NGC 7468: a galaxy with an inner polar disk

We present our spectroscopic observations of the galaxy NGC 7468 performed at the 6-m Special Astrophysical Observatory telescope using the UAGS long-slit spectrograph, the multipupil fiber spectrograph MPFS, and the scanning Fabry-Perot interferometer (IFP). We found no significant deviations from the circular rotation of the galactic disk in the velocity field in the regions of brightness excess along the major axis of the galaxy (the putative polar ring). Thus, these features are either tidal structures or weakly developed spiral arms. However, we detected a gaseous disk at the center of the galaxy whose rotation plane is almost perpendicular to the plane of the galactic disk. The central collision of NGC 7468 with a gas-rich dwarf galaxy and their subsequent merging seem to be responsible for the formation of this disk.Comment: 8 pages, 6 figures, accepted in Astronomy Letters, 2004, vol 30., N 9, p. 58

The Nature of UCDs: Internal Dynamics from an Expanded Sample and Homogeneous Database

We have obtained high-resolution spectra of 23 ultra-compact dwarf galaxies (UCDs) in the Fornax cluster with -10.4>M_V>-13.5 mag (10^6<M/M_*<10^8), using FLAMES/Giraffe at the VLT. This is the largest homogeneous data set of UCD internal dynamics assembled to date. We derive dynamical M/L ratios for 15 UCDs covered by HST imaging. In the M_V-sigma plane, UCDs with M_V<-12 mag are consistent with the extrapolated Faber-Jackson relation for luminous ellipticals, while fainter UCDs are closer to the extrapolated globular cluster (GC) relation. At a given metallicity, Fornax UCDs have on average 30-40% lower M/L ratios than Virgo UCDs, suggesting possible differences in age or dark matter content between Fornax and Virgo UCDs. For our sample of Fornax UCDs we find no significant correlation between M/L ratio and mass. We combine our data with available M/L ratio measurements of compact stellar systems with 10^4<M/M_*<10^8, and normalise all M/L estimates to solar metallicity. We find that UCDs (M > 2*10^6 M_*) have M/L ratios twice as large as GCs (M < 2*10^6 M_*). We show that stellar population models tend to under-predict dynamical M/L ratios of UCDs and over-predict those of GCs. Considering the scaling relations of stellar spheroids, UCDs align well along the 'Fundamental Manifold', constituting the small-scale end of the galaxy sequence. The alignment for UCDs is especially clear for r_e >~ 7 pc, which corresponds to dynamical relaxation times that exceed a Hubble time. In contrast, GCs exhibit a broader scatter and do not appear to align along the manifold. We argue that UCDs are the smallest dynamically un-relaxed stellar systems, with M > 2*10^6 M_* and 7<r_e<100 pc. Future studies should aim at explaining the elevated M/L ratios of UCDs and the environmental dependence of their properties.Comment: 17 pages, 14 figures, accepted for publication in A&A. V3 taking into account proof corrections: Table 3 radial velocity entries corrected by heliocentric correction, updated sigma entries in Table 5 for a few CenA sources, updated references for G1 and omega Ce

Inner Polar Rings and Disks: Observed Properties

A list of galaxies with inner regions revealing polar (or strongly inclined to the main galactic plane) disks and rings is compiled from the literature data. The list contains 47 galaxies of all morphological types, from E to Irr. We consider the statistics of the parameters of polar structures known from observations. The radii of the majority of them do not exceed 1.5 kpc. The polar structures are equally common in barred and unbarred galaxies. At the same time, if a galaxy has a bar (or a triaxial bulge), this leads to the polar disk stabilization - its axis of rotation usually coincides with the major axis of the bar. More than two thirds of all considered galaxies reveal one or another sign of recent interaction or merging. This fact indicates a direct relation between the external environment and the presence of an inner polar structure.Comment: 12 pages, 3 figures, accepted to Astrophysical Bulletin. Minor changes and corrections are still possibl

