Flip the tip: an automated,high quality,cost-effective patch clamp screen

The race for creating an automated patch clamp has begun. Here, we present a novel technology to produce true gigaseals and whole cell preparations at a high rate. Suspended cells are flushed toward the tip of glass micropipettes. Seal, whole-cell break-in, and pipette/liquid handling are fully automated. Extremely stable seals and access resistance guarantee high recording quality. Data obtained from different cell types sealed inside pipettes show long-term stability, voltage clamp and seal quality, as well as block by compounds in the pM range. A flexible array of independent electrode positions minimizes consumables consumption at maximal throughput. Pulled micropipettes guarantee a proven gigaseal substrate with ultra clean and smooth surface at low cost.     

Carbon membranes from cellulose and metal loaded cellulose

The focus of this work was to find a low-cost precursor for carbon molecular sieve (CMS) membranes, and a simple way of producing them. In addition, several ways of modifying a carbon material are described. The modification method used in this study was metal doping of carbon. CMS membranes were formed by vacuum carbonization of cellulose and metal loaded cellulose. Metal additives include oxides of Ca, Mg, Fe(III) and Si, and nitrates of Ag, Cu and Fe(III).The carbon membrane containing Fe-nitrate has promising separation performance for the gas pairs O₂/N₂ and CO₂/CH₄. Carbon containing nitrates of Cu or Ag show high selectivity, but reduced O₂ and CO₂ permeability compared to carbon with Fe-nitrate. Element analysis indicates that Cu migrates to the carbon surface, creating an extra layer resistance to gas transport. A silver mirror is also seen on the surface of Ag-nitrate-containing carbon. However, the Ag- and Cu-containing membranes show a high H₂ permeability. Adding metal oxides makes the carbon membranes retard the transport of easily condensable gases (e.g. CO₂). This can be exploited for enhanced H₂/CO₂ separation efficiency.     

Characterization of crosslinked,macroporous, monosized polymer particles

Macroporous, monosized poly(meta‐divinylbenzene) and poly(para‐divinylbenzene) beads have been prepared by the two‐step activated swelling method with toluene or 2‐ethylhexanoic acid as pore‐forming agents. The type of divinylbenzene isomer as well as the type of porogen has a large effect on both physical and chemical properties of the monodisperse beads. Large pores are obtained with 2‐ethylhexanoic acid as porogen while beads prepared in the presence of toluene consist of only small pores and exhibit a shrinking behavior upon drying. The beads have considerable amounts of residual vinyl groups at the end of polymerization, as determined by bromination and Fourier transform IR analysis. The morphology and texture of the particles have been investigated by scanning electron microscopy and atomic force microscopy. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 152–169, 2000     

Amino-formaldehyde resins. Analysis by application of a mannich type reaction

The formation of Mannich bases from secondary aliphatic amines and primary alkoxymethyl compounds of urea and melamine in basic media have been studied. The rate of formation of the Mannich base is equal to the rate of decomposition of the alkoxymethyl compound. This is explained by a reaction of the amine with the Schiff base, the intermediate formed during the alkoxymethyl decomposition. In a mixture of primary alkoxymethyl and hydroxymethyl compounds of urea and melamine, the amine reacts almost selectively with the alkoxymethyl compound. An analytical method for the determination of primary dimethylene ether groups of primary alkoxymethyl groups in mixture with hydroxymethyl groups is developed.     

Uncertainty and sensitivity analyses as a validation tool for BWR bundle thermal-hydraulic predictions

