text:
- Methodology article
- Open Access
Global parameter estimation methods for stochastic biochemical systems
- Suresh Kumar Poovathingal1 and
- Rudiyanto Gunawan1Email author
© Poovathingal and Gunawan; licensee BioMed Central Ltd. 2010
- Received: 21 June 2010
- Accepted: 6 August 2010
- Published: 6 August 2010
The importance of stochasticity in cellular processes having low number of molecules has resulted in the development of stochastic models such as chemical master equation. As in other modelling frameworks, the accompanying rate constants are important for the end-applications like analyzing system properties (e.g. robustness) or predicting the effects of genetic perturbations. Prior knowledge of kinetic constants is usually limited and the model identification routine typically includes parameter estimation from experimental data. Although the subject of parameter estimation is well-established for deterministic models, it is not yet routine for the chemical master equation. In addition, recent advances in measurement technology have made the quantification of genetic substrates possible to single molecular levels. Thus, the purpose of this work is to develop practical and effective methods for estimating kinetic model parameters in the chemical master equation and other stochastic models from single cell and cell population experimental data.
Three parameter estimation methods are proposed based on the maximum likelihood and density function distance, including probability and cumulative density functions. Since stochastic models such as chemical master equations are typically solved using a Monte Carlo approach in which only a finite number of Monte Carlo realizations are computationally practical, specific considerations are given to account for the effect of finite sampling in the histogram binning of the state density functions. Applications to three practical case studies showed that while maximum likelihood method can effectively handle low replicate measurements, the density function distance methods, particularly the cumulative density function distance estimation, are more robust in estimating the parameters with consistently higher accuracy, even for systems showing multimodality.
The parameter estimation methodologies described in this work have provided an effective and practical approach in the estimation of kinetic parameters of stochastic systems from either sparse or dense cell population data. Nevertheless, similar to kinetic parameter estimation in other modelling frameworks, not all parameters can be estimated accurately, which is a common problem arising from the lack of complete parameter identifiability from the available data.
- Probability Density Function
- Differential Evolution
- Cumulative Density Function
- Population Member
- Parameter Estimation Method
Mathematical models form a cornerstone of systems biology and these models are usually constructed from available biological knowledge and data, which once validated, are subsequently analyzed to address specific biological questions. Many canonical modelling frameworks, from statistical Bayesian networks to differential equations, have been applied to capture a wide-variety of biological behaviours. Specifically, the dynamics related to cellular processes that involve low copy number of molecules, such as mRNA transcription, are best described as random and noisy events [1]. For example, cells in an iso-genetic population do not necessarily assume the same biological state, but rather exhibit variegated genetic expressions [2, 3]. In these examples, the distribution of cells is simulated by stochastic models that describe the probability density function (PDF) of cellular states. However, unlike differential equation models, the identification of stochastic models from experimental data of single cell or cell population data are not yet routine.
Despite the availability of high-throughput cell biology, the estimation of unknown (kinetic) model parameters from experimental data is still considered as the bottleneck in biological model identification, especially for dynamical models [4, 5]. The difficulty is generally attributed to the informativeness of the data, or the lack thereof, a property that is proportional to not only the quantity, but also the quality of data. Furthermore, in dynamical models, the time resolution of data is naturally of great importance. In recent years, advances in bio-imaging allow for real time measurements of cellular components such as mRNAs and proteins in individual cells through the use of fluorescent proteins [2, 3, 6–8]. Such measurements provide more in-depth and informative data about the states of a cell and variability in a cell population, than the traditional lumped measurements from cell culture lysate or tissue homogenate. The purpose of this work is to develop practical methods that can efficiently use these data in the parameter estimation framework for stochastic biochemical systems.
Chemical master equation (CME) is the most commonly adopted modelling framework to describe stochastic cellular dynamics [1–3] and thus is used as a benchmark application in this work. The estimation of unknown kinetic parameters from data in CME and other stochastic models has not been adequately addressed in the literature. Many of the published CME models use rate constants that are scaled from deterministic parameter values or selected ad-hoc to replicate desired behaviour. Since the low-copy-number random events can generate dynamics that are characteristically different from those in thermodynamic or deterministic limit [9, 10], deterministic model parameters identified from data collected under this limit or averaged over cell populations can be misleading. Furthermore, fitting deterministic models (e.g. ordinary differential equation) to stochastic data has been shown to give poor parameter estimates and model prediction [11]. Among the existing parameter estimation methods for stochastic biological models, some rely on Bayesian inference based on the stochastic differential equation [12, 13], while others are based on maximum likelihood (ML) methods. One ML method obtains parameter estimates by fitting transition density functions of stochastic differential equations in biochemical pathways [11]. A similar approach based on the ML of transitional probabilities requires measurements of the state trajectories at very fast sampling rate, whereby reactions are assumed to occur at most twice in a sampling time interval [14]. The fast sampling requirement makes this approach impractical, since biological data are typically sparse.
In this work, three kinetic parameter estimation methods for stochastic models were developed based on two criteria: maximum likelihood (ML) and density function distance (DFD). Two scenarios of practical application were considered involving both sparsely and densely populated datasets (i.e. low and high replicates). Since the distribution density functions are commonly constructed using histograms, an important aspect related to the binning strategy and the noise associated with finite sampling, has been incorporated in the parameter estimation framework. The efficacy of each method was evaluated and compared based on applications to three CME case studies: RNA dynamics in Escherichia coli, gene expression network of galactose uptake model in Saccharomyces cerevisiae, and a bimodal system comprising of a genetic toggle switch in E. coli. Despite the use of CME models here, the methods are generally applicable to other stochastic models in which the system behaviour or output can be characterized by a PDF of the states.
Chemical Master Equation
where the state x is an N-dimensional vector indicating the number of molecules of each species in the volume Ω, the density function P(x, t|x0, t0) denotes the probability that the system assumes the state configuration x j at time t, given the initial condition x0 at time t0, the vector ν j gives the stoichiometric change in the molecular count of each species due to a single j-th reaction event, and k is the kinetic parameter vector. The function a j (x, k) is known as the propensity function, where a j (x, k)dt gives the probability of the j-th reaction to occur in the time interval t and t+ dt given the state x and parameters k. Due to the curse of dimensionality with increasing number of reacting species, the analytical solution of a CME is usually difficult, if not practically impossible, to obtain even for moderately sized systems [16].
In this work, Stochastic Simulation Algorithm (SSA) [16] was used to generate in silico experimental data for the purpose of parameter estimation and to solve for the PDF of the CME model. Briefly, at any given time and state configuration, the algorithm takes two uniform random numbers, from which the time to the next reaction and the reaction index are determined as a function of the propensities [16, 17]. The histogram should reflect the true state PDF in the limit of the number of realizations tending to infinity. Since only a finite number of data samples are computationally feasible and experimentally practical, the error associated with histogram binning strategy is important, but this is not often discussed in existing literature of the CME. The shape of the resulting density function is known to be sensitive to the number and size of the bins, and the optimal binning distribution need not be of uniform sizes [18]. Characteristic features of a distribution such as bimodality may not be apparent when using bins that are too wide, while histograms can be significantly affected by random fluctuations associated with a small number of data points in bins that are too narrow. Although there is no hard and fast rule on the selection of bin sizes, the minimum number of realizations in each bin should typically range between 5 and 20 [19]. Unless stated otherwise, the histograms here are constructed such that each bin contains no fewer than ten occurrences. The noise due to the histogram construction using finite size random sample will be taken into account in the parameter estimation below.
In practice, the choice of numerical solvers for model equations determines the performance of any parameter estimation methods. For CME, there has been a tremendous development of numerical algorithms for computing the PDF solution, directly [20–22] or indirectly [15, 16, 23]. The SSA was selected in this work because this algorithm is equivalent to the CME [16, 17], motivating its use to generate in silico data. Consequently, the CME model was also solved using SSA, such that the efficacy of the proposed methods can be evaluated independently from the solvers. In this case, deficiencies of SSA will appear equally in both in silico data and the model solution.
