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2022 ◽  
Vol 924 (1) ◽  
pp. 35
Author(s):  
Liping Li ◽  
Jujia Zhang ◽  
Benzhong Dai ◽  
Wenxiong Li ◽  
Xiaofeng Wang ◽  
...  

Abstract We present optical and ultraviolet (UV) observations of a luminous type Ia supernova (SN Ia) SN 2015bq characterized by early flux excess. This SN reaches a B-band absolute magnitude at M B = −19.68 ± 0.41 mag and a peak bolometric luminosity at L = (1.75 ± 0.37) × 1043 erg s−1, with a relatively small post-maximum decline rate [Δm 15(B) = 0.82 ± 0.05 mag]. The flux excess observed in the light curves of SN 2015bq a few days after the explosion, especially seen in the UV bands, might be due to the radioactive decay of 56Ni mixed into the surface. The radiation from the decay of the surface 56Ni heats the outer layer of this SN. It produces blue U − B color followed by monotonically reddening in the early phase, dominated iron-group lines, and weak intermediate-mass element absorption features in the early spectra. The scenario of enhanced 56Ni in the surface is consistent with a large amount of 56Ni ( M 56 Ni = 0.97 ± 0.20 M ☉) synthesized during the explosion. The properties of SN 2015bq are found to locate between SN 1991T and SN 1999aa, suggesting the latter two subclasses of SNe Ia may have a common origin.


Author(s):  
Satish Kumar

Introduction: Anemia is the commonest major contributing factor in maternal mortality and morbidity in developing countries and according to World Health Organization (WHO) criteria, it contributes to 20% of maternal deaths. Anemia in pregnancy defined as hemoglobin level <11 gm/dl (7.45 mmol/L) and hematocrit less than 33% (WHO). Aim: To compare the efficacy of oral iron ferrous sulphate therapy with intravenous iron sucrose therapy in the treatment of iron deficiency anemia during postpartum period. Material & Methods: This was a prospective randomized comparative clinical trial single center study conducted on 200 postpartum women aged >18 years (after normal delivery or LSCS) within 10 days of delivery with Hb level more or equal to 6 gm/dl but less than 10 gm/dl were included in the study. This was a one year study conducted during 1st December 2018 to 30th November 2019. Results : There was a significant increase in the hemoglobin level in both the groups i.e. in IV iron group, from 8.26 ±1.03gm/dl on day 1 to 11.62±0.94gm/dl on day 45 as compared to oral iron group, from 8.24±1.09gm/dl on day 1 to 11.07±1.14gm/dl on day 45; and serum ferritin level from 41.69±40.45ng/ml on day 1 to 77.34±41.60ng/ml on day 45 in IV iron group as compared to the oral iron group from 22.20±8.82ng/ml on day 1 to 31.72±9.72 ng/ml on day 45. So, there was a rapid increase in both hemoglobin and serum ferritin levels in IV iron group as compared to the oral iron group. Conclusion: Intravenous iron sucrose administration increases the hemoglobin level and serum ferritin more rapidly in compare to the oral intake of ferrous sulphate in women with iron deficiency anemia in postpartum women in our study. Keywords: Iron deficiency anemia, Intravenous iron sucrose, Serum ferritin, Maternal mortality.


Universe ◽  
2021 ◽  
Vol 7 (12) ◽  
pp. 487
Author(s):  
Vladimir N. Kondratyev

Nucleosynthesis at latge magnetic induction levels relevant to core-collapse supernovae and neutron star mergers is considered. For respective magnetic fields of a strength up to ten teratesla, atomic nuclei exhibit a linear magnetic response due to the Zeeman effect. Such nuclear reactivity can be described in terms of magnetic susceptibility. Susceptibility maxima correspond to half-filled shells. The neutron component rises linearly with increasing shell angular momentum, while the contribution of protons grows quadratically due to considerable income from orbital magnetization. For a case j = l + 1/2, the proton contribution makes tens of nuclear magnetons and significantly exceeds the neutron values which give several units. In a case j = l − 1/2, the proton component is almost zero up to the g shell. A noticeable increase in the generation of corresponding explosive nucleosynthetic products with antimagic numbers is predicted for nuclei at charge freezing conditions. In the iron group region, new seeds are also created for the r-process. In particular, the magnetic enhancement of the volume of 44Ti isotopes is consistent with results from observations and indicates the substantial increase in the abundance of the main titanium isotope (48Ti) in the Galaxy’s chemical composition. Magnetic effects are proven to result in a shift of the r-process path towards smaller mass numbers, as well as an increase in the volume of low-mass nuclides in peaks of the r-process nuclei.


