High Energy Emission Processes in OJ 287 during 2009 Flare

The broadband spectrum of a BL Lac object, OJ 287, from radio to $\gamma$-rays obtained during a major $\gamma$-ray flare detected by \emph{Fermi} in 2009 are studied to understand the high energy emission mechanism during this episode. Using a simple one-zone leptonic model, incorporating synchrotron and inverse Compton emission processes, we show that the explanation of high energy emission from X-rays to $\gamma$-rays, by considering a single emission mechanism, namely, synchrotron self-Compton (SSC) or external Compton (EC) requires unlikely physical conditions. However, a combination of both SSC and EC mechanisms can reproduce the observed high energy spectrum satisfactorily. Using these emission mechanisms we extract the physical parameters governing the source and its environment. Our study suggests that the emission region of OJ 287 is surrounded by a warm infrared (IR) emitting region of $\sim 250 \, K$. Assuming this region as a spherical cloud illuminated by an accretion disk, we obtain the location of the emission region to be $\sim 9 pc$. This supports the claim that the $\gamma$-ray emission from OJ 287 during the 2009 flare arises from a location far away from the central engine as deduced from millimeter-gamma ray correlation study and very long baseline array images.Comment: 22 pages, 7 figures, 1 table, accepted for publication in MNRA

Brightest Fermi-LAT Flares of PKS 1222+216: Implications on Emission and Acceleration Processes

We present a high time resolution study of the two brightest $\gamma$-ray outbursts from a blazar PKS 1222+216 observed by the \textit{Fermi} Large Area Telescope (LAT) in 2010. The $\gamma$-ray light-curves obtained in four different energy bands: 0.1--3, 0.1--0.3, 0.3--1 and 1--3 GeV, with time bin of 6 hr, show asymmetric profiles with a similar rise time in all the bands but a rapid decline during the April flare and a gradual one during the June. The light-curves during the April flare show $\sim 2$ days long plateau in 0.1--0.3 GeV emission, erratic variations in 0.3--1 GeV emission, and a daily recurring feature in 1--3 GeV emission until the rapid rise and decline within a day. The June flare shows a monotonic rise until the peak, followed by a gradual decline powered mainly by the multi-peak 0.1--0.3 GeV emission. The peak fluxes during both the flares are similar except in the 1--3 GeV band in April which is twice the corresponding flux during the June flare. Hardness ratios during the April flare indicate spectral hardening in the rising phase followed by softening during the decay. We attribute this behavior to the development of a shock associated with an increase in acceleration efficiency followed by its decay leading to spectral softening. The June flare suggests hardening during the rise followed by a complicated energy dependent behavior during the decay. Observed features during the June flare favor multiple emission regions while the overall flaring episode can be related to jet dynamics.Comment: 17 pages, 9 figures, 4 tables, accepted for publication in Ap

Transition from Modernity to Post-modernity

The era of enlightenment is known as “mother of modernityâ€. It has promoted human rationality, scientific development, and human supremacy and paves the way for the decline of religious understanding of the society. The rise of human rationality, materialization of industry, invention of printing press and rising trend of democratic principle, emerging market economy and technological development are characterised as modernity.  The idea of modernity is first stage of human era where human beings were treated as supreme authority of their spheres. With modernity, the concept of nation/state emerged which has the credit to organise the world, promote the rights of the individuals and pay its emphasis on the construction of the democratic society, participatory politics and free individuals. But modernity is criticised by scholars like Perry Anderson, who argue that modernity has actually created another layer and made society absolute. It has inserted empirical documentation and rejected the persons’ observation, including local reality. With these critiques, post-modernity emerged which has questioned the foundation of modernity. It advocated for ‘bottom to approach’ unlike modernity. The main objective of this paper to analysed the main tenets of modernity and discuss the actual principle of post-modernity. This analytical paper concludes with the major critics of post-modernity by taking the author’s understanding about modernity and post-modernity

