A dry process for production of microfluidic devices based on the lamination of laser-printed polyester films

A new microfabrication process based on a xerographic process is described. A laser printer is used to selectively deposit toner on a polyester film, which is subsequently laminated against another polyester film. The toner layer binds the two polyester films and allows the blank regions to become channels for microfluidics. These software-outlined channels are approximately 6 microm deep. Approximately twice this depth is obtained by laminating two printed films. The resulting devices were not significantly damaged after 24 h of exposure to aqueous solutions of H3PO4, NaOH, methanol, acetonitrile, or sodium dodecyl sulfate. Electric tests with an impedance analyzer and microchannels filled with KCl solution demonstrated that (1) wide channels suffer from deformation of the top and bottom walls due to the lamination of the polyester films and (2) the toner walls are somewhat porous. Although these drawbacks limit the maximum width of a channel and the minimum distance between two channels, the process is an attractive option to other expensive, laborious, and time-consuming methods for microchannels fabrication. The process has been used to implement devices for electrospray tip and capillary electrophoresis with contactless conductivity detection.     

Intranucleolar localization of DNA topoisomerase IIalpha is a distinctive feature of necrotic, but not of apoptotic, Jurkat T-cells

Two distinct types of cell death have been described: apoptosis and necrosis. However, it is becoming increasingly clear that the differences between these two types are far less numerous than initially thought. Morphological analyses might provide important information to distinguish apoptotic from necrotic samples. We recently reported that in necrotic, but not apoptotic, HL-60 human myeloid leukaemia cells, the nuclear protein topoisomerase IIalpha concentrated in nucleoli. In order to ascertain whether or not this phenomenon was restricted to a peculiar cell type or could be detected also in cells of lymphoid lineage, we performed an investigation aimed at defining the localization of topoisomerase IIalpha in apoptotic and necrotic Jurkat human T lymphoblastoid cells. Immunofluorescence staining demonstrated that topoisomerase IIalpha was excluded from the condensed chromatin of apoptotic cells, whereas in necrotic cells it was localized in discrete nuclear dots. Immuno-electron microscopy analysis showed that topoisomerase IIalpha was undetectable in nucleoli of normal and apoptotic cells, whereas it was present in the nucleolus of necrotic cells irrespectively of the type of inducer used (ethanol, H(2)O(2), HgCl(2)). Taken together, our findings identify topoisomerase IIalpha as a potential morphological marker useful to discriminate between apoptotic and necrotic cells.     

Employing virtual humans for education and training in X3D/VRML worlds

Web-based education and training provides a new paradigm for imparting knowledge; students can access the learning material anytime by operating remotely from any location. Web3D open standards, such as X3D and VRML, support Web-based delivery of Educational Virtual Environments (EVEs). EVEs have a great potential for learning and training purposes, by allowing one to circumvent physical, safety, and cost constraints. Unfortunately, EVEs often leave to the user the onus of taking the initiative both in exploring the environment and interacting with its parts. A possible solution to this problem is the exploitation of virtual humans acting as informal coaches or more formal instructors. For example, virtual humans can be employed to show and explain maintenance procedures, allowing learners to receive more practical explanations which are easier to understand. However, virtual humans are rarely used in Web3D EVEs, since the programming effort to develop and re-use them in different environments can be considerable. In this paper, we present a general architecture that allows content creators to easily integrate virtual humans into Web3D EVEs. To test the generality of our solution, we present two practical examples showing how the proposed architecture has been used in different educational contexts.     

Postfailure Mechanics of Landslides: Laboratory Investigation of Flowslides in Pyroclastic Soils

Of all landslides, subaerial flowslides are the most dangerous. According to the literature, flowslides in saturated granular deposits are caused by static liquefaction induced by loss of stability. However, the catastrophic flowslides that occurred on steep slopes in Campania (southern Italy) in 1998, 1999, and 2005 were triggered by rainwater infiltration into shallow deposits of pyroclastic soils, which were initially unsaturated. Starting from the experience collected during the investigations of some of these landslides, the writers consider flowslide evolution as a result of a mechanical chain process characterized by saturation increase due to rainwater infiltration, mechanical degradation, volumetric collapse, and static liquefaction, culminating in complete fluidization of the soil. In the paper this chain process is investigated through wetting tests both in suction controlled triaxial apparatuses and in a well-equipped small scale slope model.     

Knowledge-Assisted Retrieval of Online Product Information in Architectural/Engineering/Construction

With a better understanding about the product market, industry practitioners can make more informed decisions for product specification, selection, and procurement. However, current approaches that support Architectural/Engineering/Construction (A/E/C) information acquisition do not provide a comprehensive market scan. While the Internet provides an ever-growing resource for product information, existing approaches have limited capabilities to make use of this virtual market. Therefore, the writers have developed a knowledge-assisted approach to specifically address the potential of the virtual market—help retrieve A/E/C product information, particularly information about different manufacturers, from the Internet. The paper introduces the building blocks of the developed approach, which includes domain knowledge utilization, information retrieval (IR) techniques, and strategies that incorporate domain knowledge into knowledge-supported IR approaches. Specifically, domain knowledge represented in the form of a thesaurus was used with query expansion strategies under the framework of an adaptation of the extended IR Boolean model. It was concluded from the prototype validation that domain knowledge can be extremely helpful when acquiring A/E/C product information from online resources using the developed approach.     

