A closed-loop electrical stimulation system for cardiac cell cultures

An integrated electrical stimulation and recording system was designed for closed-loop control and analysis of cardiac cultures on planar microelectrode arrays. Stimulated action potentials from HL-1 clonal myocyte cultures were digitized, stimulation artifacts were removed using nulling and filtering methods, and analysis was performed to determine stimulation efficacy in real time. Results of this analysis were used to determine future stimulation waveform parameters such as polarity, amplitude, pulse duration, and rate or pattern. Algorithms were designed utilizing real-time analysis and control to maintain a desired electrophysiological response of the culture, such as an arbitrary capture fraction value. This paper presents the hardware and software design of the stimulus pulse circuitry, artifact extraction, analysis, and control components of the system. Applications of this technology include the study of cardiac cell physiology, improving the speed and accuracy of traditional open-loop stimulation protocols, pharmacological screening, and improving the performance of biosensors based on sensing electrical activity in cardiac cultures.     

Control Abstractions for Local Search

Comet is an object-oriented language supporting a constraint-based architecture for local search through declarative and search components. This paper proposes three novel and lightweight control abstractions for the search component, significantly enhancing the compositionality, modularity, and reuse of Comet programs. These abstractions, which includes events and checkpoints, rely on first-class closures as the enabling technology. They are especially useful for expressing, in a modular way, heuristic and meta-heuristics, unions of heterogeneous neighborhoods, and sequential composition of neighborhoods.     

Studying the XML Web: Gathering Statistics from an XML Sample

XML has emerged as the language for exchanging data on the web and has attracted considerable interest both in industry and in academia. Nevertheless, to date, little is known about the XML documents published on the web. This paper presents a comprehensive analysis of a sample of about 200,000 XML documents on the web, and is the first study of its kind. We study the distribution of XML documents across the web in several ways; moreover, we provided a detailed characterization of the structure of real XML documents. Our results provide valuable input to the design of algorithms, tools and systems that use XML in one form or another. An erratum to this article is available at .     

Report on a Suit for Libel.

Summarizes a legal experience of the American Psychological Association (APA) involving a suit for libel, in which the APA filed an Amicus Curiae brief. The APA Board of Directors directed that this experience be summarized for the information of the APA membership. The vital question before the court in this instance was whether a psychologist could examine a client at the request of a physician without the fear of being involved in litigation. The United States Court of Appeals held that the report of a psychologist in this instance was qualifiedly privileged and positively free from any actionable malice whatsoever. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Structure-aided optimization of kinase inhibitors derived from alsterpaullone

In order to perform computer-aided design of novel alsterpaullone derivatives, the vicinity of the entrance to the ATP-binding site was scanned for areas that could be useful as anchoring points for additional protein-ligand interactions. Based on the alignment of alsterpaullone in a CDK1/cyclin B homology model, substituents were attached to the 2-position of the parent scaffold to enable contacts within the identified areas. Synthesis of the designed structures revealed three derivatives (3-5) with kinase-inhibitory activity similar to alsterpaullone. The novel 2-cyanoethylalsterpaullone (7) proved to be the most potent paullone described so far, exhibiting inhibitory concentrations for CDK1/ cyclin B and GSK-3beta in the picomolar range.     

Contribution of mass spectrometry to the study of the Maillard reaction in food

The Maillard reaction or non-enzymatic browning corresponds to a set of reactions occurring between amines and carbonyl compounds, especially reducing sugars. The Maillard reaction is known to occur in heated, dried, or stored foods and in vivo in mammalian organisms. In food, the Maillard reaction is responsible for changes in colour, flavor, and nutritive value but also for the formation of stabilizing and mutagenic compounds. Because of the complexity of the Maillard reaction, mass spectrometry, coupled or not to separation techniques, is a key tool in this research area and we will review in this article the contribution of mass spectrometry to the understanding of this reaction. Different steps of Maillard reaction will be described and the importance and the role played by mass spectrometry will be highlighted. In addition, different approaches to investigate the Maillard reaction from the formation of Amadori products (early Maillard reaction product) to the flavor and melanoidin production will also be covered.     

Fractionation of surface sediment fines based on a coupled sieve-SPLITT (split flow thin cell) method

In traditional sediment grain-size separation using sieve technique, the bulk of the organic matter passes through the smallest mesh size (generally 38 microm) and is not further fractionated. In this study, a common sieve separation has therefore been coupled with an extra high capacity split flow thin cell fractionation (EHC-SPLITT) instrument to separate the bulk surface sediment not only into size-based sieve fractions (> 100, 63-100, 38-63 and < 38 microm) but particularly to further fractionate hydrodynamically the fine fraction (< 38 microm) using the EHC-SPLITT. Compared to the few previous studies using a smaller high capacity (HC) SPLITT cell, the EHC-SPLITT evaluated in detail here has several advantages (e.g., 23 times higher throughput and allowance for large particle diameters). First, the EHC-SPLITT was calibrated with particle standards. Then, its ability to fractionate fine surface sediments hydrodynamically was demonstrated with material from biogeochemically distinct regimes using two cutoff velocities (1 and 6 m d(-1)). The results from particle standards indicated a good agreement between theory and experiment and a satisfactory mass recovery for the sieve-SPLITT method (80-97%) was observed for sediment samples. The mass distributions revealed that particles < 38 microm were predominant (70-90%), indicating the large need for a technique such as the EHC-SPLITT to further fractionate the fine particles. There were clearly different compositions in the EHC-SPLITT-mediated sub-fractions of the sediment fines as indicated by analyses of organic and inorganic parameters (POC, Si, Fe and Al). The EHC-SPLITT technique has the potential to provide information of great utility to studies of benthic boundary layer transport and off-shelf export and how such processes fractionate geochemical signals.     

John C. Flanagan: Distinguished Professional Contribution Award.

Recognizes the receipt of the American Psychological Association's 1976 Distinguished Professional Contribution Award by John C. Flanagan. The award citation reads: "His many contributions to professional psychology began when he assembled the staff and directed the program of Aviation Psychology during World War II. Through ingenious test development and careful validation, this program not only made an important contribution to the combat effectiveness of the Air Corps but also demonstrated the potential of this kind of classification testing on a nationwide basis, more recently exemplified by Project TALENT. His career has been distinguished also by his founding and leadership of the American Institutes for Research. With great imagination and leadership, John C. Flanagan has made a distinguished contribution in professional psychology." A biography and a listing of the recipient's scientific writings are also included. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Distinguished Scientific Awards for an Early Career Contribution to Psychology: 1981.

The Early Career Awards, given for the first time in 1974, recognize the large number of excellent young psychologists. The awards for 1981 were given in the areas of human learning/cognition, psychopathology, and physiological psychology. Provides a citation, biography, and bibliography for the 1981 recipients: Robert J. Sternberg, Lyn Y. Abramson and Harvey J. Grill. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

James Olds: Distinguished Scientific Contribution Award.

Presents the citation and biography of James Olds on the occasion of his receiving the APA Distinguished Scientific Contribution Award for his work in the area of brain behavior relations. A bibliography of his publications is also included. (PsycINFO Database Record (c) 2010 APA, all rights reserved)