Recently, resting-state functional magnetic resonance imaging has been used to parcellate the brain into functionally distinct regions based on the information available in functional connectivity maps. However, brain voxels are not independent units and adjacent voxels are always highly correlated, so functional connectivity maps contain redundant information, which not only ...

The biodiversity-ecosystem functioning (BEF) relationship is central in community ecology. Its drivers in competitive systems (sampling effect and functional complementarity) are intuitive and elegant, but we lack an integrative understanding of these drivers in complex ecosystems. Because networks encompass two key components of the BEF relationship (species richness and biomass ...

One key problem in computational neuroscience and neural engineering is the identification and modeling of functional connectivity in the brain using spike train data. To reduce model complexity, alleviate overfitting, and thus facilitate model interpretation, sparse representation and estimation of functional connectivity is needed. Sparsities include global sparsity, which captures ...

Medical cost data are often skewed to the right and heteroscedastic, having a nonlinear relation with covariates. To tackle these issues, we consider an extension to generalized linear models by assuming nonlinear associations of covariates in the mean function and allowing the variance to be an unknown but smooth function ...

In this article, we offer a new, macroergonomics perspective on the long-debated issue of function allocation. We believe thinking in this domain needs to be realigned, moving away from the traditional microergonomics conceptualisation, concerned predominantly with task-based decisions, and towards a macroergonomics approach, viewing function allocation choices as central to ...

The exponential distribution is frequently used to model the survival time of a patient population, which assumes the hazard rate to be a constant over time. This assumption is often violated as the hazard function may vary over time and exhibit one or more change points in its values. Several ...

A comparison model is proposed based on the Löwdin partitioning technique to analyze the differences in the treatment of electron correlation by the wave function and density functional models. This comparison model provides a tool to understand the inherent structure of both theories and its discrepancies in terms of the ...

We consider the problem of variable selection for monotone single-index models. A single-index model assumes that the expectation of the outcome is an unknown function of a linear combination of covariates. Assuming monotonicity of the unknown function is often reasonable and allows for more straightforward inference. We present an adaptive ...

When a transducer is an immutable component of a larger system being simulated, it is sufficient that the transducer model correctly reproduce behavior only at the available ports of the transducer. The behavior of two-port electroacoustic transducer should be completely characterized by three transfer functions related to the electrical and ...

Head-related transfer function (HRTF) individualization using principle component analysis (PCA) modeling rely on the empirical data to reduce HRTF dimensionality for an optimal representation and to achieve HRTF personalization by tuning the model weights with the subject anthropometric parameters. However, for these representations, the basis is discrete and data dependent, ...

With the increasing availability of advanced imaging technologies, we are entering a new era of neuroscience. Detailed descriptions of the complex brain network enable us to map out a structural connectome, characterize it with graph theoretical methods, and compare it to the functional networks with increasing detail. To link these ...

In his famous "deathbed" letter, Ramanujan "defined" the notion of a mock theta function and offered some examples of functions he believed satisfied his definition. Very recently, Griffin et al. established for the first time that Ramanujan's mock theta functions actually satisfy his own definition. On the other hand, Zwegers' ...

Microbes play an essential role in ecosystem functions, including carrying out biogeochemical cycles, but are currently considered a black box in predictive models and all global biodiversity debates. This is due to: (i) perceived temporal and spatial variations in microbial communities; (ii) lack of ecological theory explaining how microbes regulate ...

SUMMARY: RSVSim is a tool for the simulation of deletions, insertions, inversions, tandem duplications and translocations of various sizes in any genome available as FASTA-file or data package in R. The structural variations (SVs) can be generated randomly, based upon user-supplied genomic coordinates or associated to various kinds of repeats. ...

Bayesian ARTMAP (BA) is a recently introduced neural architecture which uses a combination of Fuzzy ARTMAP competitive learning and Bayesian learning. Training is generally performed online, in a single-epoch. During training, BA creates input data clusters as Gaussian categories, and also infers the conditional probabilities between input patterns and categories, ...

BACKGROUND: Despite the developmental impact of chromosome segregation errors, we lack the tools to assess environmental effects on the integrity of the germline in animals. OBJECTIVES: Here, we report the development of an assay in C. elegans that fluorescently marks aneuploid embryos following chemical exposure. METHODS: We qualified the predictive ...

The cerebellum is commonly studied in the context of the classical eyeblink conditioning model, which attributes an adaptive motor function to cerebellar learning processes. This model of cerebellar function has quite a few shortcomings and may in fact be somewhat deficient in explaining the myriad functions attributed to the cerebellum, ...

