear model updating method is more effective for structures with multiple local nonlinear elements. Finally, the proposed method is verified by the shake table test of a real high voltage switch structure. The accuracy of the proposed method is quantified both in numerical and experimental applications using the defined error indices. Both the numerical and experimental results have shown that the proposed method can effectively update the nonlinear joint model.
Werner, Kimberly B; Griffin, Michael G; Galovski, Tara E
2016-06-30
Sleep disturbance may be the most often endorsed symptom of posttraumatic stress disorder (PTSD). Much of this research is based on subjective reports from trauma survivors; however, objective measures of sleep-related impairment have yielded findings inconsistent with self-report data. More studies investigating subjective and objective assessments concordantly are needed to understand sleep impairment in PTSD. The current study examined PTSD-related sleep disturbance in a female interpersonal violence cohort with full PTSD diagnoses (N=51) assessing subjective (global and daily diary measures) and objective (actigraphy) sleep measures concurrently. PTSD severity was positively associated with global, subjective reports of sleep impairment and insomnia. Subjective measures of sleep (including global sleep impairment, insomnia, and daily sleep diary reports of total sleep time, sleep efficiency, and sleep onset latency) were moderately to strongly correlated. However, no significant correlations between subjective and objective reports of sleep impairment were found in this cohort. Analyses demonstrated an overall elevation in subjectively reported sleep impairment when compared to objective measurement assessed concurrently. Findings demonstrate a lack of agreement between subjective and objective measurements of sleep in a PTSD-positive female cohort, suggesting objective and subjective sleep impairments are distinct sleep parameters that do not necessarily directly co-vary. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Knapp, Julia L. A.; Cirpka, Olaf A.
2017-06-01
The complexity of hyporheic flow paths requires reach-scale models of solute transport in streams that are flexible in their representation of the hyporheic passage. We use a model that couples advective-dispersive in-stream transport to hyporheic exchange with a shape-free distribution of hyporheic travel times. The model also accounts for two-site sorption and transformation of reactive solutes. The coefficients of the model are determined by fitting concurrent stream-tracer tests of conservative (fluorescein) and reactive (resazurin/resorufin) compounds. The flexibility of the shape-free models give rise to multiple local minima of the objective function in parameter estimation, thus requiring global-search algorithms, which is hindered by the large number of parameter values to be estimated. We present a local-in-global optimization approach, in which we use a Markov-Chain Monte Carlo method as global-search method to estimate a set of in-stream and hyporheic parameters. Nested therein, we infer the shape-free distribution of hyporheic travel times by a local Gauss-Newton method. The overall approach is independent of the initial guess and provides the joint posterior distribution of all parameters. We apply the described local-in-global optimization method to recorded tracer breakthrough curves of three consecutive stream sections, and infer section-wise hydraulic parameter distributions to analyze how hyporheic exchange processes differ between the stream sections.
Manne, Sharon; Badr, Hoda
2009-01-01
Objective Couples coping with head and neck and lung cancers are at increased risk for psychological and relationship distress given patients’ poor prognosis and aggressive and sometimes disfiguring treatments. The relationship intimacy model of couples’ psychosocial adaptation proposes that relationship intimacy mediates associations between couples’ cancer-related support communication and psychological distress. Because the components of this model have not yet been evaluated in the same study, we examined associations between three types of cancer-related support communication (self-disclosure, perceived partner disclosure, and protective buffering), intimacy (global and cancer-specific), and global distress among patients coping with either head and neck or lung cancer and their partners. Method One hundred and nine patients undergoing active treatment and their partners whose average time since diagnosis was 15 months completed cross-sectional surveys. Results For both patients and their partners, multilevel analyses using the Actor-Partner Interdependence Model showed that global and cancer-specific intimacy fully mediated associations between self- and perceived partner disclosure and distress; global intimacy partially mediated the association between protective buffering and distress. Evidence for moderated mediation was found; specifically, lower levels of distress were reported as a function of global and cancer-specific intimacy, but these associations were stronger for partners than for patients. Conclusions Enhancing relationship intimacy by disclosing cancer-related concerns may facilitate both partners’ adjustment to these illnesses. PMID:19885852
ERIC Educational Resources Information Center
Tomlinson, M.; Yasamy, M. T.; Emerson, E.; Officer, A.; Richler, D.; Saxena, S.
2014-01-01
Objectives: The prevalence of intellectual disabilities (ID) has been estimated at 10.4/1000 worldwide with higher rates among children and adolescents in lower income countries. The objective of this paper is to address research priorities for development disabilities, notably ID and autism, at the global level and to propose the more rational…
Garbage Collection in a Distributed Object-Oriented System
NASA Technical Reports Server (NTRS)
Gupta, Aloke; Fuchs, W. Kent
1993-01-01
An algorithm is described in this paper for garbage collection in distributed systems with object sharing across processor boundaries. The algorithm allows local garbage collection at each node in the system to proceed independently of local collection at the other nodes. It requires no global synchronization or knowledge of the global state of the system and exhibits the capability of graceful degradation. The concept of a specialized dump node is proposed to facilitate the collection of inaccessible circular structures. An experimental evaluation of the algorithm is also described. The algorithm is compared with a corresponding scheme that requires global synchronization. The results show that the algorithm works well in distributed processing environments even when the locality of object references is low.
A Regions of Confidence Based Approach to Enhance Segmentation with Shape Priors.
Appia, Vikram V; Ganapathy, Balaji; Abufadel, Amer; Yezzi, Anthony; Faber, Tracy
2010-01-18
We propose an improved region based segmentation model with shape priors that uses labels of confidence/interest to exclude the influence of certain regions in the image that may not provide useful information for segmentation. These could be regions in the image which are expected to have weak, missing or corrupt edges or they could be regions in the image which the user is not interested in segmenting, but are part of the object being segmented. In the training datasets, along with the manual segmentations we also generate an auxiliary map indicating these regions of low confidence/interest. Since, all the training images are acquired under similar conditions, we can train our algorithm to estimate these regions as well. Based on this training we will generate a map which indicates the regions in the image that are likely to contain no useful information for segmentation. We then use a parametric model to represent the segmenting curve as a combination of shape priors obtained by representing the training data as a collection of signed distance functions. We evolve an objective energy functional to evolve the global parameters that are used to represent the curve. We vary the influence each pixel has on the evolution of these parameters based on the confidence/interest label. When we use these labels to indicate the regions with low confidence; the regions containing accurate edges will have a dominant role in the evolution of the curve and the segmentation in the low confidence regions will be approximated based on the training data. Since our model evolves global parameters, it improves the segmentation even in the regions with accurate edges. This is because we eliminate the influence of the low confidence regions which may mislead the final segmentation. Similarly when we use the labels to indicate the regions which are not of importance, we will get a better segmentation of the object in the regions we are interested in.
Engineering calculations for communications satellite systems planning
NASA Technical Reports Server (NTRS)
Reilly, C. H.; Levis, C. A.; Mount-Campbell, C.; Gonsalvez, D. J.; Wang, C. W.; Yamamura, Y.
1985-01-01
Computer-based techniques for optimizing communications-satellite orbit and frequency assignments are discussed. A gradient-search code was tested against a BSS scenario derived from the RARC-83 data. Improvement was obtained, but each iteration requires about 50 minutes of IBM-3081 CPU time. Gradient-search experiments on a small FSS test problem, consisting of a single service area served by 8 satellites, showed quickest convergence when the satellites were all initially placed near the center of the available orbital arc with moderate spacing. A transformation technique is proposed for investigating the surface topography of the objective function used in the gradient-search method. A new synthesis approach is based on transforming single-entry interference constraints into corresponding constraints on satellite spacings. These constraints are used with linear objective functions to formulate the co-channel orbital assignment task as a linear-programming (LP) problem or mixed integer programming (MIP) problem. Globally optimal solutions are always found with the MIP problems, but not necessarily with the LP problems. The MIP solutions can be used to evaluate the quality of the LP solutions. The initial results are very encouraging.
A new memetic algorithm for mitigating tandem automated guided vehicle system partitioning problem
NASA Astrophysics Data System (ADS)
Pourrahimian, Parinaz
2017-11-01
Automated Guided Vehicle System (AGVS) provides the flexibility and automation demanded by Flexible Manufacturing System (FMS). However, with the growing concern on responsible management of resource use, it is crucial to manage these vehicles in an efficient way in order reduces travel time and controls conflicts and congestions. This paper presents the development process of a new Memetic Algorithm (MA) for optimizing partitioning problem of tandem AGVS. MAs employ a Genetic Algorithm (GA), as a global search, and apply a local search to bring the solutions to a local optimum point. A new Tabu Search (TS) has been developed and combined with a GA to refine the newly generated individuals by GA. The aim of the proposed algorithm is to minimize the maximum workload of the system. After all, the performance of the proposed algorithm is evaluated using Matlab. This study also compared the objective function of the proposed MA with GA. The results showed that the TS, as a local search, significantly improves the objective function of the GA for different system sizes with large and small numbers of zone by 1.26 in average.
NASA Technical Reports Server (NTRS)
Riley, Gary
1991-01-01
The C Language Integrated Production System (CLIPS) is a forward chaining rule based language developed by NASA. CLIPS was designed specifically to provide high portability, low cost, and easy integration with external systems. The current release of CLIPS, version 4.3, is being used by over 2500 users throughout the public and private community. The primary addition to the next release of CLIPS, version 5.0, will be the CLIPS Object Oriented Language (COOL). The major capabilities of COOL are: class definition with multiple inheritance and no restrictions on the number, types, or cardinality of slots; message passing which allows procedural code bundled with an object to be executed; and query functions which allow groups of instances to be examined and manipulated. In addition to COOL, numerous other enhancements were added to CLIPS including: generic functions (which allow different pieces of procedural code to be executed depending upon the types or classes of the arguments); integer and double precision data type support; multiple conflict resolution strategies; global variables; logical dependencies; type checking on facts; full ANSI compiler support; and incremental reset for rules.
Pareto-Optimal Estimates of California Precipitation Change
NASA Astrophysics Data System (ADS)
Langenbrunner, Baird; Neelin, J. David
2017-12-01
In seeking constraints on global climate model projections under global warming, one commonly finds that different subsets of models perform well under different objective functions, and these trade-offs are difficult to weigh. Here a multiobjective approach is applied to a large set of subensembles generated from the Climate Model Intercomparison Project phase 5 ensemble. We use observations and reanalyses to constrain tropical Pacific sea surface temperatures, upper level zonal winds in the midlatitude Pacific, and California precipitation. An evolutionary algorithm identifies the set of Pareto-optimal subensembles across these three measures, and these subensembles are used to constrain end-of-century California wet season precipitation change. This methodology narrows the range of projections throughout California, increasing confidence in estimates of positive mean precipitation change. Finally, we show how this technique complements and generalizes emergent constraint approaches for restricting uncertainty in end-of-century projections within multimodel ensembles using multiple criteria for observational constraints.
Characterization and control of self-motions in redundant manipulators
NASA Technical Reports Server (NTRS)
Burdick, J.; Seraji, Homayoun
1989-01-01
The presence of redundant degrees of freedom in a manipulator structure leads to a physical phenomenon known as a self-motion, which is a continuous motion of the manipulator joints that leaves the end-effector motionless. In the first part of the paper, a global manifold mapping reformulation of manipulator kinematics is reviewed, and the inverse kinematic solution for redundant manipulators is developed in terms of self-motion manifolds. Global characterizations of the self-motion manifolds in terms of their number, geometry, homotopy class, and null space are reviewed using examples. Much previous work in redundant manipulator control has been concerned with the redundancy resolution problem, in which methods are developed to determine, or resolve, the motion of the joints in order to achieve end-effector trajectory control while optimizing additional objective functions. Redundancy resolution problems can be equivalently posed as the control of self-motions. Alternatives for redundancy resolution are briefly discussed.
McFadden, Brandon R
2016-01-01
There is great uncertainty due to challenges of escalating population growth and climate change. Public perception that diverges from the scientific community may decrease the effectiveness of scientific inquiry and innovation as tools to solve these challenges. The objective of this study was to identify the factors associated with the divergence of public opinion from scientific consensus regarding the safety of genetically modified (GM) foods and human involvement in global warming (GW). Results indicate that the effects of knowledge on public opinion are complex and non-uniform across types of knowledge (i.e., perceived and actual) or issues. Political affiliation affects agreement with science; Democrats were more likely to agree that GM food is safe and human actions cause GW. Respondents who had relatively higher cognitive function or held illusionary correlations about GM food or GW were more likely to have an opinion that differed from the scientific community.
McFadden, Brandon R.
2016-01-01
There is great uncertainty due to challenges of escalating population growth and climate change. Public perception that diverges from the scientific community may decrease the effectiveness of scientific inquiry and innovation as tools to solve these challenges. The objective of this study was to identify the factors associated with the divergence of public opinion from scientific consensus regarding the safety of genetically modified (GM) foods and human involvement in global warming (GW). Results indicate that the effects of knowledge on public opinion are complex and non-uniform across types of knowledge (i.e., perceived and actual) or issues. Political affiliation affects agreement with science; Democrats were more likely to agree that GM food is safe and human actions cause GW. Respondents who had relatively higher cognitive function or held illusionary correlations about GM food or GW were more likely to have an opinion that differed from the scientific community. PMID:27829008
A global design of high power Nd 3+-Yb 3+ co-doped fiber lasers
NASA Astrophysics Data System (ADS)
Fan, Zhang; Chuncan, Wang; Tigang, Ning
2008-09-01
A global optimization method - niche hybrid genetic algorithm (NHGA) based on fitness sharing and elite replacement is applied to optimize Nd3+-Yb3+ co-doped fiber lasers (NYDFLs) for obtaining maximum signal output power. With a objective function and different pumping powers, five critical parameters (the fiber length, L; the proportion of pump power for pumping Nd3+, η; Nd3+ and Yb3+ concentrations, NNd and NYb and output mirror reflectivity, Rout) of the given NYDFLs are optimized by solving the rate and power propagation equations. Results show that dividing equally the input pump power among 808 nm (Nd3+) and 940 nm (Yb3+) is not an optimal choice and the pump power of Nd3+ ions should be kept around 10-13.78% of the total pump power. Three optimal schemes are obtained by NHGA and the highest slope efficiency of the laser is able to reach 80.1%.
Lindfors, Olavi; Knekt, Paul; Heinonen, Erkki; Virtala, Esa
2014-01-01
Quality of object relations and self-concept reflect clinically relevant aspects of personality functioning, but their prediction as suitability factors for psychotherapies of different lengths has not been compared. This study compared their prediction on psychiatric symptoms and work ability in short- and long-term psychotherapy. Altogether 326 patients, 20-46 years of age, with mood and/or anxiety disorder, were randomized to short-term (solution-focused or short-term psychodynamic) psychotherapy and long-term psychodynamic psychotherapy. The Quality of Object Relations Scale (QORS) and the Structural Analysis of Social Behavior (SASB) self-concept questionnaire were measured at baseline, and their prediction on outcome during the 3-year follow-up was assessed by the Symptom Check List Global Severity Index and the Anxiety Scale, the Beck Depression Inventory and by the Work Ability Index, Social Adjustment Scale work subscale and the Perceived Psychological Functioning scale. Negative self-concept strongly and self-controlling characteristics modestly predicted better 3-year outcomes in long-term therapy, after faster early gains in short-term therapy. Patients with a more positive or self-emancipating self-concept, or more mature object relations, experienced more extensive benefits after long-term psychotherapy. The importance of length vs. long-term therapy technique on the differences found is not known. Patients with mild to moderate personality pathology, indicated by poor self-concept, seem to benefit more from long-term than short-term psychotherapy, in reducing risk of depression. Long-term therapy may also be indicated for patients with relatively good psychological functioning. More research is needed on the relative importance of these characteristics in comparison with other patient-related factors. © 2013 Published by Elsevier B.V.
Defining Health Diplomacy: Changing Demands in the Era of Globalization
Katz, Rebecca; Kornblet, Sarah; Arnold, Grace; Lief, Eric; Fischer, Julie E
2011-01-01
Context: Accelerated globalization has produced obvious changes in diplomatic purposes and practices. Health issues have become increasingly preeminent in the evolving global diplomacy agenda. More leaders in academia and policy are thinking about how to structure and utilize diplomacy in pursuit of global health goals. Methods: In this article, we describe the context, practice, and components of global health diplomacy, as applied operationally. We examine the foundations of various approaches to global health diplomacy, along with their implications for the policies shaping the international public health and foreign policy environments. Based on these observations, we propose a taxonomy for the subdiscipline. Findings: Expanding demands on global health diplomacy require a delicate combination of technical expertise, legal knowledge, and diplomatic skills that have not been systematically cultivated among either foreign service or global health professionals. Nonetheless, high expectations that global health initiatives will achieve development and diplomatic goals beyond the immediate technical objectives may be thwarted by this gap. Conclusions: The deepening links between health and foreign policy require both the diplomatic and global health communities to reexamine the skills, comprehension, and resources necessary to achieve their mutual objectives. PMID:21933277
World Health Organization and disease surveillance: Jeopardizing global public health?
Blouin Genest, Gabriel
2015-11-01
Health issues now evolve in a global context. Real-time global surveillance, global disease mapping and global risk management characterize what have been termed 'global public health'. It has generated many programmes and policies, notably through the work of the World Health Organization. This globalized form of public health raises, however, some important issues left unchallenged, including its effectiveness, objectivity and legitimacy. The general objective of this article is to underline the impacts of WHO disease surveillance on the practice and theorization of global public health. By using the surveillance structure established by the World Health Organization and reinforced by the 2005 International Health Regulations as a case study, we argue that the policing of 'circulating risks' emerged as a dramatic paradox for global public health policy. This situation severely affects the rationale of health interventions as well as the lives of millions around the world, while travestying the meaning of health, disease and risks. To do so, we use health surveillance data collected by the WHO Disease Outbreak News System in order to map the impacts of global health surveillance on health policy rationale and theory. © The Author(s) 2014.
Cognitive Performance in Suicidal Depressed Elderly: Preliminary Report
Dombrovski, Alexandre Y.; Butters, Meryl A.; Reynolds, Charles F.; Houck, Patricia R.; Clark, Luke; Mazumdar, Sati; Szanto, Katalin
2009-01-01
Objective Deficits in executive functions may play an important role in late-life suicide; however the association is understudied. This study examined cognitive function in general and executive functioning specifically in depressed elderly with and without suicidal ideation and attempts. Design Case-control study. Setting University-affiliated psychiatric hospital. Participants We compared 32 suicidal depressed participants aged 60 and older with 32 non-suicidal depressed participants equated for age, education, and gender. Measurements We assessed global cognitive function and executive function with the Dementia Rating Scale (DRS) and the Executive Interview (EXIT25), respectively. Results Suicidal and non-suicidal depressed groups were comparable in terms of severity of depression and burden of physical illness. Suicidal participants performed worse on the EXIT25, and on the DRS total scale, as well as on Memory and Attention subscales. The differences were not explained by the presence of dementia, substance use, medication exposure, or brain injury from suicide attempts. Conclusions Poor performance on tests of executive function, attention, and memory is associated with suicidal behavior in late-life depression. PMID:18239196
Coastline complexity: A parameter for functional classification of coastal environments
Bartley, J.D.; Buddemeier, R.W.; Bennett, D.A.
2001-01-01
To understand the role of the world's coastal zone (CZ) in global biogeochemical fluxes (particularly those of carbon, nitrogen, phosphorus, and sediments) we must generalise from a limited number of observations associated with a few well-studied coastal systems to the global scale. Global generalisation must be based on globally available data and on robust techniques for classification and upscaling. These requirements impose severe constraints on the set of variables that can be used to extract information about local CZ functions such as advective and metabolic fluxes, and differences resulting from changes in biotic communities. Coastal complexity (plan-view tortuosity of the coastline) is a potentially useful parameter, since it interacts strongly with both marine and terrestrial forcing functions to determine coastal energy regimes and water residence times, and since 'open' vs. 'sheltered' categories are important components of most coastal habitat classification schemes. This study employs the World Vector Shoreline (WVS) dataset, originally developed at a scale of 1:250 000. Coastline complexity measures are generated using a modification of the Angle Measurement Technique (AMT), in which the basic measurement is the angle between two lines of specified length drawn from a selected point to the closest points of intersection with the coastline. Repetition of these measurements for different lengths at the same point yields a distribution of angles descriptive of the extent and scale of complexity in the vicinity of that point; repetition of the process at different points on the coast provides a basis for comparing both the extent and the characteristic scale of coastline variation along different reaches of the coast. The coast of northwestern Mexico (Baja California and the Gulf of California) was used as a case study for initial development and testing of the method. The characteristic angle distribution plots generated by the AMT analysis were clustered using LOICZVIEW, a high dimensionality clustering routine developed for large-scale coastal classification studies. The results show distinctive differences in coastal environments that have the potential for interpretation in terms of both biotic and hydrogeochemical environments, and that can be related to the resolution limits and uncertainties of the shoreline data used. These objective, quantitative measures of coastal complexity as a function of scale can be further developed and combined with other data sets to provide a key component of functional classification of coastal environments. ?? 2001 Elsevier Science B.V. All rights reserved.
Six-year follow-up of the treatment of patients with dissociative disorders study.
Myrick, Amie C; Webermann, Aliya R; Loewenstein, Richard J; Lanius, Ruth; Putnam, Frank W; Brand, Bethany L
2017-01-01
Objective : Literature on the treatment of dissociative disorders (DDs) suggests that these individuals require long-term and specialized treatment to achieve stabilization and functionality. There is considerable empirical support for specialized phasic, dissociation-focused treatment in reducing a myriad of psychological symptoms and self-harm in this population. However, until recently, there has been a paucity of longitudinal treatment research on DD patients. Method : In the present six-year follow-up study, 61 therapists who participated in the initial phase of the Treatment of Patients with Dissociative Disorders (TOP DD) study answered questionnaires about their study patient's stressors, quality of life, global functioning, victimization, and safety. These results provided a view of patients' progress six years since the beginning of the TOP DD study. Results : Longitudinal analyses demonstrated patients had significantly fewer stressors ( Χ 2 (6) = 18.76, p < .01, canonical r = .48, N = 76), instances of sexual revictimization ( X 2 (1) = 107.05, p < .001) and psychiatric hospitalizations ( t (54) = 2.57, p < .05, Cohen's d = .43), as well as higher global functioning ( Χ 2 (2) = 59.27, p < .001, canonical r = .65, N = 111). Conclusions : These findings continue to support the initial results of the TOP DD study that, despite marked initial difficulties and functional impairment, DD patients benefit from specialized treatment.
NASA Astrophysics Data System (ADS)
Koon, D. W.; Knickerbocker, C. J.
1996-12-01
The effect of macroscopic inhomogeneities on resistivity and Hall angle measurements is studied by calculating weighting functions (the relative effect of perturbations in a local transport property on the measured global average for the object) for cross, cloverleaf, and bar-shaped geometries. The ``sweet spot,'' the region in the center of the object that the measurement effectively samples, is smaller for crosses and cloverleafs than for the circles and squares already studied, and smaller for the cloverleaf than for the corresponding cross. Resistivity measurements for crosses and cloverleafs suffer from singularities and negative weighting, which can be eliminated by averaging two independent resistance measurements, as done in the van der Pauw technique. Resistivity and Hall measurements made on sufficiently narrow bars are shown to effectively sample only the region directly between the voltage probes.
Behavior Disorders in Extremely Preterm/Extremely Low Birth Weight Children in Kindergarten
Scott, Megan N.; Taylor, H. Gerry; Fristad, Mary A.; Klein, Nancy; Espy, Kimberly Andrews; Minich, Nori; Hack, Maureen
2012-01-01
Objective To examine the prevalence of behavior disorders in a 2001–2003 birth cohort of extremely preterm/extremely low birth weight (EPT/ELBW, <28 weeks gestational age and/or <1000 g) children in kindergarten. Method We compared 148 EPT/ELBW children to 111 term-born normal birth weight (NBW) classmate controls on reports of psychiatric symptoms obtained from parent interview (P-ChIPS), parent and teacher ratings of behavior (CBCL, TRF, BRIEF), and teacher ratings of social functioning (SSBS-2). Associations of behavior disorders with global cognitive ability and tests of executive function were also examined within the EPT/ELBW group. Results Rates of ADHD Combined on psychiatric interview were about twice as high for the EPT/ELBW group than for the NBW group, OR (95% CI)=2.50 (1.34, 4.68), p=.004. The EPT/ELBW group also had much higher rates of teacher-identified disorders in attention, behavior self-regulation, and social functioning, with odds ratios (95% confidence intervals) ranging from 3.35 (1.64, 6.83) to 18.03 (4.12, 78.94), all p’s<.01. ADHD and impaired behavior self-regulation were associated with deficits on tests of executive function but not with global cognitive impairment. Conclusions The findings document elevated rates of disorders in attention, behavior self-regulation, and socialization in EPT/ELBW children and suggest that deficits on tests of executive function are associated with some of these disorders. Early identification and intervention for these disorders are needed to promote early adjustment to school and facilitate learning progress. PMID:22245934
Beaton, Andrea; Richards, Hedda; Ploutz, Michelle; Gaur, Lasya; Aliku, Twalib; Lwabi, Peter; Ensing, Greg; Sable, Craig
2017-08-01
Identification of patients with latent rheumatic heart disease by echocardiography presents a unique opportunity to prevent disease progression. Myocardial strain is a more sensitive indicator of cardiac performance than traditional measures of systolic function. The objective of this study was to test the hypothesis that abnormalities in myocardial strain may be present in children with latent rheumatic heart disease. Standard echocardiography images with electrocardiogram gating were obtained from Ugandan children found to have latent rheumatic heart disease as well as control subjects. Traditional echocardiography measures of systolic function were obtained, and offline global longitudinal strain analysis was performed. Comparison between groups was performed using strain as a continuous (Mann-Whitney U-test) and categorical (cut-off 5th percentile for age) variable. Our study included 14 subjects with definite rheumatic heart disease, 13 with borderline rheumatic heart disease, and 112 control subjects. None of the subjects had abnormal left ventricular size or ejection fraction. Global longitudinal strain was lower than the 5th percentile in 44% of the subjects with any rheumatic heart disease (p=0.002 versus controls) and 57% of the subjects with definite rheumatic heart disease (p=0.03). The mean absolute strain values were significantly lower when comparing subjects with any rheumatic heart disease with controls (20.4±3.95 versus 22.4±4.35, p=0.025) and subjects with definite rheumatic heart disease with controls (19.9±4.25 versus 22.4±4.35, p=0.033). Global longitudinal strain is decreased in subjects with rheumatic heart disease in the absence of abnormal systolic function. Larger studies with longer-term follow-up are required to determine whether there is a role for strain to help better understand the pathophysiology of latent rheumatic heart disease.
