Development of a high performance parallel computing platform and its use in the study of nanostructures : clusters, sheets and tubes .

Small clusters of gallium oxide, technologically important high temperature ceramic, together with interaction of nucleic acid bases with graphene and small-diameter carbon nanotube are focus of first principles calculations in this work. A high performance parallel computing platform is also developed to perform these calculations at Michigan Tech. First principles calculations are based on density functional theory employing either local density or gradient-corrected approximation together with plane wave and gaussian basis sets. The bulk Ga2O3 is known to be a very good candidate for fabricating electronic devices that operate at high temperatures. To explore the properties of Ga2O3 at nonoscale, we have performed a systematic theoretical study on the small polyatomic gallium oxide clusters. The calculated results find that all lowest energy isomers of GamOn clusters are dominated by the Ga-O bonds over the metal-metal or the oxygen-oxygen bonds. Analysis of atomic charges suggest the clusters to be highly ionic similar to the case of bulk Ga2O3. In the study of sequential oxidation of these slusters starting from Ga2O, it is found that the most stable isomers display up to four different backbones of constituent atoms. Furthermore, the predicted configuration of the ground state of Ga2O is recently confirmed by the experimental result of Neumark's group. Guided by the results of calculations the study of gallium oxide clusters, performance related challenge of computational simulations, of producing high performance computers/platforms, has been addressed. Several engineering aspects were thoroughly studied during the design, development and implementation of the high performance parallel computing platform, rama, at Michigan Tech. In an attempt to stay true to the principles of Beowulf revolutioni, the rama cluster was extensively customized to make it easy to understand, and use - for administrators as well as end-users. Following the results of benchmark calculations and to keep up with the complexity of systems under study, rama has been expanded to a total of sixty four processors. Interest in the non-covalent intereaction of DNA with carbon nanotubes has steadily increased during past several years. This hybrid system, at the junction of the biological regime and the nanomaterials world, possesses features which make it very attractive for a wide range of applicatioins. Using the in-house computational power available, we have studied details of the interaction between nucleic acid bases with graphene sheet as well as high-curvature small-diameter carbon nanotube. The calculated trend in the binding energies strongly suggests that the polarizability of the base molecules determines the interaction strength of the nucleic acid bases with graphene. When comparing the results obtained here for physisorption on the small diameter nanotube considered with those from the study on graphene, it is observed that the interaction strength of nucleic acid bases is smaller for the tube. Thus, these results show that the effect of introducing curvature is to reduce the binding energy. The binding energies for the two extreme cases of negligible curvature (i.e. flat graphene sheet) and of very high curvature (i.e. small diameter nanotube) may be considered as upper and lower bounds. This finding represents an important step towards a better understanding of experimentally observed sequence-dependent interaction of DNA with Carbon nanotubes.

Development of a wireless platform to generate nitric oxide for implanted biomedical devices

The perturbation of homeostatic mechanisms caused by interactions between any indwelling biomedical device and the biological medium into which it is implanted initiates a dynamic wound healing response from the host which can be rigorous and ongoing. The typical result of this response is a severe degradation in the performance and safety of the device, often to the extent of precluding their clinical use. Nitric oxide (NO) is an endogenously produced biomolecule capable of mediating many of the cellular processes leveraged against implanted devices. The in vivo performance of indwelling devices prepared with NO release coatings has recently been evaluated with very encouraging results. This work developed a platform capable of both generating programmable fluxes of NO and directly evaluating the performance of indwelling probes under different profiles of NO generation. This platform can be used to improve the efficacy of NO release materials in mitigating the host response.

CHARACTERIZATION OF ELECTRODEPOSITED POLYANILINE BIOSENSOR PLATFORM FOR ESCHERICHIA COLI O157:H7 DETECTION

Amperometric electrodeposition has been used to obtain uniform, conductive, and repeatable polyaniline (PANi) thin films for use in nano scaled biochemical sensors. This report describes the characterization of these films. Techniques such as ellipsometry were used to test repeatability of the deposition and the uniformity of the deposited thin films. Raman spectroscopy was utilized to confirm the composition of the deposited PANi thin films. Fluorescence microscopy was used to determine the immobilization of antibodies to the PANi thin films using biotin-avidin interactions, as well as the density of active binding sites. Ellipsometry results demonstrated that biomolecules could be immobilized on PANi films as thin as 9nm. Evidence from the Raman spectroscopy demonstrated the conductive nature of the PANi films. The fluorescence microscopy demonstrated that antibodies could be immobilized on PANi films, although the experiment also demonstrated a low density of binding sites. The characterization demonstrates the utility of the PANi thin films as a conductive interface between the inorganic sensor platform and biochemical molecules.