Parameter Estimation Methods
The methods developed here are formulated as a minimization of distance measures between model predictions and experimental data. The first method makes use of the common likelihood function and the second involves a distance metric between density functions as predicted by the CME and the data. When experimental error is known or can be determined from data, this noise should be accounted for in the PDF solution. In this work, the error is assumed to be independent and identically distributed (i.i.d.) random samples from a normal distribution with zero mean and variance σ2 (N(0,σ2)), which are then added to the SSA realizations.
Maximum Likelihood (ML) Method
Density Function Distance (DFD) Method
As a reliable construction of a PDF typically requires a large number of replicates, the PDF distance may not be appropriate when only few replicates of data are available. On the other hand, the ML method above can be applied to datasets with low replicates, as it does not require the construction of a density function from the experimental data.
The binning distribution can be kept the same as the PDF, but this need not be necessarily so. Unlike PDF, the shape of CDF is less sensitive to noise from finite sampling, with the exception of the tail ends of the CDF near the minimum and maximum values of the states. An alternate formulation with a finer binning strategy gives a similar performance to the objective function above (data not shown). The lesser sensitivity to noise also makes the CDF distance method applicable to sparse datasets (low replicates), in which case the binning strategy is done based on the SSA realizations.
Global Optimization Algorithm
Aside from model solvers, the effectiveness of any parameter estimation methods also depends on the ability to find the global optima to the minimization problems. In the case of stochastic models, the error landscape is anticipated to be highly stochastic due to noise from finite experimental data points, which prevents the use of any optimization algorithms involving gradient search. Here, a variant of evolutionary algorithms, called Differential Evolution (DE), is used as a general purpose global optimization algorithm. This method can effectively handle diversified objective function planes [25], and like other evolutionary algorithms such as genetic algorithm (GA), DE starts with a random population member and looks for the global optima by generating new population members using successive recombination and mutations based on the original parent population. However, unlike GA, DE uses floating point instead of bit string encoding, and arithmetic operations instead of logical rules, thereby providing a greater flexibility in the parameter search. Among the settings of DE, the population size and total number of generations are tuned in the case studies below based on the dimensionality of the problem (i.e. number of parameters) and the choice of parameter estimation method, respectively. The remaining parameters are maintained at previously suggested values [25]. The convergence and termination of the optimization can be based on the improvement of the best objective function in the population, standard deviation of the population vector, or maximum difference between the best and worst population member. A combination of several of these criteria can provide an efficient and robust termination criterion [26]. Since the case studies considered in this work involve in silico data with known true parameters, a maximum iteration number is used as a termination criteria and the efficacy of each method is judged based on the accuracy of the respective estimates.
The SSA and DE algorithms were implemented using Message Passing Interface (MPI) in C++ and run on a Linux IBM computing cluster (CentOS; GNU C++ compiler (v4.1.1)). A combination of a long period random number generator [27] and multiple independent streams generator [28] were used to guarantee statistically independent streams of random numbers required for both the SSA and DE.
Case Study 1: RNA dynamics in E. coli
The first case study uses the CME model corresponding to the reactions and kinetic parameters proposed in the original work, as shown in Figure 1B and detailed in supplementary data [Additional File 1: Supplementary Table S1] [6]. Considering this model to be the true system, four experimental datasets of mRNA copy numbers with different replicates (m = 10, 20, 100, and 10,000) were simulated using the SSA. The simulated data were contaminated with measurement errors arising due to the normalization of the fluorescence flux, were taken to be discrete rounded values of normal random samples N(0,0.25), consistent with the actual wet-lab experiments [6]. The mRNA transcripts per cell generation were recorded every 0.5 minutes until 75 minutes, mimicking the original experimental protocol.
where l now denotes the index of the state in replicate vector after arranging the data in ascending order (i.e., o1 ≤ o2 ≤ ...≤ o m ). This construction implicitly uses the differences between sorted data values as the bin sizes. As stated earlier, since the DFD-PDF method requires the histograms of experimental data, which in the case of low replicate datasets, are highly inaccurate, this method was only performed for cell population data (m = 10,000). The DE optimization was implemented with a population size of 30 (10 × the number of parameters) for 4,000 generations and the optimization routine took about 1.5 hours for completion.
Parameter estimation of RNA dynamics model in E. coli.
k 1
k 2
k 3
k 1
k 2
k 3
k 1
k 2
k 3
0.0235 (0.0233)a
1.304 (0.3231)a
3.2201 (0.7232)a
Case Study 2: Galactose uptake model in S. cerevisiae
The CME model adapted from this work captures the random transitions among all possible promoter states as shown in Figure 3B. The states PC1, PC2 and PC3 represent free/silent, intermediate complex, and pre-initiation complex promoter configurations, respectively, while the states RC1 and RC2 describe different forms of repressed promoter configurations. The transcriptional (RNA synthesis) and translational (protein synthesis) processes are modelled as single-step irreversible reactions (Figure 3B).
In the simplified model, the different promoter configurations are assumed to be in equilibrium, which reduces the model to a set of 8 irreversible reactions, 4 states, and 8 kinetic parameters, as shown in Figure 3B (dashed boxes) [29]. As in the first case study, this model was considered to be the true system and the molecular data of yEGFP and TetR were generated using SSA, giving 104 realizations at every 5 dimensionless time units up to 50 (or about 18 times the half life of yEGFP [30]). This condition corresponds to 440 minutes of post induction by 2% galactose and 40 ng ml-1 ATc. To study the scalability of the proposed methods, the parameter estimation of the full network with 18 reactions, 9 states, and 15 kinetic parameters was also done using a second in silico dataset with 104 SSA realizations from the complete model. The details on the CME formulation for both the reduced and the complete model of the yEGFP gene expression pathway have been included in the supplementary data [Additional File 1: Supplementary Table S2 and S3].
Parameter estimation of reduced yEGFP model in S. cerevisiae
True values
κ R
κ P
γ R
γ P
Parameter estimation of full yEGFP model in S. cerevisiae.
Transcription processes
True value
k 1f
k 1b
k 2f
k 2b
k 3f
3.2 × 10-3
3.87 × 10-3
3.032 × 10-3
k 3b
Irreversible processes
κ R
κ P
γ R
γ P
for PDF and CDF, respectively, have also been evaluated, showing similar performances and observations. The outcome of the application of these criteria to the estimation of parameters in the reduced and complete yEGFP gene expression pathway is described in supplementary data [Additional File 1: Supplementary Table S4 and S5].
Case Study 3: Stochastic model of a synthetic toggle switch
A simple deterministic model was proposed to examine the behaviour of the toggle switch and to analyze different conditions of bistability [8]. The corresponding CME formulation is described in the Figure 4B and 4C[35]. Here, the propensity functions are taken directly from the deterministic model and they give effective rates of reaction following a canonical Hill equation. Taking this model to be the true system, in silico data of GFP fluorescence at IPTG concentration of 6 × 10-5 M were simulated using 104 independent SSA realizations, emulating flow cytometry data.
Parameter estimation of synthetic toggle switch in E. coli.
True value
α 1
α 2
7.331 × 10-5
5.831 × 10-4
6.0 × 10-5
In this work, three practical methods are proposed for the estimation of the parameters from (noisy) single cell datasets with low and high replicates. As the methods rely on a histogram construction of density functions from a finite sample of experimental data and Monte Carlo simulations, the objective function evaluation has a trade-off between low accuracy when using bins that are too wide, and high sensitivity to noise when bins are too small. In order to balance this trade-off, the binning was done such that the narrowest bin has at least ten occurrences. The noise associated with this binning strategy is also taken into account in the objective function in the DFD methods, which is modelled according to a binomial distribution.
The proposed methods are developed while considering a few practical issues when dealing with real biological datasets, such as data sparsity (low replicates), data noise and relatively coarse sampling intervals. The methods developed here do not require fast time-sampling like in [14], which might pose a restrictive constraint in practice. When population data are available, the DFD methods can fully exploit the additional information and rigorously handle the noise associated with the finite sample construction of a density function through the weighting factors. Although the examples considered in this work are represented by the CME, the methodologies developed in this work are generally applicable to parameter estimation of other stochastic models (e.g. Langevin), as long as the distribution density function can be constructed. Furthermore, the different methods developed in this work can be used to robustly estimate the rate constants of large scale gene expression networks as well as systems with multistability and general nonlinear propensity equations.