Object attributes combine additively in visual search
Pramod, R. T.; Arun, S. P.
2016-01-01
We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes. PMID:26967014
Geoffrion, Roxana; Hyakutake, Momoe T; Koenig, Nicole A; Lee, Terry; Cundiff, Geoffrey W
2015-02-01
Bilateral sacrospinous fixation with tailored mesh arms (bSSVF) uses polypropylene mesh to suspend the vault to the sacrospinous ligaments bilaterally with minimal tension, recreating nulliparous midline anatomy. It can be used with uterine conservation. Our primary objective was to determine objective cure rate at one year following bSSVF compared with a control group undergoing abdominal sacrocolpopexy (ASC). Secondary objectives were to compare symptoms, quality of life, sexual function, pain, and global satisfaction before and after surgery and between bSSVF and ASC groups at one year. This prospective cohort study enrolled patients with symptomatic prolapse who chose to undergo bSSVF or ASC. Baseline demographics were obtained. Prolapse quantification, validated symptom questionnaire scores, and McGill pain scores were obtained at baseline, six weeks, and one-year postoperatively. Global satisfaction was recorded. The primary outcome measure was the difference in cure rate (vault stage ≤ 1) between groups. Fifty patients were recruited: 30 underwent bSSVF and 17 ASC. Forty-three patients were available for one-year follow-up. Baseline data were similar. There was no difference in vault stage between bSSVF and ASC groups at one year. Five women who underwent bSSVF had cervical elongation, and four of these were classified as POP recurrence. Women who underwent bSSVF had more anterior recurrences but fewer postoperative complications, shorter hospital stay, and less use of narcotics than controls. Questionnaire scores were similar at one year. All respondents felt subjective improvement after either surgical procedure. Objective and subjective cure rates are comparable after bSSVF and ASC. Hysteropexy may cause cervical elongation that merits further research.
NoSOCS in SDSS - VI. The environmental dependence of AGN in clusters and field in the local Universe
NASA Astrophysics Data System (ADS)
Lopes, P. A. A.; Ribeiro, A. L. B.; Rembold, S. B.
2017-11-01
We investigated the variation in the fraction of optical active galactic nuclei (AGNs) hosts with stellar mass, as well as their local and global environments. Our sample is composed of cluster members and field galaxies at z ≤ 0.1 and we consider only strong AGN. We find a strong variation in the AGN fraction (FAGN) with stellar mass. The field population comprises a higher AGN fraction compared to the global cluster population, especially for objects with log M* > 10.6. Hence, we restricted our analysis to more massive objects. We detected a smooth variation in the FAGN with local stellar mass density for cluster objects, reaching a plateau in the field environment. As a function of cluster-centric distance we verify that FAGN is roughly constant for R > R200, but show a steep decline inwards. We have also verified the dependence of the AGN population on cluster velocity dispersion, finding a constant behaviour for low mass systems (σP ≲ 650-700 km s-1). However, there is a strong decline in FAGN for higher mass clusters (>700 km s-1). When comparing the FAGN in clusters with or without substructure, we only find different results for objects at large radii (R > R200), in the sense that clusters with substructure present some excess in the AGN fraction. Finally, we have found that the phase-space distribution of AGN cluster members is significantly different than other populations. Due to the environmental dependence of FAGN and their phase-space distribution, we interpret AGN to be the result of galaxy interactions, favoured in environments where the relative velocities are low, typical of the field, low mass groups or cluster outskirts.
A strategy to find minimal energy nanocluster structures.
Rogan, José; Varas, Alejandro; Valdivia, Juan Alejandro; Kiwi, Miguel
2013-11-05
An unbiased strategy to search for the global and local minimal energy structures of free standing nanoclusters is presented. Our objectives are twofold: to find a diverse set of low lying local minima, as well as the global minimum. To do so, we use massively the fast inertial relaxation engine algorithm as an efficient local minimizer. This procedure turns out to be quite efficient to reach the global minimum, and also most of the local minima. We test the method with the Lennard-Jones (LJ) potential, for which an abundant literature does exist, and obtain novel results, which include a new local minimum for LJ13 , 10 new local minima for LJ14 , and thousands of new local minima for 15≤N≤65. Insights on how to choose the initial configurations, analyzing the effectiveness of the method in reaching low-energy structures, including the global minimum, are developed as a function of the number of atoms of the cluster. Also, a novel characterization of the potential energy surface, analyzing properties of the local minima basins, is provided. The procedure constitutes a promising tool to generate a diverse set of cluster conformations, both two- and three-dimensional, that can be used as an input for refinement by means of ab initio methods. Copyright © 2013 Wiley Periodicals, Inc.
Emotional Intelligence Outcomes Regarding Empathy and Global Videoconferencing Lessons
ERIC Educational Resources Information Center
Pullen, Janet S.
2013-01-01
Students are participating in global education programs in schools today. The objectives for these global programs include preparing children intellectually and social-emotionally to be able to communicate and understand others from around the world, as well as encouraging children to develop a global view in their thinking about others in the…
The northern global change research program
Richard A. Birdsey; John L. Hom; Marla Emery
1996-01-01
The Forest Service goal for global change research is to establish a sound scientific basis for making regional, national, and international resource management and policy decisions in the context of global change issues. The objectives of the Northern Global Change Program (NGCP) are to understand: (1) what processes in forest ecosystems are sensitive to physical and...
ERIC Educational Resources Information Center
Reimers, Fernando
2006-01-01
One of the purposes of educational institutions is to develop citizenship. In the 21st century, citizenship includes global citizenship. Addressing the challenges of globalization will require making citizenship education and the development of global values an explicit objective of efforts to improve quality throughout the world, critically…
Opposite Cannabis-Cognition Associations in Psychotic Patients Depending on Family History.
González-Pinto, Ana; González-Ortega, Itxaso; Alberich, Susana; Ruiz de Azúa, Sonia; Bernardo, Miguel; Bioque, Miquel; Cabrera, Bibiana; Corripio, Iluminada; Arango, Celso; Lobo, Antonio; Sánchez-Torres, Ana M; Cuesta, Manuel J
2016-01-01
The objective of this study is to investigate cognitive performance in a first-episode psychosis sample, when stratifying the interaction by cannabis use and familial or non-familial psychosis. Hierarchical-regression models were used to analyse this association in a sample of 268 first-episode psychosis patients and 237 controls. We found that cannabis use was associated with worse working memory, regardless of family history. However, cannabis use was clearly associated with worse cognitive performance in patients with no family history of psychosis, in cognitive domains including verbal memory, executive function and global cognitive index, whereas cannabis users with a family history of psychosis performed better in these domains. The main finding of the study is that there is an interaction between cannabis use and a family history of psychosis in the areas of verbal memory, executive function and global cognition: that is, cannabis use is associated with a better performance in patients with a family history of psychosis and a worse performance in those with no family history of psychosis. In order to confirm this hypothesis, future research should explore the actual expression of the endocannabinoid system in patients with and without a family history of psychosis.
Opposite Cannabis-Cognition Associations in Psychotic Patients Depending on Family History
González-Pinto, Ana; González-Ortega, Itxaso; Alberich, Susana; Ruiz de Azúa, Sonia; Bernardo, Miguel; Bioque, Miquel; Cabrera, Bibiana; Corripio, Iluminada; Arango, Celso; Lobo, Antonio; Sánchez-Torres, Ana M.; Cuesta, Manuel J.
2016-01-01
The objective of this study is to investigate cognitive performance in a first-episode psychosis sample, when stratifying the interaction by cannabis use and familial or non-familial psychosis. Hierarchical-regression models were used to analyse this association in a sample of 268 first-episode psychosis patients and 237 controls. We found that cannabis use was associated with worse working memory, regardless of family history. However, cannabis use was clearly associated with worse cognitive performance in patients with no family history of psychosis, in cognitive domains including verbal memory, executive function and global cognitive index, whereas cannabis users with a family history of psychosis performed better in these domains. The main finding of the study is that there is an interaction between cannabis use and a family history of psychosis in the areas of verbal memory, executive function and global cognition: that is, cannabis use is associated with a better performance in patients with a family history of psychosis and a worse performance in those with no family history of psychosis. In order to confirm this hypothesis, future research should explore the actual expression of the endocannabinoid system in patients with and without a family history of psychosis. PMID:27513670
Quality of Life of Nepalese Women Post Mastectomy
Maharjan, Muna; Thapa, Niresh; Adhikari, Raj Devi; Petrini, Marcia A; Amatya, Kapendra Shekhar
2018-04-25
Introduction: Worldwide breast cancer is the common invasive cancer among the females. The quality of life of women after treatment, which is often a mastectomy, is frequently decreased. Objective: To determine the life quality of Nepalese women post mastectomy. Materials and Methods: One hundred seven women after a mastectomy were selected and interviewed by using the European Organization for Research and Treatment of Cancer-Quality of Life Questionnaire and its Breast Specific Module to assess women’s quality of life. Result: The study findings revealed a good score on global health status/quality of life. The respondents performed well on functional and symptom scales. In the Breast Specific Module, all respondents performed poor regarding sexual function and sexual enjoyment. Global Health Status was found useful among the women involved in service/business/agriculture and the survivors using breast prosthesis. In Breast Specific Module, systemic therapy side effects showed strong statistical associations with age, marital status, occupation, education, use of breast prosthesis and co-morbidity. Body image was highly significant with age, occupation, education, use of breast prosthesis and co-morbidity. Conclusion: Based on the study findings, counseling, and a structured educational programme is recommended to improve the QOL of women after a mastectomy. Creative Commons Attribution License
Xiao, Hu; Cui, Rongxin; Xu, Demin
2018-06-01
This paper presents a cooperative multiagent search algorithm to solve the problem of searching for a target on a 2-D plane under multiple constraints. A Bayesian framework is used to update the local probability density functions (PDFs) of the target when the agents obtain observation information. To obtain the global PDF used for decision making, a sampling-based logarithmic opinion pool algorithm is proposed to fuse the local PDFs, and a particle sampling approach is used to represent the continuous PDF. Then the Gaussian mixture model (GMM) is applied to reconstitute the global PDF from the particles, and a weighted expectation maximization algorithm is presented to estimate the parameters of the GMM. Furthermore, we propose an optimization objective which aims to guide agents to find the target with less resource consumptions, and to keep the resource consumption of each agent balanced simultaneously. To this end, a utility function-based optimization problem is put forward, and it is solved by a gradient-based approach. Several contrastive simulations demonstrate that compared with other existing approaches, the proposed one uses less overall resources and shows a better performance of balancing the resource consumption.
Roca, Patricia; Mulas, Fernando; Gandia, Rubén; Ortiz-Sánchez, Pedro; Abad, Luis
2013-02-22
Evoked potentials P300 and the analysis of executive functions have shown their utility in the monitoring of patients with symptoms of attention deficit hyperactivity disorder (ADHD). Neuropsychological profiles and evoked potentials P300 have been analysed for two groups of children with an ADHD treatment with atomoxetine and methylphenidate respectively. Correlations between P300 and the selected neuropsychological parameters are studied, and the differences between basal values and 1 year follow-up are analysed. Two groups were performed: a group of 22 children ADHD in the atomoxetine condition, and a group of 24 children ADHD in the methylphenidate condition. The results show a global improvement of all the parameters, in terms of executive function and P300 values in both, the atomoxetine and the methylphenidate group. Executive functions and evoked potentials P300 reflect an underlying processing and they are very useful in the clinical practice. This exploratory study shows the importance of designing personalized objective variables-based treatments.
Interactive Videodisc Technology: Applications to the Air Command and Staff College Curriculum.
1988-04-01
objectives )r Executive and NSC system Congress Military Intelligence community Media National environment Transcultural communications Global challenges...Cuban missile crisis REGIONAL STUDIES: USSR AND EUROPE Superpower global objectives The Soviet Union: background The Soviet political-economic system...summary National security affairs review The crisis game WARFARE STUDIES MILITARY HISTORY AND THEORY * - Overview to thinking about war Sun Tzu Great
Tummala, Sudhakar; Palomares, Jose; Kang, Daniel W; Park, Bumhee; Woo, Mary A; Harper, Ronald M; Kumar, Rajesh
2016-01-01
Obstructive sleep apnea (OSA) patients show brain structural injury and functional deficits in autonomic, affective, and cognitive regulatory sites, as revealed by mean diffusivity (MD) and other imaging procedures. The time course and nature of gray and white matter injury can be revealed in more detail with mean kurtosis (MK) procedures, which can differentiate acute from chronic injury, and better show extent of damage over MD procedures. Our objective was to examine global and regional MK changes in newly diagnosed OSA, relative to control subjects. Two diffusion kurtosis image series were collected from 22 recently-diagnosed, treatment-naïve OSA and 26 control subjects using a 3.0-Tesla MRI scanner. MK maps were generated, normalized to a common space, smoothed, and compared voxel-by-voxel between groups using analysis of covariance (covariates; age, sex). No age or sex differences appeared, but body mass index, sleep, neuropsychologic, and cognitive scores significantly differed between groups. MK values were significantly increased globally in OSA over controls, and in multiple localized sites, including the basal forebrain, extending to the hypothalamus, hippocampus, thalamus, insular cortices, basal ganglia, limbic regions, cerebellar areas, parietal cortices, ventral temporal lobe, ventrolateral medulla, and midline pons. Multiple sites, including the insular cortices, ventrolateral medulla, and midline pons showed more injury over previously identified damage with MD procedures, with damage often lateralized. Global mean kurtosis values are significantly increased in obstructive sleep apnea (OSA), suggesting acute tissue injury, and these changes are principally localized in critical sites mediating deficient functions in the condition. The mechanisms for injury likely include altered perfusion and hypoxemia-induced processes, leading to acute tissue changes in recently diagnosed OSA. © 2016 Associated Professional Sleep Societies, LLC.
TDP-43 pathology and memory impairment in elders without pathologic diagnoses of AD or FTLD
Yu, Lei; Wilson, Robert S.; Chen, Er-Yun; Bennett, David A.; Schneider, Julie A.
2017-01-01
Objective: To investigate the association of TAR DNA-binding protein 43 (TDP-43) pathology with memory, other cognitive domains, and dementia in community-dwelling elders without pathologic diagnoses of Alzheimer disease (AD) or frontotemporal lobar degeneration (FTLD). Methods: Of 1,058 autopsied participants, 343 (32.4%) did not have pathologic diagnoses of AD or FTLD. Diagnosis of dementia was based on clinical evaluation and cognitive performance tests, which were used to create summary measures of global cognition and of 5 cognitive domains. TDP-43 pathology evaluated in 6 brain regions by immunohistochemistry was converted into a summary measure of TDP-43 severity. Results: Of 343 participants, 135 (39.4%) had TDP-43 pathology with a mean TDP-43 severity score of 0.394 (SD 0.490). TDP-43 inclusions were confined to the amygdala (stage 1) in 43.7% of participants, 40% showed additional involvement of the hippocampus or entorhinal cortex (stages 2), while fewer (16.3%) showed additional TDP-43 pathology in the temporal and frontal cortices (stage 3). Severity of TDP-43 pathology was independently related to lower function in global cognition and episodic and semantic memory while increased odds of dementia was only a trend. When participants with hippocampal sclerosis (HS) were excluded from the models, TDP-43 pathology remained associated with lower episodic memory but relationships with global cognition, semantic memory, and dementia were attenuated. Conclusions: TDP-43 pathology in elders, without pathologic diagnoses of AD or FTLD, is common and independently associated with lower function in episodic memory, while its associations with global cognitive impairment and dementia are difficult to separate from HS. PMID:28087828
Cognitive Dysfunction in Asian Patients with Depression (CogDAD): A Cross-Sectional Study
Manit, Srisurapanont; Yee Ming, Mok; Yen Kuang, Yang; Herng-Nieng, Chan; Constantine D, Della; Zuraida, Zainal, Nor; Stephen, Jambunathan; Nurmiati, Amir; Pranabi, Kalita
2017-01-01
Background: Cognitive dysfunction is a predominant symptom of Major Depressive Disorder (MDD), contributing to functional impairment. Objective: The primary objective of this study was to assess and describe perceived cognitive dysfunction amongst Asian patients diagnosed with MDD. The secondary objective was to explore the associations between depression severity, perceived cognitive dysfunction and functional disability. Methods: This was a multi-country, multi-centre, cross-sectional study. Adults with a current episode of MDD were recruited from 9 university/general hospital clinics in Asia. During a single study visit, psychiatrists assessed depression severity (Clinical Global Impression-Severity, CGI-S); patients completed questionnaires assessing depression severity (Patient Health Questionnaire-9 items, PHQ-9), perceived cognitive dysfunction (Perceived Deficit Questionnaire-Depression, PDQ-D) and functional disability (Sheehan Disability Scale, SDS). Results: Patients (n=664), predominantly women (66.3%), were aged 46.5±12.5 years, lived in urban areas (81.3%) and were employed (84.6%). 51.5% of patients were having their first depressive episode; 86.7% were receiving treatment; 82.2% had a current episode duration >8 weeks. Patients had mild-to-moderate depression (CGI-S=3.3±1.0; PHQ-9=11.3±6.9). Patients reported perceived cognitive dysfunction (PDQ-D=22.6±16.2) and functional disability (SDS=11.3±7.9). PHQ-9, PDQ-D and SDS were moderately-to-highly correlated (PHQ-9 and SDS: r=0.72; PHQ-9 and PDQ-D: r=0.69; PDQ-D and SDS, r=0.63). ANCOVA showed that after controlling for patient-reported depression severity (PHQ-9), perceived cognitive dysfunction (PDQ-D) was significantly associated with functional disability (SDS) (p<0.001). Conclusions: Asian patients with MDD reported perceived cognitive dysfunction. There is a need for physicians to evaluate cognitive dysfunction in the clinical setting in order to reach treatment goals, including functional recovery beyond remission of mood symptoms. PMID:29238395
Global, Multi-Objective Trajectory Optimization With Parametric Spreading
NASA Technical Reports Server (NTRS)
Vavrina, Matthew A.; Englander, Jacob A.; Phillips, Sean M.; Hughes, Kyle M.
2017-01-01
Mission design problems are often characterized by multiple, competing trajectory optimization objectives. Recent multi-objective trajectory optimization formulations enable generation of globally-optimal, Pareto solutions via a multi-objective genetic algorithm. A byproduct of these formulations is that clustering in design space can occur in evolving the population towards the Pareto front. This clustering can be a drawback, however, if parametric evaluations of design variables are desired. This effort addresses clustering by incorporating operators that encourage a uniform spread over specified design variables while maintaining Pareto front representation. The algorithm is demonstrated on a Neptune orbiter mission, and enhanced multidimensional visualization strategies are presented.
Energy landscapes and properties of biomolecules.
Wales, David J
2005-11-09
Thermodynamic and dynamic properties of biomolecules can be calculated using a coarse-grained approach based upon sampling stationary points of the underlying potential energy surface. The superposition approximation provides an overall partition function as a sum of contributions from the local minima, and hence functions such as internal energy, entropy, free energy and the heat capacity. To obtain rates we must also sample transition states that link the local minima, and the discrete path sampling method provides a systematic means to achieve this goal. A coarse-grained picture is also helpful in locating the global minimum using the basin-hopping approach. Here we can exploit a fictitious dynamics between the basins of attraction of local minima, since the objective is to find the lowest minimum, rather than to reproduce the thermodynamics or dynamics.
NASA Astrophysics Data System (ADS)
Sellars, S. L.; Kawzenuk, B.; Nguyen, P.; Ralph, F. M.; Sorooshian, S.
2017-12-01
The CONNected objECT (CONNECT) algorithm is applied to global Integrated Water Vapor Transport data from the NASA's Modern-Era Retrospective Analysis for Research and Applications - Version 2 reanalysis product for the period of 1980 to 2016. The algorithm generates life-cycle records in time and space evolving strong vapor transport events. We show five regions, located in the midlatitudes, where events typically exist (off the coast of the southeast United States, eastern China, eastern South America, off the southern tip of South Africa, and in the southeastern Pacific Ocean). Global statistics show distinct genesis and termination regions and global seasonal peak frequency during Northern Hemisphere late fall/winter and Southern Hemisphere winter. In addition, the event frequency and geographical location are shown to be modulated by the Arctic Oscillation, Pacific North American Pattern, and the quasi-biennial oscillation. Moreover, a positive linear trend in the annual number of objects is reported, increasing by 3.58 objects year-over-year.
The Role of Civil Society Organizations in Monitoring the Global AIDS Response.
Smith, Julia; Mallouris, Christoforos; Lee, Kelley; Alfvén, Tobias
2017-07-01
Civil society organizations (CSOs) are recognized as playing an exceptional role in the global AIDS response. However, there is little detailed research to date on how they contribute to specific governance functions. This article uses Haas' framework on global governance functions to map CSO's participation in the monitoring of global commitments to the AIDS response by institutions and states. Drawing on key informant interviews and primary documents, it focuses specifically on CSO participation in Global AIDS Response Progress Reporting and in Global Fund to Fight AIDS, Tuberculosis and Malaria processes. It argues that the AIDS response is unique within global health governance, in that CSOs fulfill both formal and informal monitoring functions, and considers the strengths and weaknesses of these contributions. It concludes that future global health governance arrangements should include provisions and resources for monitoring by CSOs because their participation creates more inclusive global health governance and contributes to strengthening commitments to human rights.
NASA Astrophysics Data System (ADS)
Ratajczyk – Piatkowska, Elzbieta
2017-10-01
The principles of the market economy adopted in Poland in the nineties have significantly touched the resources of immovable monuments. As a result, monuments have become a product of culture subject to the rules of the free market; and state ownership, patronage and decision-making practice has now been replaced by private interest. Practical monument use has also changed with the shift in ownership of objects after privatization and further advances in technology and the economy. Accordingly, the subject of this research addresses the issue of ensuring protection as well as the profitability of monumental objects of heritage under private investment in association with municipal and state ownership. The nineties of the twentieth century in Poland marked a period of rapid revival in trade based on market principles and openness to contemporary global trends in the design of commercial facilities. Thus, commercial function as a new use has been used for the commercialization of the monument. After 25 years of experience, it turns out that this new use may pose a threat to the conditions of monument preservation. The spatial and location specifics of the monument are poorly matched to the organizational form of trade and product range, despite the huge variety of these forms; the result is bankruptcy of the commercial operation and the consequent loss of use for the monument. Unused objects will eventually be destroyed. Studies have shown that functions supporting the creation of culture, especially museums, are optimal for the use of monuments. The museum function provides sufficiently high prestige and spatial stability, and allows for the maximum preservation of authentic elements, thus performing an additional role as museum piece.
Kopec, Jacek A.; Colangelo, Linda H.; Land, Stephanie R.; Julian, Thomas B.; Brown, Ann M.; Anderson, Stewart J.; Krag, David N.; Ashikaga, Takamaru; Costantino, Joseph P.; Wolmark, Norman; Ganz, Patricia A.
2012-01-01
Background The impact of arm morbidity following breast cancer surgery on patient-observed changes in daily functioning and health-related quality of life (HRQoL) have not been well-studied. Objective To examine the association of objective measures such as range of motion (ROM) and lymphedema, with patient-reported outcomes (PROs) in the arm and breast, upper extremity function, activities, and HRQoL. Methods The National Surgical Adjuvant Breast and Bowel Project Protocol B-32 was a randomized trial comparing sentinel node resection (SNR) with axillary dissection (AD) in women with node-negative breast cancer. ROM and arm volume were measured objectively. PROs included symptoms; arm function; limitations in social, recreational, occupational, and other regular activities; and a global index of HRQoL. Statistical methods included cross-tabulations and multivariable linear regression models. Results In all, 744 women provided at least 1 postsurgery assessment. About one-third of the patients experienced arm mobility restrictions. A similar number of patients avoided the use of the arm 6 months after surgery. Limitations in work and other regular activities were reported by about a quarter of the patients. In this multivariable analysis, arm mobility and sensory neuropathy were predictors of patient-reported arm function and overall HRQoL. Predictors for activity limitations also included side of surgery (dominant vs nondominant). Edema was not significant after adjustment for sensory neuropathy and ROM. Limitations Arm mobility and edema were measured simultaneously only once during the follow-up (6 months). Conclusion Clinical measures of sensory neuropathy and restrictions in arm mobility following breast cancer surgery are associated with self-reported limitations in activity and reductions in overall HRQoL. PMID:22951047
Second-order optimality conditions for problems with C1 data
NASA Astrophysics Data System (ADS)
Ginchev, Ivan; Ivanov, Vsevolod I.
2008-04-01
In this paper we obtain second-order optimality conditions of Karush-Kuhn-Tucker type and Fritz John one for a problem with inequality constraints and a set constraint in nonsmooth settings using second-order directional derivatives. In the necessary conditions we suppose that the objective function and the active constraints are continuously differentiable, but their gradients are not necessarily locally Lipschitz. In the sufficient conditions for a global minimum we assume that the objective function is differentiable at and second-order pseudoconvex at , a notion introduced by the authors [I. Ginchev, V.I. Ivanov, Higher-order pseudoconvex functions, in: I.V. Konnov, D.T. Luc, A.M. Rubinov (Eds.), Generalized Convexity and Related Topics, in: Lecture Notes in Econom. and Math. Systems, vol. 583, Springer, 2007, pp. 247-264], the constraints are both differentiable and quasiconvex at . In the sufficient conditions for an isolated local minimum of order two we suppose that the problem belongs to the class C1,1. We show that they do not hold for C1 problems, which are not C1,1 ones. At last a new notion parabolic local minimum is defined and it is applied to extend the sufficient conditions for an isolated local minimum from problems with C1,1 data to problems with C1 one.
Global optimization framework for solar building design
NASA Astrophysics Data System (ADS)
Silva, N.; Alves, N.; Pascoal-Faria, P.
