The ephemeris, orbital decay, and masses of 10 eclipsing HMXBs

We take advantage of more than 10 years of monitoring of the eclipsing HMXB systems LMC X-4, Cen X-3, 4U 1700-377, 4U 1538-522, SMC X-1, IGR J18027-2016, Vela X-1, IGR J17252-3616, XTE J1855-026, and OAO 1657-415 with the ASM on-board RXTE and ISGRI on-board INTEGRAL to update their ephemeris. These results are used to refine previous measurements of the orbital period decay of all sources (where available) and provide the first accurate values of the apsidal advance in Vela X-1 and 4U 1538-522. Updated values for the masses of the neutron stars hosted in the ten HMXBs are also provided, as well as the long-term lightcurves folded on the sources best determined orbital parameters. These lightcurves reveal complex eclipse ingresses and egresses, that are understood mostly as being due to the presence of accretion wakes. The results reported in this paper constitute a database to be used for population and evolutionary studies of HMXBs, as well as theoretical modelling of long-term accretion in wind-fed X-ray binaries.Comment: Accepted for publication on A&

Creation and study of formulations as inhibitors of metal corrosion and scaling for stabilization water treatment in water utilization systems (a review)

This review summarizes studies for the past 5 years aimed at creation of efficient organophosphonate reagents for the stabilization water treatment aimed at preventing metal corrosion and scaling in water utilization systems.This study was carried out with state financial support provided by the Russian Ministry of Education and Science under Subsidy Grant Agreement No. 14.576.21.0017 of August 23, 2014

Inclination shallowing in the Permian/Triassic boundary sedimentary sections of the Middle Volga region in light of the new paleomagnetic data

© 2017, Pleiades Publishing, Ltd. One of the key challenges which are traditionally encountered in studying the paleomagnetism of terrigenous sedimentary strata is the necessity to allow for the effect of shallowing of paleomagnetic inclinations which takes place under the compaction of the sediment at the early stages of diagenesis and most clearly manifests itself in the case of midlatitude sedimentation. Traditionally, estimating the coefficient of inclination flattening (f) implies routine re-deposition experiments and studying their magnetic anisotropy (Kodama, 2012), which is not possible in every standard paleomagnetic laboratory. The Elongation–Inclination (E–I) statistical method for estimating the coefficient of inclination shallowing, which was recently suggested in (Tauxe and Kent, 2004), does not require the investigation of the rock material in a specially equipped laboratory but toughens the requirements on the paleomagnetic data and, primarily, regarding the volume of the data, which significantly restricts the possibilities of the post factum estimation and correction for inclination shallowing. In this work, we present the results of the paleomagnetic reinvestigation of the Puchezh and Zhukov ravine (ravine) reference sections of the Upper Permian and Lower Triassic rocks in the Middle Volga region. The obtained paleomagnetic data allowed us to estimate the coefficient of inclination shallowing f by the E–I method: for both sections, it is f = 0.9. This method was also used by us for the paleomagnetic data that were previously obtained for the Permian–Triassic rocks of the Monastyrskii ravine (Monastirskoje) section (Gialanella et al., 1997), where the inclination shallowing coefficient was estimated at f = 0.6

Effect of Fe3O4 Nanoparticles Modified by Citric and Oleic Acids on the Physicochemical and Magnetic Properties of Hybrid Electrospun P(VDF-TrFE) Scaffolds

This study considers a fabrication of magnetoactive scaffolds based on a copolymer of vinylidene fluoride and trifluoroethylene (P(VDF-TrFE)) and 5, 10, and 15 wt.% of magnetite (Fe3O4) nanoparticles modified with citric (CA) and oleic (OA) acids by solution electrospinning. The synthesized Fe3O4-CA and Fe3O4-OA nanoparticles are similar in particle size and phase composition, but differ in zeta potential values and magnetic properties. Pure P(VDF-TrFE) scaffolds as well as composites with Fe3O4-CA and Fe3O4-OA nanoparticles demonstrate beads-free 1 μm fibers. According to scanning electron (SEM) and transmission electron (TEM) microscopy, fabricated P(VDF-TrFE) scaffolds filled with CA-modified Fe3O4 nanoparticles have a more homogeneous distribution of magnetic filler due to both the high stabilization ability of CA molecules and the affinity of Fe3O4-CA nanoparticles to the solvent used and P(VDF-TrFE) functional groups. The phase composition of pure and composite scaffolds includes a predominant piezoelectric β-phase, and a γ-phase, to a lesser extent. When adding Fe3O4-CA and Fe3O4-OA nanoparticles, there was no significant decrease in the degree of crystallinity of the P(VDF-TrFE), which, on the contrary, increased up to 76% in the case of composite scaffolds loaded with 15 wt.% of the magnetic fillers. Magnetic properties, mainly saturation magnetization (Ms), are in a good agreement with the content of Fe3O4 nanoparticles and show, among the known magnetoactive PVDF or P(VDF-TrFE) scaffolds, the highest Ms value, equal to 10.0 emu/g in the case of P(VDF-TrFE) composite with 15 wt.% of Fe3O4-CA nanoparticles. © 2023 by the authors.Russian Science Foundation, RSF: 22-73-00228This research was funded by the Russian Science Foundation, grant number 22-73-00228, https://rscf.ru/project/22-73-00228/

