Issues in autonomous mobile sensor networks

Autonomous mobile sensor networks consist of a number of autonomous mobile robots equipped with various sensors and tasked with a common mission. This thesis considers the topology control of such an ad hoc mobile sensor network. In particular, I studied the problem of controlling the size, with respect to a distance metric, of the network for general interactive forcing among agents. Developed is a stability result, allowing one to design force laws to control the spread of the network. Many of the current results assume a known and/or fixed topology of the graph representing the communication between the nodes, i.e. the graph laplacian is assumed constant. They also assume fixed and known force-laws. Hence, the results are limited to time-invariant dynamics. The research considers stability analysis of sensor networks, unconstrained by specific forcing functions or algorithms, and communication topologies. Since the graph topologies are allowed to change as the agents move about, the system dynamics become discontinuous in nature. Filippov’s calculus of differential equations with discontinuous right hand sides is used to formally characterize the multi-agent system with the above attributes. Lyapunov’s Stability Theory, applied to discontinuous systems, is then used to derive bounds on the norm of the system states given bounds on its initial states and input. The above derived stability results lend themselves to the derivation of methods for the design of algorithms or force-laws for mobile sensor networks. The efficacy of the derived results is illustrated through several examples where it is shown how they may be used for synthesizing a topology managing strategy. Examples are given of designing force-laws that limit the network in a desired area

A rare presentation of Salmonella Paratyphi B associated enteric fever and liver abscess: A case report and brief review

A pyogenic liver abscess (PLA) is a rare complication of enteric fever and is a potentially life-threatening condition. Here, we report a case of PLA secondary to enteric fever caused by Salmonella Paratyphi B in a 60-year-old male with diabetes mellitus and chronic alcoholism, who presented with fever, jaundice and abdominal pain. An ultrasound of the abdomen revealed a large abscess involving the left lobe of the liver with air-fluid level. Pus aspirated from the liver abscess yielded growth of Salmonella Paratyphi B which was susceptible to most of the commonly tested antibiotics. A Widal test performed also showed significant titers for Salmonella Paratyphi B. Percutaneous aspiration along with appropriate intravenous antibiotics resulted in a favourable clinical outcome in this patient

Alterations in Cell-Extracellular Matrix Interactions during Progression of Cancers

Cancer progression is a multistep process during which normal cells exhibit molecular changes that culminate into the highly malignant and metastatic phenotype, observed in cancerous tissues. The initiation of cell transformation is generally associated with genetic alterations in normal cells that lead to the loss of intercellular- and/or extracellular-matrix- (ECM-) mediated cell adhesion. Transformed cells undergo rapid multiplication and generate more modifications in adhesion and motility-related molecules which allow them to escape from the original site and acquire invasive characteristics. Integrins, which are multifunctional adhesion receptors, and are present, on normal as well as transformed cells, assist the cells undergoing tumor progression in creating the appropriate environment for their survival, growth, and invasion. In this paper, we have briefly discussed the role of ECM proteins and integrins during cancer progression and described some unique conditions where adhesion-related changes could induce genetic mutations in anchorage-independent tumor model systems

Design and Development of Application to Transport Layer Protocol for Smart Collaboration of Intelligent Devices

There are varieties of smart devices – devices with hardware and significant amount of software to mine data from the hardware in and around us, like in Home we have smart phones, smart TV, Laptops, smart refrigerators, etc. There is a need for each device of different size and capability to collaborate. That brings us to first and most important step of “inter- device communication”, which can be deployed on any device without much further fuss. Simple yet secure channel of communication, which does not require much of computing power or memory is real time in nature and is extensible towards future. The challenge is to develop a simple Application Layer protocol, which uses existing TCP/IP technology to interconnect these devices and enable bi-directional communication, which is minimalistic in terms of size of payloads – data available at each of these smart devices- and will use the WWW (world wide web’s) most versatile tool – XML for making encoding data/information in a format that is both human-readable and machine-readable DOI: 10.17762/ijritcc2321-8169.15063

