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OPTIMAL CONFIGURATION FOR NODES IN MIXED CELLULAR AND MOBILE AD HOC NETWORK FOR INETBabalola, Olusola 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / As part of Morgan’s iNET development, the Mixed Cellular and Mobile Ad hoc Network (MCMN) architecture has been 1proposed to provide coverage to over-the horizon test articles. Nodes in MCMN are assigned to one of three possible modes- Ad hoc, Cellular or Gateway. We present architecture for the proposed MCMN and some performance analysis to characterize the network. The problem of organizing nodes in this mixed network with optimal configuration is significant. This configuration gives nodes ability to know the best mode to operate and communicate with other nodes. Node organization is critical to the performance of the mixed network and to improve communication. The configuration of nodes required to optimally organize nodes in MCMN is demonstrated. The problem of evaluating configuration parameters for nodes in a mixed network is a nonlinear and complex one. This is due to the various components like the number of nodes, geographical location, signal strength, mobility, connectivity and others that are involved. Clustering techniques and algorithms have been used in literature to partition networks into clusters to support routing and network management. A clustering technique is employed to dynamically partition the aggregate network into Cluster Cells (CCs). A gateway node is selected for each CC which relays traffic from the cellular to the Ad hoc and vice versa. A trade-off analysis of the cellular boundary is presented using the maximum of the minimum data rate in the network. Numerical analysis and experiments are provided to show that the coverage can be extended to test articles in over-the-horizon region. It is also shown that, when the network is well organized, performance is improved.
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Microbiology of diabetic foot infections: from Louis Pasteur to 'crime scene investigation'Spichler, Anne, Hurwitz, Bonnie L., Armstrong, David G., Lipsky, Benjamin A. January 2015 (has links)
Were he alive today, would Louis Pasteur still champion culture methods he pioneered over 150 years ago for identifying bacterial pathogens? Or, might he suggest that new molecular techniques may prove a better way forward for quickly detecting the true microbial diversity of wounds? As modern clinicians faced with treating complex patients with diabetic foot infections (DFI), should we still request venerated and familiar culture and sensitivity methods, or is it time to ask for newer molecular tests, such as 16S rRNA gene sequencing? Or, are molecular techniques as yet too experimental, non-specific and expensive for current clinical use? While molecular techniques help us to identify more microorganisms from a DFI, can they tell us ‘who done it?', that is, which are the causative pathogens and which are merely colonizers? Furthermore, can molecular techniques provide clinically relevant, rapid information on the virulence of wound isolates and their antibiotic sensitivities? We herein review current knowledge on the microbiology of DFI, from standard culture methods to the current era of rapid and comprehensive ‘crime scene investigation' (CSI) techniques.
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High-throughput intracellular delivery of proteins and plasmidsPark, Seonhee 27 May 2016 (has links)
Intracellular delivery of macromolecules is crucial for the success of many research and clinical applications. Several conventional intracellular delivery methods have been used for many years but are still inadequate for several applications because of the issues associated with toxicity, low-throughput, and/or difficulty to target certain cell types. In this study, we developed and evaluated new high-throughput intracellular delivery methods for the efficient delivery of macromolecules while maintaining high cell viability. First, we studied the feasibility of using an array of nanoneedles, with sharp tip diameters in the range of tens of nanometers, to physically make transient holes in cell membranes for intracellular delivery. Puncture loading and centrifuge loading methods were developed and assessed for the effect of various experimental parameters on cell viability and delivery efficiency of fluorescent molecules. In both methods, high-throughput intracellular delivery was feasible by creating transient holes in cell membranes with the sharp tips of the nanoneedles. The second physical intracellular delivery method we studied was a novel microfluidic device that created transient holes in the cell membrane by mechanical deformation and shear stress to the cell. We observed efficient delivery of fluorescent molecules and studied the effect of device design and flow pressure on the delivery efficiency compared to data in the literature. We accounted for cell loss and clogging in the microfluidic devices and determined the true loss of cell viability associated with this method. Lastly, we investigated the possibility of intracellular delivery using nanoparticles on a leukemia cell line. Among number of materials for nanoparticles tested, mesoporous silica/poly-L-lysine nanoparticles were selected for further intracellular delivery study based on cell viability and intracellular delivery capability. We demonstrated the co-delivery of protein and plasmid by encapsulating into and coating onto the surface of the nanoparticles, respectively, which would be advantageous for certain therapeutic strategies. In summary, this work introduced two new intracellular delivery methods involving nanoneedles and novel nanoparticles, and provided an early, independent assessment of microfluidic delivery, showing the strengths and weaknesses of each method. These methods can be further optimized for a number of laboratory and clinical applications with continued research.
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PERFORMANCE ISSUES IN MIXING CELLULAR AND MANET FOR iNETBabalola, Olusola 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / In the iNET community, communications between Test Articles (TA) and Ground Station (GS) can be over a long distance course that places a TA at ranges where they are sometimes beyond line-of-sight (LoS) or over-the-horizon communications with the GS. In other cases, the TA moves out of the LoS communications range of GS. There is a need to provide communications to these TA at these over-the-horizon locations. The Cellular and Mobile Ad Hoc Network (MANET) have attracted a lot of attention recently and the field continues to grow daily. The cellular network offers high capacity but limited in coverage due to its fixed base infrastructure. MANET on the other hand has a wide range of coverage and also high data rates, but its throughput performance is reduced at high capacity. The MANET cellular mixture network (MCMN) has been proposed to provide an extensive communications between the TA and GS in the iNET environment. This work presents a performance evaluation and analysis of the two different networks with respect to the performance needs of iNET environment which include coverage and throughput.