Speed and Torque Estimation of BLDC using DTC and Sliding Mode Observer

This paper presents speed and torque estimation for Brushless DC (BLDC) motors with non-sinusoidal back electromotive force using six switch inverter and DTC technique. The 180 conduction mode is the more popular method used for three-phase drives but here we use two-phase conduction mode. A simple approach is discussed n how to reduce ripples in the estimated torque at low frequency operation. A simple look-up table at a pre-defined sampling time is used to select the inverter voltage space vectors and the quasi-wave current is obtained. Estimation of electromagnetic torque for BLDC drives is the key issue and so sensor-less control method are used. The sliding mode observer estimates the back-EMF and generates torque, as under sliding mode observer error equation is reduced and it makes stability easier. Only the measurements of the stator currents is used in the estimation of back-EMF waveform. The electromagnetic torque and the rotor speed is estimated using values from Sliding Mode Observer. Fuzzy Gain Scheduling method is used to tune the parameters because this scheme uses human expertise on PID gain scheduling can be represented in fuzzy rules. Furthermore, better control performance can be expected in the proposed method than that of the PID controllers with fixed parameters and the gains of the sliding mode observer are tuned manually. The effectiveness of the proposed scheme is verified by using simulation results. Keywords: BLDC, DTC, Sliding Mode Observer(SMO), PID Controller, Fuzzy Gain Scheduling, Estimated Rotor speed, Estimated Torque, Estimated Back-EMF

Novel approaches for ungual and trans-ungual delivery of drugs

Topical therapy is commonly used for the treatment of nail diseases such as onychomycosis and nail psoriasis due to less severe side effects, non-invasiveness, direct drug delivery at the site of infection, patient compliance and lower cost of treatment. However, topical treatment is limited due to poor permeability and hard nature of nail plate. The main objective of first project was to investigate the penetrability of apremilast into and across the nail plate, folloby the preparation of a novel nail lacquer formulation to improve its ungual and trans-ungual permeation for the treatment of nail psoriasis. Dexpanthenol and salicylic acid were found to be the potential permeation enhancers. The final nail lacquer formulation shothe ability to form a water resistant film on nail plate and delivered significant amount of apremilast into the nail apparatus. In second project, iontophoresis technique was investigated to improve the ungual and trans-ungual permeation of itraconazole for the treatment of onychomycosis. In vitro and ex vivo permeation studies were performed following two protocols, a) pulse application of iontophoresis for 3 days (8 h/day), b) continuous application of iontophoresis for 24 h. The results of in vitro and ex vivo studies demonstrated the feasibility of iontophoresis technique to enhance nail delivery of itraconazole. Pulsed application of iontophoresis was found to be superior over continuous application of iontophoresis in all cases. In third project, a novel hyponychium pathway was investigated to deliver drugs directly into the ventral layer of nail plate and other part of nail apparatus using iontophoresis as an active technique. In vitro and ex vivo studies resulted that hyponychium pathway can be a viable option to deliver significant amount of drug into nail apparatus by the application of iontophoresis technique. In final project, pre-treatment with solid microneedle was investigated to improve the availability of drugs in nail apparatus. The application of microneedles has not been explored before to improve nail delivery of drugs. Microneedle pre-treatment is a novel approach which has already been used to deliver small and large molecules into the skin in a minimally invasive manner

Automatic Intruder Combat System: A way to Smart Border Surveillance

Security and safeguard of international borders have always been a dominant issue for every nation. A large part of a nation’s budget is provided to its defense system. Besides wars, illegal intrusion in terms of terrorism is a critical matter that causes severe harm to nation’s property. In India’s perspective, border patrolling by Border Security Forces (BSF) has already been practiced from a long time for surveillance. The patrolling parties are equipped with high-end surveillance equipments but yet an alternative to the ply of huge manpower and that too in harsh environmental conditions hasn’t been in existence. An automatic mechanism for smart surveillance and combat is proposed in this paper as a solution to the above-discussed problems. Smart surveillance requires automatic intrusion detection in the surveillance video, which is achieved by using optical flow information as motion features for intruder/human in the scene. The use of optical flow in the proposed smart surveillance makes it robust and more accurate. Use of a simple horizontal feature for fence detection makes system simple and faster to work in real-time. System is also designed to respond against the activities of intruders, of which auto combat is one kind of response

