High-resolution polarization imaging of the Fermi blazar 3C 279

Ever since the discovery by the Fermi mission that active galactic nuclei (AGN) produce copious amounts of high-energy emission, its origin has remained elusive. Using high-frequency radio interferometry (VLBI) polarization imaging, we could probe the magnetic field topology of the compact high-energy emission regions in blazars. A case study for the blazar 3C 279 reveals the presence of multiple g -ray emission regions. Pass 8 Fermi-Large Area Telescope (LAT) data are used to investigate the flux variations in the GeV regime; six g -ray flares were observed in the source during November 2013 to August 2014. We use the 43 GHz VLBI data to study the morphological changes in the jet. Ejection of a new component (NC2) during the first three g -ray flares suggests the VLBI core as the possible site of the high-energy emission. A delay between the last three flares and the ejection of a new component (NC3) indicates that highenergy emission in this case is located upstream of the 43 GHz core (closer to the black hole).Accepted manuscrip

Broad-band study of selected Gamma-ray active blazars

The analysis presented in this thesis is aimed to provide a more detailed understanding of the relation between flux density outbursts seen at radio, optical, and gamma-ray frequencies and the subsequent structural variability as seen by VLBI. Setting tighter observational constraints on parameters required for the synchrotron self-Compton and inverse-Compton modeling of the high-energy radiation is the prime target. A special attention is given to the parsec scale jet kinematics of the BL Lac object S5 0716+714 using mm-VLBI with an angular resolution up to ~50 microarcseconds. The aim of the broad-band variability study reported in this thesis is to provide a general physical scenario, which allows to put the observed variation of the source across several decades of frequencies in a coherent context. The densely sampled multi-frequency observations of S5 0716+714 over the past 5 years allow us to study its broad-band flaring behavior from radio to gamma-rays and probe into the physical processes, location and size of the emission regions for the source, which is ultra-compact and known to be one of the fastest variable blazars. The combination of the broad-band variability characteristics with the VLBI measurements provides new insights into the core region and at the jet base, a view which was not possible in earlier studies at lower VLBI observing frequencies. More explicitly, the correlation of the gamma-ray flaring activity with the emission at optical to radio frequencies is investigated focusing on some prominent flares observed between April 2007 and April 2012. The time evolution of radio (cm and mm) spectra is tested in the context of a standard shock-in-jet model. The broad-band spectral energy distribution (SED) of the source is investigated using a one-zone synchrotron self-Compton (SSC) model and also with a hybrid model, which involves a SSC and an external Compton (EC) component. The intense optical monitoring of the source reveals fast quasi-periodic variations superimposed on a long-term variability trend at a time scale of ~360 days. Episodes of fast variability recur on time scales of ~60-to-70 days. The prominent and simultaneous flaring activity at optical and gamma-ray frequencies favors the SSC mechanism for the production of the high-energy emission. The high-energy (gamma-ray - optical) flares propagate down to radio frequencies with a time delay of ~65 days following a power-law dependence in frequency with a slope ~0.3. This indicates that the internal opacity effects play a key role in producing time delays among light curves at optically thin and thick wavelengths. The evolution of the radio flares agrees with the formation of a shock and its propagation with a contribution of geometrical variation in addition to intrinsic variations in the jet. The broad-band spectral energy distributions (SEDs) of the source during different flaring episodes can not be well described by a pure one-zone SSC model, and require an additional EC contribution from the external radiation field, which is dominated by Ly-alpha emission from the broad-line region (BLR). A detailed investigation of the high-energy spectrum supports the view that the BLR has a significant impact on the observed gamma-ray spectral breaks at a few GeVs, due to pair production. The energy density of this external radiation field varies between 10-6 to 10-5,erg\,cm-3, which is a factor of ~1000 lower than what is expected for a typical quasar, and is a reasonable value for a gas poor (emission line-free) BL Lac object like S5 0716+714. High-frequency VLBI observations revealed a standing feature observed at ~0.1 milli-arcsecond separation from the core. Further downstream, the individual component motion indicates jet acceleration. Curved trajectories in the component motion, variations in the jet ridge line, and a position angle swing at the base of the jet are all consistent with the helical jet model, in which the ejected components transport angular momentum away from the central engine. The observed correlation of the core flux with the single dish radio flux light curves and the concurrent variations in the inner jet position angle with high-energy (optical/gamma-ray) flux suggests that the high-energy emission is coming from a region, which is located inside the mm-VLBI core, so upstream to the τ = 1 surface on scales <0.27 parsec towards the central black hole

Infection status of Clinostomum complanatum (Rudolphi, 1819) metacercaria from Channa punctatus of Meerut District

Metacercaria Clinostomum complanatum is a digenetic trematode, which is mainly found in fresh water fishes. Present communication deals with the infection status of C. complanatum in C. punctatus of Meerut district, which is supported by the data spreading over one year. About 250 specimens of C. punctatus from different ponds of Meerut were studied through regular periodical collection in the year Jan 2010 to Dec 2010. Overall prevalence 35.6%, mean intensity 3.06 and abundance 1.09 were reported. The infection was maximum in winter and minimum in rainy season. Prevalence, intensity and abundance of the infestation were also found to be related to different length group and sex of the hosts, the medium sized fishes were more infected and the larger size fishes were less infected while the smaller size fishes showed moderate infection. Susceptibility of infection was not significantly different between male and female fish