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PERFORMANCE EVALUATION OF MANET ROUTING PROTOCOLSShah, Syed Iftikhar Hussain, Shaheed, Syed Hassan January 2011 (has links)
The research study determines OPNET simulation to evaluate the MANET routing protocols i.e. AODV, DSR, GRP and OLSR performance for HTTP and FTP base application traffic. Results from the simulation result helps to measure the performance matrix i.e. packet delivery fraction, normalized routing load, throughput and end to end delay. Scalar values are extracted from simulation to plot desired performance graphs to analyze. The research results and conclusion produces enough information for the selection of best routing protocol for MANET in terms of HTTP and FTP application types.
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SQ-CSMA : universally lowering the delay of queue-based CSMA/CAGanesh, Rajaganesh 1987- 14 October 2014 (has links)
Recent works show that, by incorporating queue length information, CSMA/CA multiple access protocols can achieve maximum throughput in general ad-hoc wireless networks. In all of these protocols, the aggressiveness with which a link attempts to grab the channel is governed solely by its own queue, and is independent of the queues of other interfering links. While this independence allows for minimal control signaling, it results in schedules that change very slowly. This causes starvation and delays - especially at moderate to high loads. In this work we add a very small amount of signaling - an occasional few bits between interfering links. These bits allow us a new functionality: switching - a link can now turn off its interfering links with a certain probability. The challenge is ensuring maximum throughput and lower delay via the use of this new functionality. We develop a new protocol - Switch-enabled Queue-based CSMA (SQ-CSMA) - that uses switching to achieve both of these objectives. This simple additional functionality, and our protocol to leverage it, can be “added on'' to every existing CSMA/CA protocol that uses queue lengths. Interestingly, we see that in every case it has a significant positive impact on delay, universally furthering the performance of existing protocols. / text
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The Generation of Affinity Reagents Using High-throughput Phage Display and Building the Foundations of a Novel High-throughput Intrabody PipelineEconomopoulos, Nicolas 07 December 2011 (has links)
Phage display technology has emerged as the dominant approach in antibody engineering. Here I describe my work in developing a high-throughput method of reliably generating intracellular antibodies. In my first data chapter, I present the first known high-throughput pipeline for antibody-phage display libraries of synthetic diversity and I demonstrate how increasing the scale of both target production and library selection still results in the capture of antibodies to over 50% of targets. In my second data chapter, I present the construction and validation of a novel scFv-phage library that will serve as the first step in my proposed intrabody pipeline. Antibodies obtained from this library will be screened for functionality using a novel yeast-two-hybrid approach and have numerous downstream applications. This high-throughput pipeline is amenable to automation and can be scaled up to thousands of domains, resulting in the potential generation of many novel therapeutic reagents.
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The Generation of Affinity Reagents Using High-throughput Phage Display and Building the Foundations of a Novel High-throughput Intrabody PipelineEconomopoulos, Nicolas 07 December 2011 (has links)
Phage display technology has emerged as the dominant approach in antibody engineering. Here I describe my work in developing a high-throughput method of reliably generating intracellular antibodies. In my first data chapter, I present the first known high-throughput pipeline for antibody-phage display libraries of synthetic diversity and I demonstrate how increasing the scale of both target production and library selection still results in the capture of antibodies to over 50% of targets. In my second data chapter, I present the construction and validation of a novel scFv-phage library that will serve as the first step in my proposed intrabody pipeline. Antibodies obtained from this library will be screened for functionality using a novel yeast-two-hybrid approach and have numerous downstream applications. This high-throughput pipeline is amenable to automation and can be scaled up to thousands of domains, resulting in the potential generation of many novel therapeutic reagents.
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Searching for Radiosensitizers: Development of a Novel Assay and High-throughput ScreeningKatz, David 24 February 2009 (has links)
The colony formation assay (CFA) is the gold standard for measuring cytotoxic effects on cells. To increase efficiency, the CFA was converted to a 96-well format using an automated colony counting algorithm. The 96-well CFA was validated using ionizing radiation (IR) on the FaDu and A549 cancer cell lines. Its ability to evaluate combination therapies was investigated using cisplatin and IR. The 96-well CFA was transferred to a robotic platform for evaluation as a high-throughput screen (HTS) readout for the discovery of novel anti-cancer compounds, and radiosensitizers. Screening yielded eight putative anti-cancer hits, and five putative radiosensitizing hits. Secondary screening confirmed 6/8 anti-cancer compounds, and 0/5 radiosensitizing compounds. Thus, the 96-well CFA can be adopted as an alternative assay to the 6-well CFA in the evaluation of cytotoxicity in vitro, providing a possible readout to be utilized in HTS for discovering anti-cancer compounds, but with limited applicability in discovering radiosensitizers.
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Adaptive load balancing routing algorithms for the next generation wireless telecommunications networksTsiakas, Panagiotis January 2009 (has links)
With the rapid development of wireless networks, mesh networks are evolving as a new important technology, presenting a high research and commercial interest. Additionally, wireless mesh networks have a wide variety of applications, offering the ability to provide network access in both rural and urban areas with low cost of maintenance. One of the main functionalities of a wireless mesh network is load balancing routing, which is the procedure of finding the best, according to some criteria, routes that data need to follow to transfer from one node to another. Routing is one of the state-of-the-art areas of research because the current algorithms and protocols are not efficient and effective due to the diversity of the characteristics of these networks. In this thesis, two new routing algorithms have been developed for No Intra-Cell Interference (NICI) and Limited Intra-Cell Interference (LICI) networks based on WiMAX, the most advanced wireless technology ready for deployment. The algorithms created are based on the classical Dijkstra and Ford-Fulkerson algorithms and can be implemented in the cases of unicast and multicast transmission respectively.
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