The case studies above showed that methods based on matching density function shapes between model and data generally performed better than maximizing likelihood function. Furthermore, the DFD-CDF distance is more sensitive to parameters than both the DFD-PDF and ML, and thus is the most effective method developed in this work. The higher sensitivity of the CDF with respect to parameter variations is expected as a result of the cumulative sum of the PDF sensitivity. This is evident from comparing the normalized objective function surfaces as shown in Figure. 2, in which the CDF objective functions have the steepest curvature. The increased curvature leads to a faster convergence to the minima in the DE optimization of the CDF than the PDF, though both methods eventually converge to optimal parameter estimates with similar accuracy. In addition, the CDF is generally less sensitive to noise from finite sampling as can be seen from the noise weighting factor S l,i when normalized with the respective probability, i.e. the coefficient of variation (CoV) . The monotonically decreasing CoV as a function F e (o l , t i ) of indicates that the CDF construction becomes less affected by finite sampling noise with increasing F e (o l , t i ).
Similar to the parameter estimation in deterministic models, parameter identifiability is a key issue in the estimation of the CME parameters. Such problem is commonly encountered in the parameter estimation of deterministic ODE models [36]. Following the same arguments from the deterministic estimation, the identifiability problem is caused by the limited information contained in the data about the parameters governing the fast transformations among the different promoter configurations. Such problem can be alleviated by getting additional measurements with a faster sampling rate and if possible, measuring the variables that are directly affected by the parameters, e.g. the fractions of promoters in each configuration of the second case study. An analogue of deterministic parameter identifiability analysis can be performed using the parametric sensitivity of the density function and experiments can be designed to maximize the degree of information in the data [35, 37, 38].
The inherent stochasticity associated with low copy number processes in the cellular genetic milieu can introduce significant noise in gene expression profiles. The modelling of such noisy system requires a careful consideration of random processes and the parameters governing the probability of random events [1]. Three parameter estimation methods for stochastic models have been proposed based on the maximum likelihood criterion and density function distances of PDF and CDF. Since state density functions of stochastic systems are often constructed from a finite number of experimental data points or Monte Carlo realizations, a careful consideration has been taken to characterize the influence of noise arising from the histogram binning. Specifically, the effects of histogram noise are directly incorporated into the parameter estimation objective function as weighting functions. Applications to two case studies have shown that the proposed methods are both effective and practical. Amongst the proposed methods, the CDF-DFD method has been found to be the most efficient in estimating the kinetic rate constant than the others (i.e., the ML and DFD-PDF methods) due to the higher sensitivity of CDF to the parameters.
This work was supported by National University of Singapore Faculty Research Council grant [R-279-000-219-112/133].
Authors' Affiliations
- McAdams HH, Arkin A: It's a noisy business! Genetic regulation at the nanomolar scale. Trends Genet 1999, 15: 65–69. 10.1016/S0168-9525(98)01659-XView ArticlePubMedGoogle Scholar
- Elowitz MB, Leibler S: A synthetic oscillatory network of transcriptional regulators. Nature 2000, 403: 335–338. 10.1038/35002125View ArticlePubMedGoogle Scholar
- Colman-Lerner A, Gordon A, Serra E, Chin T, Resnekov O, Endy D, Pesce CG, Brent R: Regulated cell-to-cell variation in a cell-fate decision system. Nature 2005, 437: 699–706. 10.1038/nature03998View ArticlePubMedGoogle Scholar
- Yang E, van Nimwegen E, Zavolan M, Rajewsky N, Schroeder M, Magnasco M, Darnell JE Jr: Decay rates of human mRNAs: correlation with functional characteristics and sequence attributes. Genome Res 2003, 13: 1863–1872. 10.1101/gr.997703View ArticlePubMedPubMed CentralGoogle Scholar
- Chou IC, Voit EO: Recent developments in parameter estimation and structure identification of biochemical and genomic systems. Math Biosci 2009, 219: 57–83. 10.1016/j.mbs.2009.03.002View ArticlePubMedPubMed CentralGoogle Scholar
- Golding I, Paulsson J, Zawilski SM, Cox EC: Real-time kinetics of gene activity in individual bacteria. Cell 2005, 123: 1025–1036. 10.1016/j.cell.2005.09.031View ArticlePubMedGoogle Scholar
- Yu J, Xiao J, Ren X, Lao K, Xie XS: Probing gene expression in live cells, one protein molecule at a time. Science 2006, 311: 1600–1603. 10.1126/science.1119623View ArticlePubMedGoogle Scholar
- Gardner TS, Cantor CR, Collins JJ: Construction of a genetic toggle switch in Escherichia coli. Nature 2000, 403: 339–342. 10.1038/35002131View ArticlePubMedGoogle Scholar
- Fange D, Elf J: Noise-induced Min phenotypes in E. coli. PLoS Comput Biol 2006, 2: e80. 10.1371/journal.pcbi.0020080View ArticlePubMedPubMed CentralGoogle Scholar
- Samoilov M, Plyasunov S, Arkin AP: Stochastic amplification and signaling in enzymatic futile cycles through noise-induced bistability with oscillations. Proc Natl Acad Sci USA 2005, 102: 2310–2315. 10.1073/pnas.0406841102View ArticlePubMedPubMed CentralGoogle Scholar
- Tian T, Xu S, Gao J, Burrage K: Simulated maximum likelihood method for estimating kinetic rates in gene expression. Bioinformatics 2007, 23: 84–91. 10.1093/bioinformatics/btl552View ArticlePubMedGoogle Scholar
- Golightly A, Wilkinson DJ: Bayesian sequential inference for stochastic kinetic biochemical network models. J Comput Biol 2006, 13: 838–851. 10.1089/cmb.2006.13.838View ArticlePubMedGoogle Scholar
- Golightly A, Wilkinson DJ: Bayesian inference for a discretely observed stochastic kinetic model. Stat Comput 2008, 125–135.Google Scholar
- Reinker S, Altman RM, Timmer J: Parameter estimation in stochastic biochemical reactions. Syst Biol (Stevenage) 2006, 153: 168–178.View ArticleGoogle Scholar
- Gillespie DT: Markov Processes: An Introduction for Physical Scientists. San Diego: Academic Press; 1991.Google Scholar
- Gillespie DT: Exact Stochastic Simulation of Coupled Chemical Reactions. J Phys Chem 1977, 81: 2340–2361. 10.1021/j100540a008View ArticleGoogle Scholar
- Gillespie DT: A rigorous derivation of the chemical master equation. Physica A 1992, 188: 404–425. 10.1016/0378-4371(92)90283-VView ArticleGoogle Scholar
- Scott DW: Multivariate Density Estimation: Theory, Practice, and Visualization (Wiley Series in Probability and Statistics). Wiley; 1992.View ArticleGoogle Scholar
- Montgomery DC, Runger GC: Applied Statistics and Probability for Engineers. New York: Wiley; 2006.Google Scholar
- Macnamara S, Bersani AM, Burrage K, Sidje RB: Stochastic chemical kinetics and the total quasi-steady-state assumption: application to the stochastic simulation algorithm and chemical master equation. J Chem Phys 2008, 129: 095105. 10.1063/1.2971036View ArticlePubMedGoogle Scholar
- Macnamara S, Burrage K, Sidje RB: Multiscale modeling of chemical kinetics via the master equation. SIAM J; Multiscale Modeling & Simulation 2008, 6: 1146–1168.View ArticleGoogle Scholar
- Munsky B, Khammash M: The finite state projection algorithm for the solution of the chemical master equation. J Chem Phys 2006, 124: 044104. 10.1063/1.2145882View ArticlePubMedGoogle Scholar
- Gibson MA, Bruck J: Efficient Exact Stochastic Simulation of Chemical Systems with Many Species and Many Channels. J Phys Chem A 2000, 104: 1876–1889. 10.1021/jp993732qView ArticleGoogle Scholar
- Kullback S, Leibler S: On Information and Sufficiency. Ann Math Stat 1951, 22: 79–86. 10.1214/aoms/1177729694View ArticleGoogle Scholar
