scholarly journals Type IIn supernova light-curve properties measured from an untargeted survey sample

2020 ◽  
Vol 637 ◽  
pp. A73 ◽  
Author(s):  
A. Nyholm ◽  
J. Sollerman ◽  
L. Tartaglia ◽  
F. Taddia ◽  
C. Fremling ◽  
...  
Keyword(s):  
Light Curve ◽  
Template Matching ◽  
Statistical Significance ◽  
Absolute Magnitude ◽  
Late Time ◽  
Host Galaxies ◽  
Magnitude Distribution ◽  
Optical Light Curve ◽  
History Of ◽  
Survey Sample

The evolution of a Type IIn supernova (SN IIn) is governed by the interaction between the SN ejecta and a hydrogen-rich circumstellar medium. The SNe IIn thus allow us to probe the late-time mass-loss history of their progenitor stars. We present a sample of SNe IIn from the untargeted, magnitude-limited surveys of the Palomar Transient Factory (PTF) and its successor, the intermediate PTF (iPTF). To date, statistics on SN IIn optical light-curve properties have generally been based on small (≲10 SNe) samples from targeted SN surveys. The SNe IIn found and followed by the PTF/iPTF were used to select a sample of 42 events with useful constraints on the rise times as well as with available post-peak photometry. The sample SNe were discovered in 2009−2016 and have at least one low-resolution classification spectrum, as well as photometry from the P48 and P60 telescopes at Palomar Observatory. We study the light-curve properties of these SNe IIn using spline fits (for the peak and the declining portion) and template matching (for the rising portion). We study the peak-magnitude distribution, rise times, decline rates, colour evolution, host galaxies, and K-corrections of the SNe in our sample. We find that the typical rise times are divided into fast and slow risers at 20 ± 6 d and 50 ± 11 d, respectively. The decline rates are possibly divided into two clusters (with slopes 0.013 ± 0.006 mag d−1 and 0.040 ± 0.010 mag d−1), but this division has weak statistical significance. We find no significant correlation between the peak luminosity of SNe IIn and their rise times, but the more luminous SNe IIn are generally found to be more long-lasting. Slowly rising SNe IIn are generally found to decline slowly. The SNe in our sample were hosted by galaxies of absolute magnitude −22 ≲ Mg ≲ −13 mag. The K-corrections at light-curve peak of the SNe IIn in our sample are found to be within 0.2 mag for the observer’s frame r-band, for SNe at redshifts z <  0.25. By applying K-corrections and also including ostensibly “superluminous” SNe IIn, we find that the peak magnitudes are Mrpeak = −19.18 ± 1.32 mag. We conclude that the occurrence of conspicuous light-curve bumps in SNe IIn, such as in iPTF13z, are limited to 1.4+14.6−1.0 % of the SNe IIn. We also investigate a possible sub-type of SNe IIn with a fast rise to a ≳50 d plateau followed by a slow, linear decline.

scholarly journals AT 2019abn: multi-wavelength observations over the first 200 days

2020 ◽  
Vol 637 ◽  
pp. A20 ◽  
Author(s):  
S. C. Williams ◽  
D. Jones ◽  
P. Pessev ◽  
S. Geier ◽  
R. L. M. Corradi ◽  
...  
Keyword(s):  
Light Curve ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Absolute Magnitude ◽  
Low Velocity ◽  
Optical Telescope ◽  
Circumstellar Material ◽  
Medium Resolution ◽  
Multi Wavelength ◽  
Optical Light Curve