2017-07-01
The generative modeling paradigm is a shift from static models to flexible models. It describes a modeling process using functions, methods and operators. The result is an algorithmic description of the construction process. Each evaluation of such an algorithm creates a model instance, which depends on its input parameters (width, height, volume, roof angle, orientation, location). These values are normally chosen according to aesthetic aspects and style. In this study, the model's parameters are automatically generated according to an objective function. A generative model can be optimized according to its parameters, in this way, the best solution for a constrained problem is determined. Besides the establishment of an overall framework design, this work consists on the identification of different building shapes and their main parameters, the creation of an algorithmic description for these main shapes and the formulation of the objective function, respecting a building's energy consumption (solar energy, heating and insulation). Additionally, the conception of an optimization pipeline, combining an energy calculation tool with a geometric scripting engine is presented. The methods developed leads to an automated and optimized 3D shape generation for the projected building (based on the desired conditions and according to specific constrains). The approach proposed will help in the construction of real buildings that account for less energy consumption and for a more sustainable world.
Further Structural Intelligence for Sensors Cluster Technology in Manufacturing
Mekid, Samir
2006-01-01
With the ever increasing complex sensing and actuating tasks in manufacturing plants, intelligent sensors cluster in hybrid networks becomes a rapidly expanding area. They play a dominant role in many fields from macro and micro scale. Global object control and the ability to self organize into fault-tolerant and scalable systems are expected for high level applications. In this paper, new structural concepts of intelligent sensors and networks with new intelligent agents are presented. Embedding new functionalities to dynamically manage cooperative agents for autonomous machines are interesting key enabling technologies most required in manufacturing for zero defects production.
An interactive visualization tool for mobile objects
NASA Astrophysics Data System (ADS)
Kobayashi, Tetsuo
Recent advancements in mobile devices---such as Global Positioning System (GPS), cellular phones, car navigation system, and radio-frequency identification (RFID)---have greatly influenced the nature and volume of data about individual-based movement in space and time. Due to the prevalence of mobile devices, vast amounts of mobile objects data are being produced and stored in databases, overwhelming the capacity of traditional spatial analytical methods. There is a growing need for discovering unexpected patterns, trends, and relationships that are hidden in the massive mobile objects data. Geographic visualization (GVis) and knowledge discovery in databases (KDD) are two major research fields that are associated with knowledge discovery and construction. Their major research challenges are the integration of GVis and KDD, enhancing the ability to handle large volume mobile objects data, and high interactivity between the computer and users of GVis and KDD tools. This dissertation proposes a visualization toolkit to enable highly interactive visual data exploration for mobile objects datasets. Vector algebraic representation and online analytical processing (OLAP) are utilized for managing and querying the mobile object data to accomplish high interactivity of the visualization tool. In addition, reconstructing trajectories at user-defined levels of temporal granularity with time aggregation methods allows exploration of the individual objects at different levels of movement generality. At a given level of generality, individual paths can be combined into synthetic summary paths based on three similarity measures, namely, locational similarity, directional similarity, and geometric similarity functions. A visualization toolkit based on the space-time cube concept exploits these functionalities to create a user-interactive environment for exploring mobile objects data. Furthermore, the characteristics of visualized trajectories are exported to be utilized for data mining, which leads to the integration of GVis and KDD. Case studies using three movement datasets (personal travel data survey in Lexington, Kentucky, wild chicken movement data in Thailand, and self-tracking data in Utah) demonstrate the potential of the system to extract meaningful patterns from the otherwise difficult to comprehend collections of space-time trajectories.
Ventura, Joseph; Reise, Steven P; Keefe, Richard S E; Baade, Lyle E; Gold, James M; Green, Michael F; Kern, Robert S; Mesholam-Gately, Raquelle; Nuechterlein, Keith H; Seidman, Larry J; Bilder, Robert M
2010-08-01
Practical, reliable "real world" measures of cognition are needed to supplement neurocognitive performance data to evaluate possible efficacy of new drugs targeting cognitive deficits associated with schizophrenia. Because interview-based measures of cognition offer one possible approach, data from the MATRICS initiative (n=176) were used to examine the psychometric properties of the Schizophrenia Cognition Rating Scale (SCoRS) and the Clinical Global Impression of Cognition in Schizophrenia (CGI-CogS). We used classical test theory methods and item response theory to derive the 10-item Cognitive Assessment Interview (CAI) from the SCoRS and CGI-CogS ("parent instruments"). Sources of information for CAI ratings included the patient and an informant. Validity analyses examined the relationship between the CAI and objective measures of cognitive functioning, intermediate measures of cognition, and functional outcome. The rater's score from the newly derived CAI (10 items) correlate highly (r=.87) with those from the combined set of the SCoRS and CGI-CogS (41 items). Both the patient (r=.82) and the informant (r=.95) data were highly correlated with the rater's score. The CAI was modestly correlated with objectively measured neurocognition (r=-.32), functional capacity (r=-.44), and functional outcome (r=-.32), which was comparable to the parent instruments. The CAI allows for expert judgment in evaluating a patient's cognitive functioning and was modestly correlated with neurocognitive functioning, functional capacity, and functional outcome. The CAI is a brief, repeatable, and potentially valuable tool for rating cognition in schizophrenia patients who are participating in clinical trials. Copyright 2010 Elsevier B.V. All rights reserved.
Ventura, Joseph; Reise, Steven P.; Keefe, Richard S. E.; Baade, Lyle E.; Gold, James M.; Green, Michael F.; Kern, Robert S.; Mesholam-Gately, Raquelle; Nuechterlein, Keith H.; Seidman, Larry J.; Bilder, Robert M.
2011-01-01
Background Practical, reliable “real world” measures of cognition are needed to supplement neurocognitive performance data to evaluate possible efficacy of new drugs targeting cognitive deficits associated with schizophrenia. Because interview-based measures of cognition offer one possible approach, data from the MATRICS initiative (n=176) were used to examine the psychometric properties of the Schizophrenia Cognition Rating Scale (SCoRS) and the Clinical Global Impression of Cognition in Schizophrenia (CGI-CogS). Method We used classical test theory methods and item response theory to derive the 10 item Cognitive Assessment Interview (CAI) from the SCoRS and CGI-Cogs (“parent instruments”). Sources of information for CAI ratings included the patient and an informant. Validity analyses examined the relationship between the CAI and objective measures of cognitive functioning, intermediate measures of cognition, and functional outcome. Results The rater’s score from the newly derived CAI (10-items) correlate highly (r = .87) with those from the combined set of the SCoRS and CGI-CogS (41 items). Both the patient (r= .82) and the informant (r= .95) data were highly correlated with the rater’s score. The CAI was modestly correlated with objectively measured neurocognition (r = −.32), functional capacity (r = −.44), and functional outcome (r = −.32), which was comparable to the parent instruments. Conclusions The CAI allows for expert judgment in evaluating a patient’s cognitive functioning and was modestly correlated with neurocognitive functioning, functional capacity, and functional outcome. The CAI is a brief, repeatable, and potentially valuable tool for rating cognition in schizophrenia patients who are participating in clinical trials. PMID:20542412
Dynapenic-obesity and physical function in older adults.
Bouchard, Danielle R; Janssen, Ian
2010-01-01
Dynapenia (low muscle strength) and obesity are associated with an impaired physical function. It was hypothesized that older individuals with both conditions (dynapenic-obesity) would have a more impaired physical function than individuals with dynapenia or obesity alone. This cross-sectional study included 2,039 men and women aged 55 years and older from the 1999-2002 National Health and Nutrition Examination Survey. Fat mass was measured by dual-energy x-ray absorptiometry and leg strength by dynamometer. Based on fat mass and leg strength tertiles, four independent groups were identified: non-dynapenic and non-obese, obese alone, dynapenic alone, and dynapenic-obese. An objective physical function measure was obtained from a 20-foot walking speed test, whereas subjective physical function measures were obtained from five self-reported questions. Within both sexes, the dynapenic-obese group had a slower walking speed than the non-dynapenic and non-obese and obese-alone groups (p
Chandana, Sreenivasa R; Behen, Michael E; Juhász, Csaba; Muzik, Otto; Rothermel, Robert D; Mangner, Thomas J; Chakraborty, Pulak K; Chugani, Harry T; Chugani, Diane C
2005-01-01
The role of serotonin in prenatal and postnatal brain development is well documented in the animal literature. In earlier studies using positron emission tomography (PET) with the tracer alpha[(11)C]methyl-l-tryptophan (AMT), we reported global and focal abnormalities of serotonin synthesis in children with autism. In the present study, we measured brain serotonin synthesis in a large group of autistic children (n = 117) with AMT PET and related these neuroimaging data to handedness and language function. Cortical AMT uptake abnormalities were objectively derived from small homotopic cortical regions using a predefined cutoff asymmetry threshold (>2 S.D. of normal asymmetry). Autistic children demonstrated several patterns of abnormal cortical involvement, including right cortical, left cortical, and absence of abnormal asymmetry. Global brain values for serotonin synthesis capacity (unidirectional uptake rate constant, K-complex) values were plotted as a function of age. K-complex values of autistic children with asymmetry or no asymmetry in cortical AMT uptake followed different developmental patterns, compared to that of a control group of non-autistic children. The autism groups, defined by presence or absence and side of cortical asymmetry, differed on a measure of language as well as handedness. Autistic children with left cortical AMT decreases showed a higher prevalence of severe language impairment, whereas those with right cortical decreases showed a higher prevalence of left and mixed handedness. Global as well as focal abnormally asymmetric development in the serotonergic system could lead to miswiring of the neural circuits specifying hemispheric specialization.
NASA Astrophysics Data System (ADS)
Poyatos, R.; Granda, V.; Mencuccini, M.; Flo, V.; Oren, R.; Molowny-Horas, R.; Katul, G. G.; Mahecha, M. D.; Steppe, K.; Cabon, A.; De Cáceres, M.; Martínez-Vilalta, J.
2017-12-01
Plant transpiration is the fundamental process linking water and vegetation and it is therefore a central topic in ecohydrological research. Globally, plants display a huge variety of coordinated adjustments in their physiology and structure to regulate transpiration in response to fluctuations of water demand and supply at multiple temporal scales. Sap flow measured in plant stems reveals the temporal patterns of these responses but sap flow data have remained fragmentary and generally unavailable for syntheses of regional to global scope. Here we present the first global database of sap flow measurements from individual plants (SAPFLUXNET, http://sapfluxnet.creaf.cat/), which has been compiled from > 150 datasets contributed by researchers worldwide. Received datasets were harmonised and conveniently stored in custom-designed R objects holding sap flow and environmental data time series, together with several ancillary metadata, enabling data access for synthesis activities. SAPFLUXNET covers most vegetated biomes and holds data for > 1500 individual plants, mostly trees, belonging to >100 species and > 50 genera. We retrieved water use traits indicative of maximum transpiration rates and of transpiration sensitivity to vapour pressure deficit using quantile regression approaches and moving window analyses. Global patterns of these water use traits were then analysed as a function of climate, plant functional type and stand characteristics. For example, maximum transpiration rates at a given plant diameter or sapwood area tended to be higher for Angiosperms compared to Gymnosperms, but this relationships converged to a more similar scaling between transpiration and leaf area across these groups. SAPFLUXNET is also a valuable tool to evaluate water balance components in ecosystem models. We combined SAPFLUXNET data with the MEDFATE model (https://cran.r-project.org/web/packages/medfate/index.html) to validate an ecohydrological optimisation approach to retrieve root distribution parameters at a regional scale. SAPFLUXNET is therefore a promising resource for ecohydrologists as it can complement other transpiration quantifications obtained from eddy flux, isotopic or catchment water balance data.
NASA Astrophysics Data System (ADS)
Hayes, M.
2014-12-01
The IMBECS Protocol concept employs large cultivation and biorefinery installations, within the five Subtropical Convergence Zones (STCZs), to support the production of commodities such as carbon negative biofuels, seafood, organic fertilizer, polymers and freshwater, as a flexible and cost effective means of Global Warming Mitigation (GWM) with the primary objective being the global scale replacement of fossil fuels (FF). This governance approach is categorically distinct from all other large scale GWM governance concepts. Yet, many of the current marine related GWM technologies are adaptable to this proposals. The IMBECS technology would be managed by an intergovernmentally sanctioned non-profit foundation which would have the following functions/mission: Synthesises relevant treaty language Performs R&D activities and purchases relevant patents Under intergovernmental commission, functions as the primary responsible international actorfor environmental standards, production quotas and operational integrity Licence technology to for-profit actors under strict production/environmental standards Enforce production and environmental standards along with production quotas Provide a high level of transparency to all stakeholders Provide legal defence The IMBECS Protocol is conceptually related to the work found in the following documents/links. This list is not exhaustive: Climate Change Geoengineering The Science and Politics of Global Climate Change: A guide to the debate IPCC Special Report on Renewable Energy and Climate Change Mitigation DoE Roadmap for Algae Biofuels PodEnergy Ocean Agronomy development leaders and progenitor of this proposal. Artificial Upwelling of Deep Seawater Using the Perpetual Salt Fountain for Cultivation of Ocean Desert NASAs' OMEGA study. Cool Planet; Land based version of a carbon negative biofuel concept. Cellana; Leading developer of algae based bioproducts. The State of World Fisheries and Aquaculture Mariculture: A global analysis of production trends since 1950 BECCS /Biochar/ Olivine UNFCCC/IMO/CBD The President's Climate Action Plan The conclusion of this analysis calls for funding of an investigational deployment of the relevant technologies for an open evaluation at the intergovernmental level.
Real-Time 3D Tracking and Reconstruction on Mobile Phones.
Prisacariu, Victor Adrian; Kähler, Olaf; Murray, David W; Reid, Ian D
2015-05-01
We present a novel framework for jointly tracking a camera in 3D and reconstructing the 3D model of an observed object. Due to the region based approach, our formulation can handle untextured objects, partial occlusions, motion blur, dynamic backgrounds and imperfect lighting. Our formulation also allows for a very efficient implementation which achieves real-time performance on a mobile phone, by running the pose estimation and the shape optimisation in parallel. We use a level set based pose estimation but completely avoid the, typically required, explicit computation of a global distance. This leads to tracking rates of more than 100 Hz on a desktop PC and 30 Hz on a mobile phone. Further, we incorporate additional orientation information from the phone's inertial sensor which helps us resolve the tracking ambiguities inherent to region based formulations. The reconstruction step first probabilistically integrates 2D image statistics from selected keyframes into a 3D volume, and then imposes coherency and compactness using a total variational regularisation term. The global optimum of the overall energy function is found using a continuous max-flow algorithm and we show that, similar to tracking, the integration of per voxel posteriors instead of likelihoods improves the precision and accuracy of the reconstruction.
Identification of vehicle suspension parameters by design optimization
NASA Astrophysics Data System (ADS)
Tey, J. Y.; Ramli, R.; Kheng, C. W.; Chong, S. Y.; Abidin, M. A. Z.
2014-05-01
The design of a vehicle suspension system through simulation requires accurate representation of the design parameters. These parameters are usually difficult to measure or sometimes unavailable. This article proposes an efficient approach to identify the unknown parameters through optimization based on experimental results, where the covariance matrix adaptation-evolutionary strategy (CMA-es) is utilized to improve the simulation and experimental results against the kinematic and compliance tests. This speeds up the design and development cycle by recovering all the unknown data with respect to a set of kinematic measurements through a single optimization process. A case study employing a McPherson strut suspension system is modelled in a multi-body dynamic system. Three kinematic and compliance tests are examined, namely, vertical parallel wheel travel, opposite wheel travel and single wheel travel. The problem is formulated as a multi-objective optimization problem with 40 objectives and 49 design parameters. A hierarchical clustering method based on global sensitivity analysis is used to reduce the number of objectives to 30 by grouping correlated objectives together. Then, a dynamic summation of rank value is used as pseudo-objective functions to reformulate the multi-objective optimization to a single-objective optimization problem. The optimized results show a significant improvement in the correlation between the simulated model and the experimental model. Once accurate representation of the vehicle suspension model is achieved, further analysis, such as ride and handling performances, can be implemented for further optimization.
Energy in an Interdependent World: A Global Development Studies Case Study.
ERIC Educational Resources Information Center
Collier, Anne B.
Part of the Global Development Studies Institute series of model curricula, the teacher guide presents strategies for teaching about energy as a global issue. The unit, intended for students in grades 11-14, is designed for one semester. The overall objective is to promote awareness of and responsibility toward the global community through an…
ERIC Educational Resources Information Center
New York City Board of Education, Brooklyn, NY. Div. of Curriculum and Instruction.
Designed to assist teachers and supervisors in the implementation of the global history course, this bulletin presents learning activities which include the rationale, performance objectives, and teaching strategies related to Theme V entitled, "The Industrial Revolution Had Global Impact." This theme has seven subthemes: (1)…
Global dynamic optimization approach to predict activation in metabolic pathways.
de Hijas-Liste, Gundián M; Klipp, Edda; Balsa-Canto, Eva; Banga, Julio R
2014-01-06
During the last decade, a number of authors have shown that the genetic regulation of metabolic networks may follow optimality principles. Optimal control theory has been successfully used to compute optimal enzyme profiles considering simple metabolic pathways. However, applying this optimal control framework to more general networks (e.g. branched networks, or networks incorporating enzyme production dynamics) yields problems that are analytically intractable and/or numerically very challenging. Further, these previous studies have only considered a single-objective framework. In this work we consider a more general multi-objective formulation and we present solutions based on recent developments in global dynamic optimization techniques. We illustrate the performance and capabilities of these techniques considering two sets of problems. First, we consider a set of single-objective examples of increasing complexity taken from the recent literature. We analyze the multimodal character of the associated non linear optimization problems, and we also evaluate different global optimization approaches in terms of numerical robustness, efficiency and scalability. Second, we consider generalized multi-objective formulations for several examples, and we show how this framework results in more biologically meaningful results. The proposed strategy was used to solve a set of single-objective case studies related to unbranched and branched metabolic networks of different levels of complexity. All problems were successfully solved in reasonable computation times with our global dynamic optimization approach, reaching solutions which were comparable or better than those reported in previous literature. Further, we considered, for the first time, multi-objective formulations, illustrating how activation in metabolic pathways can be explained in terms of the best trade-offs between conflicting objectives. This new methodology can be applied to metabolic networks with arbitrary topologies, non-linear dynamics and constraints.
[Categorization in infancy: differentiation of global object classes].
Pauen, S
1996-01-01
Two studies tested whether preverbal children distinguish global categories (animal and furniture) on a conceptual basis. A total of 59 eleven-month-olds solved an object examination task. During habituation, infants freely explored different natural-looking toy models from the same category. In Study 1, the same series of four different examplars was presented twice. In Study 2, ten different exemplares were presented. In both cases, a significant habituation effect could be observed. When a perceptually new object of the same category was presented on the first test trial after habituation, a significant increase in examination time from the last habituation trial to the first test trial could be observed in Study 1. When a new object of the contrasting category was presented on the second test trial, examination times increased significantly from the first to the second test trial in both studies. These results support earlier findings suggesting that preverbal infants are able to distinguish global categories on a conceptual basis.
SEMI-SUPERVISED OBJECT RECOGNITION USING STRUCTURE KERNEL
Wang, Botao; Xiong, Hongkai; Jiang, Xiaoqian; Ling, Fan
2013-01-01
Object recognition is a fundamental problem in computer vision. Part-based models offer a sparse, flexible representation of objects, but suffer from difficulties in training and often use standard kernels. In this paper, we propose a positive definite kernel called “structure kernel”, which measures the similarity of two part-based represented objects. The structure kernel has three terms: 1) the global term that measures the global visual similarity of two objects; 2) the part term that measures the visual similarity of corresponding parts; 3) the spatial term that measures the spatial similarity of geometric configuration of parts. The contribution of this paper is to generalize the discriminant capability of local kernels to complex part-based object models. Experimental results show that the proposed kernel exhibit higher accuracy than state-of-art approaches using standard kernels. PMID:23666108
The competency of internists in holistic global care to support healthy Indonesia 2010.
Rudijanto, Achmad
2006-01-01
All patients are entitled to good standards of practice and care from their doctors. The improved health of all peoples is the main goal of medical education, including for the education of internal medicine registrars. The future development of the direction and goal of education, the level of competence of internal medicine specialists, and the process of learning will be related to preparing the internal medicine specialist to have global competitive advantage. Identification of general competencies is the first step in a long-term effort designed to emphasize educational outcome, for assessment in residency programs, and in the accreditation process. To achieve that competence, a variety of learning opportunities need to be provided in order that the resident can achieve the necessary knowledge, skills, attitude, and behaviors. Identification of the role and function of internal medicine specialists is needed prior to the development of the general competencies. As educational objectives, the competencies fall into two main categories: knowledge-based and performance-based. Knowledge-based competency has two components, medical knowledge (bio-science and clinical medicine) and contextual knowledge (epidemiology, health service organization, and human behavior). The performance base has two components, intellectual skills and the interpersonal skills. Besides the two main categories of educational objectives, there are behavioral objectives that residents must achieve through the educational program, to ensure that residents are able to deal with a range of prescribed clinical situations effectively, safely, humanely, and economically. The achievement of behavioral objectives will ensure, at least in part, that the doctor will implement good medical practice. The index clinical/community situations (ICS) on which the educational objectives will be based are taken from diseases and illnesses that occur in clinical and community settings. No resident can master all medicine there is to know, as there are no limits to what can be known about medicine. It is important to make choices in selecting what residents should learn by analyzing the ICS.
Endogenous sex hormones and cognitive function in the elderly.
Boss, Lisa; Kang, Duck-Hee; Bergstrom, Nancy; Leasure, J Leigh
2015-08-01
Estrogen and testosterone may influence cognitive function in the older adult, but the relationship between sex hormones and cognitive function is complex. To examine associations of sex hormones and cognitive function among older adults ≥65 years old. Using a cross-sectional research design, data were collected once from 71 elderly (mean age 86.4 years). Global cognitive function and executive function were measured with standardized instruments, and saliva samples were collected for salivary estradiol and testosterone. Estradiol was significantly and positively correlated with global cognitive function in men only (r = 0.54, p < 0.05). Testosterone was not significantly correlated with global cognitive function or executive function in either gender. Associations between sex hormones and cognitive function were mostly non-significant. However, higher estradiol was significantly correlated with better global cognitive function in men, suggesting gender-specific differences. Along with sex hormones, other comorbidity may need to be assessed together in relation to cognitive function in the elderly. Accordingly, clinicians play an important role in educating and promoting beneficial actions to preserve cognitive function.
Reliability based design including future tests and multiagent approaches
NASA Astrophysics Data System (ADS)
Villanueva, Diane
The initial stages of reliability-based design optimization involve the formulation of objective functions and constraints, and building a model to estimate the reliability of the design with quantified uncertainties. However, even experienced hands often overlook important objective functions and constraints that affect the design. In addition, uncertainty reduction measures, such as tests and redesign, are often not considered in reliability calculations during the initial stages. This research considers two areas that concern the design of engineering systems: 1) the trade-off of the effect of a test and post-test redesign on reliability and cost and 2) the search for multiple candidate designs as insurance against unforeseen faults in some designs. In this research, a methodology was developed to estimate the effect of a single future test and post-test redesign on reliability and cost. The methodology uses assumed distributions of computational and experimental errors with re-design rules to simulate alternative future test and redesign outcomes to form a probabilistic estimate of the reliability and cost for a given design. Further, it was explored how modeling a future test and redesign provides a company an opportunity to balance development costs versus performance by simultaneously designing the design and the post-test redesign rules during the initial design stage. The second area of this research considers the use of dynamic local surrogates, or surrogate-based agents, to locate multiple candidate designs. Surrogate-based global optimization algorithms often require search in multiple candidate regions of design space, expending most of the computation needed to define multiple alternate designs. Thus, focusing on solely locating the best design may be wasteful. We extended adaptive sampling surrogate techniques to locate multiple optima by building local surrogates in sub-regions of the design space to identify optima. The efficiency of this method was studied, and the method was compared to other surrogate-based optimization methods that aim to locate the global optimum using two two-dimensional test functions, a six-dimensional test function, and a five-dimensional engineering example.
Autistic and schizotypal traits and global functioning in bipolar I disorder.
Abu-Akel, Ahmad; Clark, Jennifer; Perry, Amy; Wood, Stephen J; Forty, Liz; Craddock, Nick; Jones, Ian; Gordon-Smith, Katherine; Jones, Lisa
2017-01-01
To determine the expression of autistic and positive schizotypal traits in a large sample of adults with bipolar I disorder (BD I), and the effect of co-occurring autistic and positive schizotypal traits on global functioning in BD I. Autistic and positive schizotypal traits were self-assessed in 797 individuals with BD-I recruited by the Bipolar Disorder Research Network. Differences in global functioning (rated using the Global Assessment Scale) during lifetime worst depressive and manic episodes (GASD and GASM respectively) were calculated in groups with high/low autistic and positive schizotypal traits. Regression analyses assessed the interactive effect of autistic and positive schizotypal traits on global functioning. 47.2% (CI=43.7-50.7%) showed clinically significant levels of autistic traits, and 23.22% (95% CI=20.29-26.14) showed clinically significant levels of positive schizotypal traits. In the worst episode of mania, the high autistic, high positive schizotypal group had better global functioning compared to the other groups. Individual differences analyses showed that high levels of both traits were associated with better global functioning in both mood states. Autistic and schizotypal traits were assessed using self-rated questionnaires. Expression of autistic and schizotypal traits in adults with BD I is prevalent, and may be important to predict illness aetiology, prognosis, and diagnostic practices in this population. Future work should focus on replicating these findings in independent samples, and on the biological and/or psychosocial mechanisms underlying better global functioning in those who have high levels of both autistic and positive schizotypal traits. Copyright © 2016 Elsevier B.V. All rights reserved.
Microenvironmental change as a mechanism to study global change.
NASA Astrophysics Data System (ADS)
Lortie, C. J.
