67 research outputs found

    Detection of indoor and outdoor stairs

    Get PDF
    There are a few applications in which stairs must be detected, for example for aiding blind persons during navigation and for autonomous robots which must rely on vision. . In this paper we present a very simple algorithm for detecting stairs, both in indoor and outdoor environments, when the camera is at a distance of approximately five meters from the stairs. The problem is hard to solve due to different factors like lighting, different constructions, materials and view angles. However, first results are very promising, although false positive and negative detections cannot yet be avoided

    Buthionine sulfoximine inhibits cytopathic effects and apoptosis induced by infection with AIK-HDC strain of measles virus

    Get PDF
    Background: Measles virus (MV) is a highly contagious agent which causes a major health problem in developing countries. We studied the effect of buthionine sulfoximine (BSO) on the replication of an AIK-HDC strain of MV and its induced apoptosis in Vero cell lines. Methods: In this study, toxicity of BSO on Vero cells was investigated first, resulted in determination of sub-lethal or non-toxic concentration zone of BSO for cells. Next, anti-viral effect of BSO at various time limits was evaluated and virus titer was determined at each stage either as 50 tissue culture infective dose (TCID) 50 or by plaque assay method. Using specific anti-measles IgG, anti-viral effect of BSO on MV replication cycle was evaluated through indirect immunofluorescence assay, meanwhile presence of viral RNA was investigated by RT-PCR and gel electrophoresis. Results: According to the experiments, BSO, at concentration of 50 μM, markedly inhibited the cytopathic effect (CPE) induced by MV. BSO also significantly inhibited apoptosis induced by MV. BSO either influences replication of MV genome, or may inhibit virion formation. Conclusion: These results suggest that the inhibition of CPE and apoptosis by BSO induced by MV may be associated with the effect of BSO on viral RNA genome. Therefore, it is suggested that MV infections can induce apoptosis through the activation of a common pathway that can be inhibited by BSO

    Realtime local navigation for the blind: detection of lateral doors and sound interface

    Get PDF
    Worldwide there are about 285 million visually impaired persons, of which 39 million are blind and the others have low vision. Almost all systems designed to assist them are quite complex and expensive, but most blind persons do not have advanced technical assistance and they are rather poor. We are therefore developing a low-cost navigation aid which can be afforded by almost all blind persons: basically, the ultimate goal is to use only a mobile phone with a built-in camera. This aid complements the white cane, it is easily portable, and it is not a hindrance when walking with the cane. The system will have an easy and intuitive interface, yet providing assistance in local and global navigation in realtime. In this paper we present the progress concerning local navigation. Path and obstacle detection just beyond the reach of the cane is now supplemented by detection of doors in corridors. This is necessary for localization, i.e., for developing a better impression of the environment and for finding a specific room. A sophisticated sound interface can assist the user for centering on paths like sidewalks and corridors, alerting to looming obstacles for avoiding them

    High-Risk and Low-Risk Human Papillomavirus in Esophageal Squamous Cell Carcinoma at Mazandaran, Northern Iran

    Get PDF
    Cancers are the second most common cause of nonaccidental deaths in Iran, following cardiovascular deaths. Mazandaran, near the Caspian Littoral at north of Iran have identified as a several-high incidence area for Esophageal Squamous Cell Carcinoma (ESCC) in the world. Several associated risk factors, such as dietary and cultural habits, infectious agents, nutritional deficiencies, too much use of tobacco and alcohol and infection to certain DNA tumor viruses (HPVs), including environmental and genetic factors are attributed to this disease. To explore this issue, we analyzed HPV DNA prevalence and HPV types together in relation to tumor sites a high-incidence population. Archived tissue blocks from 46, 69 and 62 upper, middle and lower third of esophagus, respectively from ESCC patients were evaluated for the presence of HPV DNA by PCR using the degenerate HPV L1 consensus primer pairs MY09/MY11. The positive specimens were evaluated by Real-time PCR to determine HPV genotypes. From the 49 HPV positive cases, of ESCC patients, 5 (23.1%), 11 (55 %) and 9 (56.3 %) of upper, middle and lower third of ESCC specimens, respectively were positive by at least one high and one low-risk HPV genotypes. In general, HPV45 and HPV11 were the most common high- risk and low-risk HPV genotypes in HPV L1 positive cases, respectively, followed by HPV6, HPV52 and HPV39. Therefore, the high prevalence of HPV DNA in different anatomical sites of ESCC patients from the Mazandaran region in North of Iran provides more evidence for a role of HPV in this cancer

    Primary Human mDC1, mDC2, and pDC Dendritic Cells Are Differentially Infected and Activated by Respiratory Syncytial Virus

    Get PDF
    Respiratory syncytial virus (RSV) causes recurrent infections throughout life. Vaccine development may depend upon understanding the molecular basis for induction of ineffective immunity. Because dendritic cells (DCs) are critically involved in early responses to infection, their interaction with RSV may determine the immunological outcome of RSV infection. Therefore, we investigated the ability of RSV to infect and activate primary mDCs and pDCs using recombinant RSV expressing green fluorescent protein (GFP). At a multiplicity of infection of 5, initial studies demonstrated ∼6.8% of mDC1 and ∼0.9% pDCs were infected. We extended these studies to include CD1c−CD141+ mDC2, finding mDC2 infected at similar frequencies as mDC1. Both infected and uninfected cells upregulated phenotypic markers of maturation. Divalent cations were required for infection and maturation, but maturation did not require viral replication. There is evidence that attachment and entry/replication processes exert distinct effects on DC activation. Cell-specific patterns of RSV-induced maturation and cytokine production were detected in mDC1, mDC2, and pDC. We also demonstrate for the first time that RSV induces significant TIMP-2 production in all DC subsets. Defining the influence of RSV on the function of selected DC subsets may improve the likelihood of achieving protective vaccine-induced immunity
    corecore