Context. AT 2019abn was discovered in the nearby M51 galaxy by the Zwicky Transient Facility at more than two magnitudes and around three weeks prior to its optical peak. Aims. We aim to conduct a detailed photometric and spectroscopic follow-up campaign for AT 2019abn, with early discovery allowing for significant pre-maximum observations of an intermediate luminosity red transient (ILRT) for the first time. Methods. This work is based on the analysis of u′BVr′i′z′H photometry and low-resolution spectroscopy using the Liverpool Telescope, medium-resolution spectroscopy with the Gran Telescopio Canarias (GTC), and near-infrared imaging with the GTC and the Nordic Optical Telescope. Results. We present the most detailed optical light curve of an ILRT to date, with multi-band photometry starting around three weeks before peak brightness. The transient peaked at an observed absolute magnitude of Mr′ = −13.1, although it is subject to significant reddening from dust in M51, implying an intrinsic Mr′ ∼ −15.2. The initial light curve showed a linear, achromatic rise in magnitude before becoming bluer at peak. After peak brightness, the transient gradually cooled. This is reflected in our spectra, which at later times show absorption from such species as Fe I, Ni I and Li I. A spectrum taken around peak brightness shows narrow, low-velocity absorption lines, which we interpret as likely to originate from pre-existing circumstellar material. Conclusions. We conclude that while there are some peculiarities, such as the radius evolution, AT 2019abn fits in well overall with the ILRT class of objects and is the most luminous member of the class seen to date.

scholarly journals Late-time observations of the extraordinary Type II supernova iPTF14hls

2019 ◽  
Vol 621 ◽  
pp. A30 ◽  
Author(s):  
J. Sollerman ◽  
F. Taddia ◽  
I. Arcavi ◽  
C. Fremling ◽  
C. Fransson ◽  
...  
Keyword(s):  
Light Curve ◽  
Late Time ◽  
Type Ii ◽  
Optical Photometry ◽  
Central Engine ◽  
Processed Material ◽  
Optical Light Curve ◽  
Steep Decline ◽  
The Many ◽  
Additional Space

Aims. We study iPTF14hls, a luminous and extraordinary long-lived Type II supernova, which lately has attracted much attention and disparate interpretation. Methods. We have presented new optical photometry that extends the light curves up to more than three years past discovery. We also obtained optical spectroscopy over this period, and furthermore present additional space-based observations using Swift and HST. Results. After an almost constant luminosity for hundreds of days, the later light curve of iPTF14hls finally fades and then displays a dramatic drop after about 1000 d, but the supernova is still visible at the latest epochs presented. The spectra have finally turned nebular, and our very last optical spectrum likely displays signatures from the deep and dense interior of the explosion. A high-resolution HST image highlights the complex environment of the explosion in this low-luminosity galaxy. Conclusions. We provide a large number of additional late-time observations of iPTF14hls, which are (and will continue to be) used to assess the many different interpretations for this intriguing object. In particular, the very late (+1000 d) steep decline of the optical light curve is difficult to reconcile with the proposed central engine models. The lack of very strong X-ray emission, and the emergence of intermediate-width emission lines including [S II] that we propose originate from dense, processed material in the core of the supernova ejecta, are also key observational tests for both existing and future models.

Gene mutation and drug resistance of M. tuberculosis in the patients followed up in the city of Moscow

2020 ◽  
Vol 97 (12) ◽  
pp. 34-44
Author(s):  
M. A. Krasnova ◽  
E. M. Belilovsky ◽  
S. E. Borisov ◽  
A. A. Khakhalina ◽  
Yu. D. Mikhaylova ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Statistical Significance ◽  
Molecular Genetic ◽  
Previous Treatment ◽  
Repeated Treatment ◽  
Phenotypic Resistance ◽  
Therapy Regimen ◽  
Treatment History ◽  
History Of ◽  
Relationship Of

The article describes a retrospective study of the results of microbiological and molecular genetic tests of 685 M. tuberculosis cultures isolated from 685 adult tuberculosis patients registered for dispensary follow-up in Moscow in 2014.The following was identified during the study: phenotypic drug resistance (FDR) of MTB to rifampicin, isoniazid, fluoroquinolones, kanamycin, amikacin, and capreomycin in groups of patients with different treatment history; the frequency of FDR to the above anti-tuberculosis drugs in strains with mutations being drug resistance markers; the frequency of various mutations in case of FDR of mycobacteria in the patients from different groups; the relationship of FDR or the presence of a particular mutation with various characteristics of the patients and their treatment history.The history of previous treatment was determined as statistical significance to provide the greatest influence on the spread of drug resistant MTB: patients undergoing repeated treatment had FDR more often and also a much more pronounced variety of mutations being markers of FDR to certain anti-tuberculosis drugs.The results of the study showed that the detection of genetic mutations in MBT associated with FDR was a reliable tool for predicting phenotypic resistance and should be used as the main method for selecting anti-tuberculosis drugs when compiling the etiotropic therapy regimen.