2016-12-01
Global change is a set of significant processes that influence all aspects of ecosystem functioning and often-natural services within Santa Barbara County. The sensitivity of coastal and urban systems is certainly very high. However, profound changes are also predicted for arid and semi-arid systems globally, and California is no exception. These dryland systems are less buffered by oceanic processes and typically express high inter-annual variation in precipitation and temperatures in addition to perturbations associated with long-term droughts. However, climate estimates and downscaled values can present challenges in providing evidence at the scale relevant to individual species or individuals, and the importance of biotic interactions must be coupled to these estimates in space and time. Coupled indicators of key micro-environmental measures to both positive and negative interactions between foundation species and other organisms provide a metric of buffering capacity and resilience to global change at fine spatial scales. Consequently, the primary objective of this research project is to provide both the a well-articulated, ecologically relevant micro-environmental big data measure of global change within Santa Barbara County and a coupled estimate of concurrent changes in interactions in key species within the region. Shrubs directly and indirectly buffered local changes in the microenvironment thereby functioning as refuges for other species within arid and semi-arid regions subject to dramatic global change drivers. The following major patterns were identified: (i) shrub micro-environments reduce the level of stress and amplitude of variation associated with temperature and moisture, (ii) many plant and animal species including threatened lizards are relatively more common with shrubs within the region, and (iii) the variation in the interaction patterns between species relates to the extent of amelioration provided by shrub-biodiversity complexes within the region. The ecological theory of positive plant interactions scaling to other species as a restoration and management tool is a dominant and rapidly evolving field of research. Micro-environmental sensor arrays are a scientifically valid approach to identify meaningful localized change with biotic interactions.
Naser, Mohamed A.; Patterson, Michael S.
2011-01-01
Reconstruction algorithms are presented for two-step solutions of the bioluminescence tomography (BLT) and the fluorescence tomography (FT) problems. In the first step, a continuous wave (cw) diffuse optical tomography (DOT) algorithm is used to reconstruct the tissue optical properties assuming known anatomical information provided by x-ray computed tomography or other methods. Minimization problems are formed based on L1 norm objective functions, where normalized values for the light fluence rates and the corresponding Green’s functions are used. Then an iterative minimization solution shrinks the permissible regions where the sources are allowed by selecting points with higher probability to contribute to the source distribution. Throughout this process the permissible region shrinks from the entire object to just a few points. The optimum reconstructed bioluminescence and fluorescence distributions are chosen to be the results of the iteration corresponding to the permissible region where the objective function has its global minimum This provides efficient BLT and FT reconstruction algorithms without the need for a priori information about the bioluminescence sources or the fluorophore concentration. Multiple small sources and large distributed sources can be reconstructed with good accuracy for the location and the total source power for BLT and the total number of fluorophore molecules for the FT. For non-uniform distributed sources, the size and magnitude become degenerate due to the degrees of freedom available for possible solutions. However, increasing the number of data points by increasing the number of excitation sources can improve the accuracy of reconstruction for non-uniform fluorophore distributions. PMID:21326647
Efficient Generation of Dancing Animation Synchronizing with Music Based on Meta Motion Graphs
NASA Astrophysics Data System (ADS)
Xu, Jianfeng; Takagi, Koichi; Sakazawa, Shigeyuki
This paper presents a system for automatic generation of dancing animation that is synchronized with a piece of music by re-using motion capture data. Basically, the dancing motion is synthesized according to the rhythm and intensity features of music. For this purpose, we propose a novel meta motion graph structure to embed the necessary features including both rhythm and intensity, which is constructed on the motion capture database beforehand. In this paper, we consider two scenarios for non-streaming music and streaming music, where global search and local search are required respectively. In the case of the former, once a piece of music is input, the efficient dynamic programming algorithm can be employed to globally search a best path in the meta motion graph, where an objective function is properly designed by measuring the quality of beat synchronization, intensity matching, and motion smoothness. In the case of the latter, the input music is stored in a buffer in a streaming mode, then an efficient search method is presented for a certain amount of music data (called a segment) in the buffer with the same objective function, resulting in a segment-based search approach. For streaming applications, we define an additional property in the above meta motion graph to deal with the unpredictable future music, which guarantees that there is some motion to match the unknown remaining music. A user study with totally 60 subjects demonstrates that our system outperforms the stat-of-the-art techniques in both scenarios. Furthermore, our system improves the synthesis speed greatly (maximal speedup is more than 500 times), which is essential for mobile applications. We have implemented our system on commercially available smart phones and confirmed that it works well on these mobile phones.
Allan, Richard P.; Mayer, Michael; Hyder, Patrick; Loeb, Norman G.; Roberts, Chris D.; Valdivieso, Maria; Edwards, John M.; Vidale, Pier‐Luigi
2017-01-01
Abstract The net surface energy flux is central to the climate system yet observational limitations lead to substantial uncertainty. A combination of satellite‐derived radiative fluxes at the top of atmosphere adjusted using the latest estimation of the net heat uptake of the Earth system, and the atmospheric energy tendencies and transports from the ERA‐Interim reanalysis are used to estimate surface energy flux globally. To consider snowmelt and improve regional realism, land surface fluxes are adjusted through a simple energy balance approach at each grid point. This energy adjustment is redistributed over the oceans to ensure energy conservation and maintain realistic global ocean heat uptake, using a weighting function to avoid meridional discontinuities. Calculated surface energy fluxes are evaluated through comparison to ocean reanalyses. Derived turbulent energy flux variability is compared with the Objectively Analyzed air‐sea Fluxes (OAFLUX) product, and inferred meridional energy transports in the global ocean and the Atlantic are also evaluated using observations. Uncertainties in surface fluxes are investigated using a variety of approaches including comparison with a range of atmospheric reanalysis products. Decadal changes in the global mean and the interhemispheric energy imbalances are quantified, and present day cross‐equator heat transports are reevaluated at 0.22 ± 0.15 PW (petawatts) southward by the atmosphere and 0.32 ± 0.16 PW northward by the ocean considering the observed ocean heat sinks. PMID:28804697
Nakanishi, Masaki; Wang, Yu-Te; Jung, Tzyy-Ping; Zao, John K; Chien, Yu-Yi; Diniz-Filho, Alberto; Daga, Fabio B; Lin, Yuan-Pin; Wang, Yijun; Medeiros, Felipe A
2017-06-01
The current assessment of visual field loss in diseases such as glaucoma is affected by the subjectivity of patient responses and the lack of portability of standard perimeters. To describe the development and initial validation of a portable brain-computer interface (BCI) for objectively assessing visual function loss. This case-control study involved 62 eyes of 33 patients with glaucoma and 30 eyes of 17 healthy participants. Glaucoma was diagnosed based on a masked grading of optic disc stereophotographs. All participants underwent testing with a BCI device and standard automated perimetry (SAP) within 3 months. The BCI device integrates wearable, wireless, dry electroencephalogram and electrooculogram systems and a cellphone-based head-mounted display to enable the detection of multifocal steady state visual-evoked potentials associated with visual field stimulation. The performances of global and sectoral multifocal steady state visual-evoked potentials metrics to discriminate glaucomatous from healthy eyes were compared with global and sectoral SAP parameters. The repeatability of the BCI device measurements was assessed by collecting results of repeated testing in 20 eyes of 10 participants with glaucoma for 3 sessions of measurements separated by weekly intervals. Receiver operating characteristic curves summarizing diagnostic accuracy. Intraclass correlation coefficients and coefficients of variation for assessing repeatability. Among the 33 participants with glaucoma, 19 (58%) were white, 12 (36%) were black, and 2 (6%) were Asian, while among the 17 participants with healthy eyes, 9 (53%) were white, 8 (47%) were black, and none were Asian. The receiver operating characteristic curve area for the global BCI multifocal steady state visual-evoked potentials parameter was 0.92 (95% CI, 0.86-0.96), which was larger than for SAP mean deviation (area under the curve, 0.81; 95% CI, 0.72-0.90), SAP mean sensitivity (area under the curve, 0.80; 95% CI, 0.69-0.88; P = .03), and SAP pattern standard deviation (area under the curve, 0.77; 95% CI, 0.66-0.87; P = .01). No statistically significant differences were seen for the sectoral measurements between the BCI and SAP. Intraclass coefficients for global and sectoral parameters ranged from 0.74 to 0.92, and mean coefficients of variation ranged from 3.03% to 7.45%. The BCI device may be useful for assessing the electrical brain responses associated with visual field stimulation. The device discriminated eyes with glaucomatous neuropathy from healthy eyes in a clinically based setting. Further studies should investigate the feasibility of the BCI device for home-based testing as well as for detecting visual function loss over time.
Rapid Processing of a Global Feature in the ON Visual Pathways of Behaving Monkeys.
Huang, Jun; Yang, Yan; Zhou, Ke; Zhao, Xudong; Zhou, Quan; Zhu, Hong; Yang, Yingshan; Zhang, Chunming; Zhou, Yifeng; Zhou, Wu
2017-01-01
Visual objects are recognized by their features. Whereas, some features are based on simple components (i.e., local features, such as orientation of line segments), some features are based on the whole object (i.e., global features, such as an object having a hole in it). Over the past five decades, behavioral, physiological, anatomical, and computational studies have established a general model of vision, which starts from extracting local features in the lower visual pathways followed by a feature integration process that extracts global features in the higher visual pathways. This local-to-global model is successful in providing a unified account for a vast sets of perception experiments, but it fails to account for a set of experiments showing human visual systems' superior sensitivity to global features. Understanding the neural mechanisms underlying the "global-first" process will offer critical insights into new models of vision. The goal of the present study was to establish a non-human primate model of rapid processing of global features for elucidating the neural mechanisms underlying differential processing of global and local features. Monkeys were trained to make a saccade to a target in the black background, which was different from the distractors (white circle) in color (e.g., red circle target), local features (e.g., white square target), a global feature (e.g., white ring with a hole target) or their combinations (e.g., red square target). Contrary to the predictions of the prevailing local-to-global model, we found that (1) detecting a distinction or a change in the global feature was faster than detecting a distinction or a change in color or local features; (2) detecting a distinction in color was facilitated by a distinction in the global feature, but not in the local features; and (3) detecting the hole was interfered by the local features of the hole (e.g., white ring with a squared hole). These results suggest that monkey ON visual systems have a subsystem that is more sensitive to distinctions in the global feature than local features. They also provide the behavioral constraints for identifying the underlying neural substrates.
Synchronous parallel system for emulation and discrete event simulation
NASA Technical Reports Server (NTRS)
Steinman, Jeffrey S. (Inventor)
1992-01-01
A synchronous parallel system for emulation and discrete event simulation having parallel nodes responds to received messages at each node by generating event objects having individual time stamps, stores only the changes to state variables of the simulation object attributable to the event object, and produces corresponding messages. The system refrains from transmitting the messages and changing the state variables while it determines whether the changes are superseded, and then stores the unchanged state variables in the event object for later restoral to the simulation object if called for. This determination preferably includes sensing the time stamp of each new event object and determining which new event object has the earliest time stamp as the local event horizon, determining the earliest local event horizon of the nodes as the global event horizon, and ignoring the events whose time stamps are less than the global event horizon. Host processing between the system and external terminals enables such a terminal to query, monitor, command or participate with a simulation object during the simulation process.
Synchronous Parallel System for Emulation and Discrete Event Simulation
NASA Technical Reports Server (NTRS)
Steinman, Jeffrey S. (Inventor)
2001-01-01
A synchronous parallel system for emulation and discrete event simulation having parallel nodes responds to received messages at each node by generating event objects having individual time stamps, stores only the changes to the state variables of the simulation object attributable to the event object and produces corresponding messages. The system refrains from transmitting the messages and changing the state variables while it determines whether the changes are superseded, and then stores the unchanged state variables in the event object for later restoral to the simulation object if called for. This determination preferably includes sensing the time stamp of each new event object and determining which new event object has the earliest time stamp as the local event horizon, determining the earliest local event horizon of the nodes as the global event horizon, and ignoring events whose time stamps are less than the global event horizon. Host processing between the system and external terminals enables such a terminal to query, monitor, command or participate with a simulation object during the simulation process.
1990-04-01
addition to a detailed description of the Situation Awareness Global Assessment Technique (SAGAT). SAGAT was developed as an objective measure of a... developed aircraft designs and training programs hinges on en objective evaluation program that considers the global SA reqluirements of the pilot. Bsy...roll-attitudae recovery [323, and that thickened negative pitch lines (simulating lirm grad-ents) are particularly effective in improving
Ben Ayed, Ismail; Punithakumar, Kumaradevan; Garvin, Gregory; Romano, Walter; Li, Shuo
2011-01-01
This study investigates novel object-interaction priors for graph cut image segmentation with application to intervertebral disc delineation in magnetic resonance (MR) lumbar spine images. The algorithm optimizes an original cost function which constrains the solution with learned prior knowledge about the geometric interactions between different objects in the image. Based on a global measure of similarity between distributions, the proposed priors are intrinsically invariant with respect to translation and rotation. We further introduce a scale variable from which we derive an original fixed-point equation (FPE), thereby achieving scale-invariance with only few fast computations. The proposed priors relax the need of costly pose estimation (or registration) procedures and large training sets (we used a single subject for training), and can tolerate shape deformations, unlike template-based priors. Our formulation leads to an NP-hard problem which does not afford a form directly amenable to graph cut optimization. We proceeded to a relaxation of the problem via an auxiliary function, thereby obtaining a nearly real-time solution with few graph cuts. Quantitative evaluations over 60 intervertebral discs acquired from 10 subjects demonstrated that the proposed algorithm yields a high correlation with independent manual segmentations by an expert. We further demonstrate experimentally the invariance of the proposed geometric attributes. This supports the fact that a single subject is sufficient for training our algorithm, and confirms the relevance of the proposed priors to disc segmentation.
High fat diet-induced diabetes in mice exacerbates cognitive deficit due to chronic hypoperfusion
Zuloaga, Kristen L; Johnson, Lance A; Roese, Natalie E; Marzulla, Tessa; Zhang, Wenri; Nie, Xiao; Alkayed, Farah N; Hong, Christine; Grafe, Marjorie R; Pike, Martin M; Raber, Jacob
2015-01-01
Diabetes causes endothelial dysfunction and increases the risk of vascular cognitive impairment. However, it is unknown whether diabetes causes cognitive impairment due to reductions in cerebral blood flow or through independent effects on neuronal function and cognition. We addressed this using right unilateral common carotid artery occlusion to model vascular cognitive impairment and long-term high-fat diet to model type 2 diabetes in mice. Cognition was assessed using novel object recognition task, Morris water maze, and contextual and cued fear conditioning. Cerebral blood flow was assessed using arterial spin labeling magnetic resonance imaging. Vascular cognitive impairment mice showed cognitive deficit in the novel object recognition task, decreased cerebral blood flow in the right hemisphere, and increased glial activation in white matter and hippocampus. Mice fed a high-fat diet displayed deficits in the novel object recognition task, Morris water maze and fear conditioning tasks and neuronal loss, but no impairments in cerebral blood flow. Compared to vascular cognitive impairment mice fed a low fat diet, vascular cognitive impairment mice fed a high-fat diet exhibited reduced cued fear memory, increased deficit in the Morris water maze, neuronal loss, glial activation, and global decrease in cerebral blood flow. We conclude that high-fat diet and chronic hypoperfusion impair cognitive function by different mechanisms, although they share commons features, and that high-fat diet exacerbates vascular cognitive impairment pathology. PMID:26661233
The Electric Field of a Weakly Electric Fish
NASA Astrophysics Data System (ADS)
Rasnow, Brian K.
Freshwater fish of the genus Apteronotus (family Gymnotidae) generate a weak, high frequency electric field (<100 mV/cm, 0.5-10 kHz) which permeates their local environment. These nocturnal fish are acutely sensitive to perturbations in their electric field caused by other electric fish, and nearby objects whose impedance is different from the surrounding water. This thesis presents high temporal and spatial resolution maps of the electric potential and field on and near Apteronotus. The fish's electric field is a complicated and highly stable function of space and time. Its characteristics, such as spectral composition, timing, and rate of attenuation, are examined in terms of physical constraints, and their possible functional roles in electroreception. Temporal jitter of the periodic field is less than 1 musec. However, electrocyte activity is not globally synchronous along the fish's electric organ. The propagation of electrocyte activation down the fish's body produces a rotation of the electric field vector in the caudal part of the fish. This may assist the fish in identifying nonsymmetrical objects, and could also confuse electrosensory predators that try to locate Apteronotus by following its fieldlines. The propagation also results in a complex spatiotemporal pattern of the EOD potential near the fish. Visualizing the potential on the same and different fish over timescales of several months suggests that it is stable and could serve as a unique signature for individual fish. Measurements of the electric field were used to calculate the effects of simple objects on the fish's electric field. The shape of the perturbation or "electric image" on the fish's skin is relatively independent of a simple object's size, conductivity, and rostrocaudal location, and therefore could unambiguously determine object distance. The range of electrolocation may depend on both the size of objects and their rostrocaudal location. Only objects with very large dielectric constants cause appreciable phase shifts, and these are strongly dependent on the water conductivity.
NASA Astrophysics Data System (ADS)
van Haveren, Rens; Ogryczak, Włodzimierz; Verduijn, Gerda M.; Keijzer, Marleen; Heijmen, Ben J. M.; Breedveld, Sebastiaan
2017-06-01
Previously, we have proposed Erasmus-iCycle, an algorithm for fully automated IMRT plan generation based on prioritised (lexicographic) multi-objective optimisation with the 2-phase ɛ-constraint (2pɛc) method. For each patient, the output of Erasmus-iCycle is a clinically favourable, Pareto optimal plan. The 2pɛc method uses a list of objective functions that are consecutively optimised, following a strict, user-defined prioritisation. The novel lexicographic reference point method (LRPM) is capable of solving multi-objective problems in a single optimisation, using a fuzzy prioritisation of the objectives. Trade-offs are made globally, aiming for large favourable gains for lower prioritised objectives at the cost of only slight degradations for higher prioritised objectives, or vice versa. In this study, the LRPM is validated for 15 head and neck cancer patients receiving bilateral neck irradiation. The generated plans using the LRPM are compared with the plans resulting from the 2pɛc method. Both methods were capable of automatically generating clinically relevant treatment plans for all patients. For some patients, the LRPM allowed large favourable gains in some treatment plan objectives at the cost of only small degradations for the others. Moreover, because of the applied single optimisation instead of multiple optimisations, the LRPM reduced the average computation time from 209.2 to 9.5 min, a speed-up factor of 22 relative to the 2pɛc method.
ERIC Educational Resources Information Center
DeFries, Ruth S., Ed.; Malone, Thomas F., Ed.
This volume of papers includes 21 of the 38 presentations given at the Forum on Global Change and Our Common Future. The objectives of the forum were threefold: (1) to present to the public a balanced and authoritative view of the wide range of global change issues, including the science of the earth system, the impacts of global change on…
NASA Astrophysics Data System (ADS)
Kawzenuk, B.; Sellars, S. L.; Nguyen, P.; Ralph, F. M.; Sorooshian, S.
2017-12-01
The CONNected objECT (CONNECT) algorithm is applied to Integrated Water Vapor Transport (IVT) data from the NASA's Modern-Era Retrospective Analysis for Research and Applications - Version 2 reanalysis product for the period 1980 to 2016 to study water vapor transport globally. The algorithm generates life-cycle records as statistical objects for the time and space location of the evolving strong vapor transport events. Global statistics are presented and used to investigate how climate variability impacts the events' location and frequency. Results show distinct water vapor object frequency and seasonal peaks during NH and SH Winter. Moreover, a positive linear trend in the annual number of objects is reported, increasing by 3.58 objects year-over-year (with 95% confidence, +/- 1.39). In addition, we show five distinct regions where these events typically exist (southeastern United States, eastern China, South Pacific south of 25°S, eastern South America and off the southern tip of South Africa), and where they rarely exist (eastern South Pacific Ocean and central southern Atlantic Ocean between 5°N-25°S). In addition, the event frequency and geographical location are also shown to be related to the Arctic Oscillation, Pacific North American Pattern, and the Quasi-Biennial Oscillation.
Neural markers of emotional face perception across psychotic disorders and general population.
Sabharwal, Amri; Kotov, Roman; Szekely, Akos; Leung, Hoi-Chung; Barch, Deanna M; Mohanty, Aprajita
2017-07-01
There is considerable variation in negative and positive symptoms of psychosis, global functioning, and emotional face perception (EFP), not only in schizophrenia but also in other psychotic disorders and healthy individuals. However, EFP impairment and its association with worse symptoms and global functioning have been examined largely in the domain of schizophrenia. The present study adopted a dimensional approach to examine the association of behavioral and neural measures of EFP with symptoms of psychosis and global functioning across individuals with schizophrenia spectrum (SZ; N = 28) and other psychotic (OP; N = 29) disorders, and never-psychotic participants (NP; N = 21). Behavioral and functional MRI data were recorded as participants matched emotional expressions of faces and geometrical shapes. Lower accuracy and increased activity in early visual regions, hippocampus, and amygdala during emotion versus shape matching were associated with higher negative, but not positive, symptoms and lower global functioning, across all participants. This association remained even after controlling for group-related (SZ, OP, and NP) variance, dysphoria, and antipsychotic medication status, except in amygdala. Furthermore, negative symptoms mediated the relationship between behavioral and brain EFP measures and global functioning. This study provides some of the first evidence supporting the specific relationship of EFP measures with negative symptoms and global functioning across psychotic and never-psychotic samples, and transdiagnostically across different psychotic disorders. Present findings help bridge the gap between basic EFP-related neuroscience research and clinical research in psychosis, and highlight EFP as a potential symptom-specific marker that tracks global functioning. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
A Multi-Objective Decision Making Approach for Solving the Image Segmentation Fusion Problem.
Khelifi, Lazhar; Mignotte, Max
2017-08-01
Image segmentation fusion is defined as the set of methods which aim at merging several image segmentations, in a manner that takes full advantage of the complementarity of each one. Previous relevant researches in this field have been impeded by the difficulty in identifying an appropriate single segmentation fusion criterion, providing the best possible, i.e., the more informative, result of fusion. In this paper, we propose a new model of image segmentation fusion based on multi-objective optimization which can mitigate this problem, to obtain a final improved result of segmentation. Our fusion framework incorporates the dominance concept in order to efficiently combine and optimize two complementary segmentation criteria, namely, the global consistency error and the F-measure (precision-recall) criterion. To this end, we present a hierarchical and efficient way to optimize the multi-objective consensus energy function related to this fusion model, which exploits a simple and deterministic iterative relaxation strategy combining the different image segments. This step is followed by a decision making task based on the so-called "technique for order performance by similarity to ideal solution". Results obtained on two publicly available databases with manual ground truth segmentations clearly show that our multi-objective energy-based model gives better results than the classical mono-objective one.
NASA Astrophysics Data System (ADS)
Wu, J.; Yang, Y.; Luo, Q.; Wu, J.
2012-12-01
This study presents a new hybrid multi-objective evolutionary algorithm, the niched Pareto tabu search combined with a genetic algorithm (NPTSGA), whereby the global search ability of niched Pareto tabu search (NPTS) is improved by the diversification of candidate solutions arose from the evolving nondominated sorting genetic algorithm II (NSGA-II) population. Also, the NPTSGA coupled with the commonly used groundwater flow and transport codes, MODFLOW and MT3DMS, is developed for multi-objective optimal design of groundwater remediation systems. The proposed methodology is then applied to a large-scale field groundwater remediation system for cleanup of large trichloroethylene (TCE) plume at the Massachusetts Military Reservation (MMR) in Cape Cod, Massachusetts. Furthermore, a master-slave (MS) parallelization scheme based on the Message Passing Interface (MPI) is incorporated into the NPTSGA to implement objective function evaluations in distributed processor environment, which can greatly improve the efficiency of the NPTSGA in finding Pareto-optimal solutions to the real-world application. This study shows that the MS parallel NPTSGA in comparison with the original NPTS and NSGA-II can balance the tradeoff between diversity and optimality of solutions during the search process and is an efficient and effective tool for optimizing the multi-objective design of groundwater remediation systems under complicated hydrogeologic conditions.
Bias effects in the possible/impossible object decision test with matching objects.
Soldan, Anja; Hilton, H John; Stern, Yaakov
2009-03-01
In the possible/impossible object decision test, priming has consistently been found for structurally possible, but not impossible, objects, leading Schacter, Cooper, and Delaney (1990) to suggest that priming relies on a system that represents the global 3-D structure of objects. Using a modified design with matching objects to control for the influence of episodic memory, Ratcliff and McKoon (1995) and Williams and Tarr (1997) found negative priming for impossible objects (i.e., lower performance for old than for new items). Both teams argued that priming derives from (1) episodic memory for object features and (2) bias to respond "possible" to encoded objects or their possible parts. The present study applied the matched-objects design to the original Schacter and Cooper stimuli-same possible objects and matching impossible figures-with minimal procedural variation. The data from Experiment 1 only partially supported the bias models and suggested that priming was mediated by both local and global structural descriptions. Experiment 2 showed that negative priming for impossible objects derived from the structural properties of these objects, not from the influence of episodic memory on task performance. Supplemental materials for this study may be downloaded from mc.psychonomic-journals.org/content/supplemental.
Dettinger, Julia; Calkins, Kimberly; Kibore, Minnie; Gachuno, Onesmus; Walker, Dilys
2018-01-01
Background Globally, the rate of reduction in delivery-associated maternal and perinatal mortality has been slow compared to improvements in post-delivery mortality in children under five. Improving clinical readiness for basic obstetric emergencies is crucial for reducing facility-based maternal deaths. Emergency readiness is commonly assessed using tracers derived from the maternal signal functions model. Objective-method We compare emergency readiness using the signal functions model and a novel clinical cascade. The cascades model readiness as the proportion of facilities with resources to identify the emergency (stage 1), treat it (stage 2) and monitor-modify therapy (stage 3). Data were collected from 44 Kenyan clinics as part of an implementation trial. Findings Although most facilities (77.0%) stock maternal signal function tracer drugs, far fewer have resources to practically identify and treat emergencies. In hypertensive emergencies for example, 38.6% of facilities have resources to identify the emergency (Stage 1 readiness, including sphygmomanometer, stethoscope, urine collection device, protein test). 6.8% have the resources to treat the emergency (Stage 2, consumables (IV Kit, fluids), durable goods (IV pole) and drugs (magnesium sulfate and hydralazine). No facilities could monitor or modify therapy (Stage 3). Across five maternal emergencies, the signal functions overestimate readiness by 54.5%. A consistent, step-wise pattern of readiness loss across signal functions and care stage emerged and was profoundly consistent at 33.0%. Significance Comparing estimates from the maternal signal functions and cascades illustrates four themes. First, signal functions overestimate practical readiness by 55%. Second, the cascade’s intuitive indicators can support cross-sector health system or program planners to more precisely measure and improve emergency care. Third, adding few variables to existing readiness inventories permits step-wise modeling of readiness loss and can inform more precise interventions. Fourth, the novel aggregate readiness loss indicator provides an innovative and intuitive approach for modeling health system emergency readiness. Additional testing in diverse contexts is warranted. PMID:29474397
Robust expertise effects in right FFA
McGugin, Rankin Williams; Newton, Allen T; Gore, John C; Gauthier, Isabel
2015-01-01
The fusiform face area (FFA) is one of several areas in occipito-temporal cortex whose activity is correlated with perceptual expertise for objects. Here, we investigate the robustness of expertise effects in FFA and other areas to a strong task manipulation that increases both perceptual and attentional demands. With high-resolution fMRI at 7Telsa, we measured responses to images of cars, faces and a category globally visually similar to cars (sofas) in 26 subjects who varied in expertise with cars, in (a) a low load 1-back task with a single object category and (b) a high load task in which objects from two categories rapidly alternated and attention was required to both categories. The low load condition revealed several areas more active as a function of expertise, including both posterior and anterior portions of FFA bilaterally (FFA1/FFA2 respectively). Under high load, fewer areas were positively correlated with expertise and several areas were even negatively correlated, but the expertise effect in face-selective voxels in the anterior portion of FFA (FFA2) remained robust. Finally, we found that behavioral car expertise also predicted increased responses to sofa images but no behavioral advantages in sofa discrimination, suggesting that global shape similarity to a category of expertise is enough to elicit a response in FFA and other areas sensitive to experience, even when the category itself is not of special interest. The robustness of expertise effects in right FFA2 and the expertise effects driven by visual similarity both argue against attention being the sole determinant of expertise effects in extrastriate areas. PMID:25192631
How to perform Subjective Global Nutritional assessment in children.