In recent years, more realistic safety analyses of nuclear reactors have been based on best estimate (BE) computer codes. The need to validate and refine BE codes that are used in the predictions of relevant reactor safety parameters, led to the organization of international benchmarks based on high quality experimental data. The OECD/NRC BWR full-size fine-mesh bundle test (BFBT) benchmark offers a good opportunity to assess the accuracy of thermal-hydraulic codes in predicting, among other parameters, single and two phase bundle pressure drop, cross-sectional averaged void fraction distributions and critical powers under a wide range of system conditions. The BFBT is based on a multi-rod assembly integral test facility which is able to simulate the high pressure, high temperature fluid conditions found in BWRs through electrically heated rod bundles. Since code accuracy is unavoidably affected by models and experimental uncertainties, an uncertainty analysis is fundamental in order to have a complete validation study. In this paper, statistical uncertainty and sensitivity analyses are used to validate the thermal-hydraulic features of the POLCA-T code, based on a one dimensional model of the following macroscopic BFBT exercises: (1) single and two phase bundle pressure drop, (2) steady-state cross-sectional averaged void fraction, (3) transient cross-sectional averaged void fraction and (4) steady-state critical power tests. The Latin hypercube sampling (LHS) strategy was chosen since it densely stratifies across the range of each uncertain input probability distribution, allowing a much better coverage of the input uncertainties than simple random sampling (SRS). The results show that POLCA-T predictions on pressure drop and void fractions under a wide range of conditions are within the validation limits imposed by the uncertainty analysis, while the accuracy of critical power predictions depends much on the boundary and input conditions.     

Contingency detection and the contingent organization of behavior in interactions: Implications for socioemotional development in infancy.

In this report, the authors review studies addressing the issue of contingencies in social and nonsocial contexts during infancy. The review is divided into 4 groups of studies that suggest that (a) young infants detect contingencies unrelated to their behavior; (b) infants detect contingencies involving their behavior; (c) the study of contingency is pertinent for addressing behavioral organization within parent-infant interaction; and (d) there is a link between behavioral contingency in early infancy and global measures of socioemotional development that are predictive of social functioning at later points during childhood. Throughout the report, the pertinence of infant emotional responses during contingency-related tasks is emphasized. Finally, the authors delineate certain enduring questions regarding contingency experience in infancy and suggest ways of organizing research to address some of them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Amino Starches as pH‐Sensitive Coatings: Synthesis and Application

The aim of this work was to carry out a systematic investigation of the preparation conditions of starch materials with pH‐dependent solubility. Furthermore, appropriate conditions for application of those materials as surface coatings should be established. Thus, samples of starch derivatives with tertiary amino substituents were synthesised and characterised by ¹H‐NMR spectroscopy and pH‐turbidimetry. Variation of both kind and molar mass of the used starch substrate and the nature and degree of substitution of the amino component led to two materials containing diisopropylamino groups with the desired properties in a single‐ or two‐component coating. Using a commercial fluidised‐bed coating procedure spherules of a waxy surfactant were coated with different modified starches. The stabilities of the shells were examined under dishwasher‐like conditions and monitored by tensiometry.     

On Sequenial Tests of the Bincknial Distribution

In this paper, we consider the detailed characteristics of the standard sequential test of a simple hypothesis versus a single alternative for the case of the binomial distribution. A method is developed which permits evaluation of the associated probabilities of acceptance and/or rejection of the null hypothesis at each stage. From this information, the quantitative features of the test (Operating Characteristic and test termination probability) are completely determined. Curves are presented to facilitate assessment of the sequential procedure in practical cases. A sequential test is compared with a fixed sample size test having approximately the same Operating Characteristic. Wald's approximation for the average sample number is compared with exact values.     

Detection and Localization of Delaminations in Thin Carbon Fiber Reinforced Composites with the Ultrasonic Polar Scan

In this paper, the hybrid compliance-stiffness matrix method for simulating wave propagation in (delaminated) multilayered media with viscoelastic anisotropy has been confronted with high-quality amplitude and phase experiments on delaminated composites, obtained using the ultrasonic polar scan setup (UPS) in transmission by considering harmonic as well as pulsed ultrasound. Results are presented for multiple thin carbon/epoxy laminates with an artificial edge delamination induced by a foil insert, showing a good agreement between experimental recording and numerical modeling. The obtained results further reveal the feasibility of the harmonic UPS to detect and even locate the depth-position of multiple delaminations in fiber reinforced composites. Considering that the harmonic UPS method does not rely on the detection of different echoes like the classical C-scan, but rather expounds the conditions for efficient stimulation of guided waves in the solid, the method is found to be highly suited for inspecting thin composite materials for the presence of delaminations.