Влияние отжига на недиагональный магнитоимпеданс в аморфных проводах

Magnetoimpedance (MI) effect in amorphous ferromagnetic microwires represents is the ideal base for sensing technology and is currently used to develop high sensitive sensors of weak  magnetic fields with a resolution up to few micro−Oersteds. The effect  of heat treatment on off−diagonal MI in glass coated ferromagnetic amorphous microwires has been studied in order to improve MI sensitivity and temperature stability. We have shown the dependence of sensor signal on temperature. The wires had Co−based composition and internal stress induced helical or circumferential anisotropy. We have demonstrated that annealing of the entire sensing element including the electric contacts and the detection coil may improve the sensitivity of the output signal  to an external magnetic field by about 25% and  decrease its temperature sensitivity almost twofold in the −30…+80 °C range. These improvements require strict control  of the annealing parameters. The best results are obtained for annealing at 160 °C for 2−3 minutes. The experimentally observed changes  are  related with stress relaxation during  annealing; in particular; relaxation of the  stresses occurring during  solidification  due  to the  difference in the  thermal expansion coefficients of the metal core  and the glass sheet.Магнитоимпедансный эффект в ферромагнитных аморфных микропроводах является идеальной основой для разработки высокочувствительных сенсоров слабых магнитных полей  с разрешением до нескольких микроэрстед. Приведены результаты исследования температурной зависимости сигнала датчиков с магниточувствительным элементом на основе аморфных кобальт−содержащих микропроводов с геликоидальной магнитной анизотропией. Также рассмотрено и влияние температурной обработки на недиагональный магнитоимпеданс (МИ) в них. Установлено; что определенные режимы отжига МИ−датчиков; включающих микро-провод с электрическими контактами и детектирующую катушку; увеличивают чувствительность выходного сигнала к осевому внешнему магнитному полю и уменьшают его зависимость от температуры.  В процессе изучения данного явления была разработана методика термической обработки датчиков на основе аморфных микропроводов и проведено исследование влияния режимов отжига на чувствительность и температурную стабильность недиагонального магнитоимпеданса в микропроводах. После проведения термообработки при температуре отжига 160 °С в течение 2—3 мин наблюдали увеличение чувствительности датчиков к осевому внешнему полю на 25 % и снижение зависимости сигнала от температуры почти в 2 раза. Эти изменения связаны с релаксацией внутренних напряжений; которые определяют эффективную магнитную анизотропию аморфного МИ−провода

Image-Subtraction Photometry of the Globular Cluster M3: identification of new double-mode RR Lyrae stars

We have applied the image subtraction method to the M3 dataset previously analyzed by Corwin & Carney (2001; CC01). The new analysis produced light curves and periods for 15 variables, bringing to 222 the total number of RR Lyrae stars in CC01 M3 dataset. We have identified three new candidate double-mode (RRd) variables (V13, V200, and V251) in M3. Of the newly discovered RRd's V13 is unusual in that it has the fundamental as the dominant pulsation mode. Two of the new candidate RRd's (V13 and V200) have period ratios as low as 0.738-0.739. They lie separated from all previously known RRd's in the Petersen diagram, in positions implying a large spread in mass and/or, less likely, in heavy element mass fraction, among the M3 horizontal branch (HB) stars. We explore mass transfer and helium enhancement as possible explanations for the apparent spread in HB masses. We also note that the masses derived from the RRd analyses now favor little mass loss on the red giant branch. V200 has changed its dominant pulsation mode from fundamental to first overtone, while V251 has changed its dominant mode from first overtone to fundamental in the interval 1992 to 1993. Together with M3-V166 this is the first time that RRd variables are observed to switch their dominant pulsation modes while remaining RRd's. The phenomenon is found to occur in a one year time-span thus suggesting that these stars are undergoing a rapid evolutionary phase, and that both redward and blueward evolution may take place among the HB stars in M3. The unusual behavior of the M3 RRd's is discussed and compared to that of the RRd's identified so far in globular clusters and in the field of our and other Local Group galaxies. We find lack of correlation between the presence of RRd variables and any of the cluster structural parameters.Comment: 38 pages, 16 figures, AJ in pres