Secker, Donna J; Jeejeebhoy, Khursheed N
2012-03-01
Subjective Global Assessment (SGA) is a method for evaluating nutritional status based on a practitioner's clinical judgment rather than objective, quantitative measurements. Encompassing historical, symptomatic, and physical parameters, SGA aims to identify an individual's initial nutrition state and consider the interplay of factors influencing the progression or regression of nutrition abnormalities. SGA has been widely used for more than 25 years to assess the nutritional status of adults in both clinical and research settings. Perceiving multiple benefits of its use in children, we recently adapted and validated the SGA tool for use in a pediatric population, demonstrating its ability to identify the nutritional status of children undergoing surgery and their risk of developing nutrition-associated complications postoperatively. Objective measures of nutritional status, on the other hand, showed no association with outcomes. The purpose of this article is to describe in detail the methods used in conducting nutrition-focused physical examinations and the medical history components of a pediatric Subjective Global Nutritional Assessment tool. Guidelines are given for performing and interpreting physical examinations that look for evidence of loss of subcutaneous fat, muscle wasting, and/or edema in children of different ages. Age-related questionnaires are offered to guide history taking and the rating of growth, weight changes, dietary intake, gastrointestinal symptoms, functional capacity, and any metabolic stress. Finally, the associated rating form is provided, along with direction for how to consider all components of a physical exam and history in the context of each other, to assign an overall rating of normal/well nourished, moderate malnutrition, or severe malnutrition. With this information, interested health professionals will be able to perform Subjective Global Nutritional Assessment to determine a global rating of nutritional status for infants, children, and adolescents, and use this rating to guide decision making about what nutrition-related attention is necessary. Dietetics practitioners and other clinicians are encouraged to incorporate physical examination for signs of protein-energy depletion when assessing the nutritional status of children. Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.
In situ structure and dynamics of DNA origami determined through molecular dynamics simulations
Yoo, Jejoong; Aksimentiev, Aleksei
2013-01-01
The DNA origami method permits folding of long single-stranded DNA into complex 3D structures with subnanometer precision. Transmission electron microscopy, atomic force microscopy, and recently cryo-EM tomography have been used to characterize the properties of such DNA origami objects, however their microscopic structures and dynamics have remained unknown. Here, we report the results of all-atom molecular dynamics simulations that characterized the structural and mechanical properties of DNA origami objects in unprecedented microscopic detail. When simulated in an aqueous environment, the structures of DNA origami objects depart from their idealized targets as a result of steric, electrostatic, and solvent-mediated forces. Whereas the global structural features of such relaxed conformations conform to the target designs, local deformations are abundant and vary in magnitude along the structures. In contrast to their free-solution conformation, the Holliday junctions in the DNA origami structures adopt a left-handed antiparallel conformation. We find the DNA origami structures undergo considerable temporal fluctuations on both local and global scales. Analysis of such structural fluctuations reveals the local mechanical properties of the DNA origami objects. The lattice type of the structures considerably affects global mechanical properties such as bending rigidity. Our study demonstrates the potential of all-atom molecular dynamics simulations to play a considerable role in future development of the DNA origami field by providing accurate, quantitative assessment of local and global structural and mechanical properties of DNA origami objects. PMID:24277840
In situ structure and dynamics of DNA origami determined through molecular dynamics simulations.
Yoo, Jejoong; Aksimentiev, Aleksei
2013-12-10
The DNA origami method permits folding of long single-stranded DNA into complex 3D structures with subnanometer precision. Transmission electron microscopy, atomic force microscopy, and recently cryo-EM tomography have been used to characterize the properties of such DNA origami objects, however their microscopic structures and dynamics have remained unknown. Here, we report the results of all-atom molecular dynamics simulations that characterized the structural and mechanical properties of DNA origami objects in unprecedented microscopic detail. When simulated in an aqueous environment, the structures of DNA origami objects depart from their idealized targets as a result of steric, electrostatic, and solvent-mediated forces. Whereas the global structural features of such relaxed conformations conform to the target designs, local deformations are abundant and vary in magnitude along the structures. In contrast to their free-solution conformation, the Holliday junctions in the DNA origami structures adopt a left-handed antiparallel conformation. We find the DNA origami structures undergo considerable temporal fluctuations on both local and global scales. Analysis of such structural fluctuations reveals the local mechanical properties of the DNA origami objects. The lattice type of the structures considerably affects global mechanical properties such as bending rigidity. Our study demonstrates the potential of all-atom molecular dynamics simulations to play a considerable role in future development of the DNA origami field by providing accurate, quantitative assessment of local and global structural and mechanical properties of DNA origami objects.
E-Learning and Lifelong Learning
ERIC Educational Resources Information Center
Mouzakitis, George S.; Tuncay, Nazime
2011-01-01
It is supported that the object of education is to provide results. Hence, it is of crucial importance to economic development globally. In our era, globalization is a highly disputable event with strong persuasive arguments and equally solid disagreements. The impact of globalization in our everyday activities has been increased. In parallel,…
Validity of prototype diagnosis for mood and anxiety disorders.
DeFife, Jared A; Peart, Joanne; Bradley, Bekh; Ressler, Kerry; Drill, Rebecca; Westen, Drew
2013-02-01
CONTEXT With growing recognition that most forms of psychopathology are best represented as dimensions or spectra, a central question becomes how to implement dimensional diagnosis in a way that is empirically sound and clinically useful. Prototype matching, which involves comparing a patient's clinical presentation with a prototypical description of the disorder, is an approach to diagnosis that has gained increasing attention with forthcoming revisions to both the DSM and the International Classification of Diseases. OBJECTIVE To examine prototype diagnosis for mood and anxiety disorders. DESIGN, SETTING, AND PATIENTS In the first study, we examined clinicians' DSM-IV and prototype diagnoses with their ratings of the patients' adaptive functioning and patients' self-reported symptoms. In the second study, independent interviewers made prototype diagnoses following either a systematic clinical interview or a structured diagnostic interview. A third interviewer provided independent ratings of global adaptive functioning. Patients were recruited as outpatients (study 1; N = 84) and from primary care clinics (study 2; N = 143). MAIN OUTCOME MEASURES Patients' self-reported mood, anxiety, and externalizing symptoms along with independent clinical ratings of adaptive functioning. RESULTS Clinicians' prototype diagnoses showed small to moderate correlations with patient-reported psychopathology and performed as well as or better than DSM-IV diagnoses. Prototype diagnoses from independent interviewers correlated on average r = .50 and showed substantial incremental validity over DSM-IV diagnoses in predicting adaptive functioning. CONCLUSIONS Prototype matching is a viable alternative for psychiatric diagnosis. As in research on personality disorders, mood and anxiety disorder prototypes outperformed DSM-IV decision rules in predicting psychopathology and global functioning. Prototype matching has multiple advantages, including ease of use in clinical practice, reduced artifactual comorbidity, compatibility with naturally occurring cognitive processes in diagnosticians, and ready translation into both categorical and dimensional diagnosis.
Using simple environmental variables to estimate below-ground productivity in grasslands
Gill, R.A.; Kelly, R.H.; Parton, W.J.; Day, K.A.; Jackson, R.B.; Morgan, J.A.; Scurlock, J.M.O.; Tieszen, L.L.; Castle, J.V.; Ojima, D.S.; Zhang, X.S.
2002-01-01
In many temperate and annual grasslands, above-ground net primary productivity (NPP) can be estimated by measuring peak above-ground biomass. Estimates of below-ground net primary productivity and, consequently, total net primary productivity, are more difficult. We addressed one of the three main objectives of the Global Primary Productivity Data Initiative for grassland systems to develop simple models or algorithms to estimate missing components of total system NPP. Any estimate of below-ground NPP (BNPP) requires an accounting of total root biomass, the percentage of living biomass and annual turnover of live roots. We derived a relationship using above-ground peak biomass and mean annual temperature as predictors of below-ground biomass (r2 = 0.54; P = 0.01). The percentage of live material was 0.6, based on published values. We used three different functions to describe root turnover: constant, a direct function of above-ground biomass, or as a positive exponential relationship with mean annual temperature. We tested the various models against a large database of global grassland NPP and the constant turnover and direct function models were approximately equally descriptive (r2 = 0.31 and 0.37), while the exponential function had a stronger correlation with the measured values (r2 = 0.40) and had a better fit than the other two models at the productive end of the BNPP gradient. When applied to extensive data we assembled from two grassland sites with reliable estimates of total NPP, the direct function was most effective, especially at lower productivity sites. We provide some caveats for its use in systems that lie at the extremes of the grassland gradient and stress that there are large uncertainties associated with measured and modelled estimates of BNPP.
Groeger, John A.; Stanley, Neil; Deacon, Stephen; Dijk, Derk-Jan
2014-01-01
Study Objective: To contrast the effects of slow wave sleep (SWS) disruption and age on daytime functioning. Design: Daytime functioning was contrasted in three age cohorts, across two parallel 4-night randomized groups (baseline, two nights of SWS disruption or control, recovery sleep). Setting: Sleep research laboratory. Participants: 44 healthy young (20-30 y), 35 middle-aged (40-55 y), and 31 older (66-83 y) men and women. Interventions: Acoustic stimulation contingent on appearance of slow waves. Measurements and Results: Cognitive performance was assessed before sleep latency tests at five daily time-points. SWS disruption resulted in less positive affect, slower or impaired information processing and sustained attention, less precise motor control, and erroneous implementation, rather than inhibition, of well-practiced actions. These performance impairments had far smaller effect sizes than the increase in daytime sleepiness and differed from baseline to the same extent for each age group. At baseline, younger participants performed better than older participants across many cognitive domains, with largest effects on executive function, response time, sustained attention, and motor control. At baseline, the young were sleepier than other age groups. Conclusions: SWS has been considered a potential mediator of age-related decline in performance, although the effects of SWS disruption on daytime functioning have not been quantified across different cognitive domains nor directly compared to age-related changes in performance. The data imply that two nights of SWS disruption primarily leads to an increase in sleepiness with minor effects on other aspects of daytime functioning, which are different from the substantial effects of age. Citation: Groeger JA, Stanley N, Deacon S, Dijk DJ. Dissociating effects of global sws disruption and healthy aging on waking performance and daytime sleepiness. SLEEP 2014;37(6):1127-1142. PMID:24882908
Althof, Stanley E; O' Leary, Michael P; Cappelleri, Joseph C; Glina, Sidney; King, Rosie; Tseng, Li-Jung; Bowler, Jessica L
2006-01-01
BACKGROUND Men with erectile dysfunction (ED) often have low self-esteem, confidence, and sexual relationship satisfaction. OBJECTIVE We evaluated the impact of sildenafil citrate and its generalizability across cultures on self-esteem, confidence, and sexual relationship satisfaction in men with ED using the Self-Esteem And Relationship (SEAR) questionnaire. DESIGN Pooled analysis of 2 double-blind, placebo-controlled, flexible-dose trials of sildenafil with identical protocols: 1 was conducted in the United States and the other in Mexico, Brazil, Australia, and Japan. PATIENTS Men ≥18 years old with ED. MEASUREMENTS The impact of treatment on psychosocial factors associated with ED was determined by patient responses to the SEAR questionnaire. Erectile function was determined using the International Index of Erectile Function (IIEF) and a global efficacy question. Successful sexual intercourse attempts were derived from event logs of sexual activity. Treatment effect sizes were calculated for all study outcomes. RESULTS Compared with patients who received placebo (n = 274), patients who received sildenafil (n = 279) reported significantly greater improvements (P<.0001) in self-esteem, confidence, sexual relationship satisfaction, and in all sexual function domains of the IIEF. Treatment effect sizes were large (range, 0.7 to 1.2) for all SEAR components, and improvement in psychosocial measures showed moderate to high correlations (range, 0.50 to 0.83, P<.0001) with improvement in erectile function, percentage of successful intercourse attempts, and global efficacy. CONCLUSIONS In men with ED from 5 different nations, sildenafil produced substantial improvements in self-esteem, confidence, and sexual relationship satisfaction. Improvements in these psychosocial factors were observed crossculturally and correlated significantly and tangibly with improvements in erectile function. PMID:16836626
Zhao, Meng; Ding, Baocang
2015-03-01
This paper considers the distributed model predictive control (MPC) of nonlinear large-scale systems with dynamically decoupled subsystems. According to the coupled state in the overall cost function of centralized MPC, the neighbors are confirmed and fixed for each subsystem, and the overall objective function is disassembled into each local optimization. In order to guarantee the closed-loop stability of distributed MPC algorithm, the overall compatibility constraint for centralized MPC algorithm is decomposed into each local controller. The communication between each subsystem and its neighbors is relatively low, only the current states before optimization and the optimized input variables after optimization are being transferred. For each local controller, the quasi-infinite horizon MPC algorithm is adopted, and the global closed-loop system is proven to be exponentially stable. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.
Lechner, Matthias; Steirer, Iva; Brinkhaus, Benno; Chen, Yun; Krist-Dungl, Claudia; Koschier, Alexandra; Gantschacher, Martina; Neumann, Kurt; Zauner-Dungl, Andrea
2011-06-01
The objective of this study was to determine the efficacy of individually designed herbal formulas according to the rules of Traditional Chinese Medicine (TCM) in patients with osteoarthritis of the hip and knee. This was a randomized, controlled, double-blind study with two parallel groups. This study was conducted at the University-centre in Gars am Kamp/Austria and was organized by the Institute of TCM and Complementary Medicine of the Danube University Krems /Austria. The study comprised female and male patients with osteoarthritis of hip or knee aged between 45 and 75 years. Patients were randomized into a treatment with individualized, water-based herbal decoctions prepared in a standardized cooking process (Verum group) or to a treatment with nonspecific presumably ineffective, water-based herbal decoctions (Control group). The primary outcome was the comparison of change between the intervention groups in the Western Ontario and McMaster Universities lower limb global index questionnaire (WOMAC global index) between baseline and week 20. Secondary outcomes included subscales of WOMAC for pain (A), stiffness (B), and functional impairment (C) and general quality of life in the form of the SF-36 questionnaire. Altogether, 102 patients were randomized in this trial. The demographic and medical baseline characteristics were comparable in the 2 groups. The change of the WOMAC global index and all three subscales was significant in both groups between week 20 and baseline (verum group, global WOMAC: at baseline 47 [SD ± 11.8] and at week 20: 24 (SD ± 18.3); change of mean 23; p > 0.001; control group; global WOMAC: at baseline: 48 (SD ± 14.7) and at week 20: 25 (SD ± 18.3); change of mean 23; p > 0.001). However, there was no significant difference (p = 0.783) between the treatment groups. There were significant changes in the subscales "physical functioning," "bodily pain," "vitality," "social-functioning," and "role-physical" of the SF-36 in both study groups between 20 weeks and baseline, but again no significant difference between the groups. There were no drug-related serious adverse events. While the individual prescription consisting of medicinal herbs according to TCM diagnosis investigated in this trial tend to improve the osteoarthritis, the same effect was also achieved with the nonspecific prescription.
Kruschwitz, J D; Waller, L; Daedelow, L S; Walter, H; Veer, I M
2018-05-01
One hallmark example of a link between global topological network properties of complex functional brain connectivity and cognitive performance is the finding that general intelligence may depend on the efficiency of the brain's intrinsic functional network architecture. However, although this association has been featured prominently over the course of the last decade, the empirical basis for this broad association of general intelligence and global functional network efficiency is quite limited. In the current study, we set out to replicate the previously reported association between general intelligence and global functional network efficiency using the large sample size and high quality data of the Human Connectome Project, and extended the original study by testing for separate association of crystallized and fluid intelligence with global efficiency, characteristic path length, and global clustering coefficient. We were unable to provide evidence for the proposed association between general intelligence and functional brain network efficiency, as was demonstrated by van den Heuvel et al. (2009), or for any other association with the global network measures employed. More specifically, across multiple network definition schemes, ranging from voxel-level networks to networks of only 100 nodes, no robust associations and only very weak non-significant effects with a maximal R 2 of 0.01 could be observed. Notably, the strongest (non-significant) effects were observed in voxel-level networks. We discuss the possibility that the low power of previous studies and publication bias may have led to false positive results fostering the widely accepted notion of general intelligence being associated to functional global network efficiency. Copyright © 2018 Elsevier Inc. All rights reserved.
Erdoğan, Sinem B; Tong, Yunjie; Hocke, Lia M; Lindsey, Kimberly P; deB Frederick, Blaise
2016-01-01
Resting state functional connectivity analysis is a widely used method for mapping intrinsic functional organization of the brain. Global signal regression (GSR) is commonly employed for removing systemic global variance from resting state BOLD-fMRI data; however, recent studies have demonstrated that GSR may introduce spurious negative correlations within and between functional networks, calling into question the meaning of anticorrelations reported between some networks. In the present study, we propose that global signal from resting state fMRI is composed primarily of systemic low frequency oscillations (sLFOs) that propagate with cerebral blood circulation throughout the brain. We introduce a novel systemic noise removal strategy for resting state fMRI data, "dynamic global signal regression" (dGSR), which applies a voxel-specific optimal time delay to the global signal prior to regression from voxel-wise time series. We test our hypothesis on two functional systems that are suggested to be intrinsically organized into anticorrelated networks: the default mode network (DMN) and task positive network (TPN). We evaluate the efficacy of dGSR and compare its performance with the conventional "static" global regression (sGSR) method in terms of (i) explaining systemic variance in the data and (ii) enhancing specificity and sensitivity of functional connectivity measures. dGSR increases the amount of BOLD signal variance being modeled and removed relative to sGSR while reducing spurious negative correlations introduced in reference regions by sGSR, and attenuating inflated positive connectivity measures. We conclude that incorporating time delay information for sLFOs into global noise removal strategies is of crucial importance for optimal noise removal from resting state functional connectivity maps.
Toward Balance Recovery With Leg Prostheses Using Neuromuscular Model Control
Geyer, Hartmut
2016-01-01
Objective Lower limb amputees are at high risk of falling as current prosthetic legs provide only limited functionality for recovering balance after unexpected disturbances. For instance, the most established control method used on powered leg prostheses tracks local joint impedance functions without taking the global function of the leg in balance recovery into account. Here we explore an alternative control policy for powered transfemoral prostheses that considers the global leg function and is based on a neuromuscular model of human locomotion. Methods We adapt this model to describe and simulate an amputee walking with a powered prosthesis using the proposed control, and evaluate the gait robustness when confronted with rough ground and swing leg disturbances. We then implement and partially evaluate the resulting controller on a leg prosthesis prototype worn by a non-amputee user. Results In simulation, the proposed prosthesis control leads to gaits that are more robust than those obtained by the impedance control method. The initial hardware experiments with the prosthesis prototype show that the proposed control reproduces normal walking patterns qualitatively and effectively responds to disturbances in early and late swing. However, the response to mid-swing disturbances neither replicates human responses nor averts falls. Conclusions The neuromuscular model control is a promising alternative to existing prosthesis controls, although further research will need to improve on the initial implementation and determine how well these results transfer to amputee gait. Significance This work provides a potential avenue for future development of control policies that help improve amputee balance recovery. PMID:26315935
Seo, Eun Hyun; Kim, Hoowon; Choi, Kyu Yeong; Lee, Kun Ho; Choo, Il Han
2017-08-01
Subjective memory complaints (SMC) and depressive symptoms (SDS) are common in the elderly population. However, the relationship among SMC, SDS, and cognitive function remains unclear. We investigated these associations in the elderly from cognitively normal (CN), pre-mild cognitive impairment (MCI), and amnestic MCI (aMCI) groups. Participants (CN, 299; pre-MCI, 106; aMCI, 267) underwent comprehensive clinical and neuropsychological assessment. and self-report SMC and SDS questionnaires. SMC and SDS were administered in a self-report format. For each neuropsychological test z-score, stepwise multiple linear regressions were performed to assess the relative contribution of SMC, SDS, and their interactions. SMC are associated with lower objective memory, while SDS are associated with lower psychomotor speed. Interactions between SMC and SDS were significant for tests of memory, executive function, psychomotor speed, and global cognition. Additional analyses revealed that SDS moderated the SMC-cognition relationship such that only individuals with higher SDS showed significant SMC-cognition associations. Due to the cross-sectional design, associations among SMC, SDS, and cognitive function was rather weak, albeit significant. Additionally, future biomarker studies, such as those assessing amyloid burden, are needed to explore the mechanisms underlying the relationship among SMC, SDS, and cognitive function. Early identification of individuals at risk for developing abnormal cognitive changes is critical. Our findings from the study involving a large sample of carefully selected participants suggest that SMC and SDS could be used as early detection markers of Alzheimer's disease. Copyright © 2017. Published by Elsevier B.V.
ERIC Educational Resources Information Center
Jubas, Kaela
2005-01-01
Globalization continues to interest researchers and practitioners as it unfolds around us. This article contributes to the analysis of globalization's discourse, objectives and outcomes, by exploring the impact of globalization on community and its implications for adult learning. Using selected themes from a work of fiction to frame this…
Automated micromanipulation desktop station based on mobile piezoelectric microrobots
NASA Astrophysics Data System (ADS)
Fatikow, Sergej
1996-12-01
One of the main problems of present-day research on microsystem technology (MST) is to assemble a whole micro- system from different microcomponents. This paper presents a new concept of an automated micromanipulation desktop- station including piezoelectrically driven microrobots placed on a high-precise x-y-stage of a light microscope, a CCD-camera as a local sensor subsystem, a laser sensor unit as a global sensor subsystem, a parallel computer system with C167 microcontrollers, and a Pentium PC equipped additionally with an optical grabber. The microrobots can perform high-precise manipulations (with an accuracy of up to 10 nm) and a nondestructive transport (at a speed of about 3 cm/sec) of very small objects under the microscope. To control the desktop-station automatically, an advanced control system that includes a task planning level and a real-time execution level is being developed. The main function of the task planning sub-system is to interpret the implicit action plan and to generate a sequence of explicit operations which are sent to the execution level of the control system. The main functions of the execution control level are the object recognition, image processing and feedback position control of the microrobot and the microscope stage.
Calibration of DEM parameters on shear test experiments using Kriging method
NASA Astrophysics Data System (ADS)
Bednarek, Xavier; Martin, Sylvain; Ndiaye, Abibatou; Peres, Véronique; Bonnefoy, Olivier
2017-06-01
Calibration of powder mixing simulation using Discrete-Element-Method is still an issue. Achieving good agreement with experimental results is difficult because time-efficient use of DEM involves strong assumptions. This work presents a methodology to calibrate DEM parameters using Efficient Global Optimization (EGO) algorithm based on Kriging interpolation method. Classical shear test experiments are used as calibration experiments. The calibration is made on two parameters - Young modulus and friction coefficient. The determination of the minimal number of grains that has to be used is a critical step. Simulations of a too small amount of grains would indeed not represent the realistic behavior of powder when using huge amout of grains will be strongly time consuming. The optimization goal is the minimization of the objective function which is the distance between simulated and measured behaviors. The EGO algorithm uses the maximization of the Expected Improvement criterion to find next point that has to be simulated. This stochastic criterion handles with the two interpolations made by the Kriging method : prediction of the objective function and estimation of the error made. It is thus able to quantify the improvement in the minimization that new simulations at specified DEM parameters would lead to.
Most-Critical Transient Disturbances in an Incompressible Flat-Plate Boundary Layer
NASA Astrophysics Data System (ADS)
Monschke, Jason; White, Edward
2015-11-01
Transient growth is a linear disturbance growth mechanism that plays a key role in roughness-induced boundary-layer transition. It occurs when superposed stable, non-orthogonal continuous spectrum modes experience algebraic disturbance growth followed by exponential decay. Algebraic disturbance growth can modify the basic state making it susceptible to secondary instabilities rapidly leading to transition. Optimal disturbance theory was developed to model the most-dangerous disturbances. However, evidence suggests roughness-induced transient growth is sub-optimal yet leads to transition earlier than optimal theory suggests. This research computes initial disturbances most unstable to secondary instabilities to further develop the applicability of transient growth theory to surface roughness. The main approach is using nonlinear adjoint optimization with solutions of the parabolized Navier-Stokes and BiGlobal stability equations. Two objective functions were considered: disturbance kinetic energy growth and sinuous instability growth rate. The first objective function was used as validation of the optimization method. Counter-rotating streamwise vortices located low in the boundary layer maximize the sinuous instability growth rate. The authors would like to acknowledge NASA and the AFOSR for funding this work through AFOSR Grant FA9550-09-1-0341.
