Number Of Possible Experiments Research Articles

An experimental study on the development of self-compacting alkali-activated slag concrete mixes under ambient curing

This study was carried out to develop alkali-activated blast furnace slag concrete having self-compacting properties under ambient curing. Ground Granulated Blast Furnace Slag was used as the binder, and the blended sodium silicate liquid and sodium hydroxide pellets were added to activate the GGBFS. Fine aggregate and coarse aggregate were replaced by unprocessed blast furnace slag and electric arc furnace slag. There were a huge number of parameters, such as binder content, water-binder ratio (w/b), Na2O% and activator modulus (Ms), that influence the fresh and hardened properties of self-compacting alkali-activated Slag concrete. Taguchi’s Design of Experiments (DOE) method was used to minimize the possible number of mixes to perform experiments. Taguchi’s DOE method uses a specific design based on the orthogonal arrays to understand the entire parametric space with a less number of possible experiments. Therefore, based on Taguchi’s DOE method, detailed experiments were carried out corresponding to only nine mixes known as calibration mixes. Mix-7 shows higher compressive strength (at 28 days), modulus of elasticity, split tensile and flexural strength are 46.2 M of 46.2 MPa, 30.27 GPa, 4.43 MPa and 5.31 MPa, respectively. The results of this study show that the 28 days mechanical strength of SCAASC mixes is most controlled by Na2O% followed by binder content (GGBFS), Ms value and w/b ratio.

Micro-2D Cell Culture for cAMP Measurements Using FRET Reporters in Human iPSC-Derived Cardiomyocytes.

In the last years human induced pluripotent stem cell-derived cardiomyocytes (hIPS-CMs) have emerged as a promising alternative to rodent-derived cardiomyocytes. However, as the differentiation process is lengthy and commercially available cells are expensive, the cell number is limited. Here we provide detailed information on how to scale down 2D cell cultures of hIPS-CMs for the purpose of cAMP FRET measurements, thereby extending the number of possible experiments by more than tenfold. Crucial factors like cell density or cell number to culturing media volume can be maintained exactly as under normal culturing conditions and existing equipment does not need to be modified.The chapter covers the preparation of downscaled cell culture vessels, coating and seeding procedures, transduction or transfection of the cells with a genetically encoded cAMP FRET sensor, performing real-time cAMP FRET measurements with this sensor and the analysis of generated imaging data. Numbers for seeding areas, seeding densities, coating volumes and concentrations, media volumes, and concentrations of reagents are given as guidelines.

Case study on quality prediction of the ammunition stockpile reliability program based on a small amount of discontinuous data

This research proposes a new framework on reliability assessments of stored ammunition stocks. Many previous studies on reliability assessments are based on the correlation between the content of residual stabilizer and the year of manufacturing. However, it ignores the quality difference of the lot and other possible deterioration factors. In this research, we suggest a new framework which can overcome those shortcomings. To estimate the life of the stored ammunition, this research combined two popular techniques. The first one is Markov analysis and the second one is Bayes’ theorem. Markov analysis is used to represent the discontinuous experimental interval and quality difference in the lot, and Bayes’ theorem is used to overcome the circumstance that information from the experiments is limited. We obtained data from previous research article, and calculated three state transition matrix(function, non-function, stability) to apply the Markov analysis. Weights from the opinions of experts are given to three matrix, and the calculated total state transition matrix is used to estimate the long term ammunition status. In this paper, we propose a new framework which can reflect the quality degradation in lot and state-based business procedure. Also, the business reality that number of possible experiments is small and the observation period can be discontinuous are reflected.

Designing optimal experiments to discriminate interaction graph models.

