Abstract
There are about a dozen symbiotic stars known to produce high-velocity jets during outbursts. MWC 560 (V694 Mon) is a symbiotic star that seems to show a permanent jet. After showing an ...unexpected brightening in 2018 November, it has continued to brighten until 2021 and is currently in the brightest state ever. We have been conducting long-term high-dispersion spectroscopic monitoring of this object since 2016 March. An emission wing with vFWHM ≈ 700 km s−1 in the hydrogen Balmer line at an unexpected brightening event in 2018 was reported by Ando et al. (2021, PASJ, 73, L1). In subsequent continuous observations, this emission wing was no longer seen on 2019 February 6. The absorption lines seen in the hydrogen Balmer lines are gradually deepening and spreading to the slower side of the velocity, and the outflow velocity is becoming slower. The expanding component generated by the outburst was initially observed in the emission wing just after the 2018 outburst, got gradually cooler, and was observed in the absorption line after 2019.
Abstract
MWC 560 (V694 Mon) is classified as a symbiotic binary consisting of a white dwarf and an M5III red giant. In this object, a very- high-speed component, thought to be a jet, has been ...reported in the hydrogen Balmer line. We have been conducting long-term spectroscopic monitoring since the brightening in 2016 February. An irregular rebrightening was reported by Goranskij et al. (2018, Astronomer’s Telegram, 12227), who also showed that the high-velocity absorption component was not seen on 2018 November 16. Our low-resolution spectroscopic observations showed no high-velocity absorption component on 2018 November 14, and wide emission lines in Balmer line region (Hα, Hβ). However, high-resolution spectroscopy revealed the presence of slow, weak absorbing components and an emission wing on 2018 December 25. MWC 560 began to brighten in 2018 November, and it is gradually brightening as of 2020 April 14. For the absorption component, we propose a shell expansion of a classical symbiotic nova that occurred in 2016. During the 2018 brightening a new emission wing with vFWHM ≈ 700 km s−1 was confirmed, which could be triggered by disk instability like a dwarf nova. This paper summarizes the results of long-term monitoring observations and the recent changes in MWC 560.
1. Conditions for preparation of apolaccase EC 1.10. 3. 2 and reconstruction of the holo-enzyme by treatment with copper ion were examined. The apo enzyme was prepared by dialysis against 10–20 mM ...cyanide solution containing 20–50 mM ascorbate at pH 7.0–7.4. The properties of native laccase, such as its activity, copper content, absorption spectrum and electron spin resonance spectrum, were almost completely regained by treatment of this apo-protein with cuprous ion and the percentage reconstruction was 70 to 90%. Some, though much less reconstruction was achieved by treatment of apo-enzyme with cupric ion. 2. The relationships between the copper content, the absorbancy at 615 mμ and the activity were studied using “partial apo-enzymes,” derivatives of native enzyme containing various amounts of copper obtained during cyanide-treatment. The decrease in activity of the “partial apo-enzymes” was much larger than the decrease in their copper content. Thus, removal of half the initial amount of copper resulted in loss of more than 90% of the original activity. The cooperative action of copper atoms in the laccase reaction is suggested.
A synthetic route to 2-O-(diphenylacetyl)salicylic acid derivatives was developed and the effects of the products on the heat-denaturation of albumin and on heat-induced erythrocytolysis were ...examined (in vitro anti-inflammation test). Trichloroethyl salicylate was acylated with diphenylacetic acid and its derivatives in the presence of methanesulfonyl chloride and pyridine, and the products were deprotected with zinc-acetic acid to give 2-O-(diphenylacetyl)salicylic acid derivatives. Their biological effects resembled those of ibuprofen.
Effect of endotoxin from E. coli on the ATP content in heart muscle, the liver and the kidney of thyrotoxic rats was studied. When endotoxin (200-400 μg) was intravenously injected to rats taking ...drinking water containing 2-7.5 μg T3 per ml, body temperature rose and the heart rate increased. At the same time, a marked decrease in the ATP content in heart muscle and the kidney was observed together with an increase in Na+-K+-ATPase activity. Such changes were not observed or seen only to a small extent in euthyroid rats after endotoxin administration. Endotoxin-induced ATP depletion in T3-treated rats was prevented by administration of 5 mg hydrocortisone just prior to endotoxin injection. These findings indicate that endotoxin easily causes ATP depletion in some tissue or organs in thyrotoxicosis, even if the dose of endotoxin is not enough to produce such an effect in the euthyroid. These observations are of interest in relation to thyroid storm associated with bacterial infection.