An Innovative Approach for Online Food Order Management System

Restaurants are one of the favorite premises. An online food ordering is a integrated process in fast food Restaurants to offer choice of food from menu, cooked and served or packaged hot to satisfy customer to immediately make orders on their ownselves. Customers can also call the restaurant to pack in advance or to deliver the food item but sometimes restaurants run out of certain items. The existing system lacks the feature to use Remote GPS tracker such that restaurant managers are auto updated about the location of the customer before reaching the restaurant. We propose a complete system to easily manage online menu where items update as per the availability of food and prices. The Customer views the products, register and place the order. The system administrator adds and manages user accounts and the Manager manages product and orders. The Kitchen meal deliverable deals with pending deliveries .The proposed system is developed using Android platform which is open source software and built in data connection modules. It also decreases labour rates to replace mobile phones to book order and table unlike employees who come to take order and payments .In advent of food consumption problems like obesity, overeating etc. ,he proposed system will show food items with nutrition based searches showing ingredients of the food items

Hysteroscopic salpingosonography: a novel technique for infertile patients

Background: Infertility is akin to curse in our country. Patients of infertility run from pillar to post to get relief. Government Hospitals in India lie at the tail end of window-shopping of infertility centres by the patients having exhausted all their resources. Patients report without any detailed records, lost reports, coming after long hiatus of having stopped treatment in desperation, making one wonder how to proceed. At the other end are patients who have undergone laparotomy for various reasons like intestinal obstruction, tubercular abdomen, adnexal masses and their tubal status is not very clear on HSG. So, repeat laparoscopy in the former group and performing ab initio in the latter, involves putting the patients to the risk of general anesthesia, injury to internal organs due to anticipated adhesions. Although Hassan’s technique of open trocar entry is well accepted the first port entry, whatever be the mode, is an entry open to risks.Methods: In a selected group of infertile women, a baseline TVS was done on 2/3 day of menses and on the 7/8 day of menstrual cycle hysteroscopy was done which was immediately followed by another transvaginal ultrasound. The descriptive statistics is presented in the form of percentages and appropriate graphs.Results: Among the 54 patients who underwent this procedure, 65% had normal uterine cavity. 18% were referred for IVF. 9.2% conceived post procedure.Conclusions: Successive use of transvaginal ultrasound after hysteroscopy i.e Hysteroscopic sonosalpingography is a useful procedure in a select group of infertile patients. 

Use of intrauterine balloon tamponade in successful conservative management of life threatening menorrhagia in a patient with idiopathic thrombocytopenic purpura and severe anemia

A 45-year-old woman was brought into the emergency ward of a tertiary care hospital. The patient gave a history of excess bleeding and passage of clots per vaginum since the past 15 days. The patient had a history of severe headaches, body ache, giddiness and vomiting. She was diagnosed with idiopathic thrombocytopenic purpura (ITP) and severe anemia six months before this incidence. The authors performed a diagnostic pelvic and transvaginal ultrasound and reported the presence of uterine fibroids. They determined that these fibroids had aggravated the bleeding which was caused by ITP. The diagnosis of ITP coupled with severe anemia prevented the authors from using the traditional approach of a hysterectomy in such a case. She was administered tranexamic acid, testosterone enanthate, blood, intravenous immunoglobulins, steroids and platelets transfusion. Uterine artery embolization (UAE) was tried for arresting menorrhagia, but was unsuccessful. Finally, a Bakri® balloon, normally used for management of post-partum hemorrhage (PPH), was inserted and retained for 48 hrs.. The bleeding gradually ceased and significant improvements in hematocrit and platelet count were observed. However, the patient then suffered from a deep vein thrombosis (DVT) in the lower extremity, which was treated with low molecular weight heparin (LMWH), a thrombectomy and an Inferior vena cava Filter. Patient was advised a hysterectomy to curb her symptoms, however, she was too exhausted of surgical procedures and refused. Therefore, the authors decided to employ the use of Selective Estrogen Receptor Molecule Therapy (SERM). 3-months post-intervention, patient is thriving and stable

Epidemiology and control strategies of novel coronavirus disease in the context of India

An outbreak of coronavirus disease (COVID-19) occurred for the first time in Wuhan, China which spread as a pandemic to various countries of the world, resulting in high morbidity and mortality. Death toll in India on 8th February 2021 was 1,55,080. India had implemented steps such as lockdown and advised social distancing, washing of hands, and wearing masks to reduce the burden of Covid-19. This review discusses the epidemiological features, the population at risk and control strategies of novel coronavirus disease in India. The data was collected from various sources on individual details of Covid-19 cases, population density and affluence percentage from the literature studied. The data was used to analyse the susceptibility of the population to this disease. It was found that Indian males, age group 20 to 40 (based on morbidity) and above 60 (based on mortality) were at high risk. The authors compiled epidemiology, management and control strategies of covid-19 in India. Therefore, because of various early implementations, India has managed the disease well earlier, but in the current scenario (30 Nov 2020) morbidity and mortality have been at peak. Immunization of frontline workers started on 16th January 2021. Initially, 7,017,411 doses of Covishield and Covaxin vaccines have been given by 10th February 2021. Thus, the existing strategies like proper diagnosis, treatment, and successful implementation of vaccine inoculation will reduce covid-19 burden and may lead to normalcy