- Storn R, Price K: Differential Evolution - A Simple and Efficient Heuristic for Global Optimization over Continuous Spaces. J Global Optim 1997, 4: 341–359. 10.1023/A:1008202821328View ArticleGoogle Scholar
- Zielinski K, Peters D, Laur R: Stopping Criteria for Single-Objective Optimization. Proceedings of the Third International Conference on Computational Intelligence, Robotics and Autonomous Systems; Singapore 2005.Google Scholar
- Matsumoto M, Nishimura T: Mersenne twister: a 623-dimensionally equidistributed uniform pseudo-random number generator. ACM Trans Model Comput Simul 1998, 8: 3–30. 10.1145/272991.272995View ArticleGoogle Scholar
- LeCuyer P, Simard R, Chen EJ, Kelton WD: An Object-Oriented Random-Number Package with many long Streams and Substreams. Oper Res 2002, 50: 1073. 10.1287/opre.50.6.1073.358View ArticleGoogle Scholar
- Blake WJ, M KA, Cantor CR, Collins JJ: Noise in eukaryotic gene expression. Nature 2003, 422: 633–637. 10.1038/nature01546View ArticlePubMedGoogle Scholar
- Chen MT, Weiss R: Artificial cell-cell communication in yeast Saccharomyces cerevisiae using signaling elements from Arabidopsis thaliana. Nat Biotechnol 2005, 23: 1551–1555. 10.1038/nbt1162View ArticlePubMedGoogle Scholar
- Arkin A, Ross J, McAdams HH: Stochastic kinetic analysis of developmental pathway bifurcation in phage lambda-infected Escherichia coli cells. Genetics 1998, 149: 1633–1648.PubMedPubMed CentralGoogle Scholar
- Ozbudak EM, Thattai M, Lim HN, Shraiman BI, Van Oudenaarden A: Multistability in the lactose utilization network of Escherichia coli. Nature 2004, 427: 737–740. 10.1038/nature02298View ArticlePubMedGoogle Scholar
- Pomerening JR, Sontag ED, Ferrell JE Jr: Building a cell cycle oscillator: hysteresis and bistability in the activation of Cdc2. Nat Cell Biol 2003, 5: 346–351. 10.1038/ncb954View ArticlePubMedGoogle Scholar
- Bhalla US, Iyengar R: Emergent properties of networks of biological signaling pathways. Science 1999, 283: 381–387. 10.1126/science.283.5400.381View ArticlePubMedGoogle Scholar
- Gunawan R, Cao Y, Petzold L, Doyle FJ: Sensitivity analysis of discrete stochastic systems. Biophys J 2005, 88: 2530–2540. 10.1529/biophysj.104.053405View ArticlePubMedPubMed CentralGoogle Scholar
- Nikerel IE, van Winden WA, Verheijen PJ, Heijnen JJ: Model reduction and a priori kinetic parameter identifiability analysis using metabolome time series for metabolic reaction networks with linlog kinetics. Metab Eng 2009, 11: 20–30. 10.1016/j.ymben.2008.07.004View ArticlePubMedGoogle Scholar
- Gadkar KG, Gunawan R, Doyle FJ: Iterative approach to model identification of biological networks. BMC Bioinformatics 2005, 6: 155. 10.1186/1471-2105-6-155View ArticlePubMedPubMed CentralGoogle Scholar
- Plyasunov S, Arkin AP: Efficient stochastic sensitivity analysis of discrete event systems. J Comp Phys 2006, 221: 724–738. 10.1016/j.jcp.2006.06.047View ArticleGoogle Scholar
- Cao Y, Gillespie DT, Petzold LR: Efficient step size selection for the tau-leaping simulation method. J Chem Phys 2006, 124: 044109. 10.1063/1.2159468View ArticlePubMedGoogle Scholar
- Chatterjee A, Vlachos DG, Katsoulakis MA: Binomial distribution based tau-leap accelerated stochastic simulation. J Chem Phys 2005, 122: 024112. 10.1063/1.1833357View ArticlePubMedGoogle Scholar
- Haseltine EL, Rawlings JB: Approximate simulation of coupled fast and slow reactions for stochastic chemical kinetics. J Chem Phys 2002, 117: 6959–6969. 10.1063/1.1505860View ArticleGoogle Scholar
- Tian T, Burrage K: Binomial leap methods for simulating stochastic chemical kinetics. J Chem Phys 2004, 121: 10356–10364. 10.1063/1.1810475View ArticlePubMedGoogle Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


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When political turmoil forces a British-Caribbean dictator to flee his island nation, he seeks refuge and hides with a rebellious teenage girl in suburban America, and ends up teaching the young teen how to start a revolution and overthrow the "mean girls" in her high school.
Idle Hands
A teenage slacker's right hand becomes possessed with murderous intent.
Josie and the Pussyc
A girl group find themselves in the middle of a conspiracy to deliver subliminal messages through popular music in this send up of the music industry and pop culture.
Knockaround Guys
The wannabe sons of mobsters go to a remote town in the Midwest, and get themselves into more trouble than anyone could anticipate.
Mars Needs Moms
A young boy named Milo gains a deeper appreciation for his mom after Martians come to Earth to take her away.
Old Dogs
Two friends and business partners find their lives turned upside down when strange circumstances lead them to be the temporary guardians of seven year-old twins.
Party Monster
Based on the true story of Michael Alig, a Club Kid party organizer whose life was sent spiraling down when he bragged on television about killing his drug dealer and roommate.
Rat Race
A Las Vegas casino magnate, determined to find a new avenue for wagering, sets up a race for money.
Scooby-Doo 2: Monste
Mystery Inc. must save Coolsville from an attack of past unmasked monsters brought to life by an evil masked figure trying to "unmask" the gang.
Sex Drive
A high school senior drives cross-country with his best friends to hook up with a babe he met online.
The Identical
During the Great Depression, identical twins are separated at birth. One, Drexel Hemsley becomes a wildly successful '50s rock star, while the other, Ryan Wade, struggles to balance his passion for music and pleasing his parents, who want him to become a preacher. Finally, Ryan rebels against his parents' wishes and launches his own music career -- performing the hits of Drexel Hemsley. Ryan later learns the truth about Drexel when their fates tragically collide.
The Italian Job
After being betrayed and left for dead in Italy, Charlie Croker and his team plan an elaborate gold heist against their former ally.
Without a Paddle
After their friend dies, three men decide to fulfill their childhood dream by going on a camping expedition for the lost D. B. Cooper bounty, with calamitous results.


text:
The Market Data Processing Unit (MPU) is a ticker plant device that facilitates large-scale, real-time data distribution. Now in its third generation, the unit employs the latest in Solarflare FPGA and Intel CPU technologies, and is utilized for a range of services including low latency and high throughput processing performance, and enterprise market data management. Institutional customers benefit from reduced hardware footprint, lower system latency, and low cost of ownership for increased business performance.
Through the MPU, ACTIV Financial continues to provide timely access to quality data from over 200 exchanges worldwide.
Key Features:
Technical Specifications
"ACTIV's world class global market data offering adds significant value to our financial ecosystem."John Knuff, GM of Global Financial Services at Equinix


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Thinking About Selling?
If you're considering selling your property, your initial questions are most likely "What is my home worth?" and "To whom should I entrust its sale?" The answer to query one requires an expert's evaluation. The answer to question number two.....the expert is Carriage House Realty.
Representing a wide range of properties and clientele in Athens and surrounding counties, Carriage House Realty is one of Athens's oldest real estate firms still in operation.
At Carriage House Realty we boast award winning agents that have been in the business for 30+ years. So, if you are considering selling your primary or vacation home, luxury estate, income property or land in or around the Athens area, you owe it to yourself and your property to contact Carriage House Realty.


text:
Monday, 04 February 2013 07:27
Israel has done it again. Last Wednesday January 30th Israeli war planes violated Lebanese air space for the nth time in their way to bomb Syrian military research center. The US and the UN had also done it again. The US supported this Israeli raid as Israel's alleged "right to protect itself", while the UN denied Israel's aggression claiming it could not verify it due to "bad weather conditions."