A review of elliptical and disc galaxy structure, and modern scaling laws

A century ago, in 1911 and 1913, Plummer and then Reynolds introduced their models to describe the radial distribution of stars in `nebulae'. This article reviews the progress since then, providing both an historical perspective and a contemporary review of the stellar structure of bulges, discs and elliptical galaxies. The quantification of galaxy nuclei, such as central mass deficits and excess nuclear light, plus the structure of dark matter halos and cD galaxy envelopes, are discussed. Issues pertaining to spiral galaxies including dust, bulge-to-disc ratios, bulgeless galaxies, bars and the identification of pseudobulges are also reviewed. An array of modern scaling relations involving sizes, luminosities, surface brightnesses and stellar concentrations are presented, many of which are shown to be curved. These 'redshift zero' relations not only quantify the behavior and nature of galaxies in the Universe today, but are the modern benchmark for evolutionary studies of galaxies, whether based on observations, N-body-simulations or semi-analytical modelling. For example, it is shown that some of the recently discovered compact elliptical galaxies at 1.5 < z < 2.5 may be the bulges of modern disc galaxies.Comment: Condensed version (due to Contract) of an invited review article to appear in "Planets, Stars and Stellar Systems"(www.springer.com/astronomy/book/978-90-481-8818-5). 500+ references incl. many somewhat forgotten, pioneer papers. Original submission to Springer: 07-June-201

The stellar and sub-stellar IMF of simple and composite populations

The current knowledge on the stellar IMF is documented. It appears to become top-heavy when the star-formation rate density surpasses about 0.1Msun/(yr pc^3) on a pc scale and it may become increasingly bottom-heavy with increasing metallicity and in increasingly massive early-type galaxies. It declines quite steeply below about 0.07Msun with brown dwarfs (BDs) and very low mass stars having their own IMF. The most massive star of mass mmax formed in an embedded cluster with stellar mass Mecl correlates strongly with Mecl being a result of gravitation-driven but resource-limited growth and fragmentation induced starvation. There is no convincing evidence whatsoever that massive stars do form in isolation. Various methods of discretising a stellar population are introduced: optimal sampling leads to a mass distribution that perfectly represents the exact form of the desired IMF and the mmax-to-Mecl relation, while random sampling results in statistical variations of the shape of the IMF. The observed mmax-to-Mecl correlation and the small spread of IMF power-law indices together suggest that optimally sampling the IMF may be the more realistic description of star formation than random sampling from a universal IMF with a constant upper mass limit. Composite populations on galaxy scales, which are formed from many pc scale star formation events, need to be described by the integrated galactic IMF. This IGIMF varies systematically from top-light to top-heavy in dependence of galaxy type and star formation rate, with dramatic implications for theories of galaxy formation and evolution.Comment: 167 pages, 37 figures, 3 tables, published in Stellar Systems and Galactic Structure, Vol.5, Springer. This revised version is consistent with the published version and includes additional references and minor additions to the text as well as a recomputed Table 1. ISBN 978-90-481-8817-

Plant Diversity Changes during the Postglacial in East Asia: Insights from Forest Refugia on Halla Volcano, Jeju Island

Understanding how past climate changes affected biodiversity is a key issue in contemporary ecology and conservation biology. These diversity changes are, however, difficult to reconstruct from paleoecological sources alone, because macrofossil and pollen records do not provide complete information about species assemblages. Ecologists therefore use information from modern analogues of past communities in order to get a better understanding of past diversity changes. Here we compare plant diversity, species traits and environment between late-glacial Abies, early-Holocene Quercus, and mid-Holocene warm-temperate Carpinus forest refugia on Jeju Island, Korea in order to provide insights into postglacial changes associated with their replacement. Based on detailed study of relict communities, we propose that the late-glacial open-canopy conifer forests in southern part of Korean Peninsula were rich in vascular plants, in particular of heliophilous herbs, whose dramatic decline was caused by the early Holocene invasion of dwarf bamboo into the understory of Quercus forests, followed by mid-Holocene expansion of strongly shading trees such as maple and hornbeam. This diversity loss was partly compensated in the Carpinus forests by an increase in shade-tolerant evergreen trees, shrubs and lianas. However, the pool of these species is much smaller than that of light-demanding herbs, and hence the total species richness is lower, both locally and in the whole area of the Carpinus and Quercus forests. The strongly shading tree species dominating in the hornbeam forests have higher leaf tissue N and P concentrations and smaller leaf dry matter content, which enhances litter decomposition and nutrient cycling and in turn favored the selection of highly competitive species in the shrub layer. This further reduced available light and caused almost complete disappearance of understory herbs, including dwarf bamboo