Optical Light Curve of the Type I[CLC]a[/CLC] Supernova 1998[CLC]bu[/CLC] in M96 and the Supernova Calibration of the Hubble Constant

1999 ◽  
Vol 117 (3) ◽  
pp. 1175-1184 ◽  
Author(s):  
Nicholas B. Suntzeff ◽  
M. M. Phillips ◽  
R. Covarrubias ◽  
M. Navarrete ◽  
J. J. Pérez ◽  
...  
Keyword(s):  
Light Curve ◽  
Hubble Constant ◽  
Type I ◽  
Optical Light Curve

scholarly journals Melanoma is associated with an increased risk of bullous pemphigoid: a large population-based longitudinal study

2021 ◽  
Author(s):  
Khalaf Kridin ◽  
Jennifer E. Hundt ◽  
Ralf J. Ludwig ◽  
Kyle T. Amber ◽  
Dana Tzur Bitan ◽  
...  
Keyword(s):  
Bullous Pemphigoid ◽  
Statistical Significance ◽  
Large Population ◽  
Underlying Mechanism ◽  
Population Based ◽  
Control Subjects ◽  
Increased Risk ◽  
Bidirectional Association ◽  
History Of ◽  
Incident Cases

AbstractThe association between bullous pemphigoid (BP) and melanoma is yet to be investigated. We aimed to assess assess the bidirectional association between BP and melanoma and to delineate the epidemiological features of patients with both diagnoses. A population-based cohort study was performed comparing BP patients (n = 3924) with age-, sex- and ethnicity-matched control subjects (n = 19,280) with regard to incident cases of melanoma. A case–control design was additionally adopted to estimate the risk of BP in individuals with a preexisting diagnosis of melanoma. The prevalence of preexisting melanoma was higher in patients with BP than in control subjects (1.5% vs. 1.0%, respectively; P = 0.004). A history of melanoma confers a 50% increase in the risk of subsequent BP (OR 1.53; 95% CI 1.14–2.06). This risk was higher among males (OR 1.66; 95% CI 1.09–2.54) and individuals older than 80 years (OR 1.63; 95% CI 1.11–2.38), and persisted after adjustment for multiple putative confounders including PD-1/PDL-1 antagonists (adjusted OR 1.53; 95% CI 1.14–2.06). Conversely, the risk of melanoma among patients with BP was slightly elevated, but did not reach the level of statistical significance (adjusted HR 1.13; 95% CI 0.73–1.74). Patients with a dual diagnosis of BP and melanoma were older at the onset of BP and had lower body mass index. A history of melanoma is associated with a 50% increase in the incidence of subsequent BP. Physicians managing patients with both conditions should be aware of this association. Further research is warranted to reveal the underlying mechanism of these findings.

Violence committed and victimization in courtship in adolescents: Does gender matter?

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
E A Villegas Vázquez ◽  
J C Leyva Chipol ◽  
K C Cervantes Gómez ◽  
S I Valencia Almeida ◽  
F G Márquez Celedonio ◽  
...  
Keyword(s):  
High School Students ◽  
Sexual Violence ◽  
Mental Health Problems ◽  
Physical Violence ◽  
Statistical Significance ◽  
Research Question ◽  
Middle Level ◽  
School Students ◽  
History Of ◽  
Del Rio