Alvarez-Segura, T; Gómez-Díaz, A; Ortiz-Bolsico, C; Torres-Lapasió, J R; García-Alvarez-Coque, M C
2015-08-28
Getting useful chemical information from samples containing many compounds is still a challenge to analysts in liquid chromatography. The highest complexity corresponds to samples for which there is no prior knowledge about their chemical composition. Computer-based methodologies are currently considered as the most efficient tools to optimise the chromatographic resolution, and further finding the optimal separation conditions. However, most chromatographic objective functions (COFs) described in the literature to measure the resolution are based on mathematical models fitted with the information obtained from standards, and cannot be applied to samples with unknown compounds. In this work, a new COF based on the automatic measurement of the protruding part of the chromatographic peaks (or peak prominences) that indicates the number of perceptible peaks and global resolution, without the need of standards, is developed. The proposed COF was found satisfactory with regard to the peak purity criterion when applied to artificial peaks and simulated chromatograms of mixtures built using the information of standards. The approach was applied to mixtures of drugs containing unknown impurities and degradation products and to extracts of medicinal herbs, eluted with acetonitrile-water mixtures using isocratic and gradient elution. Copyright © 2015 Elsevier B.V. All rights reserved.
Høglend, Per; Amlo, Svein; Marble, Alice; Bøgwald, Kjell-Petter; Sørbye, Oystein; Sjaastad, Mary Cosgrove; Heyerdahl, Oscar
2006-10-01
The purpose of this study was to measure the effects of transference interpretations (the assumed core active ingredient) in dynamic psychotherapy, using an experimental design. One hundred patients were randomly assigned to two groups. One group received dynamic psychotherapy over 1 year, with a moderate level of transference interpretations, while the other group received dynamic psychotherapy with no transference interpretations. The most common axis I disorders were depression and anxiety disorders. Forty-six patients fulfilled the general criteria for personality disorder. Seven experienced psychotherapists treated patients in both groups. Five full sessions from each treatment were rated by two evaluators with process measures in order to document treatment integrity. Outcome variables were the Psychodynamic Functioning Scales, Inventory of Interpersonal Problems Scale-Circumplex version, Global Assessment of Functioning Scale, and Symptom Checklist-90-R. Quality of Object Relations Scale (lifelong pattern) and personality disorders were preselected as possible moderators of treatment effects. Change was assessed using linear-mixed models. Clinically significant change was also calculated. The authors could not demonstrate differential treatment effects between the groups. However, the moderator analyses showed that transference interpretations were more helpful for patients with a lifelong history of less mature object relations. Small negative effects were observed for patients with mature object relations. The authors could not show differences in average effectiveness between treatments. However, the moderator analyses indicated that treatment worked through different active ingredients for different patients. Contrary to common expectation, patients with poor object relations profited more from therapy with transference interpretations than from therapy with no transference interpretations.
Fibromyalgia Syndrome Module at OMERACT 9
Mease, Philip; Arnold, Lesley M; Choy, Ernest H; Clauw, Daniel J.; Crofford, Leslie; Glass, Jennifer M; Martin, Susan A; Morea, Jessica; Simon, Lee; Strand, Vibeke; Williams, David A
2012-01-01
Objectives (1) Establish a core domain set for fibromyalgia (FM) assessment in clinical trials and practice, (2) review outcome measures’ performance characteristics, (3) discuss development of a responder index for the assessment of FM in clinical trials, (4) review objective markers, (5) review the domain of cognitive dysfunction, (6) establish a research agenda for work regarding outcomes research. Methods (1) Results of univariate and multivariate analysis of 10 different FM clinical trials of four different drugs, mapping key domains identified in previously presented patient focus group: Delphi exercises and a clinician/researcher Delphi exercise, breakout discussions to vote on possible essential domains and reliable measures. (2) Updates presented regarding outcome measures’ status. (3) Presented update on objective markers to measure FM disease state. 4) The issue of cognitive dysfunction (dyscognition) in FM was reviewed. Results (1) Greater than 70% of OMERACT participants agreed that pain, tenderness, fatigue, patient global, multidimensional function and sleep disturbance domains should be measured in all FM clinical trials, dyscognition and depression in some trial, and domains of research interest include stiffness, anxiety, functional imaging, and cerebrospinal fluid biomarkers. (2) FM domains’ outcome measures have generally proven to be reliable, discriminative, and feasible. More sophisticated and comprehensive measures are in development, as is a responder index for FM. (3) Increasing number of objective markers are being developed for FM assessment. (4) Cognitive dysfunction assessment by self-assessed and applied outcome measures is being developed. Conclusions A multidimensional symptom core set is proposed for the evaluation of FM in clinical trials. There is ongoing research on improved measures of single domains and composite measures. PMID:19820221
Which factors are associated with global cognitive impairment in Wilson's disease?
Frota, Norberto Anízio Ferreira; Barbosa, Egberto Reis; Porto, Claudia Sellitto; Lucato, Leandro Tavares; Ono, Carla Rachel; Buchpiguel, Carlos Alberto; Machado, Alexandre Aluizio Costa; Caramelli, Paulo
2016-01-01
Background Patients with Wilson's disease (WD) present cognitive impairment, especially in executive functions. Which other factors might be associated with global cognitive decline in these patients remains unclear. Objective To assess which factors are associated with worse performance on a global cognitive test in patients with WD. Methods Twenty patients with WD underwent cognitive assessment with the following tests: the Mini-Mental State Examination (MMSE), Dementia Rating Scale (DRS), verbal fluency test, brief cognitive battery, clock drawing test, Frontal Assessment Battery, Stroop test, Wisconsin card sorting test, Hopper test, cubes (WAIS) and the Pfeffer questionnaire. MRI changes were quantified. Patients with poor performance on the DRS were compared to patients with normal performance. Results Nine patients had a poor performance on the DRS. This group had lower educational level (9.11±3.58× 12.82±3.06) and a greater number of changes on MRI (9.44±2.74× 6.27±2.45). The presence of hyperintensity in the globus pallidus on MRI was more frequent in this group (66.6% vs 9.0%), with OR=5.38 (95% CI 0.85-33.86). Conclusion Global cognitive impairment was prevalent in this sample of patients with WD and was associated with low educational level, number of changes on MRI and MRI hyperintensity in the globus pallidus. PMID:29213476
Mukharji, Projit Bihari
2012-01-01
The "cholera cloud" is one of the most persistent presences in the archives of nineteenth-century cholera in the "British World." Yet it has seldom received anything more than a passing acknowledgment from historians of cholera. Tracing the history of the cholera cloud as an object promises to open up a new dimension of the historically contingent experience of cholera, as well as make a significant contribution to the emergent literature on "thing theory." By conceptualizing the cholera cloud as an object-without-an-essence, this article demonstrates how global cholera pandemics in the nineteenth century produced globalized objects in which a near-universal recognizability and an utterly context-specific set of meanings, visions, and realities could ironically cohabit.
Coupled Low-thrust Trajectory and System Optimization via Multi-Objective Hybrid Optimal Control
NASA Technical Reports Server (NTRS)
Vavrina, Matthew A.; Englander, Jacob Aldo; Ghosh, Alexander R.
2015-01-01
The optimization of low-thrust trajectories is tightly coupled with the spacecraft hardware. Trading trajectory characteristics with system parameters ton identify viable solutions and determine mission sensitivities across discrete hardware configurations is labor intensive. Local independent optimization runs can sample the design space, but a global exploration that resolves the relationships between the system variables across multiple objectives enables a full mapping of the optimal solution space. A multi-objective, hybrid optimal control algorithm is formulated using a multi-objective genetic algorithm as an outer loop systems optimizer around a global trajectory optimizer. The coupled problem is solved simultaneously to generate Pareto-optimal solutions in a single execution. The automated approach is demonstrated on two boulder return missions.
Stein, Michelle B; Slavin-Mulford, Jenelle; Sinclair, S Justin; Siefert, Caleb J; Blais, Mark A
2012-01-01
The Social Cognition and Object Relations Scale-Global rating method (SCORS-G; Stein, Hilsenroth, Slavin-Mulford, & Pinsker, 2011; Westen, 1995) measures the quality of object relations in narrative material. This study employed a multimethod approach to explore the structure and construct validity of the SCORS-G. The Thematic Apperception Test (TAT; Murray, 1943) was administered to 59 patients referred for psychological assessment at a large Northeastern U.S. hospital. The resulting 301 TAT narratives were rated using the SCORS-G method. The 8 SCORS variables were found to have high interrater reliability and good internal consistency. Principal components analysis revealed a 3-component solution with components tapping emotions/affect regulation in relationships, self-image, and aspects of cognition. Next, the construct validity of the SCORS-G components was explored using measures of intellectual and executive functioning, psychopathology, and normal personality. The 3 SCORS-G components showed unique and theoretically meaningful relationships across these broad and diverse psychological measures. This study demonstrates the value of using a standardized scoring method, like the SCORS-G, to reveal the rich and complex nature of narrative material.
NASA Astrophysics Data System (ADS)
Bongiorno, A.; Schulze, A.; Merloni, A.; Zamorani, G.; Ilbert, O.; La Franca, F.; Peng, Y.; Piconcelli, E.; Mainieri, V.; Silverman, J. D.; Brusa, M.; Fiore, F.; Salvato, M.; Scoville, N.
2016-04-01
We investigate the role of supermassive black holes in the global context of galaxy evolution by measuring the host galaxy stellar mass function (HGMF) and the specific accretion rate, that is, λSAR, the distribution function (SARDF), up to z ~ 2.5 with ~1000 X-ray selected AGN from XMM-COSMOS. Using a maximum likelihood approach, we jointly fit the stellar mass function and specific accretion rate distribution function, with the X-ray luminosity function as an additional constraint. Our best-fit model characterizes the SARDF as a double power-law with mass-dependent but redshift-independent break, whose low λSAR slope flattens with increasing redshift while the normalization increases. This implies that for a given stellar mass, higher λSAR objects have a peak in their space density at earlier epoch than the lower λSAR objects, following and mimicking the well-known AGN cosmic downsizing as observed in the AGN luminosity function. The mass function of active galaxies is described by a Schechter function with an almost constant M∗⋆ and a low-mass slope α that flattens with redshift. Compared to the stellar mass function, we find that the HGMF has a similar shape and that up to log (M⋆/M⊙) ~ 11.5, the ratio of AGN host galaxies to star-forming galaxies is basically constant (~10%). Finally, the comparison of the AGN HGMF for different luminosity and specific accretion rate subclasses with a previously published phenomenological model prediction for the "transient" population, which are galaxies in the process of being mass-quenched, reveals that low-luminosity AGN do not appear to be able to contribute significantly to the quenching and that at least at high masses, that is, M⋆ > 1010.7 M⊙, feedback from luminous AGN (log Lbol ≳ 46 [erg/s]) may be responsible for the quenching of star formation in the host galaxy.
2012-01-01
Background Depression in adolescents seems to be a growing problem that causes mental suffering and prevents young people from joining the workforce. There is also a high risk of relapse during adult life. There is emerging evidence for the effect of psychodynamic psychotherapy in adolescents. In-session relational intervention (that is, transference intervention) is a key component of psychodynamic psychotherapy. However, whether depressed adolescents profit most from psychodynamic psychotherapy with or without transference interventions has not been stated. Object The effect of transference interventions in depressed adolescents and the moderator moderating effect of quality of object relations, personality disorder and gender will be explored. Methods and study design The First Experimental Study of Transference Work–In Teenagers (FEST–IT) will be a randomized clinical trial with a dismantling design. The study is aimed to explore the effects of transference work in psychodynamic psychotherapy for adolescents with depression. One hundred patients ages 16 to 18 years old will be randomized to one of two treatment groups, in both of which general psychodynamic techniques will be used. The patients will be treated over 28 weeks with either a moderate level of transference intervention or no transference intervention. Follow-up will be at 1 year after treatment termination. The outcome measures will be the Psychodynamic Functioning Scales (PFS), Inventory of Interpersonal Problems–Circumplex Version (IIP-C), Global Assessment of Functioning (GAF), and the total mean score of Symptom Checklist–90 (Global Severity Index; GSI), Beck Depression Inventory (BDI), and Montgomery Åsberg Rating Scale (MADRS). The quality of adolescents’ relationships will be a central focus of the study, and the Adolescent Relationship Scales (ARS) and Differentiation–Relatedness Scale (DRS) will also be used. Change will be assessed using linear-mixed models. Gender personality disorder (PD) and quality of object relations (QOR) will be the preselected putative moderators. Discussion The object of this clinical trial is to explore the effect of transference interventions in psychodynamic psychotherapy in adolescents with a major depressive disorder. Using a randomized and dismantling design, we hope that the study will add more specific knowledge to the evidence base. Trial registration ClinicalTrials.gov Identifier: NCT01531101 First Experimental Study of Transference work Work–In Teenagers (FEST-IT) PMID:22950546
Das, Swagatam; Biswas, Subhodip; Panigrahi, Bijaya K; Kundu, Souvik; Basu, Debabrota
2014-10-01
This paper presents a novel search metaheuristic inspired from the physical interpretation of the optic flow of information in honeybees about the spatial surroundings that help them orient themselves and navigate through search space while foraging. The interpreted behavior combined with the minimal foraging is simulated by the artificial bee colony algorithm to develop a robust search technique that exhibits elevated performance in multidimensional objective space. Through detailed experimental study and rigorous analysis, we highlight the statistical superiority enjoyed by our algorithm over a wide variety of functions as compared to some highly competitive state-of-the-art methods.
Toward Describing the Effects of Ozone Depletion on Marine Primary Productivity and Carbon Cycling
NASA Technical Reports Server (NTRS)
Cullen, John J.
1995-01-01
This project was aimed at improved predictions of the effects of UVB and ozone depletion on marine primary productivity and carbon flux. A principal objective was to incorporate a new analytical description of photosynthesis as a function of UV and photosynthetically available radiation (Cullen et. al., Science 258:646) into a general oceanographic model. We made significant progress: new insights into the kinetics of photoinhibition were used in the analysis of experiments on Antarctic phytoplankton to generate a general model of UV-induced photoinhibition under the influence of ozone depletion and vertical mixing. The way has been paved for general models on a global scale.
Failure mechanisms of uni-ply composite plates with a circular hole under static compressive loading
NASA Technical Reports Server (NTRS)
Khamseh, A. R.; Waas, A. M.
1992-01-01
The objective of the study was to identify and study the failure mechanisms associated with compressive-loaded uniply graphite/epoxy square plates with a central circular hole. It is found that the type of compressive failure depends on the hole size. For large holes with the diameter/width ratio exceeding 0.062, fiber buckling/kinking initiated at the hole is found to be the dominant failure mechanism. In plates with smaller hole sizes, failure initiates away from the hole edge or complete global failure occurs. Critical buckle wavelengths at failure are presented as a function of the normalized hole diameter.
Psychodynamic psychotherapy for complex trauma: targets, focus, applications, and outcomes
Spermon, Deborah; Darlington, Yvonne; Gibney, Paul
2010-01-01
Complex trauma describes that category of severe, chronic interpersonal trauma usually originating in the formative years of a child. In the adult, this can result in global dissociative difficulties across areas of cognitive, affective, somatic, and behavioral functions. Targeting this field of traumatic pathology, this article reviews the contributions and developments within one broad approach: psychodynamic theory and practice. Brief descriptions of aspects of analytical, Jungian, relational, object relations, and attachment therapeutic approaches are given, along with understandings of pathology and the formulation of therapeutic goals. Major practices within client sessions are canvassed and the issues of researching treatment outcomes are discussed. PMID:22110335
Chakraborty, Arijit; Anstice, Nicola S.; Jacobs, Robert J.; Paudel, Nabin; LaGasse, Linda L.; Lester, Barry M.; McKinlay, Christopher J. D.; Harding, Jane E.; Wouldes, Trecia A.; Thompson, Benjamin
2017-01-01
Global motion perception is often used as an index of dorsal visual stream function in neurodevelopmental studies. However, the relationship between global motion perception and visuomotor control, a primary function of the dorsal stream, is unclear. We measured global motion perception (motion coherence threshold; MCT) and performance on standardized measures of motor function in 606 4.5-year-old children born at risk of abnormal neurodevelopment. Visual acuity, stereoacuity and verbal IQ were also assessed. After adjustment for verbal IQ or both visual acuity and stereoacuity, MCT was modestly, but significantly, associated with all components of motor function with the exception of gross motor scores. In a separate analysis, stereoacuity, but not visual acuity, was significantly associated with both gross and fine motor scores. These results indicate that the development of motion perception and stereoacuity are associated with motor function in pre-school children. PMID:28435122
Fowler, J Christopher; Ackerman, Steven J; Speanburg, Stefanie; Bailey, Adrian; Blagys, Matthew; Conklin, Adam C
2004-12-01
In this study, we examined global treatment outcomes during 16 months of intensive, psychodynamic treatment for 77 inpatients suffering from treatment-refractory disorders. Hypotheses based on the phase model of treatment change (Howard, Lueger, Maling, & Martinovich, 1993; Howard, Moras, Brill, Martinovich, & Lutz, 1996) were supported in the study results. Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) Axis V scales assessing behavioral functioning demonstrated large and medium effect size change, whereas stable, enduring personality functioning assessed by psychoanalytic Rorschach scales and the Social Cognition and Object Relations Scale (Westen, 1995) for the Thematic Apperception Test (Murray, 1943) demonstrated small and medium effect size change. We also report assessment of reliable change index and clinical significance. The ecological validity of Rorschach measures is supported by significant validity coefficients (in the hypothesized directions) between implicit measures of personality functioning and behavioral ratings.
Mataró, Maria; Matarín, Mar; Poca, Maria Antonia; Pueyo, Roser; Sahuquillo, Juan; Barrios, Maite; Junqué, Carme
2007-01-01
Background Normal pressure hydrocephalus (NPH) is associated with corpus callosum abnormalities. Objectives To study the clinical and neuropsychological effect of callosal thinning in 18 patients with idiopathic NPH and to investigate the postsurgical callosal changes in 14 patients. Methods Global corpus callosum size and seven callosal subdivisions were measured. Neuropsychological assessment included an extensive battery assessing memory, psychomotor speed, visuospatial and frontal lobe functioning. Results After surgery, patients showed improvements in memory, visuospatial and frontal lobe functions, and psychomotor speed. Two frontal corpus callosum areas, the genu and the rostral body, were the regions most related to the clinical and neuropsychological dysfunction. After surgery, total corpus callosum and four of the seven subdivisions presented a significant increase in size, which was related to poorer neuropsychological and clinical outcome. Conclusion The postsurgical corpus callosum increase might be the result of decompression, re‐expansion and increase of interstitial fluid, although it may also be caused by differences in shape due to cerebral reorganisation. PMID:17056634
Development of new impact functions for global risk caused by climate change
NASA Astrophysics Data System (ADS)
Miyazaki, C.
2014-12-01
The purpose of our study is to identify and quantify global-scale risks which can be caused by future climate change. In particular, we focus on the global-scale risks which have critical impacts to human environments. Use of impact functions is one of the common way to quantify global-scale risks. Output of impact function is climate impacts (e.g. economic damage by temperature increasing) and input can be global temperature increasing and/or socioeconomic condition (e.g. GDP). As the first step of study, we referred to AR5 WG II report (AR5, hereafter) and comprehensive inventories of climate change risks developed by Strategic R&D Area Project of the Environment Research and Technology Development Fund (ICA-RUS project). Then we extracted information which can be used to develop impact function from them. By following SPM/AR5, we focused on 11 sectors and extracted quantitative description on climate impacts from the AR5 and paper/reports cited in AR5. As a result, we identified about 40 risk items to focus as global-scale risks by climate change. Using the collected information, we tentatively made impact function on sea level rise and so on. In addition, we also extracted the impact functions used in Integrated Assessment Models (IAMs). The literature survey on IAM suggested the risk items considered in IAMs are limited. For instance, although FUND model provides detailed impact functions compared with most of other IAMs, its impact functions deal with only several sectors (e.g. agriculture, forestry, biodiversity, sea level rise, human health, energy demand and water resources). The survey on impact functions in IAMs also suggested impact function for abrupt climate change (so-called Tipping Element) is premature. Moreover, as example for quantifying health risk by our calculation, we also present the result on global-scale projection of the health burden attributable to childhood undernutrition (Ishida et al., 2014, ERL).
Paniagua-Avila, Maria Alejandra; Messenger, Elizabeth; Nelson, Caroline A; Calgua, Erwin; Barg, Frances K; Bream, Kent W; Compher, Charlene; Dean, Anthony J; Martinez-Siekavizza, Sergio; Puac-Polanco, Victor; Richmond, Therese S; Roth, Rudolf R; Branas, Charles C
2017-01-01
Population health outcomes are directly related to robust public health programs, access to basic health services, and a well-trained health-care workforce. Effective health services need to systematically identify solutions, scientifically test these solutions, and share generated knowledge. The World Health Organization (WHO)'s Global Healthcare Workforce Alliance states that the capacity to perform research is an essential factor for well-functioning public health systems. Low- and middle-income countries have greater health-care worker shortages and lower research capacity than higher-income countries. International global health partnerships between higher-income countries and low-middle-income countries aim to directly address such inequalities through capacity building, a process by which human and institutional resources are strengthened and developed, allowing them to perform high-level functions, solve complex problems, and achieve important objectives. The Guatemala-Penn Partners (GPP) is a collaboration among academic centers in Guatemala and the University of Pennsylvania (Penn), in Philadelphia, Pennsylvania that echoes the vision of the WHO's Global Healthcare Workforce Alliance. This article describes the historical development and present organization of the GPP according to its three guiding principles: university-to-university connections, dual autonomies with locally led capacity building, and mutually beneficial exchanges. It describes the GPP activities within the domains of science, health-care education, and public health, emphasizing implementation factors, such as sustainability and scalability, in relation to the guiding principles. Successes and limitations of this innovative model are also analyzed in the hope that the lessons learned may be applied to similar partnerships across the globe.
Paniagua-Avila, Maria Alejandra; Messenger, Elizabeth; Nelson, Caroline A.; Calgua, Erwin; Barg, Frances K.; Bream, Kent W.; Compher, Charlene; Dean, Anthony J.; Martinez-Siekavizza, Sergio; Puac-Polanco, Victor; Richmond, Therese S.; Roth, Rudolf R.; Branas, Charles C.
2017-01-01
Population health outcomes are directly related to robust public health programs, access to basic health services, and a well-trained health-care workforce. Effective health services need to systematically identify solutions, scientifically test these solutions, and share generated knowledge. The World Health Organization (WHO)’s Global Healthcare Workforce Alliance states that the capacity to perform research is an essential factor for well-functioning public health systems. Low- and middle-income countries have greater health-care worker shortages and lower research capacity than higher-income countries. International global health partnerships between higher-income countries and low-middle-income countries aim to directly address such inequalities through capacity building, a process by which human and institutional resources are strengthened and developed, allowing them to perform high-level functions, solve complex problems, and achieve important objectives. The Guatemala–Penn Partners (GPP) is a collaboration among academic centers in Guatemala and the University of Pennsylvania (Penn), in Philadelphia, Pennsylvania that echoes the vision of the WHO’s Global Healthcare Workforce Alliance. This article describes the historical development and present organization of the GPP according to its three guiding principles: university-to-university connections, dual autonomies with locally led capacity building, and mutually beneficial exchanges. It describes the GPP activities within the domains of science, health-care education, and public health, emphasizing implementation factors, such as sustainability and scalability, in relation to the guiding principles. Successes and limitations of this innovative model are also analyzed in the hope that the lessons learned may be applied to similar partnerships across the globe. PMID:28443274
Okatch, Harriet; Sowicz, Timothy Joseph; Teng, Helen; Ramogola-Masire, Doreen; Buttenheim, Alison M
2018-05-01
To design and implement a case study on the cervical cancer screening program in Botswana to teach public and global health competencies to undergraduate nursing students. The case study was developed following a review of the literature on the epidemiology and health policies of cervical cancer in Botswana, and an interview with an obstetrician/gynecologist engaged in both clinical practice and research in Botswana. The case study has been implemented over seven semesters to students enrolled in the Nursing in the Community course at the University of Pennsylvania. Approximately 75-100 students are enrolled each semester. Student's perceptions of epidemiologic skills gained and group functioning. Students responded to an open-ended question about lessons learned and offered suggestions to improve the learning experience. Faculty assessment of student deliverables demonstrated that students achieved the learning objectives and mastered necessary competencies. More than 70% (n = 69) of the students indicated that they acquired relevant skills at greater than a satisfactory level. Generally, students had great experiences working in groups measured across five dimensions: engagement/contribution, creativity/resilience, on task/works independently, social interaction/communication, and preparedness. However, isolated cases of poor group functioning were reported for engagement/contribution, and creativity/resilience. The case study, which has been revised with respect to length, content and group processes, has been valuable in educating undergraduate nursing students in a more engaging way that mimics real life public health nursing scenarios. Students achieved both public and global health competencies through participation in the case study. © 2018 Wiley Periodicals, Inc.
An Investigation of Emotion Recognition and Theory of Mind in People with Chronic Heart Failure
Habota, Tina; McLennan, Skye N.; Cameron, Jan; Ski, Chantal F.; Thompson, David R.; Rendell, Peter G.
2015-01-01
Objectives Cognitive deficits are common in patients with chronic heart failure (CHF), but no study has investigated whether these deficits extend to social cognition. The present study provided the first empirical assessment of emotion recognition and theory of mind (ToM) in patients with CHF. In addition, it assessed whether each of these social cognitive constructs was associated with more general cognitive impairment. Methods A group comparison design was used, with 31 CHF patients compared to 38 demographically matched controls. The Ekman Faces test was used to assess emotion recognition, and the Mind in the Eyes test to measure ToM. Measures assessing global cognition, executive functions, and verbal memory were also administered. Results There were no differences between groups on emotion recognition or ToM. The CHF group’s performance was poorer on some executive measures, but memory was relatively preserved. In the CHF group, both emotion recognition performance and ToM ability correlated moderately with global cognition (r = .38, p = .034; r = .49, p = .005, respectively), but not with executive function or verbal memory. Conclusion CHF patients with lower cognitive ability were more likely to have difficulty recognizing emotions and inferring the mental states of others. Clinical implications of these findings are discussed. PMID:26529409
Reading laterally: the cerebral hemispheric use of spatial frequencies in visual word recognition.