3-D analysis of F-actin in stereocilia of cochlear hair cells after loud noise exposure

Fluorescence microscopy can be a useful tool in the early detection of pathological changes in the stereocilia of outer hair cells which have undergone acoustic overstimulation. Fluorescent phalloidin, a highly specific F-actin stain, can be used to label F-actin in stereocilia. In this study, phalloidin label is used to determine quantitative changes of F-actin in the stereocilia of guinea pigs exposed to loud noise (117 dB; octave band noise, centered at 1 kHz; 4 h). Reliably determining three-dimensional (3-D) structural changes in stereocilia is a challenging problem in optical microscopy since stereocilia diameter is close to the optical resolution limit. In order to alleviate the problem, a computational 3-D microscopy technique is used (Avinash et al., 1992). Whole-mounts of the cochlear second and third turns were examined in a Leitz Orthoplan microscope through a Leitz Plan Apo objective lens (100 x ; 1.32 N.A.; 170/0.17). Images were acquired with a charge-coupled device camera where the focus was shifted in 0.2 [mu]m steps using a piezoelectric translator. Images were processed with the appropriate point spread function of the optical system. Analysis of control cochleas indicate that our technique can resolve single stereocilia and distinguish between various intensities of label along each stereocilia. In noise-exposed cochleas, our data show length and intensity changes in the phalloidin label. These results suggest that both depolymerization and polymerization of F-actin can occur in stereocilia of outer hair cells after acoustic overstimulation. Our findings demonstrate the applicability of computational 3-D microscopy to quantitative and qualitative analysis of stereocilia.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30805/1/0000463.pd

Laser Doppler velocimetry of basilar membrane vibration

A method is described for the measurement of basilar membrane (BM) vibration using a commercially made laser Doppler velocimeter (LDV). The instrumentation was coupled to a compound microscope which served to visualize reflective glass microbeads placed on the BM. The laser beam of the LDV was focused in the microscope object plane and positioned over the reflective bead. We show examples of frequency tuning curves and displacement input/output intensity functions obtained with the technique.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29478/1/0000564.pd

Review Article Alterations in Cell-Extracellular Matrix Interactions during Progression of Cancers

Cancer progression is a multistep process during which normal cells exhibit molecular changes that culminate into the highly malignant and metastatic phenotype, observed in cancerous tissues. The initiation of cell transformation is generally associated with genetic alterations in normal cells that lead to the loss of intercellular-and/or extracellular-matrix-(ECM-) mediated cell adhesion. Transformed cells undergo rapid multiplication and generate more modifications in adhesion and motilityrelated molecules which allow them to escape from the original site and acquire invasive characteristics. Integrins, which are multifunctional adhesion receptors, and are present, on normal as well as transformed cells, assist the cells undergoing tumor progression in creating the appropriate environment for their survival, growth, and invasion. In this paper, we have briefly discussed the role of ECM proteins and integrins during cancer progression and described some unique conditions where adhesion-related changes could induce genetic mutations in anchorage-independent tumor model systems

Propagation of pure fetal and maternal mesenchymal stromal cells from terminal chorionic villi of human term placenta

Long term propagation of human fetal Mesenchymal Stromal Cells (MSC) in vitro has proven elusive due to limited availability of fetal tissue sources and lack of appropriate methodologies. Here, we have demonstrated the presence of fetal and maternal cells within the tips of Terminal Chorionic Villi (TCV) of normal human term placenta and we have exploited inherent differences in the adhesive and migratory properties of maternal vs. fetal cells, to establish pure MSC cultures of both cell types. The origin and purity of each culture was confirmed by X-Y chromosome-specific Fluorescence In Situ Hybridization (FISH) and Short Tandem Repeat (STR) genotyping. This is the first demonstration of fetal and maternal cells in the TCV of human term placenta and also of deriving pure fetal MSC cultures from them. The concomitant availability of pure cultures of adult and fetal MSC from one tissue provides a good system to compare genetic and epigenetic differences between adult and fetal MSCs and also to generate new models of cell based therapies in regenerative medicine