Differential ionisation measurements for positron impact

An overview of methods being used at the University of Missouri-Rolla to measure differential ionisation for positron impact is presented. Examples of triply differential electron emission and doubly differential positron scattering and energy loss data are given and contributions to each due to binary and recoil events are discussed. In addition, angular distribution data for electron emission due to double and triple ionisation are presented.     

A MATHEMATICAL MODEL FOR PARALLEL FLOW DRYER FOR SLABS WITH HIGH THERMAL DIFFUSIVITY

An analytical model for the process is developed. The thermal diffusivity of the drying slabs is assumed infinite and the moisture diffusivity constant during the entire drying process.

With specified initial and boundary conditions, the mathematical model yields a two-part solution for the diffusion equation. The first part is valid for the initial drying during which the surface moisture content exceeds the value of fiber saturation. This part of the solution is used until the surface moisture content drops to the fiber saturation value. The moisture profile at the end of this period is used as the initial condition for the second period of drying which takes place under hygroscopic conditions.

Two simplifying assumptions are adapted for the hygroscopic region: 1. The dependence between the surface temperature and the moisture content is linear. 2. Constant (average) absorption heat is used during this second drying period.

For both parts of the solution, the surface moisture gradient is proportional to the local temperature difference between the drying air and the slab surface. This temperature difference can be expressed by means of a water mass balance equation for the part of the dryer between the slab in-feed and the point considered and by using the thermodynamic properties of the humid air.     

Direct torque control as variable structure control: Existence conditions verification and analysis

The aim of this paper is to propose a formal approach to derive direct torque control (DTC). Using the theory of variable structure control (VSC) and in particular the sliding mode approach, a detailed analysis of the possible operating regions for both induction and brushless machines are described. This analysis allows to clarify the consequences of a specific switching table in terms of control stability. In particular, DTC is presented and analysed as a special case of sliding mode strategy. Sliding mode existence conditions are verified and the most critical operating regions are obtained. The proposed formal analysis allows to define more sophisticated switching tables which assure stable operation.     

Plug-In Hybrid Electric Vehicle: Modeling, Prototype Realization, and Inverter Losses Reduction Analysis

Nowadays, the greatest part of the effort to reduce pollution emissions is directed toward the hybridization of automotive drive trains. In particular, the design of hybrid vehicles requires a complete system analysis, including the optimization of the electric and electronic devices installed on the vehicle and the design of all the mechanical connections between the different power sources to reach the required performances. The aim of this paper is to describe the design and prototype realization of a plug-in hybrid electrical vehicle (PHEV). Specifically, an energetic model was developed in order to analyze and optimize the power flux between the different parts. This model was experimentally validated using a prototype PHEV. In addition, in order to improve the driving range in an all-electric model (all-electric range), a detailed analysis of the inverter control was performed, because this component is one of the key components of the power train. In order to reduce inverter losses and dimensions, several control methods can be adopted. In this paper, a direct self-control strategy for reducing the inverter losses is presented and validated.      

An application of kernel methods to gene cluster temporal meta-analysis

The application of various clustering techniques for large-scale gene-expression measurement experiments is a well-established method in bioinformatics. Clustering is also usually accompanied by functional characterization of gene sets by assessing statistical enrichments of structured vocabularies, such as the gene ontology (GO) [Gene Ontology Consortium. The gene ontology (GO) project in 2006. Nucleic Acids Research (Database issue), vol. 34; 2006. p. D322–6]. If different clusters are generated for correlated experiments, a machine learning step termed cluster meta-analysis may be performed, in order to discover relations among the components of such sets. Several approaches have been proposed: in particular, kernel methods may be used to exploit the graphical structure of typical ontologies such as GO. Following up the formulation of such approach [Merico D, Zoppis I, Antoniotti M, Mauri G. Evaluating graph kernel methods for relation discovery in GO-annotated clusters. In: KES-2007/WIRN-2007, Part IV, Lecture notes in artificial intelligence, vol. 4694. Berlin: Springer; 2007. p. 892–900; Zoppis I, Merico D, Antoniotti M, Mishra B, Mauri G. Discovering relations among GO-annotated clusters by graph kernel methods. In: Proceedings of the 2007 international symposium on bioinformatics research and applications. Lecture notes in computer science, vol. 4463. Berlin: Springer; 2007], in this paper we discuss, from an information-theoretic point of view, further results about its applicability and its performance.