Tadros, Karine; Dupuis-Roy, Nicolas; Fiset, Daniel; Arguin, Martin; Gosselin, Frédéric
2013-01-04
It is generally accepted that the left hemisphere (LH) is more capable for reading than the right hemisphere (RH). Left hemifield presentations (initially processed by the RH) lead to a globally higher error rate, slower word identification, and a significantly stronger word length effect (i.e., slower reaction times for longer words). Because the visuo-perceptual mechanisms of the brain for word recognition are primarily localized in the LH (Cohen et al., 2003), it is possible that this part of the brain possesses better spatial frequency (SF) tuning for processing the visual properties of words than the RH. The main objective of this study is to determine the SF tuning functions of the LH and RH for word recognition. Each word image was randomly sampled in the SF domain using the SF bubbles method (Willenbockel et al., 2010) and was presented laterally to the left or right visual hemifield. As expected, the LH requires less visual information than the RH to reach the same level of performance, illustrating the well-known LH advantage for word recognition. Globally, the SF tuning of both hemispheres is similar. However, these seemingly identical tuning functions hide important differences. Most importantly, we argue that the RH requires higher SFs to identify longer words because of crowding.
Level set method for image segmentation based on moment competition
NASA Astrophysics Data System (ADS)
Min, Hai; Wang, Xiao-Feng; Huang, De-Shuang; Jin, Jing; Wang, Hong-Zhi; Li, Hai
2015-05-01
We propose a level set method for image segmentation which introduces the moment competition and weakly supervised information into the energy functional construction. Different from the region-based level set methods which use force competition, the moment competition is adopted to drive the contour evolution. Here, a so-called three-point labeling scheme is proposed to manually label three independent points (weakly supervised information) on the image. Then the intensity differences between the three points and the unlabeled pixels are used to construct the force arms for each image pixel. The corresponding force is generated from the global statistical information of a region-based method and weighted by the force arm. As a result, the moment can be constructed and incorporated into the energy functional to drive the evolving contour to approach the object boundary. In our method, the force arm can take full advantage of the three-point labeling scheme to constrain the moment competition. Additionally, the global statistical information and weakly supervised information are successfully integrated, which makes the proposed method more robust than traditional methods for initial contour placement and parameter setting. Experimental results with performance analysis also show the superiority of the proposed method on segmenting different types of complicated images, such as noisy images, three-phase images, images with intensity inhomogeneity, and texture images.
An Active Contour Model Based on Adaptive Threshold for Extraction of Cerebral Vascular Structures.
Wang, Jiaxin; Zhao, Shifeng; Liu, Zifeng; Tian, Yun; Duan, Fuqing; Pan, Yutong
2016-01-01
Cerebral vessel segmentation is essential and helpful for the clinical diagnosis and the related research. However, automatic segmentation of brain vessels remains challenging because of the variable vessel shape and high complex of vessel geometry. This study proposes a new active contour model (ACM) implemented by the level-set method for segmenting vessels from TOF-MRA data. The energy function of the new model, combining both region intensity and boundary information, is composed of two region terms, one boundary term and one penalty term. The global threshold representing the lower gray boundary of the target object by maximum intensity projection (MIP) is defined in the first-region term, and it is used to guide the segmentation of the thick vessels. In the second term, a dynamic intensity threshold is employed to extract the tiny vessels. The boundary term is used to drive the contours to evolve towards the boundaries with high gradients. The penalty term is used to avoid reinitialization of the level-set function. Experimental results on 10 clinical brain data sets demonstrate that our method is not only able to achieve better Dice Similarity Coefficient than the global threshold based method and localized hybrid level-set method but also able to extract whole cerebral vessel trees, including the thin vessels.
Cecchi, Francesca; Del Canto, Antonio; Paperini, Anita; Boni, Roberta; Pasquini, Guido; Vannetti, Federica; Macchi, Claudio
2015-01-01
Objective. Comparing global postural reeducation (GPR) to a standard physiotherapy treatment (PT) based on active exercises, stretching, and massaging for improving pain and function in chronic low back pain (CLBP) patients. Design. Prospective controlled study. Setting. Outpatient rehabilitation facility. Participants. Adult patients with diagnosis of nonspecific, chronic (>6 months) low back pain. Interventions. Both treatments consisted of 15 sessions of one hour each, twice a week including patient education. Measures. Roland Morris Disability Questionnaire to evaluate disability, and Numeric Analog Scale for pain. A score change >30% was considered clinically significant. Past treatments, use of medications, smoking habits, height, weight, profession, and physical activity were also recorded on baseline, on discharge, and 1 year after discharge (resp., T0, T1, and T2). Results. At T0 103 patients with cLBP (51 cases and 52 controls) were recruited. The treatment (T1) has been completed by 79 (T1) of which 60 then carried out the 1-year follow-up (T2). Both GPR and PT at T1 were associated with a significant statistical and clinical improvement in pain and function, compared to T0. At T2, only pain in GPR still registered a statistically significant improvement. PMID:25945360
Barton, David J.; Kumar, Raj G.; McCullough, Emily H.; Galang, Gary; Arenth, Patricia M.; Berga, Sarah L.; Wagner, Amy K.
2015-01-01
Objective (1) Examine relationships between persistent hypogonadotropic hypogonadism (PHH) and long-term outcomes after severe traumatic brain injury (TBI); (2) determine if sub-acute testosterone levels can predict PHH. Setting Level 1 trauma center at a university hospital. Participants Consecutive sample of men with severe TBI between 2004 and 2009. Design Prospective cohort study. Main Measures Post-TBI blood samples were collected during week 1, every 2 weeks until 26 weeks, and at 52 weeks. Serum hormone levels were measured, and individuals were designated as having PHH if ≥50% of samples met criteria for hypogonadotropic hypogonadism. At 6 and 12 months post-injury, we assessed global outcome, disability, functional cognition, depression, and quality-of-life. Results We recruited 78 men; median (IQR) age was 28.5 (22–42) years. 34 patients (44%) had PHH during the first year post-injury. Multivariable regression, controlling for age, demonstrated PHH status predicted worse global outcome scores, more disability, and reduced functional cognition at 6 and 12 months post-TBI. Two-step testosterone screening for PHH at 12–16 weeks post-injury yielded a sensitivity of 79% and specificity of 100%. Conclusion PHH status in men predicts poor outcome after severe TBI, and PHH can accurately be predicted at 12–16 weeks. PMID:26360007
Knierim, James J; Neunuebel, Joshua P; Deshmukh, Sachin S
2014-02-05
The hippocampus receives its major cortical input from the medial entorhinal cortex (MEC) and the lateral entorhinal cortex (LEC). It is commonly believed that the MEC provides spatial input to the hippocampus, whereas the LEC provides non-spatial input. We review new data which suggest that this simple dichotomy between 'where' versus 'what' needs revision. We propose a refinement of this model, which is more complex than the simple spatial-non-spatial dichotomy. MEC is proposed to be involved in path integration computations based on a global frame of reference, primarily using internally generated, self-motion cues and external input about environmental boundaries and scenes; it provides the hippocampus with a coordinate system that underlies the spatial context of an experience. LEC is proposed to process information about individual items and locations based on a local frame of reference, primarily using external sensory input; it provides the hippocampus with information about the content of an experience.
Application of the EM algorithm to radiographic images.
Brailean, J C; Little, D; Giger, M L; Chen, C T; Sullivan, B J
1992-01-01
The expectation maximization (EM) algorithm has received considerable attention in the area of positron emitted tomography (PET) as a restoration and reconstruction technique. In this paper, the restoration capabilities of the EM algorithm when applied to radiographic images is investigated. This application does not involve reconstruction. The performance of the EM algorithm is quantitatively evaluated using a "perceived" signal-to-noise ratio (SNR) as the image quality metric. This perceived SNR is based on statistical decision theory and includes both the observer's visual response function and a noise component internal to the eye-brain system. For a variety of processing parameters, the relative SNR (ratio of the processed SNR to the original SNR) is calculated and used as a metric to compare quantitatively the effects of the EM algorithm with two other image enhancement techniques: global contrast enhancement (windowing) and unsharp mask filtering. The results suggest that the EM algorithm's performance is superior when compared to unsharp mask filtering and global contrast enhancement for radiographic images which contain objects smaller than 4 mm.
Application of genetic algorithms to focal mechanism determination
NASA Astrophysics Data System (ADS)
Kobayashi, Reiji; Nakanishi, Ichiro
1994-04-01
Genetic algorithms are a new class of methods for global optimization. They resemble Monte Carlo techniques, but search for solutions more efficiently than uniform Monte Carlo sampling. In the field of geophysics, genetic algorithms have recently been used to solve some non-linear inverse problems (e.g., earthquake location, waveform inversion, migration velocity estimation). We present an application of genetic algorithms to focal mechanism determination from first-motion polarities of P-waves and apply our method to two recent large events, the Kushiro-oki earthquake of January 15, 1993 and the SW Hokkaido (Japan Sea) earthquake of July 12, 1993. Initial solution and curvature information of the objective function that gradient methods need are not required in our approach. Moreover globally optimal solutions can be efficiently obtained. Calculation of polarities based on double-couple models is the most time-consuming part of the source mechanism determination. The amount of calculations required by the method designed in this study is much less than that of previous grid search methods.
Knierim, James J.; Neunuebel, Joshua P.; Deshmukh, Sachin S.
2014-01-01
The hippocampus receives its major cortical input from the medial entorhinal cortex (MEC) and the lateral entorhinal cortex (LEC). It is commonly believed that the MEC provides spatial input to the hippocampus, whereas the LEC provides non-spatial input. We review new data which suggest that this simple dichotomy between ‘where’ versus ‘what’ needs revision. We propose a refinement of this model, which is more complex than the simple spatial–non-spatial dichotomy. MEC is proposed to be involved in path integration computations based on a global frame of reference, primarily using internally generated, self-motion cues and external input about environmental boundaries and scenes; it provides the hippocampus with a coordinate system that underlies the spatial context of an experience. LEC is proposed to process information about individual items and locations based on a local frame of reference, primarily using external sensory input; it provides the hippocampus with information about the content of an experience. PMID:24366146
The Impact of Globalization on Teaching Profession: The Global Teacher
ERIC Educational Resources Information Center
Canli, Suzan; Demirtas, Hasan
2018-01-01
The main objective of the present study was to examine the impact of globalization on the teaching profession based on teacher views. Furthermore, the study aimed to make recommendations for the practitioners and the researchers based on the study findings. In the study, the qualitative phenomenology research method was used and the participants…
Species pool, human population, and global versus regional invasion patterns
Qinfeng Guo; Basil V. Iannone III; Gabriela C. Nunez-Mir; Kevin M. Potter; Christopher M. Oswalt; Songlin Fei
2017-01-01
Context Biological invasions are among the greatest global and regional threats to biomes in the Anthropocene. Islands, in particular, have been perceived to have higher vulnerability to invasions. Because of the dynamic nature of ongoing invasions, distinguishing regional patterns from global patterns and their underlying determinants remains a challenge. Objectives...
ERIC Educational Resources Information Center
Stahelin, Nicolas
2017-01-01
This research is a qualitative case study of global and national (Brazilian) Environmental and Sustainability Education (ESE) policies in historical perspectives. My overall objectives are two-fold: First, to understand how global ESE policy frameworks have evolved ideologically over time--a concept I refer to as ESE policy trajectories; and…
College of Business Majors' Perceptions toward Globalization: An Empirical Study
ERIC Educational Resources Information Center
Janavaras, Basil; Kuzma, John; Thiewes, Harold
2008-01-01
The objective of this paper is to determine the extent to which business majors' attitudes towards globalization are influenced by the area of selected study. Research has documented that more favorable attitudes towards globalization are found among college students, and specifically, these more favorable attitudes are found in business majors.…
Trends in management of the world's forests and impacts on carbon stocks
Richard Birdsey; Yude Pan
2015-01-01
Global forests are increasingly affected by land-use change, fragmentation, changing management objectives, and degradation. In this paper we broadly characterize trends in global forest area by intensity of management, and provide an overview of changes in global carbon stocks associated with managed forests. We discuss different interpretations of "management...
A Proposed Framework for Global Leadership Education: Learning Objectives and Curricula
ERIC Educational Resources Information Center
Brown, LeAnn M.; Whitaker, Brett L.; Brungardt, Curtis L.
2012-01-01
Many traditional leadership education paradigms are challenged by the transformational nature of globalization and are limited in application in diverse and complex contexts. In order to address these issues, a new framework must be adopted within higher education leadership programs to educate the next generation of global leaders. This paper…
The Foreseeable Harms of Trump's Global Gag Rule.
Bingenheimer, Jeffrey B; Skuster, Patty
2017-09-01
As one of his first acts as President of the United States, Donald Trump signed an executive order reinstating a version of the global gag rule. Under this rule, US grantees are barred from receiving global health funding if they engage in abortion-related work: not only abortion services, but also abortion referrals and counseling or advocacy for the liberalization of abortion laws. Critics of the Trump global gag rule generally raise three classes of objections: (1) that the rule fails to accomplish its presumed objective of reducing the number of abortions; (2) that it negatively affects the health and well-being of individuals and populations in affected countries; and (3) that it interferes with governments' ability to meet their international obligations. In this commentary, we examine the scientific and policy bases for these criticisms. © 2017 The Population Council, Inc.
Ten-Year Course of Borderline Personality Disorder
Gunderson, John G.; Stout, Robert L.; McGlashan, Thomas H.; Shea, M. Tracie; Morey, Leslie C.; Grilo, Carlos M.; Zanarini, Mary C.; Yen, Shirley; Markowitz, John C.; Sanislow, Charles; Ansell, Emily; Pinto, Anthony; Skodol, Andrew E.
2011-01-01
Context Borderline personality disorder (BPD) is traditionally considered chronic and intractable. Objective To compare the course of BPD’s psychopathology and social function with that of other personality disorders and with major depressive disorder (MDD) over 10 years. Design A collaborative study of treatment-seeking, 18-to 45-year-old patients followed up with standardized, reliable, and repeated measures of diagnostic remission and relapse and of both global social functioning and subtypes of social functioning. Setting Nineteen clinical settings (hospital and outpatient) in 4 northeastern US cities. Participants Three study groups, including 175 patients with BPD, 312 with cluster C personality disorders, and 95 with MDD but no personality disorder. Main Outcome Measures The Diagnostic Interview for DSM-IV Personality Disorders and its follow-along version (the Diagnostic Interview for DSM-IV Personality Disorders–Follow-Along Version) were used to diagnose personality disorders and assess changes in them. The Structured Clinical Interview for DSM-IV Axis I Disorders and the Longitudinal Interval Follow-up Evaluation were used to diagnose MDD and assess changes in MDD and in social function. Results Eighty-five percent of patients with BPD remitted. Remission of BPD was slower than for MDD (P<.001) and minimally slower than for other personality disorders (P<.03). Twelve percent of patients with BPD relapsed, a rate less frequent and slower than for patients with MDD (P<.001) and other personality disorders (P=.008). All BPD criteria declined at similar rates. Social function scores showed severe impairment with only modest albeit statistically significant improvement; patients with BPD remained persistently more dysfunctional than the other 2 groups (P<.001). Reductions in criteria predicted subsequent improvements in DSM-IV Axis V Global Assessment of Functioning scores (P<.001). Conclusions The 10-year course of BPD is characterized by high rates of remission, low rates of relapse, and severe and persistent impairment in social functioning. These results inform expectations of patients, families, and clinicians and document the severe public health burden of this disorder. PMID:21464343
Biological soil crusts: Diminutive communities of potential global importance
Ferrenberg, Scott; Tucker, Colin; Reed, Sasha C.
2017-01-01
Biological soil crusts (biocrusts) are widespread, diverse communities of cyanobacteria, fungi, lichens, and mosses living on soil surfaces, primarily in drylands. Biocrusts can locally govern primary production, soil fertility, hydrology, and surface energy balance, with considerable variation in these functions across alternate community states. Further, these communities have been implicated in Earth system functioning via potential influences on global biogeochemistry and climate. Biocrusts are easily destroyed by disturbances and appear to be exceptionally vulnerable to warming temperatures and altered precipitation inputs, signaling possible losses of dryland functions with global change. Despite these concerns, we lack sufficient spatiotemporal data on biocrust function, cover, and community structure to confidently assess their ecological roles across the extensive dryland biome. Here, we present the case for cross-scale research and restoration efforts coupled with remote-sensing and modeling approaches that improve our collective understanding of biocrust responses to global change and the ecological roles of these diminutive communities at global scales.
Mapping the functional connectome in traumatic brain injury: What can graph metrics tell us?
Caeyenberghs, Karen; Verhelst, Helena; Clemente, Adam; Wilson, Peter H
2017-10-15
Traumatic brain injury (TBI) is associated with cognitive and motor deficits, and poses a significant personal, societal, and economic burden. One mechanism by which TBI is thought to affect cognition and behavior is through changes in functional connectivity. Graph theory is a powerful framework for quantifying topological features of neuroimaging-derived functional networks. The objective of this paper is to review studies examining functional connectivity in TBI with an emphasis on graph theoretical analysis that is proving to be valuable in uncovering network abnormalities in this condition. We review studies that have examined TBI-related alterations in different properties of the functional brain network, including global integration, segregation, centrality and resilience. We focus on functional data using task-related fMRI or resting-state fMRI in patients with TBI of different severity and recovery phase, and consider how graph metrics may inform rehabilitation and enhance efficacy. Moreover, we outline some methodological challenges associated with the examination of functional connectivity in patients with brain injury, including the sample size, parcellation scheme used, node definition and subgroup analyses. The findings suggest that TBI is associated with hyperconnectivity and a suboptimal global integration, characterized by increased connectivity degree and strength and reduced efficiency of functional networks. This altered functional connectivity, also evident in other clinical populations, is attributable to diffuse white matter pathology and reductions in gray and white matter volume. These functional alterations are implicated in post-concussional symptoms, posttraumatic stress and neurocognitive dysfunction after TBI. Finally, the effects of focal lesions have been found to depend critically on topological position and their role in the network. Graph theory is a unique and powerful tool for exploring functional connectivity in brain-injured patients. One limitation is that its results do not provide specific measures about the biophysical mechanism underlying TBI. Continued work in this field will hopefully see graph metrics used as biomarkers to provide more accurate diagnosis and help guide treatment at the individual patient level. Copyright © 2016. Published by Elsevier Inc.
Turgay, Atilla; Ginsberg, Lawrence; Sarkis, Elias; Jain, Rakesh; Adeyi, Ben; Gao, Joseph; Dirks, Bryan; Babcock, Thomas; Scheckner, Brian; Richards, Cynthia; Lasser, Robert
2010-01-01
Abstract Objective To assess the effects of lisdexamfetamine dimesylate (LDX) on executive function (EF) behaviors in children with attention-deficit/hyperactivity disorder (ADHD). Methods This observational, open-label, 7-week, dose-optimization study of LDX (20–70 mg/day) in children with ADHD evaluated efficacy with the ADHD Rating Scale IV; safety measures included adverse events (AEs). EF was assessed with the Behavior Rating Inventory of Executive Function (BRIEF). Post hoc analyses examined BRIEF scores by sex, ADHD subtype, comorbid psychiatric symptoms, and common treatment-emergent AEs (TEAEs). ADHD Rating Scale IV scores were assessed in subjects categorized by baseline BRIEF global executive composite T scores with clinically significant (≥65) or not clinically significant (<65) impairment in EF. Results Mean (standard deviation) change from baseline to endpoint for BRIEF of −17.9 (12.5) for Global Executive Composite, −15.4 (12.6) for Behavioral Regulation Index, and −17.6 (12.3) for Metacognition Index demonstrated improvement with LDX (pooled doses; p < 0.0001 for all). Improvements in BRIEF scores were seen regardless of sex, ADHD subtype, comorbid psychiatric symptoms, common TEAEs, or baseline EF impairment category. TEAEs included decreased appetite, decreased weight, irritability, insomnia, headache, upper abdominal pain, and initial insomnia. Conclusions Improvements were demonstrated in EF behaviors and ADHD symptoms with LDX. LDX safety profile was consistent with long-acting stimulant use. PMID:21186969
NASA Astrophysics Data System (ADS)
Buyuk, Ersin; Karaman, Abdullah
2017-04-01
We estimated transmissivity and storage coefficient values from the single well water-level measurements positioned ahead of the mining face by using particle swarm optimization (PSO) technique. The water-level response to the advancing mining face contains an semi-analytical function that is not suitable for conventional inversion shemes because the partial derivative is difficult to calculate . Morever, the logaritmic behaviour of the model create difficulty for obtaining an initial model that may lead to a stable convergence. The PSO appears to obtain a reliable solution that produce a reasonable fit between water-level data and model function response. Optimization methods have been used to find optimum conditions consisting either minimum or maximum of a given objective function with regard to some criteria. Unlike PSO, traditional non-linear optimization methods have been used for many hydrogeologic and geophysical engineering problems. These methods indicate some difficulties such as dependencies to initial model, evolution of the partial derivatives that is required while linearizing the model and trapping at local optimum. Recently, Particle swarm optimization (PSO) became the focus of modern global optimization method that is inspired from the social behaviour of birds of swarms, and appears to be a reliable and powerful algorithms for complex engineering applications. PSO that is not dependent on an initial model, and non-derivative stochastic process appears to be capable of searching all possible solutions in the model space either around local or global optimum points.
Jiao, Bingqing; Zhang, Delong; Liang, Aiying; Liang, Bishan; Wang, Zengjian; Li, Junchao; Cai, Yuxuan; Gao, Mengxia; Gao, Zhenni; Chang, Song; Huang, Ruiwang; Liu, Ming
2017-10-01
Previous studies have indicated a tight linkage between resting-state functional connectivity of the human brain and creative ability. This study aimed to further investigate the association between the topological organization of resting-state brain networks and creativity. Therefore, we acquired resting-state fMRI data from 22 high-creativity participants and 22 low-creativity participants (as determined by their Torrance Tests of Creative Thinking scores). We then constructed functional brain networks for each participant and assessed group differences in network topological properties before exploring the relationships between respective network topological properties and creative ability. We identified an optimized organization of intrinsic brain networks in both groups. However, compared with low-creativity participants, high-creativity participants exhibited increased global efficiency and substantially decreased path length, suggesting increased efficiency of information transmission across brain networks in creative individuals. Using a multiple linear regression model, we further demonstrated that regional functional integration properties (i.e., the betweenness centrality and global efficiency) of brain networks, particularly the default mode network (DMN) and sensorimotor network (SMN), significantly predicted the individual differences in creative ability. Furthermore, the associations between network regional properties and creative performance were creativity-level dependent, where the difference in the resource control component may be important in explaining individual difference in creative performance. These findings provide novel insights into the neural substrate of creativity and may facilitate objective identification of creative ability. Copyright © 2017 Elsevier B.V. All rights reserved.
West, Amy E; Weinstein, Sally M; Peters, Amy T; Katz, Andrea C; Henry, David B; Cruz, Rick A; Pavuluri, Mani N
2014-11-01
Previous studies have found that family-based psychosocial treatments are effective adjuncts to pharmacotherapy among adults and adolescents with bipolar disorder (BD). The objective of this study was to compare the efficacy of adjunctive child- and family-focused cognitive-behavioral therapy (CFF-CBT) to psychotherapy as usual (control) for mood symptom severity and global functioning in children with BD. Sixty-nine youth, aged 7 to 13 years (mean = 9.19, SD = 1.61) with DSM-IV-TR bipolar I, II, or not otherwise specified (NOS) disorder were randomly assigned to CFF-CBT or control groups. Both treatments consisted of 12 weekly sessions followed by 6 monthly booster sessions delivered over a total of 9 months. Independent evaluators assessed participants at baseline, week 4, week 8, week 12 (posttreatment), and week 39 (6-month follow-up). Participants in CFF-CBT attended more sessions, were less likely to drop out, and reported greater satisfaction with treatment than controls. CFF-CBT demonstrated efficacy compared to the control treatment in reducing parent-reported mania at posttreatment and depression symptoms at posttreatment and follow-up. Global functioning did not differ at posttreatment but was higher among CFF-CBT participants at follow-up. CFF-CBT may be efficacious in reducing acute mood symptoms and improving long-term psychosocial functioning among children with BD. Copyright © 2014 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Case studies in key selected coral reefs and watersheds will be completed to provide scientific data, concepts and models that describe the responses of the functioning of these ecosystems to global change stressors. The studies will focus on relating global changes to local and...
The holographic dual of the Penrose transform
NASA Astrophysics Data System (ADS)
Neiman, Yasha
2018-01-01
We consider the holographic duality between type-A higher-spin gravity in AdS4 and the free U( N) vector model. In the bulk, linearized solutions can be translated into twistor functions via the Penrose transform. We propose a holographic dual to this transform, which translates between twistor functions and CFT sources and operators. We present a twistorial expression for the partition function, which makes global higher-spin symmetry manifest, and appears to automatically include all necessary contact terms. In this picture, twistor space provides a fully nonlocal, gauge-invariant description underlying both bulk and boundary spacetime pictures. While the bulk theory is handled at the linear level, our formula for the partition function includes the effects of bulk interactions. Thus, the CFT is used to solve the bulk, with twistors as a language common to both. A key ingredient in our result is the study of ordinary spacetime symmetries within the fundamental representation of higher-spin algebra. The object that makes these "square root" spacetime symmetries manifest becomes the kernel of our boundary/twistor transform, while the original Penrose transform is identified as a "square root" of CPT.
A Lagrange multiplier and Hopfield-type barrier function method for the traveling salesman problem.
Dang, Chuangyin; Xu, Lei
2002-02-01
A Lagrange multiplier and Hopfield-type barrier function method is proposed for approximating a solution of the traveling salesman problem. The method is derived from applications of Lagrange multipliers and a Hopfield-type barrier function and attempts to produce a solution of high quality by generating a minimum point of a barrier problem for a sequence of descending values of the barrier parameter. For any given value of the barrier parameter, the method searches for a minimum point of the barrier problem in a feasible descent direction, which has a desired property that lower and upper bounds on variables are always satisfied automatically if the step length is a number between zero and one. At each iteration, the feasible descent direction is found by updating Lagrange multipliers with a globally convergent iterative procedure. For any given value of the barrier parameter, the method converges to a stationary point of the barrier problem without any condition on the objective function. Theoretical and numerical results show that the method seems more effective and efficient than the softassign algorithm.