While Israel kept silent about the raid with some of its officials hinting that Israel could have done it and has the right to do it allegedly in self defense, pro-Zionist media sources claimed that Israeli war planes targeted trucks transporting weapons to Lebanese Hezbollah on the Syrian/Lebanese border. Media outlets, including Qatari Al Jazeera, reported Israel's fears of Hezbollah getting its hands on Syrian chemical weapons and Russian-made SA-17 anti-aircraft missiles, as reported by an Israeli security officials' chief, who spoke on condition of anonymity since he was not authorized to speak to the media.
Israel's unfounded claimed fear of having Syrian chemical weapons in the hands of Hezbollah is a total nonsense and smoke screen in the face. If Syria wanted to transport such weapons to Hezbollah it wouldn't do it in conspicuous convoys crossing the border. Hezbollah had demonstrated its capability to defeat and deter Israeli aggression using conventional weapons during summer of 2006 and does not need any chemical weapons. Such claims are used as a justification for aggressive interventions on the Syrian borders to relieve pressure on the anti-Syrian terrorist groups.
Syrian officials reported that Israeli war planes had violated Syrian air space and bombed the Jamraya research center in the suburbs of Damascus, far from the Lebanese borders. This research center has been the target of attacks by the American/Israeli-Turkey/Qatari supported anti-Syrian terrorists and militias; the so-called Free Syrian Army, al-Qaeda and Annusra Front. For the last seven months these mercenary terrorists were directed to attack Syria's air defense systems and military bases in order to incapacitate Syria's military defense capabilities. They had managed to attack one S-200 base and four surface-to-air missile bases. They have also succeeded in assassinating military scientific project managers such as Colonel Dawoud Rajiha, who was managing Syria's long-range missile project. Yet their many attempts to attack and inflict any damage onto the Jamraya research center had failed since it was heavily protected. This job was left, then, to the Israeli air forces. The Israeli air raid shows very clearly the degree of Israel's involvement with the anti-Syrian terrorist groups.
No official statement, Syrian or otherwise, had stated exactly what the Israeli planes had targeted. Yet some reports claim that the strike was intended to destroy Syria's development of advance airspace defensive technology based on nuclear plasma technology developed by Iranian born nuclear engineer Mehran Keshe, known as "Tesla of physics". It is reported that Iran gave this technology to Syria. This is the same technology Iran used to "pull" down the American spying drones in perfect conditions.
The Syrian Foreign Ministry filed a complaint letter with the United Nations Security Council urging the Council to issue a "clear condemnation of the flagrant Israeli attack on the territories of a sovereign state and the Israeli violation of the UN Charter, the international law, the Disengagement of Forces Agreement in 1974 and the relevant UNSC resolutions."
The Israeli air raid was also condemned by the Russian government calling it "unprovoked attacks on targets on the territory of a sovereign country, which blatantly violates the UN Charter and is unacceptable, no matter the motives to justify it." Iran, Syria's closest regional ally, warned that the "Zionist regime's attack on the outskirts of Damascus will have grave consequences for Tel Aviv." Iran has a cooperative defense pact with Syria, and had previously warned that any attack on Syria would be considered an act of aggression against its own country.
The Lebanese President, Michel Suleiman, denounced the Israeli raid as flagrant aggression and accused Israel of "… exploiting the development in Syria to carry out its aggressive policies, indifferent to all the humanitarian and international treaties."
Egyptian Foreign Minister, Mohamed Kamel Amr, denounced the Israeli attack saying "Such an assault on Arab land is entirely rejected and represents a flagrant violation of the United Nations Charter and international law." He, also, called on the international community to hold Israel accountable for its attacks on Arab countries, describing the raid as a danger to regional security and to Middle Eastern sovereignty.
When it comes to Israel's violations of international laws and humanitarian laws, the responses of the American-controlled United Nation are very disappointing and do not hold the international laws. Claiming "unclear weather conditions" the UN stated that it could not confirm the Israeli raid. The only thing Ban Ki-Moon, the Secretary-General of the UN, could offer was his concern over the raid. The deafening silence of the UNSC about the Israeli violations of the sovereignty of its neighboring countries had encouraged Israel to continue its terrorist attacks. The UN always apply double standards when it comes to Israel; the UN either overlooks Israeli terror attacks or considers them self-defense, while Palestinian and Lebanese opposition to Israeli occupation and terrorism is considered terrorist acts. In the case of Syria the UN overlooks the anti-Syrian terrorist supporting states of US, UK, France, Israel, Turkey, Saudi Arabia, and Qatar. These terrorist have been involved in grave human right violations and war crimes, the latest was the cold blooded execution of 80 young men in Halab.
The American response to the Israeli raid is also very typically biased towards Israel. American officials as well as media had focused on the alleged transporting Russian-made SA-17 anti-aircraft missiles to Lebanon. The NBC reported that the missiles "would remove Israel's critical freedom of flight over Lebanon." This alleged freedom of flight is a violation of the air space of a sovereign country. Would Israel give this type of freedom to Syrian war plane into Israeli air space?
Ben Rhodes, the White House deputy national security advisor, warned Syria it should not "further destabilize the region by transferring weaponry to Hezbollah." This warning implies justification for the Israeli raid and for future such raids. During an interview with French media last Friday the American Defense Secretary Panetta expressed American concern of the increasing probabilities of Hezbollah acquiring advanced weaponry from Syria. In her farewell speech, the US Secretary of State Hillary Clinton accused Russia and Iran of "stepping up" military support for Syria and thus adding fuel to possible regional conflict.
Israel is the mad dog in the Middle East attacking all its neighboring countries without any provocation. The Israelis claim that acquiring advanced weapons by any of its neighboring countries means an existential threat to Israel, and thus they consider attacking and bombing that country their right of self defense. So Israel had bombed Iraq's nuclear facility in the 1970's, waged aggression wars against Palestine, Jordan, Lebanon, Egypt and lately Gaza Strip. It had bombed in 2009 Sudanese alleged arm smuggling convoys transporting weapons to Gaza, and in 2012 bombed Sudan's small arms factory. In 2007 Israel bombed Syrian alleged nuclear facility and last week bombed Syrian research center. This twisted logic is somehow supported by the US and the UN. I wonder if this logic gives any Arab country the right to bomb Israel's nuclear facility in Dimona or any of its chemical and biological weapons facility! Does it also give them the right to bomb any American ships carrying weapons to Israel?
Israel's perpetual terrorism is a flagrant declaration of war against every country it had bombed. Israel, not Syria or any other Arab country, is the "destabilizing" factor of the Middle East. Israel's latest terrorist attack on Syria could serve as the beginning of a far wider war to include Iran, driving the whole region into an inferno, whose flame would touch the whole world.
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text:
Arsenal and Everton are both interested in the signature of Aston Villa midfielder, Fabian Delph, according to the Sunday Mirror.
Related Articles
- Manchester United & Arsenal could still land William Carvalho
- Adrien Rabiot set to make AS Roma switch
- Jack Wilshere hands Arsenal massive injury boost
Midfield reinforcements
The report claims Delph, who recently won his first England cap, is reluctant to sign a new deal at Villa which could see him leave for free next summer.
Villa's proposed offer to Delph was reportedly an improved deal to his current contract however Delph may have his sights set on a move to a higher-placed club.
Although Arsenal have numerous midfielders, Mathieu Flamini and Mikel Arteta are evidently weakening, and the need for a ball-winning midfielder has grown every season since the departure of Alex Song in 2012.
Other options
Although Wenger has a clear interest in Delph, Southampton midfielders Victor Wanyama and Morgan Schneiderlin have also caught the eye of the Gunners boss.
With the club continuously being linked with Borussia Dortmund's Sven Bender as well, Wenger has plenty of options if he chooses to strengthen in January.


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by Janae Babineaux, AmeriCorps Member on the Albemarle Foundation team at Merrydale Elementary School
1. "My favorite thing about Merrydale is the people; the teachers that fill the classrooms, the administration, the custodial staff, the cafeteria staff, my City Year team, and most importantly, the students. My students inspire me each and every day. They have taught me to be the best version of myself and to persevere. Because of them, my days are filled with learning and laughter."
