453 research outputs found

    Electronic Travel Aid for Visually Impaired People Along with a Panic Alert System

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    There are many issues over which humans have no control. Blindness is one of such issues. It snatches the vivid visual beauty of the world from an individual’s life.But missing the beauty of nature becomes one of the last worries of such people as they have to face numerous difficulties in order to perform even the most basics of tasks in their day to day life. One of their most important problems is of transport, such as crossing roads, traveling in trains, or in any other public places. A visually impaired person to survive the fittest in this world, the person must go through all the obstacles without the guidance of others. One of the most important measures to avoid the obstacle by the blind is to provide an assistive implementation, which can help to wander on their own. The main aim of this project is to provide an assistive technology used for the purpose of enhancing the mobility of the blind pedestrian which is commonly referred to as Electronic Travel Aid (ETA) and to motivate the blind without having the inferior feeling of their problem and pay away the blind to move on their own . In this project, a smart guiding ETA is used to guide the user to sense the obstacle before them. This device eliminates the requirement of human assistance for blind while traveling outside. It will identify all obstacles in the path with the help of various sensors installed in it. The microcontroller will retrieve data and pass it on as vibrations which will notify the user about hurdles

    Studies on efficiencies of electrochemiluminescence of rubrene

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    The electrochemiluminescence efficiencies of rubrene system has been obtained by using the transient method in a variety of solvents. The efficiencies are in the range of 0·11×10-3-4·1×10-2. The mixed system efficiencies are less at least by an order of magnitude in all the solvents except in dimethylsulphoxide. The variation in efficiencies of the pure and mixed systems is explained on the basis of mechanistic differences. In the applied magnetic field, the electrochemiluminescence efficiency of the pure system increases by about 7% and of the mixed system by about 18-25%

    ADVANCED EMBEDDED SYSTEM ASSISTED GSM AND RFID BASED SMART SCHOOL MANAGEMENT SYSTEM

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    ABSTRACT: Among the various technological devices and systems, global system for mobile communication (GSM) is believed as an efficient and fast enough technique that can perform efficient, real time object identification and fast reporting. GSM based tracking system will pass complete information about, where the object (student) and its activities. The RFID system is utilized as a board module to attach the parts of the object (bag, identity card, tag, etc) and follow the object then and there. The designed model is studied under laboratory scale and the results are analysed. Keywords: GSM, RFID, PIC Microcontroller, Security, GSM modem. I.INTRODUCTION The risk of insecure is increasing with increasing populations, as the consequence, large magnitude of hijacks is reported. The major risk faced by the school management as well as the parental side is that the identification of the location of the pupils and their safety measures. The statistical reports perceive that most of the students are hijacked, when they are crossing the school boundary or school entrance area Advanced embedded system assisted GSM and RFID based smart school management system is used to give an access for the operation by habitual recognition of the person based upon the RFID tag information. As an example, for entrance control of an organization, the RFID tag and its reader are designed with predefined unique code of tag for individual school student. Whenever the tag is read by reader, it compares the code with the predefined codes in the machine. On the basis of correctness of the information, it sends an acknowledgement (in the form of text message) to the parents of that particular student and the same protocol is followed for all the pupils of the school. Another important feature of the system is that it maintains a record of attendance about the pupil (i.e.) "in time" "out time" which can be further transferred to the administrator via network systems. Through which we can easily compute the attendance status of the students within no time. This machine can also help to avoid human involvement in keeping the attendance record. Thus, reduction of the manpower held in the organization. This machine ensures accurate access control and record keeping. II. DESIGN AND CONSTRUCTION DETAILS A. RFID: Many types of RFID exist, but at the highest-level, we can classify RFID devices into two classes namely, active and passive tags. Active tags require power source either connected to powered infrastructure or use energy stored in an integrated battery. In the laterals, tag's lifetime is limited by stored energy, balanced against the number of read operations. As an example, an active tag is the transponder attached to an aircraft that identify the national origin. The numbers insisted in the tags represent the identification number of the candidate. The RFID utilized in the current system is given below

    The deuterium effect on electrochemiluminescence efficiencies of anthracene and phenanthrene

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    The effect of deuteration on the electrochemiluminescence (ECL) efficiencies of the mixed systems containing anthracene or phenathrene has been examined using the single light pulse in the double potential programme. Deuteration of anthracene or phenanthrene decreases the ECL efficiencies by factors of 1·2-16·0. This decrease appears to arise from the quenching of the triplets by radical ions in solution. The quenching factors are estimated by using Marcus theory of electron transfer reactions

    Bimodality and hysteresis in systems driven by confined L\'evy flights

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    We demonstrate occurrence of bimodality and dynamical hysteresis in a system describing an overdamped quartic oscillator perturbed by additive white and asymmetric L\'evy noise. Investigated estimators of the stationary probability density profiles display not only a turnover from unimodal to bimodal character but also a change in a relative stability of stationary states that depends on the asymmetry parameter of the underlying noise term. When varying the asymmetry parameter cyclically, the system exhibits a hysteresis in the occupation of a chosen stationary state.Comment: 4 pages, 5 figures, 30 reference

    Quantitative Imaging of Protein-Protein Interactions by Multiphoton Fluorescence Lifetime Imaging Microscopy using a Streak camera