Abstract Introduction Within the current context in our Mexico, major states of violence for women have been manifested on a daily basis without having any more reason than being female. Veracruz is the first place in feminicides in Mexico with a rate of 3.44 per 100 thousand women. Research question: What is the intensity of the violence committed and victimization in the courtship of young students of the Upper Middle level in the Veracruz - Boca del Río area, according to their gender? Material and Methods A cross-sectional, prospective, observational and analytical study was carried out from December to February 2020. Middle-high school students from the Veracruz-Boca del Río region were included, who had a dating relationship and were excluded those who did not accept to participate. The variable “violence committed and victimization in courtship” was quantified with the CADRI instrument. The spss v22 software was used, Sudent's T was calculated for independent samples, with statistical significance p &lt; 0.05. Results 741 students were included. There was a prevalence of violence committed of 86.2% and victimization of 89.2%. Of the total number of students who suffered and committed violence, women occupy 66.3% and 66.7% respectively. There is a difference in the intensity of violence between women and men in verbal-emotional violence (4.5 ± 4.2 vs. 3.4 ± 3.4), physical violence (0.6 ± 1.3 vs. 0.36 ± 3.6) and violence in general (5.7 ± 5.7 vs 4.3 ± 4.8) (p &lt; 0.05), while victimization scores do not make a difference between both genders (p &gt; 0.05). The history of psychological and sexual violence in previous relationships, as well as sexual violence in daily life are more frequent in the female sex (p &lt; 0.05) Conclusions The violence generated is more intense in women, however, they also have a history of having suffered violence more frequently in previous relationships and in their daily lives. Key messages Women suffer more aggressions at different stages of their lives, which may increase the risk to tolerate aggressions or be more aggressive or suffer mental health problems. We must study if the violence generated by women is a response to a previous aggression from their boyfriend.

scholarly journals A pre-outburst signal in the long-term optical light curve of the recurrent nova RS Ophiuchi

2011 ◽  
Vol 414 (3) ◽  
pp. 2195-2203 ◽  
Author(s):  
S. Adamakis ◽  
S. P. S. Eyres ◽  
A. Sarkar ◽  
R. W. Walsh
Keyword(s):  
Light Curve ◽  
Optical Light Curve ◽  
Recurrent Nova

Amelogenesis Imperfecta Prevalence in a Colombian Population: A Retrospective Study

2021 ◽  
Vol 40 ◽  
Author(s):  
Lizeth Paola Naranjo Jiménez ◽  
Myriam Adriana Muñoz Briceño ◽  
Ángela Suárez Castillo ◽  
Claudia Patricia Lamby Tovar ◽  
Sandra Janeth Gutierrez Prieto
Keyword(s):  
Urban Areas ◽  
Tooth Enamel ◽  
Amelogenesis Imperfecta ◽  
Cross Sectional ◽  
Prevalence Studies ◽  
Magnitude Distribution ◽  
Preventive Actions ◽  
History Of ◽  
And Behavior ◽  
Frequency Magnitude Distribution

Background: Amelogenesis imperfecta (AI) is a hereditary condition that affects the structure of tooth enamel and causes sensitivity, predisposition to cavities, and psychological problems. In Colombia, its frequency, magnitude, distribution, and behavior are unknown, so it is necessary to carry out prevalence studies to implement preventive actions. Purpose: To determine the prevalence of AI in patients who have attended the Pontificia Universidad Javeriana clinics in Bogotá. Methods: A retrospective cross-sectional observational study was carried out, whose sample included 1,394 medical records of patients who attended between January 2015 and December 2017. Results: The prevalence of AI was 0.6 %, corresponding to 8 people affected, 4 men and 4 women between the ages of 9 and 10 years. The most frequent phenotype was hypoplastic in 7 patients (87.5 %) and one person had a hypocalcified phenotype (12.5 %). Taurodontism was the most frequent anomaly in the 8 patients (100 %). Seven of the eight patients (87.5 %) had a family history of AI. All the individuals had a lower-middle socioeconomic level and came from urban areas. Conclusions: This study is the first approximation to determine the prevalence of AI in a group of the Colombian population. Although the prevalence was low, it is comparable with the findings of other studies.

scholarly journals HEMOGLOBIN STATUS OF FEMALE MEDICOS IN URBAN AREA AND FACTORS AFFECTING IT: AN OBSERVATIONAL CROSS-SECTIONAL STUDY