Monolithic and hybrid integration of InAs/GaAs quantum dot microdisk lasers on silicon

A method of hybrid integration of quantum dot microdisk lasers with silicon wafer is proposed and realized. In addition to the possibility of combining microlasers with various silicon-based electronic and photonic devices, this makes it possible to significantly improve heat removal from the active region of the microlaser. The thermal resistance normalized to the mesa area reaches the level of about 0.002 (K/W)*cm2, which is significantly lower than the corresponding values of QD microlasers on GaAs substrate and monolithically grown on Si. As a result, the threshold current as well as current-induced shift of emission wavelength are reduced in continuous-wave regime

Применение идаруцизумаба при выполнении экстренных хирургических вмешательств пациентам, принимавшим дабигатран

This article presents modern possibilities for the provision of emergency surgical care to patients with atrial fibrillation, who administered dabigatran etexilate. We describe two clinical situations, in which idarucizumab, a specific dabigatran antagonist, which is a monoclonal antibody fragment that binds dabigatran, was used to neutralize the anticoagulant effect of dabigatran etexilate before emergency surgery. In the first case, the patient developed acute gangrenous calculous cholecystitis, in the second a patient required an urgent epicystostomy. In both cases, the successful outcome of surgical interventions was due to the effective interactions of the team of specialists and adherence to the algorithm for providing emergency care to such patients, as well as the presence of idarucizumab in hospitals. The postoperative management of patients and the timely resumption of anticoagulant therapy to prevent thromboembolic complications is no less important. The presented clinical cases confirm the feasibility of using idarucizumab to provide emergency surgical care to patients on dabigatran etexilate, as well as the need to take into account the possible risk of emergency interventions when anticoagulant therapy is prescribed to patients with atrial fibrillation. This paper discusses special risk groups of patients in whom rapid reversal of anticoagulation is required due to altered hemostasis.We outline data of a prospective cohort study (RE-VERSE AD), which examined the efficacy and safety of idarucizumab in patients with uncontrolled bleeding and in patients requiring urgent surgery. We also present the RE-VECTO study data on the use of idarucizumab in real-life clinical practice.В статье представлены современные возможности оказания экстренной хирургической помощи пациентам с фибрилляцией предсердий, принимавшим дабигатрана этексилат. Описаны две клинические ситуации, в которых перед экстренным хирургическим вмешательством для нейтрализации антикоагулянтного эффекта дабигатрана этексилата был применен его специфический антагонист – идаруцизумаб, представляющий собой фрагмент моноклонального антитела с высокой связывающей активностью в отношении дабигатрана. В первом случае у пациента развился острый гангренозный калькулезный холецистит, во втором больному потребовалось экстренное наложение эпицистостомы. В обоих случаях успешный исход оперативных вмешательств был обусловлен эффективным взаимодействием команды специалистов с соблюдением алгоритма оказания неотложной помощи таким пациентам, а также наличием в стационарах идаруцизумаба. Не менее важными являются послеоперационное ведение пациентов и своевременное возобновление антикоагулянтной терапии для профилактики тромбоэмболических осложнений. Представленные клинические случаи подтверждают целесообразность применения идаруцизумаба при оказании экстренной хирургической помощи пациентам, принимавшим дабигатрана этексилат, а также необходимость учитывать возможный риск неотложных вмешательств при назначении антикоагулянтной терапии у пациентов с фибрилляцией предсердий. В представленной работе обсуждаются группы пациентов особого риска, которым может потребоваться экстренная реверсия антикоагулянтной активности на фоне измененного гемостаза. Представлены данные проспективного когортного исследования RE-VERSE AD, в котором были изучены эффективность и безопасность идаруцизумаба у пациентов с неконтролируемыми кровотечениями и у пациентов, которым требовалось ургентное оперативное вмешательство. Также представлены данные исследования RE-VECTO об использовании идаруцизумаба в реальной клинической практике