-Janae Babineaux, Corps Member
2. "I love how we each bring uniqueness and character to the Merrydale team! I know I'm guaranteed to have a good laugh when I spend time with them. Basically, we're one big happy family!"
-Kimberly Ratte, Corps Member
3. "My favorite thing about Merrydale is how everyone is always making me laugh. Our team just has a genuinely good sense of humor."
-Zach Smith, Corps Member
4. "One of my favorite things about Merrydale is our special events! Last semester we celebrated Spooky Science Night, Fall Into Fun, Literacy Night, 100 Day Celebration and even got a visit from Santa!"
-Kimberly Ratte, Corps Member
5. "Morning greeting! Starting your day with lots of hugs, high-fives, and laughter is one of the greatest perks of this job!"
-Merrydale team
6. "One of my favorite things about Merrydale is our Girls on the Run team. This year Ms. Kim and I had the opportunity to coach an amazing group of girls. Girls on the Run is a national nonprofit that has created a 12-week training program that integrates being active with supporting young girls on an emotional level. The after-school program allows us to build relationships with our students and create a positive-safe environment."
-Janae Babineaux, Corps Member
7. "I love having a hand in nurturing and harvesting of the next generation ripe with promise. It's not all about core skills, though important; it's also about building life skills and strong individuals. That's why I started the chess club. It teaches strategy and critical thinking skills that can be applied to all facets of life."
-Tavidee Hoskins, Corps Member
8. "What I love about Merrydale are the people who work in the front office. Ms. Legarde has welcomed the Merrydale team since day 1, Ms. Lumar who always has our back, Ms. Boudreaux-Allen who brings passion as the first-year principal at Merrydale, and Ms. Jarvis who knows every student in the school and loves (almost) all of them."
-Tyler Wands, Team Leader
9. "Our incredible students. Here at Merrydale, our students inspire us and motivate us each and every day. We walk alongside them on the journey to success so that we may guide them, support them, and celebrate their victories!"
-Kimberly Peterson, Corps Member
10. "Our Teaching Garden allows for students to have a hand in watching plants grow. Thanks to our Team Sponsor the Albemarle Foundation, the American Heart Association and the Lemoine Company, the garden is a place where we can take our students to study content across the curriculum."
-Janae Babineaux, Corps Member
11. "My partner teacher Mrs. Bray-Range is an amazing 4th grade Science and Social Studies teacher who engages and sets high expectations for her students. She also is extremely kind, funny, and a pleasure to work with."
-Amber Curry, Corps Member
12. "I love World Culture's Club because it allows Zach and I to open up the world a little bit for our students. They learn about places far from them, cultures they otherwise might not know about, and traditions that they didn't know they loved."
-Cassidy Bowers, Corps Member
13. "Everyone has a different opinion on what happiness is and how one may pursue it and then hopefully finally achieve it. However, I bet that most people would agree that getting into a job or career that you enjoy is a crucial stepping-stone to being happy. I am one of the fortunate people that love their job. I love my job because of the people I get to work with everyday. Work is more than simply work to me because the City Year team and staff at Merrydale fill my days and thus my life with challenges, dedication, purpose, laughter and all the good things in-between. Everyone has an opinion of what happiness is and in my opinion, I found it."
-Jonathon Morris, Impact Manager


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Rowton Hall Country House Hotel, Health Club & Spa
Rowton Hall Country House Hotel, Health Club & Spa, an elegant Georgian Manor House, built in 1779. Rowton Hall is a beautiful 4AA star Country House retreat set amidst 8 acres of award winning gardens and pastureland. Located in the heart of the Cheshire countryside, just 2.5 miles from the Roman City of Chester. The hotel is ideally situated in the rural setting of Cheshire however has easy access to local Chester tourist attractions, such as the Chester race course, Chester Zoo, Blue Planet Aquarium and the historic tours of Chester to name a just a few. We have easy access to North Wales, Manchester and Liverpool whether you choose the drive or use Chester rail service. We have complimentary car parking facilities for upto 200 cars and can also accommodate for helicopters to land on the hotels grounds with ease.
This magnificent hotel is full of character and charm and is renowned for a warm, country house welcome with personal attention at all times. All 37 bedrooms are individually designed and have en suite bedrooms, direct dial telephones, trouser press, satellite TV, Tea and Coffee making facilities. We also offer complimentary Broadband in the bedrooms and wireless broadband in the conference rooms.
The Hall's reputation for first class service and excellent food is already firmly established with many customers, who return time and again to enjoy culinary magnificence and the gracious ambience of the 2AA Rosette Restaurant awarded Langdale Restaurant. Evenings can be spent in candlelit elegance, in the Oak paneled restaurant, where guests will find an endless choice of fine wines and cuisine, utilising only the freshest ingredients and home grown fruit and vegetables from the hotel's kitchen garden, which combined with tradition and excellence are the hallmarks of Rowton Hall Country House Hotel, Health Club & Spa.
As an aid to total relaxation the Health Club offers a 12 metre Indoor Swimming Pool, Whirlpool, Sauna, Steam Room, Gym, Dance Studio, Health & Beauty Treatments, Croquet Lawn and 2 Floodlit Tennis Courts.
For the total realxation break why not walk around our award winning gardens and we are delighted to annouce that the gardens are the best in Chester, this year alone we have won the Chester in Bloom award and also the North West in Bloom award.
Rowton Hall boasts three excellent function/conference/private dining rooms which all have natural light and are elegantly appointed for that special event.
Whitchurch Road
Telephone: 01244 335262
Fax: 01244 335 464
Rowton Hall is conveniently located 2.5 miles from Chester City Centre, which is one of the most central cities in the United Kingdom, we are in close proximity to North Wales, The Midlands, Manchester, Liverpool and the North West.
website http://www.rowtonhallhotel.co.uk


text:
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text:
Share some "Luck O' The Irish" with a St. Paddy's Flyer!
Go green and celebrate the luck of the Irish with friends, family or the person standing right next to you! The best events are the ones full of people looking to find the pot o' gold at the end of the rainbow, hoping to discover the rare four-leaf clover, and having a good time while doing so. So make sure your St. Paddy's Day shindig is well-attended by the happiest well-wishers. Customize a fun and cool poster on PosterMyWall, share it on your Facebook page, or hang it on display for everyone to see.
Choose from our St. Patrick's Day templates, or customize a template below.
Getting Started
Here are some things you should do to get started with your St. Patrick's Day poster right away!
- Take a tour of PosterMyWall and learn about the use of the many tools to make your desired poster a reality.
- Play around with our user-friendly tools to customize the chosen background or template.
- Stay on top of the latest deals, contests, and promotions by visiting our Facebook page.


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Hope is our emotional engine, the basis for engaging with life. It is our perception of possibilities. It is not the same as happiness or optimism. It is what we feel when we think that life is worth living. Happiness and optimism cannot exist without hope, but hope can exist without happiness or optimism. This is because we can fake optimism and pretend to be happy, but we know deep, down inside whether or not we have hope.
Believe it or not, doctors and therapists have actually said to me, my husband and children: Why do you stay together? The answer to that is because we all have hope—hope that things will improve, and life, health, and relationships will improve. And because life is ever-changing, and we have continually had hope, our lives have improved. The key is never to give up that hope and to remember if one door closes you can always hope another will open. You don't have to keep the same hopes. Shift your hope to something new.
When I first got diagnosed with an auto-immune illness, I hoped to find a cure. That was thirty years ago. Through the years, my hopes have changed, but I have never given up hope. My current hope is to live a quality life and give others hope.
When I think of hope, I am reminded of a M*A*S*H episode with Coronel Potter. A wounded soldier, Saunders, wants to kill himself and Potter pleads and prevents Saunders multiple times from taking the easy way out. Finally, Potter gives him a dose of reverse psychology by holding the gas mask over his face. Saunders fights back. His desire to live is greater than his desire to die. That's hope.
However, when we lose hope it can be hard to find motivation again. Therefore, we should continually keep it in mind each day by:
- Conducting a hope audit by thinking of all the positive things in your life.
- Reducing stress with meditation, breathing exercises, physical exercise, or relaxation techniques.
- Creating hopeful relationships with people who have a positive, hopeful attitude.
