Towards Sensor Enhanced Virtual Reality Teleoperation in a Dynamic Environment

A teleoperation interface is introduced featuring an integrated virtual reality based simulation augmented by sensors and image processing capabilities on-board the remotely operated vehicle. The virtual reality system addresses the typical limitations of video-based teleoperation caused by signal lag and limited field of view, allowing the operator to navigate in a continuous fashion. The vehicle incorporates an on-board computer and a stereo vision system to facilitate obstacle detection. It also enables temporary autonomous operation of the vehicle for local navigation around obstacles and automatic re-establishment of the vehicle’s teleoperated state. Finally, the system provides real time update to the virtual environment based on anomalies encountered by the vehicle. System architecture and preliminary implementation results are discussed, and future work focused on incorporating dynamic moving objects in the environment is described

A genetic algorithm-based energy-aware multi-hop clustering scheme for heterogeneous wireless sensor networks

Background: The energy-constrained heterogeneous nodes are the most challenging wireless sensor networks (WSNs) for developing energy-aware clustering schemes. Although various clustering approaches are proven to minimise energy consumption and delay and extend the network lifetime by selecting optimum cluster heads (CHs), it is still a crucial challenge.Methods: This article proposes a genetic algorithm-based energy-aware multi-hop clustering (GA-EMC) scheme for heterogeneous WSNs (HWSNs). In HWSNs, all the nodes have varying initial energy and typically have an energy consumption restriction. A genetic algorithm determines the optimal CHs and their positions in the network. The fitness of chromosomes is calculated in terms of distance, optimal CHs, and the node's residual energy. Multi-hop communication improves energy efficiency in HWSNs. The areas near the sink are deployed with more supernodes far away from the sink to solve the hot spot problem in WSNs near the sink node.Results: Simulation results proclaim that the GA-EMC scheme achieves a more extended network lifetime network stability and minimises delay than existing approaches in heterogeneous nature.peer-reviewe

Mammalian Target of Rapamycin (mTOR) Activity Dependent Phospho-Protein Expression in Childhood Acute Lymphoblastic Leukemia (ALL)

Modern treatment strategies have improved the prognosis of childhood ALL; however, treatment still fails in 25–30% of patients. Further improvement of treatment may depend on the development of targeted therapies. mTOR kinase, a central mediator of several signaling pathways, has recently attracted remarkable attention as a potential target in pediatric ALL. However, limited data exists about the activity of mTOR. In the present study, the amount of mTOR activity dependent phospho-proteins was characterized by ELISA in human leukemia cell lines and in lymphoblasts from childhood ALL patients (n = 49). Expression was measured before and during chemotherapy and at relapses. Leukemia cell lines exhibited increased mTOR activity, indicated by phospho-S6 ribosomal protein (p-S6) and phosphorylated eukaryotic initiation factor 4E binding protein (p-4EBP1). Elevated p-4EBP1 protein levels were detected in ALL samples at diagnosis; efficacy of chemotherapy was followed by the decrease of mTOR activity dependent protein phosphorylation. Optical density (OD) for p-4EBP1 (ELISA) was significantly higher in patients with poor prognosis at diagnosis, and in the samples of relapsed patients. Our results suggest that measuring mTOR activity related phospho-proteins such as p-4EBP1 by ELISA may help to identify patients with poor prognosis before treatment, and to detect early relapses. Determining mTOR activity in leukemic cells may also be a useful tool for selecting patients who may benefit from future mTOR inhibitor treatments

Radiation Induced Apoptosis of Murine Bone Marrow Cells is Independent of Early Growth Response 1 (EGR1)

An understanding of how each individual 5q chromosome critical deleted region (CDR) gene contributes to malignant transformation would foster the development of much needed targeted therapies for the treatment of therapy related myeloid neoplasms (t-MNs). Early Growth Response 1 (EGR1) is a key transcriptional regulator of myeloid differentiation located within the 5q chromosome CDR that has been shown to regulate HSC (hematopoietic stem cell) quiescence as well as the master regulator of apoptosis—p53. Since resistance to apoptosis is a hallmark of malignant transformation, we investigated the role of EGR1 in apoptosis of bone marrow cells; a cell population from which myeloid malignancies arise. We evaluated radiation induced apoptosis of Egr1+/+ and Egr1-/- bone marrow cells in vitro and in vivo. EGR1 is not required for radiation induced apoptosis of murine bone marrow cells. Neither p53 mRNA (messenger RNA) nor protein expression is regulated by EGR1 in these cells. Radiation induced apoptosis of bone marrow cells by double strand DNA breaks induced p53 activation. These results suggest EGR1 dependent signaling mechanisms do not contribute to aberrant apoptosis of malignant cells in myeloid malignancies