Modern methods for the inference of cellular networks from experimental data often express nondeterminism through an ensemble of candidate models. To discriminate among these candidates new experiments need to be carried out. Theoretically, the number of possible experiments is exponential in the number of possible perturbations. In praxis, experiments are expensive and there exist several limiting constraints. Limiting factors exist on the combinations of perturbations that are technically possible, which components can be measured, and on the number of affordable experiments. Further, not all experiments are equally well suited to discriminate model candidates. The goal of optimal experiment design is to determine those experiments that discriminate most of the candidates while minimizing the costs. We present an approach for experiment planning with interaction graph models and sign consistency methods. This new approach can be used in combination with methods for network inference and consistency checking. We applied our method to study the Erythropoietin signal transduction in human kidney cells HEK293. We first used simulated experiment data from an ODE model to demonstrate in silico that our experimental design results in the inference of the gold standard model. Finally, we used the approach to plan in vivo experiments that discriminate model candidates for the Erythropoietin signal transduction in this cell line.

Infinitely Many-Armed Bandits with Budget Constraints

We study the infinitely many-armed bandit problem with budget constraints, where the number of arms can be infinite and much larger than the number of possible experiments. The player aims at maximizing his/her total expected reward under a budget constraint B for the cost of pulling arms. We introduce a weak stochastic assumption on the ratio of expected-reward to expected-cost of a newly pulled arm which characterizes its probability of being a near-optimal arm. We propose an algorithm named RCB-I to this new problem, in which the player first randomly picks K arms, whose order is sub-linear in terms of B, and then runs the algorithm for the finite-arm setting on the selected arms. Theoretical analysis shows that this simple algorithm enjoys a sub-linear regret in term of the budget B. We also provide a lower bound of any algorithm under Bernoulli setting. The regret bound of RCB-I matches the lower bound up to a logarithmic factor. We further extend this algorithm to the any-budget setting (i.e., the budget is unknown in advance) and conduct corresponding theoretical analysis.

Automation of a Nile red staining assay enables high throughput quantification of microalgal lipid production.

BackgroundWithin the context of microalgal lipid production for biofuels and bulk chemical applications, specialized higher throughput devices for small scale parallelized cultivation are expected to boost the time efficiency of phototrophic bioprocess development. However, the increasing number of possible experiments is directly coupled to the demand for lipid quantification protocols that enable reliably measuring large sets of samples within short time and that can deal with the reduced sample volume typically generated at screening scale. To meet these demands, a dye based assay was established using a liquid handling robot to provide reproducible high throughput quantification of lipids with minimized hands-on-time.ResultsLipid production was monitored using the fluorescent dye Nile red with dimethyl sulfoxide as solvent facilitating dye permeation. The staining kinetics of cells at different concentrations and physiological states were investigated to successfully down-scale the assay to 96 well microtiter plates. Gravimetric calibration against a well-established extractive protocol enabled absolute quantification of intracellular lipids improving precision from ±8 to ±2 % on average. Implementation into an automated liquid handling platform allows for measuring up to 48 samples within 6.5 h, reducing hands-on-time to a third compared to manual operation. Moreover, it was shown that automation enhances accuracy and precision compared to manual preparation. It was revealed that established protocols relying on optical density or cell number for biomass adjustion prior to staining may suffer from errors due to significant changes of the cells’ optical and physiological properties during cultivation. Alternatively, the biovolume was used as a measure for biomass concentration so that errors from morphological changes can be excluded.ConclusionsThe newly established assay proved to be applicable for absolute quantification of algal lipids avoiding limitations of currently established protocols, namely biomass adjustment and limited throughput. Automation was shown to improve data reliability, as well as experimental throughput simultaneously minimizing the needed hands-on-time to a third. Thereby, the presented protocol meets the demands for the analysis of samples generated by the upcoming generation of devices for higher throughput phototrophic cultivation and thereby contributes to boosting the time efficiency for setting up algae lipid production processes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12934-016-0433-7) contains supplementary material, which is available to authorized users.

Model of PE-CVD Apparatus: Verification and Simulations

In this paper, we present a simulation of chemical vapor deposition with metallic bipolar plates. In chemical vapor deposition, a delicate optimization between temperature, pressure and plasma power is important to obtain homogeneous deposition. The aim is to reduce the number of real-life experiments in a given CVD plasma reactor. Based on the large physical parameter space, there are a hugh number of possible experiments. A detailed study of the physical experiments in a CVD plasma reactor allows to reduce the problem to an approximate mathematical model, which is the underlying transport-reaction model. Significant regions of the CVD apparatus are approximated and physical parameters are transferred to the mathematical parameters. Such an approximation reduces the mathematical parameter space to a realistic number of numerical experiments. The numerical results are discussed with physical experiments to give a valid model for the assumed growth and we could reduce expensive physical experiments.

