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Oelz Dietmar - - 2013
A mathematical model in one dimension for a non-sarcomeric actomyosin bundle featuring anti-parallel flows of anti-parallel F-actin is introduced. The model is able to relate these flows to the effect of cross-linking and bundling proteins, to the forces due to myosin-II filaments and to external forces at the extreme tips ...
Stadler T - - 2013
Phylogenetic trees of only extant species contain information about the underlying speciation and extinction pattern. In this review, I provide an overview over the different methodologies that recover the speciation and extinction dynamics from phylogenetic trees. Broadly, the methods can be divided into two classes: (i) methods using the phylogenetic ...
Scotti Luciana - - 2013
The mosquito Aedes aegypti (Diptera, Culicidae) is the vector of yellow and dengue fever. In this study, chemometric tools, such as, Principal Component Analysis (PCA), Consensus PCA (CPCA), and Partial Least Squares Regression (PLS), were applied to a set of fifty five active compounds against Ae. aegypti larvae, which includes ...
Hernandez-Aguilar R Adriana - - 2013
Data on chimpanzee (Pan troglodytes) nesting patterns were collected in Issa, Ugalla, western Tanzania. Ugalla is one of the driest, most open, and seasonal habitats inhabited by chimpanzees. We investigated the physical characteristics of nests and trees used for nesting to understand environmental influences on nest building and identify the ...
Ferreira Alexandre F P - - 2013
We study the adsorption equilibrium isotherms and differential heats of adsorption of hexane isomers on the zeolitic imidazolate framework ZIF-8. The studies are carried out at 373 K using a manometric set-up combined with a micro-calorimeter. We see that the Langmuir model describes well the isotherms for all four isomers ...
Stenroos Matti - - 2013
The conductivity profile of the head has a major effect on EEG signals, but unfortunately the conductivity for the most important compartment, skull, is only poorly known. In dipole modelling studies, errors in modelled skull conductivity have been considered to have a detrimental effect on EEG source estimation. However, as ...
de Queiroz Kevin - - 2013
Adopting the perspective of graph theory, Martin et al. (2010) described two kinds of phylogenetic trees, which they termed node-based and stem- or branch-based, that differ with respect to the biological interpretations of their component nodes and branches. After establishing equivalency between the two different kinds of trees in terms ...
Kitsche Andreas - - 2013
Profile hidden Markov models (HMMs) were used to predict the configuration of secondary alcohols and α-methyl branches of modular polyketides. Based on the configurations of two chiral centers in these polyketides, 78 ketoreductases were classified into four different types of polyketide producers. The identification of positions that discriminate between these ...
Karalis Vangelis - - 2013
PURPOSE: Unveil the properties of a two-stage design (TSD) for bioequivalence (BE) studies. METHODS: A TSD with an upper sample size limit (UL) is described and analyzed under different conditions using Monte Carlo simulations. TSD was split into three branches: A, B1, and B2. The first stage included branches A ...
Gharib Walid H - - 2013
Positive selection is widely estimated from protein coding sequences by the non synonymous / synonymous ratio ω. Increasingly elaborate codon models are used in a likelihood framework for this estimation. While there is widespread concern about the robustness of the estimation of the ω ratio, more efforts are needed to ...
Oliveira W W - - 2013
In this paper we compare different compression models for authorship attribution. To this end, three different types of compressors, Lempel-Ziv type (GZip), block sorting type (BZip) and statistical type (PPM), along with two different similarity measures were considered in our experiments. Besides, two different attribution methods are analyzed in this ...
Friede Tim - - 2013
The internal pilot study design allows for modifying the sample size during an ongoing study based on a blinded estimate of the variance thus maintaining the trial integrity. Various blinded sample size re-estimation procedures have been proposed in the literature. We compare the blinded sample size re-estimation procedures based on ...