Behaviour modification procedures for challenging behaviour, based on principles of operant learning, benefit from an accurate appraisal of behavioural function. Numerous methods of direct and indirect functional assessment exist, which have relative strengths and weaknesses. In this study, structured descriptive assessments were used to identify the function of challenging behaviour. ...

Understanding the functional significance of species interactions in ecosystems has become a major challenge as biodiversity declines rapidly worldwide. Ecosystem consequences arising from the loss of diversity either within trophic levels (horizontal diversity) or across trophic levels (vertical diversity) are well documented. However, simultaneous losses of species at different trophic ...

A core goal of human connectomics is to characterize the neural pathways that underlie brain function. This can be largely achieved noninvasively by inferring white matter connectivity using diffusion MRI data. However, there are challenges. First, diffusion tractography is blind to directed connections, or whether a connection is expressed functionally. ...

SUMMARY: Structural modeling of biochemical networks enables qualitative as well as quantitative analysis of those networks. Automated network decomposition into functional modules is a crucial point in network analysis. Although there exist approaches for the analysis of networks, there is no open source tool available that combines editing, visualization, and ...

Independent component analysis (ICA) has been widely used in functional magnetic resonance imaging (fMRI) data to evaluate the functional connectivity, which assumes that the sources of functional networks are statistically independent. Recently, many researchers have demonstrated that sparsity is an effective assumption for fMRI signal separation. In this research, we ...

The essence of biological phenomena appears in form and function: "Form follows function." Mathematically, G x M → M, where G contains the parameters of the action and M is the form. The Mathematics for this purpose is largely available and is well described in a recent book (Felix et ...

The team functioning assessment tool (TFAT) has been shown to be a reliable behavioral marker tool for assessing nontechnical skills that are critical to the success of ward-based healthcare teams. This paper aims to refine and shorten the length of the TFAT to improve usability, and establish its reliability and ...

The motivation behind the development of a new interactive three-dimensional (3D) model of the cartilaginous and bony framework of the nose originated from the significant demand for sophisticated patient communication and for accurate documentation of the surgical steps in rhinoplasty. Basically, the model consists of three features-the viewer function, the ...

A two-step agent-based mathematical model of negative rumor spread in the context of conflicting groups is presented. The GBN-Dialogue model builds on rumor theory, focuses on person-to-person interaction characteristics,and is dynamical. The model first estimates the probability of rumor transmission between two persons based on their transmission motivation (which is ...

We introduce a novel implicit representation for 2D and 3D shapes based on Support Vector Machine (SVM) theory. Each shape is represented by an analytic decision function obtained by training SVM, with a Radial Basis Function (RBF) kernel so that the interior shape points are given higher values. This empowers ...

We applaud Bullot & Reber's (B&R's) attempt to encompass the function of artworks within their psycho-historical model of art appreciation. However, we suggest that in order to fully realize this aim, they require a clearer distinction between an artist's intentions toward an artwork and its proper functions. We also show ...

Gene Ontology (GO) is a hierarchical vocabulary for the description of biological functions and locations, often employed by computational methods for protein function prediction. Due to the structure of GO, function predictions can be self- contradictory. For example, a protein may be predicted to belong to a detailed functional class, ...

A Bayesian alignment model (BAM) is proposed for alignment of liquid chromatography-mass spectrometry (LC-MS) data. BAM belongs to the category of profile-based approaches, which are composed of two major components: a prototype function and a set of mapping functions. Appropriate estimation of these functions is crucial for good alignment results. ...

MOTIVATION: Computational biologists have demonstrated the utility of using machine learning methods to predict protein function from an integration of multiple genome-wide data types. Yet even the best performing function prediction algorithms rely on heuristics for important components of the algorithm, such as choosing negative examples (proteins without a given ...

BACKGROUND: Functional data analysis (FDA) is increasingly being used to better analyze, model and predict time series data. Key aspects of FDA include the choice of smoothing technique, data reduction, adjustment for clustering, functional linear modeling and forecasting methods. METHODS: A systematic review using 11 electronic databases was conducted to ...

Tree comparison functions are widely used in phylogenetics for comparing trees. Unrooted trees can be compared with rooted trees by identifying all rootings that minimize a given cost function between two rooted trees. The plateau property is satisfied by the provided function, if all optimal rootings form a subtree, or ...