Validation of self-made fluorescent cyanine dyes for 2D gel-based multi-fluorescence protein analysis

Two-dimensional gel electrophoresis (2-DE) in combination with quantitative multi-fluorescence protein analysis (MFA) is the most versatile methodical tool for differential analysis of protein mixtures or even complex proteomes. It is based on covalent labelling of proteins with fluorescent cyanine dyes (Ethyl-Cy2, Propyl-Cy3 or Methyl-Cy5) before isoelectric focussing, enabling differential tagging of up to three samples which are finally separated on the same 2-D gel. To minimize costs and to increase the number of possible experiments, the cyanine dye NHS esters were synthesized in our own lab according to a protocol published by . Self-made cyanine dyes were tested by studying their labelling and fluorescent properties and possible effects on the electrophoretic mobility of labelled proteins. To validate the potential use as labels in 2-DE/MFA experiments, dyes were used for the differential analysis of the proteome of thrombin-stimulated human vascular smooth muscle cells (VSMCs).

Energetic Determinants of Oligomeric State Specificity in Coiled Coils

The coiled coil is one of the simplest and best-studied protein structural motifs, consisting of two to five helices wound around each other. Empirical rules have been established on the tendency of different core sequences to form a certain oligomeric state but the physical forces behind this specificity are unclear. In this work, we model four sequences onto the structures of dimeric, trimeric, tetrameric, and pentameric coiled coils. We first examine the ability of an effective energy function (EEF1.1) to discriminate the correct oligomeric state for a given sequence. We find that inclusion of the translational, rotational, and side-chain conformational entropy is necessary for discriminating the native structures from their misassembled counterparts. The decomposition of the effective energy into residue contributions yields theoretical values for the oligomeric propensity of different residue types at different heptad positions. We find that certain calculated residue propensities are general and consistent with existing rules. For example, leucine at d favors dimers, leucine at a favors tetramers or pentamers, and isoleucine at a favors trimers. Other residue propensities are sequence context dependent. For example, glutamine at d favors trimers in one context and pentamers in another. Charged residues at e and g positions usually destabilize higher oligomers due to higher desolvation. Nonpolar residues at these positions confer pentamer specificity when combined with certain residues at positions a and d. Specifically, the pair Leua-Alag' or the inverse was found to stabilize the pentamer. The small energy gap between the native and misfolded counterparts explains why a few mutations at the core sites are sufficient to induce a change in the oligomeric state of these peptides. A large number of possible experiments are suggested by these results.

Infrared reflectance anisotropy spectroscopy ofSi(111)−2×1: Surface excitons and polarons

The experimental data regarding the energy distribution of dangling-bond electronic states at the $\mathrm{Si}(111)\text{\ensuremath{-}}2\ifmmode\times\else\texttimes\fi{}1$ surface, with special attention to the gap between filled and empty states, are revisited. Clearly some of the results are not compatible. Theorists almost unanimously conclude in favor of a strong (about 0.25 eV) excitonic energy in the optical transitions between surface states. On the experimental side, on the other hand, conflicting results seem to support either large or negligible exciton energy. In order to reconcile all available data, it has been suggested that in highly doped samples a sizeable gap shrinking should occur. We have performed a reflectance anisotropy spectroscopy experiment in order to verify this hypothesis. The optical peak at 0.45 eV associated to dangling-bond transitions does not shift, in highly doped crystals $({N}_{\mathrm{D}}=4\ifmmode\times\else\texttimes\fi{}{10}^{18}\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3})$, within the experimental accuracy of 20 meV, thereby ruling out the hypothesis of a shrinking of the gap. Under the assumption that all experimental results are correct, an alternative explanation of this puzzling problem, based on the existence of surface polarons together with surface excitons, is suggested. Although very difficult to detect spectroscopically in a direct way, it is argued that polaronic states could play an important role in highly doped samples. A number of possible experiments to clarify the last point are suggested. Accurate theoretical calculations of the polaron energy would also be helpful.