- Helping others see the best in themselves.
The most important impact we have on each other is through how we affect each other's hopes. When hope exists we give more of ourselves to what we do and so does everyone else around us. Hope is not phony and is grounded in reality with real problems such as quality of life, the development of human potential, and the wellbeing of our environment and all human living systems. Living a hopeful life is to recognize that everything and everyone matters.
Hope is energy – your positive energy, your talents, value and your soul. It is the lifeblood of the human race and needs to be treasured. Start the new year with hope and everything else will fall into place!
Cindy A. Christiansen
Sweet Romance, Humor, Suspense...and Dogs!
Fly into a good book at: http://www.dragonflyromance.com
Copyright: / 123RF Stock Photo
Excerpts about hope taken from an article at: http://www.lifehack.org/articles/lifestyle/how-to-create-a-more-hopeful-life.html


text:
The Residential flats fire action signs are from our extensive range of Health and Safety signs designed specifically for use in residential building. HMO properties (house of multiple occupancy) have strict regulations for safety and must always have a action plan in place. The Residential flats fire action signs indicates the actions that should be taken in the event of a fire in the occupants flat or other parts of the building. It also advises on what not to do in the event of discovering a fire and some preventative measures that may reduce the possibility of the fire escalating. There are instructions on telephoning the emergency services and raising the alarm by using the 'Break Glass'.
Please note we offer next day courier delivery for standard products ordered before 2pm and free courier delivery for orders over £75.
Health and safety signs regulations
The Health and Safety (Safety Signs and Signals) – Regulations 1996, requires employers to ensure that safety signs are provided (or are in place). The safety signs should be maintained in circumstances where there is a significant risk to health and safety that has not been removed or controlled by other methods.
The Regulations implement European Council Directive 92/58/EEC on minimum requirements for the provision of safety signs at work. The Directive standardises safety signs throughout member states of the European Union (EU) so that wherever a particular safety sign is seen it provides the same message. The intention is that workers moving from site to site, such as service engineers, will not be faced with different signs at different workplaces.
There are viewing distance guides available on our safety sign buying guide page. These assist in determining the appropriate size of safety signs under various light conditions.
Bespoke safety signs
We pride ourselves on having a comprehensive range of health and safety signs. However, if required, we can assist you in the design of bespoke safety signs with specific images, including those of photo quality, customised graphics, fonts, colours or wording.
If you wish the customised health and safety signs to carry your own branding, please email us at email@example.com or use the form on the 'Contact Us' page, with details of your requirements.


text:
Microsoft Corporation (Redmond, WA, USA) (2011) Method of Creating a Presentation in Real Time. US 2011/0029877 A1. (doi:US 2011/0029877 A1) (Full text available)
|PDF - Publisher pdf
Download (135kB)
An electronic display page may be displayed on an electronic display and electronic input elements may be displayed on the electronic display. If there are additional input elements, the additional electronic input elements may be accepted from an electronic input device for the electronic presentation and the additional electronic input elements may be added to the existing electronic input elements. The new electronic display page may be added to the electronic display page to create a sequence of electronic display pages, and the sequence of electronic display pages may be displayed.
|Item Type:
|Uncontrolled keywords:
|presentation, real time, electronic display page, electronic display, electronic input elements, technology, visual materials
|Q Science > QA Mathematics (inc Computing science) > QA 76 Software, computer programming,
|Faculties > Sciences > School of Computing > Computational Intelligence Group
|Depositing User:
|L. Micallef
|Date Deposited:
|21 Sep 2012 09:49 UTC
|Last Modified:
|30 Sep 2013 10:08 UTC
|Resource URI:
|https://kar.kent.ac.uk/id/eprint/30771 (The current URI for this page, for reference purposes)
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text: Samburu Intrepids is renowned as a pioneer of luxury camping in one of the world's last truly great wilderness areas. Situated on the banks of the Uaso Nyiro River in the arid heart of Samburu National Reserve, Samburu Intrepids looks out over riverbanks where herds of elephant, buffalo and zebra come daily to drink - together with the rarer 'northern species' of reticulated giraffe, Beisa oryx and long-necked gerenuk antelope. Samburu Intrepids showcases this dramatic wilderness through early morning game drives, walking safaris with skilled Samburu guides, camel safaris, and raft trips when the river allows. The camp offers just 27 luxurious tents overlooking the river. Each tent is beautifully designed with large four poster beds, classic safari furniture, and en suite bathrooms. Secluded verandas allow guests the opportunity to relax and view the wildlife while enjoying a cool drink. The open dining and lounge area create the perfect setting to relax and enjoy a meal while viewing the stunning scenery. Enjoy a plunge in the camp's swimming pool or relax with a massage at the end of the day. Services the camp offer include a boutique with souvenirs and safari essentials, email, fax, telephone, and postal service. The camp offers twice daily game drives to allow guests to view the extensive wildlife and scenery. Experience traditional dances in the Samburu village, performed by local warriors and maidens.


text:
While Loïc and Bertrand were working on Friday's presentation slides, Samuel and myself spent the whole day testing our copter's PID.
We finally found two majors bugs in our code (a motor offset unbalancing the system and a Integral term too often cleared). After that we were able for the first time to get a real flight while only acting on the thrust using remote control. We now have to add yaw PID and altitude PID and we may have something really nice to show on Friday.
Sur le même sujet :


text:
|Peter Ekberg
|RE: MSYS+MSVC for libtool branch-2-0, take 2
|Fri, 10 Jun 2005 22:57:33 +0200
Ralf Wildenhues wrote: > Hi Peter, > > I've tried your patch now, with cygwin and this version: > > | Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 13.10.3077 for 80x86 > | Copyright (C) Microsoft Corporation 1984-2002. All rights reserved. > > configured like: CC=cl CXX=cl. > > Notes: > > `link -LIB' can be a problem if the cygwin `link' (to create > hard links) > comes before the win32 paths. `LIB' works here. I have a fix for that in the attached patch, where you can override by setting MSLINK to the appropriate executable. I decided to not use LINK, since link.exe looks in the LINK veriable for extra options. Should we therefore keep track of LINK? Maybe that's an autoconf question? (The same is true for the CL and _CL_ variables used in a similar maner by cl.exe.) I have the feeling that some of this work should perhaps be in autoconf or automake, but I also have the feeling that it is not as easy to warp the arguments as needed to suit MSVC? > `LIB -EXTRACT' needs Windows paths for lib and extraction directory. > With cygwin, `cygpath -w' works. But the result needs to be properly > quoted for func_show_eval, if that is to be used. On MSYS, the paths does not need to be converted. They are automatically converted for arguments to executables outside the MSYS tree or something like that (they are assumed to be win32 executables expecting win32 paths). > After working around these, the next failure is when linking libltdl: > > | libltdl_la-ltdl.obj : error LNK2019: unresolved external > symbol _lt_libltdl_LTX_preloaded_symbols referenced in > function _lt_dlinit. > | .libs/ltdl-6.dll : fatal error LNK1120: 1 unresolved externals Haven't tried libltdl, I do not depend on it for the project I'm targeting and I have a hard time bootstrapping libtool so I haven't tried the testsuite myself. Any chance of a more up-to-date -2-0 prerelease soon, so that I can get a bootstrapped version for free? :-) > because that thing is called `_lt_ltdl_LTX_preloaded_symbols' now that > libname_spec changed. This is probably a bug in our build which > hardwires > libltdl_la_CPPFLAGS = -DLTDLOPEN=libltdl > but OTOH I'm not convinced yet that the libname_spec change > is correct. I think I have convinced myself that changing libname_spec is the right thing to do. I find that I can remove some of the really ugly stuff from the patch when I do that. > The `mv' command in this line > | + _LT_TAGVAR(archive_cmds, $1)='$CC -o $lib $libobjs > $compiler_flags `$ECHO "X$deplibs" | $Xsed -e '\''s/ > -lc$//'\''` -link -dll~linknames=~mv .libs/${libname}`$ECHO > "X${release}" | $Xsed -e +s/[.]/-/g`${versuffix}.lib > .libs/${libname}.lib' > > is also broken w.r.t lib name. I don't see what you mean here. It does what I intend it to do, it renames the import lib to not have a version number. Why is that a problem? It matches the content of the .la file. > Other than that, the HEAD convenience archive tests pass with > this. :) > Libtool's legacy test suite does too much with absolute paths which > kills my path workaround (a symlink in /tmp to my real $HOME which has > spaces in its name). > > How do I get sensible information about what's in a dll (except trying > to link against it)? (I really know little about win32.) http://www.dependencywalker.com/ (aka depends.exe) dumpbin.exe is a command line tool Things that should probably be worked on: - Install dlls in ../bin/foo.dll, just like they are for MinGW and Cygwin. The generated .la are wrong as is. - Add paths given with -L to the LIB variable so that the linker actually sees them. This should be done after converting them to win32 paths, which is easy on Cygwin and harder on MSYS. - libtool at some point thinks /mingw/bin/ld is the linker and uses that to deduce stuff, perhaps other configure checks are also a problematic, I haven't looked closely since it works for me. Attached is the latest version of the patch. Cheers, Peter (and thanks for the review)
Description: msys_msvc-3.patch
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CLEVELAND, Jan. 6, 2014 /PRNewswire/ -- As Northeastern Ohio braces for potentially record-setting low temperatures, Dominion East Ohio is reminding customers of important safety and service information as well as conservation tips during much colder weather conditions.