Song Xiaofeng - - 2013
In addition to experimental identification of pre-miRNAs, the computational prediction method is also becoming a hot research spot. Most existing prediction methods are usually excluding those pre-miRNAs with multiple loops. But as more and more miRNA have been identified, quite a number of miRNA precursor with multiple loops have been ...
Zaghetto A - - 2013
This paper proposes a hybrid pattern matching/transform-based compression method for scanned documents. The idea is to use regular video interframe prediction as a pattern matching algorithm that can be applied to document coding. We show that this interpretation may generate residual data that can be efficiently compressed by a transform-based ...
Sommer David E - - 2013
Block-type lumped-element models of the vocal folds are widely used for speech investigations due in part to the rich dynamics exhibited over a range of input parameters, particularly for asymmetric tissue properties. While self-consistent in derivation and application, block-type models of the vocal fold masses are inherently susceptible to non-physical ...
Suleymanov Y - - 2013
A mathematical model is developed to describe and investigate interstitial branching of axonal networks during nervous system development. The model under consideration describes axonal network growth in which the concentration of axon guidance molecules controls axon's growth and interstitial branching from axon shaft. Numerical simulations show that in the model ...
Crawford Forrest W - - 2013
The branching structure of biological evolution confers statistical dependencies on phenotypic trait values in related organisms. For this reason, comparative macroevolutionary studies usually begin with an inferred phylogeny that describes the evolutionary relationships of the organisms of interest. The probability of the observed trait data can be computed by assuming ...
Antoneli Fernando - - 2013
In this paper, we revisit and adapt to viral evolution an approach based on the theory of branching process advanced by Demetrius et al. (Bull. Math. Biol. 46:239-262, 1985), in their study of polynucleotide evolution. By taking into account beneficial effects, we obtain a non-trivial multivariate generalization of their single-type ...
Hon Nicholas - - 2013
The effect of target probability on detection times is well-established: Even when detection accuracy is high, lower probability targets are detected more slowly than higher probability ones. Although this target probability effect on detection times has been well-studied, one aspect of it has remained largely unexamined: How the effect develops ...
Aichholzer Oswin - - 2013
Given a set B of n black points in general position, we say that a set of white points W blocks B if in the Delaunay triangulation of [Formula: see text] there is no edge connecting two black points. We give the following bounds for the size of the smallest ...
Long Tao - - 2013
This paper studies the problem of single-channel noise reduction in the time domain and presents a block-based approach where a vector of the desired speech signal is recovered by filtering a frame of the noisy signal with a rectangular filtering matrix. With this formulation, the noise reduction problem becomes one ...
Schouteden Martijn - - 2013
Often data are collected that consist of different blocks that all contain information about the same entities (e.g., items, persons, or situations). In order to unveil both information that is common to all data blocks and information that is distinctive for one or a few of them, an integrated analysis ...
Faes Luca - - 2013
In the past years, several frequency-domain causality measures based on vector autoregressive time series modeling have been suggested to assess directional connectivity in neural systems. The most followed approaches are based on representing the considered set of multiple time series as a realization of two or three vector-valued processes, yielding ...
Lane Stephanie T - - 2013
Startle habituation is present in all startle studies, whether as a dependent variable, discarded habituation block, or ignored nuisance. However, there is still much that remains unknown about startle habituation, including: (1) what is the nature of the startle habituation curve?; (2) at what point does startle habituation approach an ...
Morgan John W R - - 2013
A model potential for colloidal building blocks is defined with two different types of attractive surface sites, described as complementary patches and antipatches. A Bernal spiral is identified as the global minimum for clusters with appropriate arrangements of three patch-antipatch pairs. We further derive a minimalist design rule with only ...
Zhang Xingyou - - 2013
Traditional survey methods for obtaining nationwide small-area estimates (SAEs) of childhood obesity are costly. This study applied a geocoded national health survey in a multilevel modeling framework to estimate prevalence of childhood obesity at the census block-group level. We constructed a multilevel logistic regression model to evaluate the influence of ...