Eribulin-trastuzumab combination in HER2-positive metastatic breast cancer: updated results from a Russian observational study

Introduction. The standard of 1st line treatment of HER2+ metastatic breast cancer (mBC) is double blockade with trastuzumab and pertuzumab + taxane, 2nd line – Trastuzumab-emtazine. There are no standards for further treatment, as well as the optimal drug sequence. Expansion of the arsenal of therapeutic possibilities and the use of new combinations will certainly improve the results of treatment of this category of patients and increase their life expectancy.Aim. We sought to describe treatment patterns of  eribulin  and clinical outcomes of  metastatic HER2-positive breast cancer treated with eribulin  plus trastuzumab combination in  academic institutions and community oncology practices across the Russian Federation.Materials and methods. Patients treated with eribulin anytime between Jan, 2014 and Sep, 2019 with a diagnosis of MBC were identified by 23 providers from Russia. Providers retrospectively reviewed the health records and abstracted selected data points into an electronic case report form for each eligible patient.Results. 100 HER2-positive pts received eribulin in combination with trastuzumab. Median age was 55 (31–80) yrs and ECOG status 0–3. 67% pts had visceral metastases. Eribulin was administered as 1st and 2nd line to 23 (23%) pts, 3rd line to 31 (31%) pts, 4th line and later to 46 (46%). Median number of cycles was 5 (2–27). ORR was 12%, SD – 72%, SD &gt; 6 months – 23%, PD – 16%. Clinical efficacy rate achieved in 35%. Median PFS was 5.07 months (95% CI 4.021–6.119). According to the ER-status the response to eribulin and trastuzumab was different. ORR was 18.8%, SD 72.9% in pts with ER-positive MBC (n = 48) and 5.8% and 71.2% respectively in ER-negative MBC (n = 52). Median PFS was 6.97 months (95% CI 3.924–10.016) in pts with ER-positive MBC and 4.67 months (95% CI 3.841–5.499) in ER-negative MBC (р = 0.3). The combination was well tolerated: dose reductions were required in 12% pts, withdrawal due to toxicity in 4% pts. The most common type of toxicity was hematological with neutropenia Gr III-IV in 14 (14%) pts. Peripheral neuropathy Gr III was observed in 5 (5%) pts. No cardiotoxicity was detected.Conclusions. This is the real-life data of clinical outcomes for patients receiving eribulin plus trastuzumab for HER2-positive MBC throughout the Russian Federation. Our experience with eribulin plus trastuzumab demonstrates that this combination may be a potential effective treatment option for HER-2 positive MBC patients

May Measurement Month 2018: a pragmatic global screening campaign to raise awareness of blood pressure by the International Society of Hypertension

Aims Raised blood pressure (BP) is the biggest contributor to mortality and disease burden worldwide and fewer than half of those with hypertension are aware of it. May Measurement Month (MMM) is a global campaign set up in 2017, to raise awareness of high BP and as a pragmatic solution to a lack of formal screening worldwide. The 2018 campaign was expanded, aiming to include more participants and countries. Methods and results Eighty-nine countries participated in MMM 2018. Volunteers (≥18 years) were recruited through opportunistic sampling at a variety of screening sites. Each participant had three BP measurements and completed a questionnaire on demographic, lifestyle, and environmental factors. Hypertension was defined as a systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg, or taking antihypertensive medication. In total, 74.9% of screenees provided three BP readings. Multiple imputation using chained equations was used to impute missing readings. 1 504 963 individuals (mean age 45.3 years; 52.4% female) were screened. After multiple imputation, 502 079 (33.4%) individuals had hypertension, of whom 59.5% were aware of their diagnosis and 55.3% were taking antihypertensive medication. Of those on medication, 60.0% were controlled and of all hypertensives, 33.2% were controlled. We detected 224 285 individuals with untreated hypertension and 111 214 individuals with inadequately treated (systolic BP ≥ 140 mmHg or diastolic BP ≥ 90 mmHg) hypertension. Conclusion May Measurement Month expanded significantly compared with 2017, including more participants in more countries. The campaign identified over 335 000 adults with untreated or inadequately treated hypertension. In the absence of systematic screening programmes, MMM was effective at raising awareness at least among these individuals at risk