Assessment of study among radiography students about how to take informed consent

Background: Consent form is an integral first step before any radiological procedure that engages methods that can be threatening to patients. Future radiographers i.e., radiography students should have sufficient and appropriate knowledge regarding obtaining an informed consent. The aim of my study is to evaluate and assess the knowledge and impart the importance of informed consent form among Radiography students under various conditions.Methods: A questionnaire based retrospective cross-sectional was used to assess the knowledge of informed consent among radiographic students. The study was carried out in radiology department of Maharishi Markandeshwar University. The questionnaire comprised of self-structured MCQs questionnaire consisted of demographic data and basic questions regarding informed consent.Results: Out of 156 undergraduate and postgraduate radiology paramedical students, 87 took part in the study. It was assessed how much information radiography students possess on taking informed consent. The gender ratio was allocated into 2 groups. First group was female consisting of 45 (51.72%) number of participants and second group male consisting of 42 (48.28%) number of students with mean of 21 years.Conclusions: Indulging on the subject of consent form, almost all of the students understood the concept of consent form or had heard about the concept of informed consent to some extent. Maximum students were in favour of classes being held discussing consent form. The statistical data of all participants who gave the correct answer is 81.20%, indicating that radiography students understand and grasp the concept of consent very well

Enhancement of Confidentiality of Data Transmitted over Covert Channel Using Grid Cipher Scheme

In this fast developing world, the interchange of information is playing a key role. Everything needs information and processes them. This interchange of information needs an authentication, confidentiality and integrity. The security of information is provided many algorithms. There are vast numbers of algorithms for symmetry key cipher. All these algorithms have used either complicated keys to encrypt the plain text to cipher text or a complicated algorithms used for it. The level of security of algorithms is dependent on either number of iterations or length of keys. A comparative study have been made with RSA, DES, IDEA, BAM and other algorithms with frequency distribution, bit ratio to check the security level of proposed algorithm. Finally, a comparison has been made for time complexity for encryption of plain text and decryption from cipher text with above existing algorithms

Multi-wavelength Temporal Variability of the Blazar 3C 454.3 during 2014 Activity Phase

We present a multi-wavelength temporal analysis of the blazar 3C 454.3 during the high $\gamma$-ray active period from May-December, 2014. Except for X-rays, the period is well sampled at near-infrared (NIR)-optical by the \emph{SMARTS} facility and the source is detected continuously on daily timescale in the \emph{Fermi}-LAT $\gamma$-ray band. The source exhibits diverse levels of variability with many flaring/active states in the continuously sampled $\gamma$-ray light curve which are also reflected in the NIR-optical light curves and the sparsely sampled X-ray light curve by the \emph{Swift}-XRT. Multi-band correlation analysis of this continuous segment during different activity periods shows a change of state from no lags between IR and $\gamma$-ray, optical and $\gamma$-ray, and IR and optical to a state where $\gamma$-ray lags the IR/optical by $\sim$3 days. The results are consistent with the previous studies of the same during various $\gamma$-ray flaring and active episodes of the source. This consistency, in turn, suggests an extended localized emission region with almost similar conditions during various $\gamma$-ray activity states. On the other hand, the delay of $\gamma$-ray with respect to IR/optical and a trend similar to IR/optical in X-rays along with strong broadband correlations favor magnetic field related origin with X-ray and $\gamma$-ray being inverse Comptonized of IR/optical photons and external radiation field, respectively.Comment: 15 pages, 5 figures, 1 table, MNRAS accepte