“Beyond the fields we know...”: exploring and developing scalar timing theory

The article discusses three areas that appear neglected or underdeveloped in current treatments of scalar timing theory (SET). In particular, questions about where variance in the SET system comes from, and how memory and decision processes operate within SET are discussed. The article suggests a number of possible experiments with humans, some based on pilot work which is described, that may clarify all three areas to some degree. Methods derived from conventional studies of memory are suggested as providing techniques for investigating the operation of memory and decision processes within the SET model, both areas previously considered somewhat inaccessible. In general, the tripartite division of SET into clock, memory, and decision processes is advocated as a useful general framework for studying timing, including questions related to its neurobiological basis, whether or not data always conform to SET predictions, although more needs to be known about how all three parts of the SET system operate.

Reflections on the mechanics of granular matter

During recent years, a rather basic conflict has emerged between departments of mechanics/physics concerning the description of granular media. Experts from mechanics measure stress/strain relations, using the so-called triaxial tests, and then use these data to predict the behavior of a sample under given boundary conditions. Some physicists have a different view: they have claimed that it is not possible to define a proper displacement field in a heap of sand, and that the notion of strains is thus ambiguous. In the present text, we conclude that the crucial features are the following: (a) a heap is usually formed from a flowing phase of sand, (b) there is (empirically) a sharp interface between the flowing phase and the frozen heap below, (c) we may define for each grain a displacement, which is measured from the moment when it froze. (This displacement is due, for instance, to a compaction of the heap under its own weight.) We also present some aspects of the dynamics, including dune motions and surface flows of grains. Bouchaud, Cates and coworkers have constructed a very compact description for thin flows. We discuss the practical consequences of this picture, emphasizing some possible extensions for thicker flows. This suggests a number of possible experiments on avalanches.

Generalized MR interferography

Generalized MR interferography allows the measurement of parameters which affect the phase of the MR signal. Interference is generated by the simultaneous generation of two echoes in one excitation cycle. Local variations of the signal phase are transformed into displacement of the stripe pattern generated by interference. A number of possible experiments based on this principle are presented. The resulting interferographic images allow the fast determination of parameters such as field inhomogeneity, susceptibility, flow, and motion.

Simulation of the Krebs cycle and closely related metabolism in perfused rat liver. I. Construction of a model

The construction of an approximate computer model of the Krebs cycle and related metabolism in the perfused rat liver in terms of 35 different equations representing 34 chemical reactions is described. This model is an approximation to the biochemistry because intracellular compartmentation cannot be represented. It is used to evaluate the control and importance in vivo of enzymes, and the importance of possible control factors. Under these conditions isocitrate dehydrogenase and glutamate dehydrogenase are much less important than expected and pyruvate carboxylase much more so. Adenine nucleotides are of little importance as control factors here, pyridine nucleotides are of moderate importance, and acetyl CoA is much more important than anticipated. A number of possible experiments are suggested by the model.

Determination of optimum, transient experiments for thermal contact conductance

Some recent work indicates that the thermal contact conductance can vary significantly with time. In previous studies of transient cases, the analyses were restricted to cases utilizing either a thin specimen or thermocouples located at the interface. Because the contact conductance is a volume effect, these restrictions are frequently too severe. For this reason a method is presented for analyzing temperature data obtained from thermally thick specimens with the thermocouples not necessarily located at the interface. There are a number of possible transient experiments that might be employed, but they are not all equally as effective for determining the conductance. A criterion is given to permit comparisons between experiments; a number of possible experiments are compared utilizing this criterion. From this comparison some optimum experiments are indicated. These optimum experiments permit the contact conductance to be determined more accurately than utilizing other similar experiments with the same accuracy of the temperature measurements.