Accretion in the recurrent nova T CrB: Linking the superactive state to the predicted outburst

Context: T CrB (NOVA CrB 1946) is a famous recurrent nova with a recurrence timescale of 80 years. Aims: We aim to estimate the colours, luminosity, and mass-accretion rate for T CrB (NOVA CrB 1946) during and after the superactive state. Methods and Results: We performed and analysed $UBV$ photometry of the recurrent nova T~CrB. For the hot component of T~CrB, we find average dereddened colours of $(U-B)_0 = -0.70 \pm 0.08$ and $(B-V)_0 = 0.23 \pm 0.06$, which correspond to an effective temperature of $9400 \pm 500$~K and an optical luminosity of $40-110~L_\odot$ during the superactive state (2016-2022). After the end of the superactive state, the hot component became significantly redder, $(U-B)_0 \approx -0.3$ and $(B-V)_0 \approx 0.6$ in August 2023, and its luminosity decreased markedly to $20-25$~$L_\odot$ in April-May 2023, and to $8-9~L_\odot$ in August 2023. The total mass accreted during the superactive state from 2014 to 2023 is $\sim 2 \times 10^{-7}$~M$_\odot$. This is a significant fraction of the mass required to cause a thermonuclear runaway (TNR). Overall our results support a model in which a large accretion disc acts as a reservoir with increased accretion rate onto the central white dwarf during disc high states, ultimately leading to a TNR explosion, which now seems to be imminent.Comment: Astronomy & Astrophysics (accepted

Pre-outburst signal in the light curves of the recurrent novae RS Oph and T CrB

Pre-outburst signal (a decrease of the optical brightness) just before the outburst is clearly detected in the observations of the T CrB obtained before and during the 1946 outburst. A similar decrease is also visible in the light curve of RS Oph during the 2021 outburst. We suppose that this is due to formation of a thick, dense envelope around the white dwarf, and we estimate its size (1000 - 2000 km), mass (5.10$^{-8}$ - 6.10$^{-7}$ M$_\odot$) and average density (5 - 16 g cm$^{-3}$).Comment: preliminary versio

Narrowband, mid-infrared, seeded optical parametric generator based on non-critical CdSiP2 pumped by 120-ps, single longitudinal mode 1,064 nm pulses

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The hidden symbiotic star SU Lyn-detection of flickering in U band

We report photometric observations of the hidden symbiotic star SU Lyn in the optical bands. In four nights we detect a weak flickering in U band with amplitude of about 0.05 magnitudes. No intranight variations are found in B, V, g’ and r’ bands. This is one more indication that the secondary component is a white dwarf accreting at a low accretion rate Ẇe also searched for intranight variability of a dozen related objects-RR Boo, RT Boo, AM Cyg, AG Peg, BF Cyg, NQ Gem, StHa190, V627 Cas, XX Oph, FS Cet and Y Gem-however no variability above the observational errors is detected

Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF

M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe

Baseline characteristics of patients in the reduction of events with darbepoetin alfa in heart failure trial (RED-HF)

<p>Aims: This report describes the baseline characteristics of patients in the Reduction of Events with Darbepoetin alfa in Heart Failure trial (RED-HF) which is testing the hypothesis that anaemia correction with darbepoetin alfa will reduce the composite endpoint of death from any cause or hospital admission for worsening heart failure, and improve other outcomes.</p> <p>Methods and results: Key demographic, clinical, and laboratory findings, along with baseline treatment, are reported and compared with those of patients in other recent clinical trials in heart failure. Compared with other recent trials, RED-HF enrolled more elderly [mean age 70 (SD 11.4) years], female (41%), and black (9%) patients. RED-HF patients more often had diabetes (46%) and renal impairment (72% had an estimated glomerular filtration rate <60 mL/min/1.73 m2). Patients in RED-HF had heart failure of longer duration [5.3 (5.4) years], worse NYHA class (35% II, 63% III, and 2% IV), and more signs of congestion. Mean EF was 30% (6.8%). RED-HF patients were well treated at randomization, and pharmacological therapy at baseline was broadly similar to that of other recent trials, taking account of study-specific inclusion/exclusion criteria. Median (interquartile range) haemoglobin at baseline was 112 (106–117) g/L.</p> <p>Conclusion: The anaemic patients enrolled in RED-HF were older, moderately to markedly symptomatic, and had extensive co-morbidity.</p&gt

1064 nm pumped CdSiP2 optical parametric oscillator generating sub-300 ps pulses near 6.15 µm at 1-10 kHz repetition rates

Here we present a short cavity singly resonant optical parametric oscillator (OPO) emitting ~400 ps pulses in the interesting for medical applications wavelength region near 6.1 μm which is not accessible by oxide based nonlinear materials

Evaluation of Polyphenols Synthesized in Mature Seeds of Common Bean (<i>Phaseolus vulgaris</i> L.) Advanced Mutant Lines

This study aimed to investigate the availability of flavonoids, anthocyanins, and phenolic acids in mutant bean seeds, focusing on M7 mutant lines, and their corresponding initial and local cultivars. HPLC-DAD-MS/MS and HPLC-MS/MS were used to analyze twenty-eight genotypes of common bean. The obtained results suggest that the mutations resulted in four newly synthesized anthocyanins in the mutant bean seeds, namely, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside, pelargonidin 3-O-glucoside, and petunidin 3-O-glucoside, in 20 accessions with colored seed shapes out of the total of 28. Importantly, the initial cultivar with white seeds, as well as the mutant white seeds, did not contain anthocyanins. The mutant lines were classified into groups based on their colors as novel qualitative characteristics. Five phenolic acids were further quantified: ferulic, p-coumaric, caffeic, sinapic, and traces of chlorogenic acids. Flavonoids were represented by epicatechin, quercetin, and luteolin, and their concentrations in the mutant genotypes were several-fold superior compared to those of the initial cultivar. All mutant lines exhibited higher concentrations of phenolic acids and flavonoids. These findings contribute to the understanding of the genetics and biochemistry of phenolic accumulation and anthocyanin production in common bean seeds, which is relevant to health benefits and might have implications for common bean breeding programs and food security efforts