Conformational space annealing scheme in the inverse design of functional materials
NASA Astrophysics Data System (ADS)
Kim, Sunghyun; Lee, In-Ho; Lee, Jooyoung; Oh, Young Jun; Chang, Kee Joo
2015-03-01
Recently, the so-called inverse method has drawn much attention, in which specific electronic properties are initially assigned and target materials are subsequently searched. In this work, we develop a new scheme for the inverse design of functional materials, in which the conformational space annealing (CSA) algorithm for global optimization is combined with first-principles density functional calculations. To implement the CSA, we need a series of ingredients, (i) an objective function to minimize, (ii) a 'distance' measure between two conformations, (iii) a local enthalpy minimizer of a given conformation, (iv) ways to combine two parent conformations to generate a daughter one, (v) a special conformation update scheme, and (vi) an annealing method in the 'distance' parameter axis. We show the results of applications for searching for Si crystals with direct band gaps and the lowest-enthalpy phase of boron at a finite pressure and discuss the efficiency of the present scheme. This work is supported by the National Research Foundation of Korea (NRF) under Grant No. NRF-2005-0093845 and by Samsung Science and Technology Foundation under Grant No. SSTFBA1401-08.
Global Warming Estimation from MSU
NASA Technical Reports Server (NTRS)
Prabhakara, C.; Iacovazzi, Robert, Jr.
1999-01-01
In this study, we have developed time series of global temperature from 1980-97 based on the Microwave Sounding Unit (MSU) Ch 2 (53.74 GHz) observations taken from polar-orbiting NOAA operational satellites. In order to create these time series, systematic errors (approx. 0.1 K) in the Ch 2 data arising from inter-satellite differences are removed objectively. On the other hand, smaller systematic errors (approx. 0.03 K) in the data due to orbital drift of each satellite cannot be removed objectively. Such errors are expected to remain in the time series and leave an uncertainty in the inferred global temperature trend. With the help of a statistical method, the error in the MSU inferred global temperature trend resulting from orbital drifts and residual inter-satellite differences of all satellites is estimated to be 0.06 K decade. Incorporating this error, our analysis shows that the global temperature increased at a rate of 0.13 +/- 0.06 K decade during 1980-97.
Space Shuttle to deploy Magellan planetary science mission
NASA Technical Reports Server (NTRS)
1989-01-01
The objectives of Space Shuttle Mission STS-30 are described along with major flight activities, prelaunch and launch operations, trajectory sequence of events, and landing and post-landing operations. The primary objective of STS-30 is to successfully deploy the Magellan spacecraft into low earth orbit. Following deployment, Magellan will be propelled to its Venus trajectory by an Inertial Upper Stage booster. The objectives of the Magellan mission are to obtain radar images of more than 70 percent of Venus' surface, a near-global topographic map, and near-global gravity field data. Secondary STS-30 payloads include the Fluids Experiment Apparatus (FEA) and the Mesoscale Lightning Experiment (MLE).
Location of geographical objects in crisis situations
NASA Astrophysics Data System (ADS)
Rybansky, M.; Kratochvil, V.
2014-02-01
This article summarizes the various expressions of object positioning using different coordinate data and different methods, such as use of maps, exploiting the properties of digital Global System for Mobile Communications (GSM) networks, Global Navigational Satellite Systems (GNSS), Inertial Navigation Systems (INS), Inertial Measurement Systems (IMS), hybrid methods and non-contact (remote sensing) methods; all with varying level of accuracy. Furthermore, the article describes some geographical identifiers and verbal means to describe location of geographical objects such as settlements, rivers, forest, roads, etc. All of the location methods have some advantages and disadvantages, especially in emergency situations, when usually the crisis management has a lack of time in a decision process.
Assessing the Agricultural Vulnerability for India under Changing Climate
NASA Astrophysics Data System (ADS)
Sharma, Tarul; Vardhan Murari, Harsha; Karmakar, Subhankar; Ghosh, Subimal; Singh, Jitendra
2016-04-01
Global climate change has proven to show majorly negative impacts for the far future. These negative impacts adversely affect almost all the fields including agriculture, water resources, tourism, and marine ecosystem. Among these, the effects on agriculture are considered to be of prime importance since its regional impacts can directly affect the global food security. Under such lines, it becomes essential to understand how climate change directs agricultural production for a region along with its vulnerability. In India, rice and wheat are considered as major staple diet and hence understanding its production loss/gain due to regional vulnerability to climate change becomes necessary. Here, an attempt has been made to understand the agricultural vulnerability for rice and wheat, considering yield as a function of temperature and precipitation during growing period. In order to accomplish this objective, the ratio of actual to potential evapo-transpiration has been considered which serves as a reliable indicator; with more this ratio towards unity, less vulnerable will be the region. The current objective needs an integration of climatic, hydrological and agricultural parameters; that can be achieved by simulating a climate data driven hydrologic (Variable Infiltration Capacity, VIC) model and a crop (Decision Support System for Agrotechnology Transfer, DSSAT) model. The proposed framework is an attempt to derive a crop vulnerability map that can facilitate in strategizing adaption practices which can reduce the adverse impacts of climate change in future.
Life Cycle Assessment and Carbon Footprint in the Wine Supply-Chain
NASA Astrophysics Data System (ADS)
Pattara, Claudio; Raggi, Andrea; Cichelli, Angelo
2012-06-01
Global warming represents one of the most critical internationally perceived environmental issues. The growing, and increasingly global, wine sector is one of the industries which is under increasing pressure to adopt approaches for environmental assessment and reporting of product-related greenhouse gas emissions. The International Organization for Vine and Wine has recently recognized the need to develop a standard and objective methodology and a related tool for calculating carbon footprint (CF). This study applied this tool to a wine previously analyzed using the life cycle assessment (LCA) methodology. The objective was to test the tool as regards both its potential and possible limitations, and thus to assess its suitability as a standard tool. Despite the tool's user-friendliness, a number of limitations were noted including the lack of accurate baseline data, a partial system boundary and the impossibility of dealing with the multi-functionality issue. When the CF and LCA results are compared in absolute terms, large discrepancies become obvious due to a number of different assumptions, as well as the modeling framework adopted. Nonetheless, in relative terms the results seem to be quite consistent. However, a critical limitation of the CF methodology was its focus on a single issue, which can lead to burden shifting. In conclusion, the study confirmed the need for both further improvement and adaptation to additional contexts and further studies to validate the use of this tool in different companies.
Life cycle assessment and carbon footprint in the wine supply-chain.
Pattara, Claudio; Raggi, Andrea; Cichelli, Angelo
2012-06-01
Global warming represents one of the most critical internationally perceived environmental issues. The growing, and increasingly global, wine sector is one of the industries which is under increasing pressure to adopt approaches for environmental assessment and reporting of product-related greenhouse gas emissions. The International Organization for Vine and Wine has recently recognized the need to develop a standard and objective methodology and a related tool for calculating carbon footprint (CF). This study applied this tool to a wine previously analyzed using the life cycle assessment (LCA) methodology. The objective was to test the tool as regards both its potential and possible limitations, and thus to assess its suitability as a standard tool. Despite the tool's user-friendliness, a number of limitations were noted including the lack of accurate baseline data, a partial system boundary and the impossibility of dealing with the multi-functionality issue. When the CF and LCA results are compared in absolute terms, large discrepancies become obvious due to a number of different assumptions, as well as the modeling framework adopted. Nonetheless, in relative terms the results seem to be quite consistent. However, a critical limitation of the CF methodology was its focus on a single issue, which can lead to burden shifting. In conclusion, the study confirmed the need for both further improvement and adaptation to additional contexts and further studies to validate the use of this tool in different companies.
Short, Sarah J.; Lubach, Gabriele R.; Shirtcliff, Elizabeth A.; Styner, Martin A.; Gilmore, John H.; Coe, Christopher L.
2014-01-01
Summary Population variation in hypothalamic-pituitary-adrenal (HPA) activity and reactivity was assessed in a healthy sample of 48 juvenile rhesus monkeys. Cluster analysis of the HPA profiles revealed four distinct neuroendocrine phenotypes based on six indices of HPA functioning. Behavioral reactivity was also evaluated in response to novel stimuli, and revealed marked differences between animals in the highest- and lowest-cortisol clusters. Specifically, animals in the high-cortisol cluster showed larger stress-induced cortisol responses and blunted feedback sensitivity to dexamethasone. They were also emotionally reactive, displayed more aggressive behaviors, and were less likely to approach novel objects. In contrast, monkeys in the low-cortisol cluster were more likely to approach and explore novel objects. Representative animals with high or low cortisol profiles were scanned with Magnetic Resonance Imaging to evaluate structural differences in global and regional gray matter (GM) and white matter (WM) volumes. Monkeys with higher cortisol reactivity evinced less hemispheric brain asymmetry, due to decreased GM in the right hemisphere. Stress reactivity was inversely related to global GM and positively related to total cerebrospinal fluid volume. This inverse relationship was also observed in several stress-sensitive regions, including prefrontal and frontal cortices. Our study demonstrates that population variation in pituitary-adrenal activity is related to behavioral disposition and cerebral structure in this nonhuman primate species. PMID:24954302
Robust Dynamic Multi-objective Vehicle Routing Optimization Method.
Guo, Yi-Nan; Cheng, Jian; Luo, Sha; Gong, Dun-Wei
2017-03-21
For dynamic multi-objective vehicle routing problems, the waiting time of vehicle, the number of serving vehicles, the total distance of routes were normally considered as the optimization objectives. Except for above objectives, fuel consumption that leads to the environmental pollution and energy consumption was focused on in this paper. Considering the vehicles' load and the driving distance, corresponding carbon emission model was built and set as an optimization objective. Dynamic multi-objective vehicle routing problems with hard time windows and randomly appeared dynamic customers, subsequently, were modeled. In existing planning methods, when the new service demand came up, global vehicle routing optimization method was triggered to find the optimal routes for non-served customers, which was time-consuming. Therefore, robust dynamic multi-objective vehicle routing method with two-phase is proposed. Three highlights of the novel method are: (i) After finding optimal robust virtual routes for all customers by adopting multi-objective particle swarm optimization in the first phase, static vehicle routes for static customers are formed by removing all dynamic customers from robust virtual routes in next phase. (ii)The dynamically appeared customers append to be served according to their service time and the vehicles' statues. Global vehicle routing optimization is triggered only when no suitable locations can be found for dynamic customers. (iii)A metric measuring the algorithms' robustness is given. The statistical results indicated that the routes obtained by the proposed method have better stability and robustness, but may be sub-optimum. Moreover, time-consuming global vehicle routing optimization is avoided as dynamic customers appear.
Wong, Chi Wah; Olafsson, Valur; Tal, Omer; Liu, Thomas T.
2012-01-01
Resting-state functional connectivity magnetic resonance imaging is proving to be an essential tool for the characterization of functional networks in the brain. Two of the major networks that have been identified are the default mode network (DMN) and the task positive network (TPN). Although prior work indicates that these two networks are anti-correlated, the findings are controversial because the anti-correlations are often found only after the application of a pre-processing step, known as global signal regression, that can produce artifactual anti-correlations. In this paper, we show that, for subjects studied in an eyes-closed rest state, caffeine can significantly enhance the detection of anti-correlations between the DMN and TPN without the need for global signal regression. In line with these findings, we find that caffeine also leads to widespread decreases in connectivity and global signal amplitude. Using a recently introduced geometric model of global signal effects, we demonstrate that these decreases are consistent with the removal of an additive global signal confound. In contrast to the effects observed in the eyes-closed rest state, caffeine did not lead to significant changes in global functional connectivity in the eyes-open rest state. PMID:22743194
Chai, Jeng-Da
2017-01-28
We propose hybrid schemes incorporating exact exchange into thermally assisted-occupation-density functional theory (TAO-DFT) [J.-D. Chai, J. Chem. Phys. 136, 154104 (2012)] for an improved description of nonlocal exchange effects. With a few simple modifications, global and range-separated hybrid functionals in Kohn-Sham density functional theory (KS-DFT) can be combined seamlessly with TAO-DFT. In comparison with global hybrid functionals in KS-DFT, the resulting global hybrid functionals in TAO-DFT yield promising performance for systems with strong static correlation effects (e.g., the dissociation of H 2 and N 2 , twisted ethylene, and electronic properties of linear acenes), while maintaining similar performance for systems without strong static correlation effects. Besides, a reasonably accurate description of noncovalent interactions can be efficiently achieved through the inclusion of dispersion corrections in hybrid TAO-DFT. Relative to semilocal density functionals in TAO-DFT, global hybrid functionals in TAO-DFT are generally superior in performance for a wide range of applications, such as thermochemistry, kinetics, reaction energies, and optimized geometries.
A role for the anterior insular cortex in the global neuronal workspace model of consciousness.
Michel, Matthias
2017-03-01
According to the global neuronal workspace model of consciousness, consciousness results from the global broadcast of information throughout the brain. The global neuronal workspace is mainly constituted by a fronto-parietal network. The anterior insular cortex is part of this global neuronal workspace, but the function of this region has not yet been defined within the global neuronal workspace model of consciousness. In this review, I hypothesize that the anterior insular cortex implements a cross-modal priority map, the function of which is to determine priorities for the processing of information and subsequent entrance in the global neuronal workspace. Copyright © 2017 Elsevier Inc. All rights reserved.
Hydrological excitation of polar motion
NASA Astrophysics Data System (ADS)
Nastula, Y.; Kolaczek, B.
2006-08-01
Hydrological excitation of the polar motion (HAM) were computed from the available recently hydrological data series (NCEP, ECMWF, CPC water storage and LaD World simulations of global continental water) and compared. Time variable seasonal spectra of these hydrological excitation functions and of the geodetic excitation function of polar motion computed from the polar motion COMB03 data were compared showing big differences in their temporal characteristics and the necessity of the further improvement of the HAM models. Seasonal oscillations of the global geophysical excitation functions (AAM + OAM + HAM) and their time variations were compared also. These hydrological excitation functions do not close the budget of the global geophysical excitation function of polar motion.
Adams, David; Suhr, Ole B; Dyck, Peter J; Litchy, William J; Leahy, Raina G; Chen, Jihong; Gollob, Jared; Coelho, Teresa
2017-09-11
Patisiran is an investigational RNA interference (RNAi) therapeutic in development for the treatment of hereditary ATTR (hATTR) amyloidosis, a progressive disease associated with significant disability, morbidity, and mortality. Here we describe the rationale and design of the Phase 3 APOLLO study, a randomized, double-blind, placebo-controlled, global study to evaluate the efficacy and safety of patisiran in patients with hATTR amyloidosis with polyneuropathy. Eligible patients are 18-85 years old with hATTR amyloidosis, investigator-estimated survival of ≥2 years, Neuropathy Impairment Score (NIS) of 5-130, and polyneuropathy disability score ≤IIIb. Patients are randomized 2:1 to receive either intravenous patisiran 0.3 mg/kg or placebo once every 3 weeks. The primary objective is to determine the efficacy of patisiran at 18 months based on the difference in the change in modified NIS+7 (a composite measure of motor strength, sensation, reflexes, nerve conduction, and autonomic function) between the patisiran and placebo groups. Secondary objectives are to evaluate the effect of patisiran on Norfolk-Diabetic Neuropathy quality of life questionnaire score, nutritional status (as evaluated by modified body mass index), motor function (as measured by NIS-weakness and timed 10-m walk test), and autonomic symptoms (as measured by the Composite Autonomic Symptom Score-31 questionnaire). Exploratory objectives include assessment of cardiac function and pathologic evaluation to assess nerve fiber innervation and amyloid burden. Safety of patisiran will be assessed throughout the study. APOLLO represents the largest randomized, Phase 3 study to date in patients with hATTR amyloidosis, with endpoints that capture the multisystemic nature of this disease. This trial is registered at clinicaltrials.gov ( NCT01960348 ); October 9, 2013.
Data inversion immune to cycle-skipping using AWI
NASA Astrophysics Data System (ADS)
Guasch, L.; Warner, M.; Umpleby, A.; Yao, G.; Morgan, J. V.
2014-12-01
Over the last decade, 3D Full Waveform Inversion (FWI) has become a standard model-building tool in exploration seismology, especially in oil and gas applications -thanks to the high quality (spatial density of sources and receivers) datasets acquired by the industry. FWI provides superior quantitative images than its travel-time counterparts (travel-time based inversion methods) because it aims to match all the information in the observations instead of a severely restricted subset of them, namely picked arrivals.The downside is that the solution space explored by FWI has a high number of local minima, and since the solution is restricted to local optimization methods (due to the objective function evaluation cost), the success of the inversion is subject to starting within the basin of attraction of the global minimum.Local minima can exist for a wide variety of reasons, and it seems unlikely that a formulation of the problem that can eliminate all of them -by defining the optimization problem in a form that results in a monotonic objective function- exist. However, a significant amount of local minima are created by the definition of data misfit. In its standard formulation FWI compares observed data (field data) with predicted data (generated with a synthetic model) by subtracting one from the other, and the objective function is defined as some norm of this difference. The combination of this criteria and the fact that seismic data is oscillatory produces the well-known phenomenon of cycle-skipping, where model updates try to match nearest cycles from one dataset to the other.In order to avoid cycle-skipping we propose a different comparison between observed and predicted data, based on Wiener filters, which exploits the fact that the "identity" Wiener filter is a spike at zero lag. This gives rise to a new objective function without cycle-skipped related local minima, and therefore suppress the need of accurate starting models or low frequencies in the data. This new technique, called Adaptive Waveform Inversion (AWI) appears always superior to conventional FWI.
Perioperative Assessment of Myocardial Deformation
Duncan, Andra E.; Alfirevic, Andrej; Sessler, Daniel I.; Popovic, Zoran B.; Thomas, James D.
2014-01-01
Evaluation of left ventricular performance improves risk assessment and guides anesthetic decisions. However, the most common echocardiographic measure of myocardial function, the left ventricular ejection fraction (LVEF), has important limitations. LVEF is limited by subjective interpretation which reduces accuracy and reproducibility, and LVEF assesses global function without characterizing regional myocardial abnormalities. An alternative objective echocardiographic measure of myocardial function is thus needed. Myocardial deformation analysis, which performs quantitative assessment of global and regional myocardial function, may be useful for perioperative care of surgical patients. Myocardial deformation analysis evaluates left ventricular mechanics by quantifying strain and strain rate. Strain describes percent change in myocardial length in the longitudinal (from base to apex) and circumferential (encircling the short-axis of the ventricle) direction and change in thickness in the radial direction. Segmental strain describes regional myocardial function. Strain is a negative number when the ventricle shortens longitudinally or circumferentially and is positive with radial thickening. Reference values for normal longitudinal strain from a recent meta-analysis using transthoracic echocardiography are (mean ± SD) −19.7 ± 0.4%, while radial and circumferential strain are 47.3 ± 1.9 and −23.3 ± 0.7%, respectively. The speed of myocardial deformation is also important and is characterized by strain rate. Longitudinal systolic strain rate in healthy subjects averages −1.10 ± 0.16 sec−1. Assessment of myocardial deformation requires consideration of both strain (change in deformation), which correlates with LVEF, and strain rate (speed of deformation), which correlates with rate of rise of left ventricular pressure (dP/dt). Myocardial deformation analysis also evaluates ventricular relaxation, twist, and untwist, providing new and noninvasive methods to assess components of myocardial systolic and diastolic function. Myocardial deformation analysis is based on either Doppler or a non-Doppler technique, called speckle-tracking echocardiography. Myocardial deformation analysis provides quantitative measures of global and regional myocardial function for use in the perioperative care of the surgical patient. For example, coronary graft occlusion after coronary artery bypass grafting is detected by an acute reduction in strain in the affected coronary artery territory. In addition, assessment of left ventricular mechanics detects underlying myocardial pathology before abnormalities become apparent on conventional echocardiography. Certainly, patients with aortic regurgitation demonstrate reduced longitudinal strain before reduction in LVEF occurs, which allows detection of subclinical left ventricular dysfunction and predicts increased risk for heart failure and impaired myocardial function after surgical repair. In this review we describe the principles, techniques, and clinical application of myocardial deformation analysis. PMID:24557101
Madrazo, Lorenzo; Lee, Claire B; McConnell, Meghan; Khamisa, Karima
2018-06-15
Physicians and medical students are generally poor-self assessors. Research suggests that this inaccuracy in self-assessment differs by gender among medical students whereby females underestimate their performance compared to their male counterparts. However, whether this gender difference in self-assessment is observable in low-stakes scenarios remains unclear. Our study's objective was to determine whether self-assessment differed between male and female medical students when compared to peer-assessment in a low-stakes objective structured clinical examination. Thirty-three (15 males, 18 females) third-year students participated in a 5-station mock objective structured clinical examination. Trained fourth-year student examiners scored their performance on a 6-point Likert-type global rating scale. Examinees also scored themselves using the same scale. To examine gender differences in medical students' self-assessment abilities, mean self-assessment global rating scores were compared with peer-assessment global rating scores using an independent samples t test. Overall, female students' self-assessment scores were significantly lower compared to peer-assessment (p < 0.001), whereas no significant difference was found between self- and peer-assessment scores for male examinees (p = 0.228). This study provides further evidence that underestimation in self-assessment among females is observable even in a low-stakes formative objective structured clinical examination facilitated by fellow medical students.
ERIC Educational Resources Information Center
Pan, Su-Yan
2006-01-01
A great deal of research has addressed the tension between economic globalization and local cultural identity, and the tension between convergence in global policy objectives and divergence in local practices, but research has not explored the impact of the complex interactions between these tensions on an individual university, especially in…
ERIC Educational Resources Information Center
Miller, Barbara, Ed.
This social studies unit suggests activities and teaching methods for use by seventh grade social studies classroom teachers as they develop and implement educational programs on global food, population, and energy problems. Objectives are to help students become aware of global interdependence, identify roles of various nations in causing and…
2011-03-01
These two elements again address the local and global perspectives of functionality. Upon schedule request, the Variable Ranking Tool ( VRT ) in...Figure 1 enlarges, moves to the interior of the screen, and becomes actionable (Figure 5 provides an enlarged view of the VRT , Figure 6 shows how the...full display is rearranged). The VRT addresses global properties through the handling of groups of entities in the system. Globally, functional
Tic Related Activity Restriction as a Predictor of Emotional Functioning and Quality of Life
Conelea, Christine A.; Busch, Andrew M.; Catanzaro, Mark A.; Budman, Cathy L.
2013-01-01
Objectives Tourette Syndrome (TS) is a chronic neuropsychiatric condition that frequently persists into adulthood. Existing research has identified demographic and symptom-level variables associated with psychopathology and poor quality of life in TS. However, behavior patterns associated with enhanced or adaptive psychological and global functioning among adults with TS have yet to be empirically identified. The current study examined whether tic-specific activity restriction is related to emotional functioning and quality of life in adults with TS. Methods Participants were 509 adults from the Tourette Syndrome Impact Survey who completed self-report measures of demographics, tic severity, emotional functioning, quality of life, and tic related general and social activity restriction. Results Partial correlations controlling for tic severity indicated that tic related general and social activity restriction were significantly correlated with lower quality of life and poorer emotional functioning. Hierarchical linear regression models indicated that activity restriction significantly predicted lower quality of life and poorer emotional functioning when controlling for tic severity and demographic variables. Conclusions Adults who restrict fewer activities due to tics, regardless of tic severity, experience greater quality of life and better emotional functioning. Clinically, adults with chronic tics may benefit from interventions focused on enhancing engagement in valued life activities. PMID:24156871
Global motion perception is associated with motor function in 2-year-old children.
Thompson, Benjamin; McKinlay, Christopher J D; Chakraborty, Arijit; Anstice, Nicola S; Jacobs, Robert J; Paudel, Nabin; Yu, Tzu-Ying; Ansell, Judith M; Wouldes, Trecia A; Harding, Jane E
2017-09-29
The dorsal visual processing stream that includes V1, motion sensitive area V5 and the posterior parietal lobe, supports visually guided motor function. Two recent studies have reported associations between global motion perception, a behavioural measure of processing in V5, and motor function in pre-school and school aged children. This indicates a relationship between visual and motor development and also supports the use of global motion perception to assess overall dorsal stream function in studies of human neurodevelopment. We investigated whether associations between vision and motor function were present at 2 years of age, a substantially earlier stage of development. The Bayley III test of Infant and Toddler Development and measures of vision including visual acuity (Cardiff Acuity Cards), stereopsis (Lang stereotest) and global motion perception were attempted in 404 2-year-old children (±4 weeks). Global motion perception (quantified as a motion coherence threshold) was assessed by observing optokinetic nystagmus in response to random dot kinematograms of varying coherence. Linear regression revealed that global motion perception was modestly, but statistically significantly associated with Bayley III composite motor (r 2 =0.06, P<0.001, n=375) and gross motor scores (r 2 =0.06, p<0.001, n=375). The associations remained significant when language score was included in the regression model. In addition, when language score was included in the model, stereopsis was significantly associated with composite motor and fine motor scores, but unaided visual acuity was not statistically significantly associated with any of the motor scores. These results demonstrate that global motion perception and binocular vision are associated with motor function at an early stage of development. Global motion perception can be used as a partial measure of dorsal stream function from early childhood. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Natarajan, Sundararajan
2014-12-01
The main objectives of the paper are to (1) present an overview of nonlocal integral elasticity and Aifantis gradient elasticity theory and (2) discuss the application of partition of unity methods to study the response of low-dimensional structures. We present different choices of approximation functions for gradient elasticity, namely Lagrange intepolants, moving least-squares approximants and non-uniform rational B-splines. Next, we employ these approximation functions to study the response of nanobeams based on Euler-Bernoulli and Timoshenko theories as well as to study nanoplates based on first-order shear deformation theory. The response of nanobeams and nanoplates is studied using Eringen's nonlocal elasticity theory. The influence of the nonlocal parameter, the beam and the plate aspect ratio and the boundary conditions on the global response is numerically studied. The influence of a crack on the axial vibration and buckling characteristics of nanobeams is also numerically studied.
Magnetic Activity Dependence of the Electric Drift Below L = 3
NASA Astrophysics Data System (ADS)
Lejosne, Solène; Mozer, F. S.
2018-05-01
More than 2 years of magnetic and electric field measurements by the Van Allen Probes are analyzed with the objective of determining the average effects of magnetic activity on the electric drift below L = 3. The study finds that an increase in magnetospheric convection leads to a decrease in the magnitude of the azimuthal component of the electric drift, especially in the nightside. The amplitude of the slowdown is a function of L, magnetic local time, and Kp, in a pattern consistent with the storm time dynamics of the ionosphere and thermosphere. To a lesser extent, magnetic activity also alters the average radial component of the electric drift below L = 3. A global picture for the average variations of the electric drift with Kp is provided as a function of L and magnetic local time. It is the first time that the signature of the ionospheric disturbance dynamo is observed in near-equatorial electric drift measurements.