Continuing the project described by Kato et al. (2009, arXiv:0905.1757), we collected times of superhump maxima for 128 SU UMa-type dwarf novae observed mainly during the 2015-2016 season and ...characterized these objects. The data have improved the distribution of orbital periods, the relation between the orbital period and the variation of superhumps, the relation between period variations and the rebrightening type in WZ Sge-type objects. Coupled with new measurements of mass ratios using growing stages of superhumps, we now have a clearer and statistically greatly improved evolutionary path near the terminal stage of evolution of cataclysmic variables. Three objects (V452 Cas, KK Tel, ASASSN-15cl) appear to have slowly growing superhumps, which is proposed to reflect the slow growth of the 3:1 resonance near the stability border. ASASSN-15sl, ASASSN-15ux, SDSS J074859.55+312512.6 and CRTS J200331.3-284941 are newly identified eclipsing SU UMa-type (or WZ Sge-type) dwarf novae. ASASSN-15cy has a short (~0.050 d) superhump period and appears to belong to EI Psc-type objects with compact secondaries having an evolved core. ASASSN-15gn, ASASSN-15hn, ASASSN-15kh and ASASSN-16bu are candidate period bouncers with superhump periods longer than 0.06 d. We have newly obtained superhump periods for 79 objects and 13 orbital periods, including periods from early superhumps. In order that the future observations will be more astrophysically beneficial and rewarding to observers, we propose guidelines how to organize observations of various superoutbursts.
Galactorrhea was found in 5 patients with subclinical hypothyroidism. The galactorrhea consisted of the discharge of a few drops of milk only under pressure. Serum T4 was in the lower level of the ...normal range, but serum T3 was normal (T4: 6.3±1.2μg/dl, T3: 113±7ng/dl). Basal serum TSH and PRL were slightly increased only in 2 and 1 cases, respectively. The PRL responses to TRH stimulation were exaggerated in all cases, although the basal levels were normal. An enlarged pituitary gland was observed in 1 patient by means of CT scanning. All patients were treated by T4 replacement. In serial TRH tests during the T4 replacement therapy, the PRL response was still increased even when the TSH response was normalized. Galactorrhea disappeared when the patients were treated with an increased dose of T4 (150-200μg/day). Recurrence of galactorrhea was not observed even though replacement dose of T4 was later decreased to 100μg/day in 4 cases. In patients with galactorrhea of unknown origin, subclinical hypothyroidism should not be ruled out even when their serum T4, T3, TSH and PRL are in the normal range. The TRH stimulation test is necessary to detect an exaggerated PRL response, as the cause of the galactorrhea. To differentiate this from pituitary microadenoma, observation of the effects of T4 replacement therapy on galactorrhea is essential.
alpha-Difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, reduced intestinal lesions in tumor-bearing mice caused by treatment with N3-(3-methylbenzoyl)-3',5'-diacetyl ...corrected-FUDR (FF-705), a derivative of 5-fluoro-2'-deoxyuridine (FUDR). FF-705 at 32 mg/kg (the effective dose) suppressed tumor growth to about 40% of the control level. At this dose, body weight gain was suppressed slightly when FF-705 was given alone, and this change was milder in the DFMO-supplemented group. Intestinal lesions were suppressed almost completely by concomitant treatment with DFMO. The gross lesion index in the combined treatment group was similar to that in the controls and significantly smaller than in the FF-705-alone group (0.3 and 1.9, respectively). The histological lesion index in the combined treatment group was also significantly smaller than in the FF-705-alone group (7.9 and 23.8, respectively). When FF-705 was given at 64 mg/kg, the intestinal mucosal lesions were more severe, but DFMO supplementation reduced them by approximately 50%. Moreover, maltase and diamine oxidase activities of intestinal epithelium remained higher with combined treatment than with FF-705 alone. With FF-705 at 256 mg/kg (a toxic dose), DFMO had little protective effect against intestinal damage.
PDF