At present, there are many studies that collect information on aspects of neurologic and behavioral function (cognition, sensation, movement, emotion), but with little uniformity among the measures used to capture these constructs. Further, available measures are generally expensive, normed on homogenous nondiverse populations, not easily administered, do not cover the ...

Workload capacity, an important concept in many areas of psychology, describes processing efficiency across changes in workload. The capacity coefficient is a function across time that provides a useful measure of this construct. Until now, most analyses of the capacity coefficient have focused on the magnitude of this function, and ...

Abstract Differences in trait composition, or functional structure, of assemblages across spatial scales may stem from the ability to tolerate local conditions (environmental filters) and from assembly rules (biological filters). However, disentangling their respective roles has proven difficult, and limited generalities have emerged from research on the spatial scaling of ...

Two steepest-descent algorithms with momentum for quadratic functions are considered. For a given learning rate, the sufficient and necessary conditions for the semistability of the steepest-descent algorithms with momentum are established. Moreover, the optimal momentum factors that generally make for the fastest convergence are obtained.

A semi-parametric model for estimating hemodynamic response function (HRF) from multi-subject fMRI data is introduced within the context of the General Linear Model. The new model assumes that the HRFs for a fixed brain voxel under a given stimulus share the same unknown functional form across subjects, but differ in ...

Assessment for the purpose of monitoring change over time requires a different practical and statistical approach to that of assessment for diagnosing impairment. Sophisticated methods exist for identifying strengths and weaknesses in a patient's voice/speech profile, yet our understanding of the impact of repeated assessment is limited. Monitoring change necessitates ...

Two speech functions have traditionally been ascribed to the velum: opening and closing the velopharyngeal port and providing a passive surface against which the tongue can produce oral constrictions. Contrary to this passive oral function, the present x-ray study finds that a substantial portion of the velum moves to constrict ...

Many children with ADHD remain symptomatic in (young) adulthood. It is important to understand what characterizes this persistent ADHD group. Since ADHD has been associated with neurocognitive dysfunctioning on a variety of neurocognitive domains, and many of these domains are influenced by the same risk genes that influence ADHD, neurocognitive ...

Spatial Cox point processes is a natural framework for quantifying the various sources of variation governing the spatial distribution of rain forest trees. We introduce a general criterion for variance decomposition for spatial Cox processes and apply it to specific Cox process models with additive or log linear random intensity ...

We demonstrate that within the framework of the hinge model, the polarization mode dispersion (PMD) vector correlation function averaged over time and wavelength is only appreciably affected by the position of the last hinge. Further, the correlation function width is found within the context of a standard hinge model to ...

Abstract Functional statistics are commonly used to characterize spatial patterns in general and spatial genetic structures in population genetics in particular. Such functional statistics also enable the estimation of parameters of spatially explicit (and genetic) models. Recently, Approximate Bayesian Computation (ABC) has been proposed to estimate model parameters from functional ...

Functional shifts during protein evolution are expected to yield shifts in substitution rate, and statistical methods can test for this at both codon and amino acid levels. Although methods based on models of sequence evolution serve as powerful tools for studying evolutionary processes, violating underlying assumptions can lead to false ...

Executive functions play a vital role in the everyday functioning of healthy individuals across the lifespan and have been implicated in a wide variety of clinical conditions. Historically, the assessment of executive functions in clinical and research settings relied on performance-based measures. A number of authors have argued, however, that ...

In this article we review the current status of executive function as a concept, its development, and its assessment during development. Following the review of key issues, we make recommendations for improved conceptualization and definition-the precursors to improved models of assessment of executive functioning.

Numerous cortical disorders affect language. We explore the connection between the observed language behavior and the underlying substrates by adopting a neurocomputational approach. To represent the observed trajectories of the discourse in patients with disorganized speech and in healthy participants, we design a graphical representation for the discourse as a ...

AIMS: Understanding the exact relationship between serum thyrotropin/thyroid stimulating hormone (TSH) and free thyroxine (FT(4)) is a prerequisite for improving diagnostic reliability and clinical decision making. METHODS: We (1) retrospectively studied the relationship between TSH and FT(4) in a large unselected clinical sample (n=6641) of primary hypothyroid, euthyroid and hyperthyroid ...

The overall goal of this work is to demonstrate how resting state functional magnetic resonance imaging (fMRI) signals may be used to objectively parcellate functionally heterogeneous subregions of the human amygdala into structures characterized by similar patterns of functional connectivity. We hypothesize that similarity of functional connectivity of subregions with ...