2017 ◽  
Vol 10 (3) ◽  
pp. 439
Author(s):  
Drpadmajauday Kumar ◽  
Varsha Kalyanpur
Keyword(s):  
Statistical Significance ◽  
Cross Sectional Study ◽  
Leafy Vegetables ◽  
Sectional Study ◽  
Cross Sectional ◽  
Factors Affecting ◽  
Green Leafy Vegetables ◽  
Nutritional Anemia ◽  
Mild Anemia ◽  
History Of

ABSTRACTObjectives: Estimating the hemoglobin (Hb) status in female medicos through prospective cross-sectional study and assessment of influencing ofcofactors were objectives.Methods: Women medicos who volunteered, consented and met selection criteria were enrolled. Hb level was estimated to diagnose anemia.Relationship with influencing factors was assessed statistically.Result: A total of 100 eligible students were enrolled. Mean age±standard deviation (SD) age of the participants’ was 20.9±3.1 years (17-25 years).Mean±SD Hb was 12.25±1.0189 g% (9.0-16.0 g%). 33 were anemic, and mild anemia (32%) was frequent. There was a history of worm infestation inthree students (3%), who were treated adequately. Nine were on iron supplements of which five were still anemic and were continuing the treatmentby the end of the study. 28 (84.84%) anemic students were not on any iron or hematinic treatment. There was no association between the anemiaand nature of diet, consumption of green leafy vegetables, consumption of coffee/tea after food, smoking/tobacco or alcohol consumption, mother’seducation, socioeconomic status, menstrual factors, and physical exercise. The prevalence of anemia was found to be higher in underweight andoverweight students in comparison to students with normal body mass index.Asymptomatic participants (n=78) outnumbered symptomatic ones(n=22), but without any statistical significance. Easy fatigability (14%), pallor (7%), breathlessness (6%), weakness (9%), and easy bruising (1%)were frequent complaints.Conclusion: Anemia is frequent among women medicos, often underdiagnosed, under-reported, many remaining asymptomatic. Negligence ofmedical students toward their anemic status despite the awareness of consequences of low Hb level is a serious cause of concern.Keywords: Awareness, Hemoglobin, Nutritional anemia, Women medical students.

scholarly journals Constraints on the density distribution of type Ia supernovae ejecta inferred from late-time light-curve flattening

2020 ◽  
Vol 493 (4) ◽  
pp. 5617-5624
Author(s):  
Doron Kushnir ◽  
Eli Waxman
Keyword(s):  
Light Curve ◽  
Weighted Average ◽  
Far Infrared ◽  
Average Density ◽  
Light Curves ◽  
Type Ia Supernovae ◽  
Late Time ◽  
Simple Method ◽  
Type Ia ◽  
Ia Supernovae

ABSTRACT The finite time, τdep, over which positrons from β+ decays of 56Co deposit energy in type Ia supernovae ejecta lead, in case the positrons are trapped, to a slower decay of the bolometric luminosity compared to an exponential decline. Significant light-curve flattening is obtained when the ejecta density drops below the value for which τdep equals the 56Co lifetime. We provide a simple method to accurately describe this ‘delayed deposition’ effect, which is straightforward to use for analysis of observed light curves. We find that the ejecta heating is dominated by delayed deposition typically from 600 to 1200 d, and only later by longer lived isotopes 57Co and 55Fe decay (assuming solar abundance). For the relatively narrow 56Ni velocity distributions of commonly studied explosion models, the modification of the light curve depends mainly on the 56Ni mass-weighted average density, 〈ρ〉t3. Accurate late-time bolometric light curves, which may be obtained with JWST far-infrared (far-IR) measurements, will thus enable to discriminate between explosion models by determining 〈ρ〉t3 (and the 57Co and 55Fe abundances). The flattening of light curves inferred from recent observations, which is uncertain due to the lack of far-IR data, is readily explained by delayed deposition in models with $\langle \rho \rangle t^{3} \approx 0.2\, \mathrm{M}_{\odot }\, (10^{4}\, \textrm{km}\, \textrm{s}^{-1})^{-3}$, and does not imply supersolar 57Co and 55Fe abundances.

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