The chlorosome: a prototype for efficient light harvesting in photosynthesis

Three phyla of bacteria include phototrophs that contain unique antenna systems, chlorosomes, as the principal light-harvesting apparatus. Chlorosomes are the largest known supramolecular antenna systems and contain hundreds of thousands of BChl c/d/e molecules enclosed by a single membrane leaflet and a baseplate. The BChl pigments are organized via self-assembly and do not require proteins to provide a scaffold for efficient light harvesting. Their excitation energy flows via a small protein, CsmA embedded in the baseplate to the photosynthetic reaction centres. Chlorosomes allow for photosynthesis at very low light intensities by ultra-rapid transfer of excitations to reaction centres and enable organisms with chlorosomes to live at extraordinarily low light intensities under which no other phototrophic organisms can grow. This article reviews several aspects of chlorosomes: the supramolecular and molecular organizations and the light-harvesting and spectroscopic properties. In addition, it provides some novel information about the organization of the baseplate

Inclination shallowing in the Permian/Triassic boundary sedimentary sections of the Middle Volga region in light of the new paleomagnetic data

© 2017, Pleiades Publishing, Ltd. One of the key challenges which are traditionally encountered in studying the paleomagnetism of terrigenous sedimentary strata is the necessity to allow for the effect of shallowing of paleomagnetic inclinations which takes place under the compaction of the sediment at the early stages of diagenesis and most clearly manifests itself in the case of midlatitude sedimentation. Traditionally, estimating the coefficient of inclination flattening (f) implies routine re-deposition experiments and studying their magnetic anisotropy (Kodama, 2012), which is not possible in every standard paleomagnetic laboratory. The Elongation–Inclination (E–I) statistical method for estimating the coefficient of inclination shallowing, which was recently suggested in (Tauxe and Kent, 2004), does not require the investigation of the rock material in a specially equipped laboratory but toughens the requirements on the paleomagnetic data and, primarily, regarding the volume of the data, which significantly restricts the possibilities of the post factum estimation and correction for inclination shallowing. In this work, we present the results of the paleomagnetic reinvestigation of the Puchezh and Zhukov ravine (ravine) reference sections of the Upper Permian and Lower Triassic rocks in the Middle Volga region. The obtained paleomagnetic data allowed us to estimate the coefficient of inclination shallowing f by the E–I method: for both sections, it is f = 0.9. This method was also used by us for the paleomagnetic data that were previously obtained for the Permian–Triassic rocks of the Monastyrskii ravine (Monastirskoje) section (Gialanella et al., 1997), where the inclination shallowing coefficient was estimated at f = 0.6

Inclination shallowing in the Permian/Triassic boundary sedimentary sections of the Middle Volga region in light of the new paleomagnetic data

© 2017, Pleiades Publishing, Ltd. One of the key challenges which are traditionally encountered in studying the paleomagnetism of terrigenous sedimentary strata is the necessity to allow for the effect of shallowing of paleomagnetic inclinations which takes place under the compaction of the sediment at the early stages of diagenesis and most clearly manifests itself in the case of midlatitude sedimentation. Traditionally, estimating the coefficient of inclination flattening (f) implies routine re-deposition experiments and studying their magnetic anisotropy (Kodama, 2012), which is not possible in every standard paleomagnetic laboratory. The Elongation–Inclination (E–I) statistical method for estimating the coefficient of inclination shallowing, which was recently suggested in (Tauxe and Kent, 2004), does not require the investigation of the rock material in a specially equipped laboratory but toughens the requirements on the paleomagnetic data and, primarily, regarding the volume of the data, which significantly restricts the possibilities of the post factum estimation and correction for inclination shallowing. In this work, we present the results of the paleomagnetic reinvestigation of the Puchezh and Zhukov ravine (ravine) reference sections of the Upper Permian and Lower Triassic rocks in the Middle Volga region. The obtained paleomagnetic data allowed us to estimate the coefficient of inclination shallowing f by the E–I method: for both sections, it is f = 0.9. This method was also used by us for the paleomagnetic data that were previously obtained for the Permian–Triassic rocks of the Monastyrskii ravine (Monastirskoje) section (Gialanella et al., 1997), where the inclination shallowing coefficient was estimated at f = 0.6