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    Fluorescence Lifetime Imaging Microscopy (FLIM) using multiphoton excitation techniques is now finding an important place in quantitative imaging of protein-protein interactions and intracellular physiology. We review here the recent developments in multiphoton FLIM methods and also present a description of a novel multiphoton FLIM system using a streak camera that was developed in our laboratory. We provide an example of a typical application of the system in which we measure the fluorescence resonance energy transfer between a donor/acceptor pair of fluorescent proteins within a cellular specimen.Comment: Overview of FLIM techniques, StreakFLIM instrument, FRET application

    The deexcitation of the S<SUB>1</SUB> state of aminoanthraquinones: a steadystate and timeresolved study

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    The non-radiative processes of deactivation from the lowest singlet excited state of aminoanthraquinones have been studied using steady-state and time-resolved methods. The fluorescence decay rate constant, kf correlates well with the solvent polarity parameter, ET(30), in nonhydrogen bonding solvents. Large deuterium isotope effects in fluorescence lifetimes (&#964;f) and quantum yields (&#934;f) are observed in the case of 1-amino (AAQ) and 1-methylaminoanthraquinones (MAQ), where the S1 state is mainly deactivated through internal conversion to the ground state. The temperature-dependence of the fluorescence quantum yields of various aminoanthraquinones was also investigated. The &#934;f and &#964;f exhibited strong temperature-dependence in the case of 1-acetylaminoanthraquinone (ACAQ). In the case of ACAQ, the intersystem crossing to the triplet state is a major deactivation channel from the S1 and in this derivative a close-lying T2 state seems to be responsible for the high kisc rate. The fluorescence properties of 1,5-diaminoanthraquinone (DAQ) are affected by intermolecular hydrogen bonding with alcohols. Increasingn-alkyl chain length in the case of l-(n-alkyl)aminoanthraquinones from methyl to butyl does not produce any change in the fluorescence properties, whereas a hydroxypropyl substitution results in a small decrease of &#934;f and &#964;f in these compounds, indicating an interaction of the hydroxyl group with the carbonyl group of the aminoanthraquinones

    Immune Complex-Induced, Nitric Oxide-Mediated Vascular Endothelial Cell Death by Phagocytes Is Prevented with Decoy FcyReceptors

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    Autoimmune vasculitis is an endothelial inflammatory disease that results from the deposition of immune-complexes (ICs) in blood vessels. The interaction between Fcgamma receptors (FcyRs) expressed on inflammatory cells with ICs is known to cause blood vessel damage. Hence, blocking the interaction of ICs and inflammatory cells is essential to prevent the IC-mediated blood vessel damage. Thus we tested if uncoupling the interaction of FcyRs and ICs prevents endothelium damage. Herein, we demonstrate that dimeric FcyR-Igs prevented nitric oxide (NO) mediated apoptosis of human umbilical vein endothelial cells (HUVECs) in an in vitro vasculitis model. Dimeric FcyR-Igs significantly inhibited the IC-induced upregulation of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) release by murine monocytic cell line. However, FcyR-Igs did not affect the exogenously added NO-induced upregulation of pro-apoptotic genes such as Bax (15 fold), Bak (35 fold), cytochrome-C (11 fold) and caspase-3 (30 fold) in HUVECs. In conclusion, these data suggest that IC-induced NO could be one of the major inflammatory mediator promoting blood vessel inflammation and endothelial cell death during IC-mediated vasculitis which can be effectively blocked by dimeric decoy FcyRs

    Genetic analysis of patients with Fuchs endothelial corneal dystrophy in India

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    <p>Abstract</p> <p>Background</p> <p>Mutations in <it>COL8A2 </it>gene which encodes the collagen alpha-2 (VIII) chain have been identified in both familial and sporadic cases of Fuchs endothelial corneal dystrophy (FECD). Heterozygous mutations in the <it>SLC4A11 </it>gene are also known to cause late-onset FECD. Therefore we screened for <it>COL8A2</it>, <it>SLC4A11 </it>gene variants in Indian FECD patients.</p> <p>Methods</p> <p>Eighty patients with clinically diagnosed FECD and 100 age matched normal individuals were recruited. Genomic DNA was isolated from peripheral blood leukocytes. Mutations in <it>COL8A2</it>, <it>SLC4A11 </it>coding regions were screened using bi-directional sequencing. Fischer's exact test or Pearson's chi squared test were used to predict the statistical association of genotypes with the phenotype.</p> <p>Results</p> <p>Screening of <it>COL8A2 </it>gene revealed 2 novel c.1610G>A, c.1643A>G and 3 reported variations c.112G>A, c.464G>A and c.1485G>A. In <it>SLC4A11 </it>gene, novel c.1659C>T, c.1974C>T and reported c.405G>A, c.481A>C and c.639G>A variants were identified. However all the variations in both the genes were also present in unaffected controls.</p> <p>Conclusions</p> <p>This is the first study analysing <it>COL8A2 </it>gene in Indian patients with FECD. No pathogenic mutations were identified in <it>COL8A2</it>. Merely silent changes, which showed statistically insignificant association with FECD, were identified in the screening of <it>SLC4A11 </it>gene. These results suggest that <it>COL8A2</it>, <it>SLC4A11 </it>genes may not be responsible for FECD in patients examined in this study.</p
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