Pharmacovigilance of drug allergy and hypersensitivity using the ENDA-DAHD database and the GALEN platform. The Galenda project

Nonallergic hypersensitivity and allergic reactions are part of the many different types of adverse drug reactions (ADRs). Databases exist for the collection of ADRs. Spontaneous reporting makes up the core data-generating system of pharmacovigilance, but there is a large under-estimation of allergy/hypersensitivity drug reactions. A specific database is therefore required for drug allergy and hypersensitivity using standard operating procedures (SOPs), as the diagnosis of drug allergy/hypersensitivity is difficult and current pharmacovigilance algorithms are insufficient. Although difficult, the diagnosis of drug allergy/hypersensitivity has been standardized by the European Network for Drug Allergy (ENDA) under the aegis of the European Academy of Allergology and Clinical Immunology and SOPs have been published. Based on ENDA and Global Allergy and Asthma European Network (GA(2)LEN, EU Framework Programme 6) SOPs, a Drug Allergy and Hypersensitivity Database (DAHD((R))) has been established under FileMaker((R)) Pro 9. It is already available online in many different languages and can be accessed using a personal login. GA(2)LEN is a European network of 27 partners (16 countries) and 59 collaborating centres (26 countries), which can coordinate and implement the DAHD across Europe. The GA(2)LEN-ENDA-DAHD platform interacting with a pharmacovigilance network appears to be of great interest for the reporting of allergy/hypersensitivity ADRs in conjunction with other pharmacovigilance instruments.

A Communication Platform for Tele-monitoring and Tele-management of Type 1 Diabetes

Type 1 diabetes mellitus is a chronic disease characterized by blood glucose levels out of normal range due to inability of insulin production. This dysfunction leads to many short- and long-term complications. In this paper, a system for tele-monitoring and tele-management of Type 1 diabetes patients is proposed, aiming at reducing the risk of diabetes complications and improving quality of life. The system integrates Wireless Personal Area Networks (WPAN), mobile infrastructure, and Internet technology along with commercially available and novel glucose measurement devices, advanced modeling techniques, and tools for the intelligent processing of the available diabetes patients information. The integration of the above technologies enables intensive monitoring of blood glucose levels, treatment optimisation, continuous medical care, and improvement of quality of life for Type 1 diabetes patients, without restrictions in everyday life activities.

Potentiometric platform for the quantification of cellular potassium efflux

Renewed interest in the measurement of cellular K(+) effluxes has been prompted by the observation that potassium plays an active and important role in numerous key cellular events, in particular cell necrosis and apoptosis. Although necrosis and apoptosis follow different pathways, both induce intracellular potassium effluxes. Here, we report the use of potassium-selective microelectrodes located in a microfluidic platform for cell culture to monitor and quantify such effluxes in real time. Using this platform, we observed and measured the early signs of cell lysis induced by a modification of the extracellular osmolarity. Furthermore, we were able to quantify the number of dying cells by evaluating the extracellular potassium concentration. A comparison between the potentiometric measurement with a fluorescent live-dead assay performed under similar conditions revealed the delay between potassium effluxes and cell necrosis. These results suggest that such platforms may be exploited for applications, such as cytotoxicological screening assays or tumor cell proliferation assays, by using extracellular K(+) as cell death marker.

Development of a multifunctional platform for extra- and intracellular ionic activities recording

We present the development of a multifunctional platform equipped with an array of silicon nitride micropipettes with dimensions allowing the implementation of extra- and intracellular operations. Micropipettes with outer diameter that ranges from 6 mum down to 300 nm and with walls thicknesses of 500 down to 150 nm are presented. The generic technology developed to fabricate these micropipettes has a number of advantages, including the ability to be implemented as ion-selective electrodes for (A) intracellular and (B) extracellular recordings and as (C) local drug microdispensers.