2021 ◽  
Vol 21 (11) ◽  
pp. 287
Author(s):  
Jing-Jing Liu ◽  
Dong-Mei Liu

Abstract Using the theory of relativistic mean-field effective interactions, the influences of superstrong magnetic fields (SMFs) on electron Fermi energy, binding energy per nucleus and single-particle level structure are discussed in super-Chandrasekhar magnetic white dwarfs. Based on the relativistical SMFs theory model of Potekhin et al., the electron chemical potential is corrected in SMFs, and the electron capture (EC) of iron group nuclei is investigated by using the Shell-Model Monte Carlo method and Random Phase Approximation theory. The EC rates can increase by more than three orders of magnitude due to the increase of the electron Fermi energy and the change of single-particle level structure by SMFs. However, the EC rates can decrease by more than four orders of magnitude due to increase of the nuclei binding energy by SMFs. We compare our results with those of FFNs (Fuller et al.), AUFDs (Aufderheide et al.) and Nabi (Nabi et al.). Our rates are higher by about four orders of magnitude than those of FFN, AUFD and Nabi due to SMFs. Our study may have important reference value for subsequent studies of the instability, mass radius relationship, and thermal and magnetic evolution of super-Chandrasekhar magnetic white dwarfs.


2021 ◽  
Vol 43 ◽  
pp. 42-52
Author(s):  
Yanli Niu ◽  
Xue Teng ◽  
Shuaiqi Gong ◽  
Xuan Liu ◽  
Mingze Xu ◽  
...  

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3076-3076
Author(s):  
Rebecka Hansen ◽  
Joergen Kurtzhals ◽  
Bjarne Styrishave ◽  
Charlotte Holm

Abstract Introduction: Hepcidin, the master regulator of iron economy, is decreased during pregnancy to facilitate adequate iron transfer across the placenta. Conversely, iron need increases substantially during pregnancy often leading to iron deficiency and subsequently anemia. The PREG-01 Study compared the efficacy and safety of intravenous (IV) ferric derisomaltose (FDI) vs. oral iron in treating persistent iron deficiency in pregnant women. The study found FDI to be efficacious and well-tolerated in pregnancy and the proportion of non-anaemic patients throughout the course of the study was significantly lower in the FDI group. In this analysis, we investigated the effect of baseline hepcidin on the response to IV and oral iron therapy. Methods: PREG-01 was a single-centre, open-label, randomized controlled trial. Women 14-21 weeks pregnant with persistent iron deficiency (ferritin&lt;30 µg/L despite oral iron treatment) received a single intravenous 1000 mg dose of FDI (n=100) or 100 mg elemental oral iron daily combined with ascorbic acid (n=101). Hemoglobin (Hb), ferritin and transferrin saturation (TSAT%) levels were captured at baseline and monitored throughout the study. The effect of baseline hepcidin on achieving non-anemic status (Hb ≥ 11 g/dL) at all study visits and the effect on change in Hb, ferritin and TSAT% were investigated by estimating odds ratios from a logistic regression model with treatment as factor and interaction between treatment and baseline hepcidin. The odds ratio estimate is for an increment in baseline hepcidin of 1 ng/mL. Results: Mean [standard deviation (SD)] baseline Hb was 11.97 (0.93) g/dL in the FDI group and 11.75 (0.91) g/dL in the oral iron group. Baseline hepcidin was 6.42 ng/mL in the FDI and 5.32 ng/mL in the oral iron group. Baseline hepcidin was not associated with the ability to achieve non-anaemic status either in the FDI (OR 0.98; 95% CI: 0.87-1.09) or the oral iron group (OR 0.96; 95% CI: 0.88-1.05). No statistically significant associations were found between baseline hepcidin and change in Hb, ferritin or TSAT% throughout the study (Figure 1). Conclusions: In a population of pregnant women with iron deficiency, but otherwise healthy, baseline hepcidin was overall low. Although there was a trend for an association between baseline hepcidin and Hb response to oral iron only, baseline hepcidin did not predict the response to iron therapy. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare. OffLabel Disclosure: Ferric Derisomaltose is an IV iron preparation indicated for the treatment of iron deficiency anemia in the US.


Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5824
Author(s):  
Emil Babić ◽  
Đuro Drobac ◽  
Ignacio Alejandro Figueroa ◽  
Mathilde Laurent-Brocq ◽  
Željko Marohnić ◽  
...  

The study of the transition from high-entropy alloys (HEAs) to conventional alloys (CAs) composed of the same alloying components is apparently important, both for understanding the formation of HEAs and for proper evaluation of their potential with respect to that of the corresponding CAs. However, this transition has thus far been studied in only two types of alloy systems: crystalline alloys of iron group metals (such as the Cantor alloy and its derivatives) and both amorphous (a-) and crystalline alloys, TE-TL, of early (TE = Ti, Zr, Nb, Hf) and late (TL = Co, Ni, Cu) transition metals. Here, we briefly overview the main results for the transition from HEAs to CAs in these alloy systems and then present new results for the electronic structure (ES), studied with photoemission spectroscopy and specific heat, atomic structure, thermal, magnetic and mechanical properties of a-TE-TL and Cantor-type alloys. A change in the properties of the alloys studied on crossing from the HEA to the CA concentration range mirrors that in the ES. The compositions of the alloys having the best properties depend on the alloy system and the property selected. This emphasizes the importance of knowing the ES for the design of new compositional complex alloys with the desired properties.


2021 ◽  
Vol 57 (5) ◽  
pp. 1-12
Author(s):  
S.A. Baranov ◽  
◽  
A.I. Dikusar ◽  

It is shown that the earlier discovered features of the composition and properties of electrochemical coatings obtained by the induced codeposition from alloys of iron group metals (W, Mo, Re) such as nanocrystallinity (X-ray amorphism), macroscopic dimensional effects of microhardness and corrosion resistance, the effect of the volume current density on the properties and composition are a consequence of the fractality of the solutions of complexes (citrate, gluconate, etc.) in combination with the intensive interfacial exchange. In this case, the kinetics of nano-nucleation limits the size of the resulting alloy nucleus, as a result of which water molecules participate in the formation of coatings, leading to the incorporation of oxide-hydroxide inclusions into the solid phase and hydrogenation.


2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
A Alshantti

Abstract Introduction Perioperative anemia commonly occurs in patients undoing major surgery. We aimed to assess the efficacy and safety of intravenous iron therapy (IVIT) given compared to standard practice of oral iron in the perioperative period. Design The search strategy was conducted in Medline, Embase, and Cochrane for only eligible clinical trials (randomized controlled trials) comparing IV over oral iron therapy up to July 2019. The primary outcome was the effect of IVIT on the change of hemoglobin level. The secondary outcomes were the effects of IVIT compared to oral iron on ferritin level, mean corpuscular volume, and adverse side effects. Data were collected from each trial and where applicable meta-analyzed using RevMan. Results Six randomized clinical trials that fit our inclusion criteria were included in the study.We found that IVIT increases the level of hemoglobin compared to oral iron (MD: Mean difference 0.90, 95% confidence interval [CI]: 0.44–1.36, P = 0.000). Serum ferritin levels increased significantly in favor of the IV iron group compared to the oral iron group at posttreatment (MD: 106.95, 95% CI: 73.29, 140.62 ng/mL). In addition, marked increases in the pooled mean corpuscular volume (MCV) level were observed in favor of the IVIT (MD: 6.07, 95% CI: −0.88–13.02). There was no significant difference in the rate of adverse effects in both the groups. Conclusions IV iron therapy is more effective than oral iron on increasing hemoglobin, ferritin, and MCV in the perioperative period and is also as safe with no diffidence in the risk of developing adverse side effects.


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