"As always, we want all of our customers to be safe and careful during this extremely cold weather. Customer safety, as well as the safety of our employees, is our highest priority," said Scott Miller, vice president and general manager, Dominion East Ohio. "During this extreme cold weather, Dominion East Ohio asks all customers to voluntarily turn down their thermostats and to lower the setting on their water heaters if they can do so safely, and for businesses to reduce the use of natural gas for manufacturing or processing, if practicable. These conservation efforts through this Wednesday will help keep natural gas supplies flowing to all Dominion customers."
Safety/Emergency Service: Customers should know Dominion East Ohio provides 24-hour emergency service every day. Dominion considers it an emergency if customers smell an odor of gas or if none of their natural gas appliances are working. If customers smell a natural gas odor inside a house or building, they should leave the premises immediately and call Dominion East Ohio's 24-hour emergency service from a neighbor's house, toll-free, at 1-877-542-2630. Customers should also call Dominion if they experience any service interruptions.
Conservation: With extremely cold temperatures, Dominion urges all of it customers to take prudent conservation measures, which could include temporarily reducing thermostat or water heating temperature settings. The company recommends that customers use simple conversation techniques to maintain comfort and safety such as saving energy by weather-stripping homes and insulating doors and windows. Customers also can block off drafts at the bottoms of doors with a rolled-up throw rug or towel. More conservations suggestions can be found at www.dom.com/storm-center/winter-weather-tips.jsp.
Energy Assistance: Colder weather can lead to higher natural gas bills. Dominion East Ohio strongly urges customers who believe they will not be able to maintain regular payments or service to contact the company immediately, at 1-800-362-7557 between 7 a.m. and 7 p.m. weekdays, to inquire about energy assistance programs and payment options.
Sufficient, Reliable Energy Supplies: Dominion East Ohio is served by multiple interstate pipelines and has the benefit of Ohio natural gas production and underground gas storage that will play a key role in maintaining gas deliveries to customers over the upcoming period. As with any gas utility system, there may be isolated areas where the company may experience lower operating pressures, and we are preparing to address those situations if they arise.
Dominion East Ohio is unit of Dominion, one of the nation's largest producers and transporters of energy, with a portfolio of approximately 23,500 megawatts of generation, 11,000 miles of natural gas transmission, gathering and storage pipeline and 6,400 miles of electric transmission lines. Dominion operates one of the nation's largest natural gas storage systems, with 947 billion cubic feet of storage capacity, and serves retail energy customers in 15 states. For more information about Dominion, visit the company's website at www.dom.com.
SOURCE Dominion East Ohio


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Install CM10.1 RC2 Android 4.2.2 Jelly Bean on AT&T Galaxy Note I717
The CyanogenMod team has been working hard to bring the latest version of their CM10.1 Custom Rom to masses. They have recently released the latest and in all probability the final release candidate version of the ROM; RC2. In this ROM they've added support for the AT&T Galaxy Note I717 in the RC2-build of CM10.1 Android 4.2.2 Jelly Bean ROM. This build is based on Android 4.2.2 Jelly Bean ROM and will allow you to enjoy the latest iteration of Android 4.2.2 Jelly Bean on your AT&T Galaxy Note I717.
This version of CyanogenMod brings with it all the latest customizations of CM10.1 alongside the latest Android 4.2.2 features.
Before installing this ROM, it is pertinent to mention that ROM flashing can cause your phone to brick. While, the majority of ROMs today prevent your device from getting bricked, it is still advisable to practice caution. Because it will be your responsibility in the event of your device getting bricked.
- CM 10.1 RC2-Build 4.2.2 Jelly Bean ROM For AT&T Galaxy Note I717 [File: cm-10.1.0-RC2-quincyatt.zip]
- Google Apps [File: gapps-jb-20130301-signed.zip]
Install CM10.1 RC2 Android 4.2.2 Jelly Bean on AT&T Galaxy Note I717
- Connect your AT&T Galaxy Note I717 with the PC, via USB cable.
- Download the afore mentioned CM10.1 Android 4.2.2 Jelly Bean RC2 file and copy it to the SD card of your phone.
- Disconnect your phone and switch it off. And make sure that you wait 5-6 seconds to complete the power down cycle.
- Now, you will boot the AT&T Galaxy Note I717 into recovery mode, by pressing and holding down the Volume Up button, alongside Home and the Power button, until the screen flashes, release the three buttons then. After a few seconds of that, the phone will enter recovery mode. Use the volume buttons to navigate, camera to select and the back arrow to go back.
- Once in the recovery mode, take a Nandroid backup of your existing ROM. This is necessary, to enable you to recover your current ROM install, just in case the new ROM does not perform according to your liking. In order to perform a backup, select Backup and Restore, then on the next screen, select Backup again. Go back to main recovery menu after backup is complete.
- Once done, select wipe data/factory reset, select 'Yes' on next screen to confirm your action. Wait for a few minutes until the phone wipes your data. Once complete, go back to CWM recovery menu and Wipe Cache Partition and then Wipe Dalvik Cache.
- Select install zip from sdcard, then select choose zip from sdcard. Now, locate the cm-10.1.0-RC2-quincyatt.zip file that you copied earlier in Step 2 and select it by pressing Power button. Confirm installation by selecting Yes. Install the said zip file on the next screen. The ROM installation will begin.
- Once, the phone finishes installing the ROM, you need to re-do step 7, but choose gapps-jb-20130301-signed.zip file instead of ROM zip to install the Google apps package.
- When GApps get installed, go back to the main recovery menu and select reboot system now to reboot the phone and boot up into customized Android 4.2.2 Jelly Bean ROM CM 10.1 RC2-build. The first boot will take time, so be patient!
You are now running latest CM 10.1 RC2-build Android 4.2.2 Jelly Bean ROM on AT&T Galaxy Note I717. If you are facing any issues, feel free to mention it in our comments section.


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Passage to Pluto
If Pluto's discoverer had lived to see the planet downgraded to a 'dwarf', he could have taken consolation from the fact that he will be the first person not only to have seen it but to travel through its orbit.
Discovery of a planet or celestial body must be a bittersweet experience. Unlike the Earth-bound explorers of history, space pioneers never get to visit the far-flung objects they've discovered in the seemingly endless darkness of the solar system and beyond.
However Clyde Tombaugh will come pretty close. Tombaugh first observed Pluto in 1930, when he was 24 years old and fortunate to have found work at the Lowell Observatory despite not having had the means to go to college. He died in 1997; nine years later NASA launched the New Horizons space probe bound for Pluto. On board is a sample of Clyde Tombaugh's ashes.
New Horizons is scheduled to come closest to Pluto (less than 10,000km) in July 2015 before heading past and eventually travelling out of the solar system, giving Clyde Tombaugh the most far-reaching space burial to date.
Photo credit:
Wikimedia Commons