926 research outputs found
Decoding NGC 7252 as a blue elliptical galaxy
Elliptical galaxies with blue optical colours and significant star formation
are hypothesised to be major merger remnants of gas-rich spiral galaxies or
normal elliptical galaxies with a sudden burst of star formation. We present
here a scenario in which blue elliptical galaxies identified in shallow imaging
surveys may fail to recover faint features that are indicative of past merger
activity using a nearby major merger remnant. Based on deep optical imaging
data of the post-merger galaxy, NGC 7252, we demonstrate that the galaxy can
appear as an elliptical galaxy if it is observed at higher redshifts. The main
body and the low surface brightness merger features found at the outskirts of
the galaxy are blue in the optical g - r colour map. We argue that the
higher-redshift blue elliptical galaxies discovered in surveys as shallow as
the SDSS or DECaLS may be advanced mergers whose defining tidal features fall
below the detection limits of the surveys. This should be taken into
consideration during the morphological classification of these systems in
future and ongoing surveys.Comment: Accepted for publication in A&
Deep optical imaging of star-forming blue early-type galaxies: Color map structures and faint features indicative of recent mergers
Blue early-type galaxies with galaxy-scale ongoing star formation are
interesting targets in order to understand the stellar mass buildup in
elliptical and S0 galaxies in the local Universe. We study the star-forming
population of blue early-type galaxies to understand the origin of star
formation in these otherwise red and dead stellar systems. The legacy survey
imaging data taken with the dark energy camera in the , , and bands
for 55 star-forming blue early-type galaxies were examined, and color
maps were created. We identified low surface brightness features near 37
galaxies, faint-level interaction signatures near 15 galaxies, and structures
indicative of recent merger activity in the optical color maps of all 55
galaxies. These features are not visible in the shallow Sloan Digital Sky
Survey imaging data in which these galaxies were originally identified. Low
surface brightness features found around galaxies could be remnants of recent
merger events. The star-forming population of blue early-type galaxies could be
post-merger systems that are expected to be the pathway for the formation of
elliptical galaxies. We hypothesize that the star-forming population of blue
early-type galaxies is a stage in the evolution of early-type galaxies. The
merger features will eventually disappear, fuel for star formation will cease,
and the galaxy will move to the passive population of normal early-type
galaxies.Comment: Accepted in A&
Descriptive study of gastrointestinal manifestations in HIV/AIDS
Background: Acquired Immunodeficiency Syndrome (AIDS) was first recognized in 1981 as a clinical syndrome consisting of opportunistic infections and /or neoplasia associated with uneplained immunodeficiency. The gastrointestinal tract is one of the most common sites of clinical affection of AIDS and all levels from the oral cavity to the anus are frequently involved.Methods: A cohort of 70 HIV positive patients, admitted in a tertiary level referral hospital, were studied for symptoms of gastrointestinal disease and patients with clinical or investigative findings of gastrointestinal disease were clinically examined and then subjected to further relevant investigations.Results: The prevalence of GI menifestations in this cohort was 71.4%. The mean age of the study population was 36 years. Amongst frequency of GI manifestations, diarrhoea was found in 26 patients (52%), of whom 77% (20 out of 26) had diarrhoea lasting longer than one month and amongst the patients with oral ulcers, oral candidiasis was the most common oral manifestation, present in 87% of them. Cryptosporidium was the most common organism isolated from the stool samples.Conclusions: The most common presenting complaints were oral ulcers and chronic diarrhoea amongst the cohort examined in this study
A late, infrared flash from the afterglow of GRB 050319
We report the detection of a bright, near-infrared flash from the afterglow
of GRB 050319, 6.15 hours after the burst. The IR flash faded rapidly from
J=13.12 mag. to J > 15.5 mag. in about 4 minutes. There are no reported
simultaneous observations at other wavelengths making it an unique event. We
study the implications of its late timing in the context of current theoretical
models for GRB afterglows.Comment: Accepted in ApJ (Letters
A study to assess the knowledge and attitude of female graduate students on cervical cancer
Background: Cervical cancer is one of the most common cancers in women with an average of 468,000 new cases per year. Out of these 80% occur in developing and underdeveloped countries. World Health Organisation statistics show that Indian carries one fifths of world burden of the disease with 72,600 deaths annually. Key to the success of cervical cancer screening and prevention is the knowledge and awareness possessed by women in general. This requires the honing of knowledge at an impressionable and younger age group.Methods: It is a questionnaire based cross sectional study and was conducted amongst 4 study groups comprising Medical students, engineering students, nursing students and general graduate students between the age group 18 and 25 years.Results: According to present study, 93% of medical, 75% of nursing and only 29% of engineering students and 9 % of other students were actually even aware of the term cervical cancer. Assessment of knowledge regarding the risk factors of cervical cancer revealed that 13 medical, 9 nursing, 75 of engineering and 85 of Other Graduates weren’t aware of any risk factor that causes cervical cancer. As regards to attitude of the students towards cancer, present study revealed 4 medical, 23 nursing, 10 engineering and 9 general public women think that it is incurable and leads to death.Conclusions: This study highlights unawareness of various aspects of cervical cancer among young women and the burning need for continuing educational intervention at institute level to emphasise the importance and increase the awareness regarding cervical cancer
Sentinel Lymph Node Biopsy : A new approach in the management of head and neck cancers
Cervical lymph node metastasis affects the prognosis and overall survival rate of and therapeutic planning for patients with head and neck squamous cell carcinomas (HNSCCs). However, advanced diagnostic modalities still lack accuracy in detecting occult neck metastasis. A sentinel lymph node biopsy is a minimally invasive auxiliary method for assessing the presence of occult metastatic disease in a patient with a clinically negative neck. This technique increases the specificity of neck dissection and thus reduces morbidity among oral cancer patients. The removal of sentinel nodes and dissection of the levels between the primary tumour and the sentinel node or the irradiation of target nodal basins is favoured as a selective treatment approach; this technique has the potential to become the new standard of care for patients with HNSCCs. This article presents an update on clinical applications and novel developments in this field.
The incidence and clinical profile of dengue hemorrhagic fever among patients diagnosed with dengue fever in a tertiary care centre in south India
Background: An understanding of factors predictive of severe forms of dengue fever would be helpful in risk stratification. The objective of the study was to determine incidence of and the factors associated with the development of dengue hemorrhagic fever (DHF) among patients admitted with dengue fever.Methods: Consenting patients were consecutively enrolled in the study and were followed forward in time to establish if they had DHF rather than milder dengue. Several factors were studied to ascertain their relation to conversion to DHF.Results: Cases included were 160 (103 males), with a mean age of 39.4 years (age range: 13-78). Fifty one (32%) developed DHF. On multivariate analysis; hepatomegaly, high alanine transaminase, low serum albumin and systolic blood pressure ≤100 mm Hg were independent predictors for the development of DHF.Conclusions: Nearly a third of patients with dengue fever develop DHF. The predictors identified, should alert the physician to this impending complication.
- …