Joppa Lucas N - - 2013
BACKGROUND: Networks of single interaction types, such as plant-pollinator mutualisms, are biodiversity's "building blocks". Yet, the structure of mutualistic and antagonistic networks differs, leaving no unified modeling framework across biodiversity's component pieces. METHODSPRINCIPAL FINDINGS: We use a one-dimensional "niche model" to predict antagonistic and mutualistic species interactions, finding that accuracy ...
Neaux Dimitri - - 2013
The organization of the bony face is complex, its morphology being influenced in part by the rest of the cranium. Characterizing the facial morphological variation and craniofacial covariation patterns in extant hominids is fundamental to the understanding of their evolutionary history. Numerous studies on hominid facial shape have proposed hypotheses ...
Ng Ying Woo - - 2013
Introduction: This study aimed to develop a realistic and lifelike uterine model for the training of hysteroscopy skills. Materials and Methods: A lifelike "uterine" model was constructed using female pig bladder. The pig bladder was enclosed within a malleable mould, with both ureters blocked by pins. Both rigid and fl ...
Bapst David W - - 2013
Morphology-based phylogenetic analyses are the only option for reconstructing relationships among extinct lineages, but often find support for conflicting hypotheses of relationships. The resulting lack of phylogenetic resolution is generally explained in terms of data quality and methodological issues, such as character selection. A previous suggestion is that sampling ancestral ...
Kello Christopher T - - 2013
It is now well-established that intrinsic variations in human neural and behavioral activity tend to exhibit scaling laws in their fluctuations and distributions. The meaning of these scaling laws is an ongoing matter of debate between isolable causes versus pervasive causes. A spiking neural network model is presented that self-tunes ...
De Roover Kim - - 2013
In many fields of research, so-called 'multiblock' data are collected, i.e., data containing multivariate observations that are nested within higher-level research units (e.g., inhabitants of different countries). Each higher-level unit (e.g., country) then corresponds to a 'data block'. For such data, it may be interesting to investigate the extent to ...
Ma Zhenjun - - 2012
The balance of important baseline covariates is essential for convincing treatment comparisons. Stratified permuted block design and minimization are the two most commonly used balancing strategies, both of which require the covariates to be discrete. Continuous covariates are typically discretized in order to be included in the randomization scheme. But ...
Foda Abd Al-Rahman Mohammad - - 2012
Manual tissue microarray (TMA) construction had been introduced to avoid the high cost of automated and semiautomated techniques. The cheapest and simplest technique for constructing manual TMA was that of using mechanical pencil tips. This study was carried out to modify this method, aiming to raise its quality to reach ...
Blasinski H - - 2012
We propose a color barcode framework for mobile phone applications by exploiting the spectral diversity afforded by the cyan (C), magenta (M), and yellow (Y) print colorant channels commonly used for color printing and the complementary red (R), green (G), and blue (B) channels, respectively, used for capturing color images. ...
Orendorff David - - 2012
A new algorithm, "HiER-leap" (hierarchical exact reaction-leaping), is derived which improves on the computational properties of the ER-leap algorithm for exact accelerated simulation of stochastic chemical kinetics. Unlike ER-leap, HiER-leap utilizes a hierarchical or divide-and-conquer organization of reaction channels into tightly coupled "blocks" and is thereby able to speed up ...
Kremling Andreas - - 2012
ABSTRACT: BACKGROUND: Signal transduction plays a fundamental role in the understanding of cellular physiology. The bacterialphosphotransferase system (PTS) together with the PEP/pyruvate node in central metabolism represents asignaling unit that acts as a sensory element and measures the activity of the central metabolism.Pseudomonas putida possesses two PTS branches, the C-branch ...