TV Signal Delivery to Cable Operators and DTH Platform Operators

The paper discusses new business models of transmission of television programs in the context of definitions of broadcasting and retransmission. Typically the whole process of supplying content to the end user has two stages: a media service provider supplies a signal assigned to a given TV channel to the cable operators and satellite DTH platform operators (dedicated transmission), and cable operators and satellite DTH platform operators transmit this signal to end users. In each stage the signals are encoded and are not available for the general public without the intervention of cable/platform operators. The services relating to the supply and transmission of the content are operated by different business entities: each earns money separately and each uses the content protected by copyright. We should determine how to define the actions of the entity supplying the signal with the TV program directly to the cable/digital platform operator and the actions of the entity providing the end user with the signal. The author criticizes the approach presented in the Chellomedia and Norma rulings, arguing that they lead to a significant level of legal uncertainty, and poses the basic questions concerning the notion of “public” in copyright.

Entwicklung eines Konzepts zum Lagermanagement mit Optimierungsansätzen auf Ebene eines neuen Regalbediengerätes

Die Grundidee hinter dem neuen Regalbediengerät ist die Minimierung der zu bewegenden Last durch die Verwendung einer seilbasierten Stewart-Gough-Plattform (SGP). Das klassische Regalbediengerät (RBG) wird dabei durch eine Plattform ersetzt, die an bis zu acht vorgespannten Seilen befestigt ist. Unterstützt wird diese Bauform durch eine abgestimmte Steuerungssoftware, die es ermöglicht die Vorteile des RBG optimal zu nutzen. Das hier mit Software vorgestellte Konzept regelt die Vorgehensweise zur Optimierung von Ein- und Auslagerungsaufträgen in einem Lagerregal, sowie die Optimierung der Fachbelegung in Zeiten ohne direkten Auftrag. Es beinhaltet dabei Mechanismen, die bestimmen wann Aufträge abgearbeitet werden, in welcher Reihenfolge und in welchen Kombinationen. Ziel ist es Ein- und Auslagerungsaufträge so zu kombinieren, dass möglichst effizient und schnell gearbeitet wird.

A Fast Platform for Interactive E-Learning Systems

Modern e-learning systems represent a special type of web information systems. By definition, information systems are special computerized systems used to perform data operations by multiple users simultaneously. Each active user consumes an amount of hardware resources. A shortage of hardware resources can be caused by growing number of simultaneous users. Such situation can result in overall malfunctioning or slowed-down system. In order to avoid this problem, the underlying hardware system gets usually continuously upgraded. These upgrades, typically accompanied with various software updates, usually result in a temporarily increased amount of available resources. This work deals with the problem in a different way by proposing an implementation of a web e-learning system with a modified software architecture reducing resource usage of the server part to the bare minimum. In order to implement a full-scale e-learning system that could be used as a substitute to a conventional web e-learning system, a Rich Internet Application framework was used as basis. The technology allowed implementation of advanced interactivity features and provided an easy transfer of a substantial part of the application logic from server to clients. In combination with a special server application, the server part of the new system is able to run with a reasonable performance on a hardware with very limited computing resources.

Influence of platform switching on bone-level alterations: a three-year randomized clinical trial

The concept of platform switching has been introduced to implant dentistry based on clinical observations of reduced peri-implant crestal bone loss. However, published data are controversial, and most studies are limited to 12 months. The aim of the present randomized clinical trial was to test the hypothesis that platform switching has a positive impact on crestal bone-level changes after 3 years. Two implants with a diameter of 4 mm were inserted crestally in the posterior mandible of 25 patients. The intraindividual allocation of platform switching (3.3-mm platform) and the standard implant (4-mm platform) was randomized. After 3 months of submerged healing, single-tooth crowns were cemented. Patients were followed up at short intervals for monitoring of healing and oral hygiene. Statistical analysis for the influence of time and platform type on bone levels employed the Brunner-Langer model. At 3 years, the mean radiographic peri-implant bone loss was 0.69 ± 0.43 mm (platform switching) and 0.74 ± 0.57 mm (standard platform). The mean intraindividual difference was 0.05 ± 0.58 mm (95% confidence interval: -0.19, 0.29). Crestal bone-level alteration depended on time (p < .001) but not on platform type (p = .363). The present randomized clinical trial could not confirm the hypothesis of a reduced peri-implant crestal bone loss, when implants had been restored according to the concept of platform switching.