Effect of cyclosporin A on murine experimental Salmonellosis

Investigations were undertaken to evaluate the effect of cyclosporin A (CyA) on primary infection of mice with Salmonella typhimurium. Further, its effect on delayed-type hypersensitivity (DTH) and antibody response to porin, an outer membrane protein of S. typhimurium, has been characterized under different CyA regimen. When mice were infected i.p. with 5 * 10(4) live medium virulent organisms, the bacterial growth increased by about 2 log10 in CyA treated mice. CyA administered daily for 2 weeks following immunization with porin caused profound suppression of DTH and both IgM and IgG antibody responses. Given a single dose of CyA 24 h before DTH elicitation, the drug had a marked suppressive effect on DTH, but not on the antibody response to porin. Treatment on days 0-5 following immunization had no effect on the manifestation of the DTH response nor on the anti-porin IgM response whereas an enhanced level of IgG was observed in this group

Detection of porin antigen in serum for early diagnosis of mouse infections with Salmonella typhimurium

The monoclonal antibodies to porin, an outer membrane protein isolated from Salmonella typhimurium and sandwich enzyme linked immunosorbent assay (ELISA) has made possible the detection of porin from sera of S. typhimurium-infected mice. The specificity of the monoclonal antibodies was ascertained based on their cross-reactivity with porins isolated from S. typhi, Shigella flexneri and Escherichia coli and lipopolysaccharide (LPS) of S. typhimurium and E. coli. Serum samples were found to be positive for porin as early as 3 days after intravenous and 5 days after oral infection. In addition, a positive correlation was observed between the bacterial load and the concentration of porin detected in the sera. On the other hand, analysis of sera for anti-porin antibody showed diametrically opposite time kinetics with antigenaemia. These results indicate that porin accumulates in the serum of infected mice much earlier than the appearance of antibodies to porin. Thus detection of porin holds promise for early diagnosis of typhoid

Mechanism of protective immunity induced by porin-lipopolysaccharide against murine salmonellosis.

Investigations were undertaken to characterize the protective immunity induced by porin-lipopolysaccharide (LPS) against Salmonella typhimurium infection in mice. Mice immunized with porin-LPS showed higher levels of antiporin immunoglobulin G than mice which received porin alone. Further, T cells from porin-LPS-immunized mice showed an augmented proliferative response to porin in vitro compared with the response of T cells from porin-injected animals. The passive transfer of anti-LPS antibodies conferred significant protection (17%), while antiporin serum failed to protect mice against lethal challenge, indicating the protective ability of anti-LPS antibodies. However, the transfer of serum obtained from porin-LPS-immunized mice resulted in better protection (30%) than did anti-LPS or antiporin antibodies alone. In contrast to LPS, monophosphoryl lipid A completely failed to induce protection against lethal infection. However, comparable to the effect of LPS, injection of porin with monophosphoryl lipid A enhanced antibody response and the protective ability of porin (81.25%). The transfer of T cells from porin-LPS-immunized mice provided higher levels of protection (47%) against lethal challenge than did T cells from porin-immunized mice (23%). The combination of T cells and serum from porin-immunized mice transferred 36% protection. However, a combination of T cells and serum from porin-LPS-immunized mice conferred the highest level of protection (92%), which was reflected by the number of survivors (100%) in the porin-LPS-immunized group. These results demonstrate that besides the protective effect of anti-LPS antibodies, the ability of LPS to augment humoral and cell-mediated immune responses to porin confers effective protection against Salmonella infection

2007, “Towards sensor enhanced virtual reality teleoperation in a dynamic environment

ABSTRACT A teleoperation interface is introduced featuring an integrated virtual reality based simulation augmented by sensors and image processing capabilities on-board the remotely operated vehicle. The virtual reality system addresses the typical limitations of video-based teleoperation caused by signal lag and limited field of view, allowing the operator to navigate in a continuous fashion. The vehicle incorporates an on-board computer and a stereo vision system to facilitate obstacle detection. It also enables temporary autonomous operation of the vehicle for local navigation around obstacles and automatic re-establishment of the vehicle's teleoperated state. Finally, the system provides real time update to the virtual environment based on anomalies encountered by the vehicle. System architecture and preliminary implementation results are discussed, and future work focused on incorporating dynamic moving objects in the environment is described