Peña Javier - - 2012
ABSTRACT: The aim of this study was to determine which skills and factors better predicted the outcomes of regular season volleyball matches in the Spanish "Superliga" and were significant for obtaining positive results in the game. The study sample consisted of 125 matches played during the 2010-2011 Spanish men's first ...
Bao Xiao-Lei - - 2012
Multifactor designs that are able to examine the interactions include factorial design, factorial design with a block factor, repeated measurement design; orthogonal design, split-block design, etc. Among all the above design types that are able to examine the interactions, the factorial design is the most commonly used. It is also ...
Doerk Gregory S - - 2012
The realization of viable designs for circuit patterns using the dense features formed by block copolymer directed self-assembly (DSA) will require precise and quantitative understanding of self-assembled feature registration to guiding templates or chemical prepatterns. Here we report measurements of DSA placement error for lamellar block copolymer domains indexed to ...
Tallman Melissa - - 2012
Researchers often attempt to use limb proportions to ascertain the locomotor repertoires of fossil hominins. This can be problematic as there are few skeletons in the fossil record that preserve both a full forelimb and hindlimb; therefore, estimates of full limb lengths are typically associated with substantial error. In this ...
Poolkhet C - - 2012
The aim of this study is to explain the social networks of the backyard chicken in Ratchaburi, Suphan Buri and Nakhon Pathom Provinces. In this study, we designed the nodes as groups of persons or places involved in activities relating to backyard chickens. The ties are all activities related to ...
Michalek Pavel - - 2012
PURPOSE: Infraorbital nerve block is used for intraoperative and postoperative analgesia in nasal and oral surgery procedures, as well as in the chronic pain settings. Ultrasound guidance has not been described in the literature. The aim of the study was to assess the quality of ultrasound imaging of the infraorbital ...
Posé Nicolas - - 2012
We performed numerical simulations of the q-state Potts model to compute the reduced conductivity exponent t/ν for the critical Coniglio-Klein clusters in two dimensions, for values of q in the range [1,4]. At criticality, at least for q<4, the conductivity scales as C(L)∼L^{-t/ν}, where t and ν are, respectively, the ...
Parra-Robles Juan - - 2012
Hyperpolarized (3)He diffusion experiments have been shown to be sensitive to changes in acinar structure due to emphysematous lung disease. Extracting quantitative information about lung microstructure from the diffusion signal is complicated due its dependence on a number of factors including diffusion time and the complex branching acinar geometry. A ...
Zhang Z - - 2012
Fetal ECG (FECG) telemonitoring is an important branch in telemedicine. The design of a telemonitoring system via a wireless body-area network with low energy consumption for ambulatory use is highly desirable. As an emerging technique, compressed sensing (CS) shows great promise in compressing/ reconstructing data with low energy consumption. However, ...
Ge Bao - - 2012
Clustering streamline fibers derived from diffusion tensor imaging (DTI) data into functionally meaningful bundles with group-wise correspondences across individuals and populations has been a fundamental step for tract-based analysis of white matter integrity and brain connectivity modeling. Many approaches of fiber clustering reported in the literature so far used geometric ...
Lin Yu - - 2012
SUMMARY: TIBA is a tool to reconstruct phylogenetic trees from rearragement data which consists of ordered lists of synteny blocks (or genes) where each synteny block is shared with all of its homologs in the input genomes. The evolution of these synteny blocks, through rearrangement operations, is modeled by the ...
Kukreti B M - - 2012
With the objective to affirm the apparent uranium ore zone grade/thickness with good confidence for the non-cored as well as those boreholes with poor core recovery in the sedimentary environment of Wahkut block, West Khasi Hills district of Meghalaya, a systematic study between the in situ measured γ-ray logs under ...
Hergarten Stefan - - 2012
A self-organized critical branching process based on a local interaction rule is presented. In accordance with the self-organized branching process model introduced by Zapperi, Lauritsen, and Stanley, its event-size distribution follows a power law with scaling exponent τ=3/2, but the new model does not require a global variable to self-organize ...
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