Search

We present a photometric and spectroscopic study of AzV322, an emission line object located in the Small Magellanic Cloud previously classified between O9 and B0. We analyse 17.5 yr of I- and V-band OGLE-II, -III and -IV light curves and find four significant frequencies, viz. f1 = 0.386 549 ± 0.000 003, f2 = 0.101 177 ± 0.000 005, f3 = 0.487 726 ± 0.000 015 and f4 = 0.874 302 ± 0.000 020 cycles d-1. The f1 frequency (period 2.587 00 ± 0.000 02 d) provides the stronger periodogram peak and gives a single wave light curve of full amplitude 0.066 mag in the I band. High-resolution optical spectroscopy confirms the early B-type spectral type and reveals prominent double peak Balmer, Paschen, OI 8446 and He I 5875 emissions. The spectral energy distribution shows significant colour excess towards long wavelengths possibly attributed to free-free emission in a disc -like envelope. Our analysis yields Teff = 23 000 ± 1500 K, log g = 3.0 ± 0.5, M = 16 ± 1 M⊙, R = 31.0 ± 1.1 R⊙ and Lbol = 104.87 ± 0.06 L⊙. AzV322 might be a member of the new class of slowly pulsating B supergiants introduced by Saio et al. and documented by Lefever, Puls & Aerts; however its circumstellar disc makes it an hither to unique object. Furthermore, we notice that an O-C analysis for f1 reveals quasi-cyclic changes for the times of maximum in a time-scale of 20 yr, which might indicate a light-travel time effect in a very wide orbit binary with an undetected stellar component. [ABSTRACT FROM AUTHOR]

We investigate the luminous star ELHC 10 located in the bar of the Large Magellanic Cloud (LMC), concluding that it is a SB1 long-period eclipsing binary where the main eclipse is produced by an opaque structure hiding the secondary star. For the more luminous component we determine an effective temperature of 6500±250 K, log g=1.0±0.5 and luminosity 5970 L⊙. From the radial velocities of their photospheric lines, we calculate a mass function of 7.37 ± 0.55 M⊙. Besides Balmer and forbidden NII emission, we find splitting of metallic lines, characterized by strong discrete absorption components, alternatively seen at the blue and red side of the photospheric spectrum. These observations hardly can be interpreted in terms of an structured atmosphere but might reflect mass streams in an interacting binary. The primary shows signatures of s-process nucleosynthesis and might be a low-mass post-asymptotic giant branch star with a rare evolutionary past if the binary is semidetached. The peak separation and constancy of radial velocity in Hα suggest that most of the Balmer emission comes from a circumbinary disc. [ABSTRACT FROM AUTHOR]

We analyse multicolour light curves and high-resolution optical spectroscopy of the eclipsing binary and double periodic variable (DPV) OGLE 05155332−6925581. According to Mennickent et al., this system shows a significant change in the long non-orbital photometric cycle, a loop in the colour–magnitude diagram during this cycle and discrete spectral absorption components that were interpreted as evidence of systemic mass loss. We find that the best fit to the multiband light curves requires a circumprimary optically thick disc with a radius about twice the radius of the more massive star. The spectroscopy indicates a mass ratio of 0.21 ± 0.02 and masses for the hot and cool stars of 9.1 ± 0.5 and 1.9 ± 0.2 M⊙, respectively. A comparison with synthetic binary-star evolutionary models indicates that the system has an age of 4.76 × 107 yr, and is in the phase of rapid mass transfer, the second one in the life of this binary, in a Case-B mass-exchange stage. Donor-subtracted Hα profiles show the presence of double emission formed probably in an optically thin circumstellar medium, while the variable He i profile and the Hβ absorption wings are probably formed in the optically thick circumprimary disc. The model that best fits the observations shows the system with a relatively large mass transfer rate of $\dot{M}$ = 3.1 × 10−6 M⊙ yr−1. However, the orbital period remains relatively stable during almost 15 yr. This observation suggests that the hotspot mass-loss model proposed by other authors is not adequate in this case, and that some other mechanism is efficiently removing angular momentum from the binary. Furthermore, our observations suggest that the DPV phenomenon could have an important effect in the balance of mass and angular momentum in the system. [ABSTRACT FROM PUBLISHER]

Mondor’s disease (MD) is a rare condition, which is considered a thrombophlebitis of the subcutaneous veins. It commonly occurs on the anterolateral thoracoabdominal wall, but it can also occur on the penis, groin, antecubital fossa and posterior cervical region. The clinical features are a sudden and typically asymptomatic onset of a cord-like induration, although some patients report a feeling of ‘strain’. It is a self-limiting process that lasts a short period of time, which may be the reason why there are few reports about its diagnosis and treatment. Its pathogenesis has remained unclear, because of the lack of methods to reliably differentiate between veins and lymphatic vessels. Immunohistochemical staining for CD31 and D240 has been identified recently as the best method to distinguish small veins from lymphatic vessels, making it a valuable technique in diagnosing not only MD, but also many other diseases in which veins or lymphatic vessels are affected. MD has been associated with several systemic diseases such as breast cancer and hypercoagulability states, thus laboratory studies are recommended to exclude any possible systemic disorders. As this condition is usually a benign and self-limiting process, vigorous treatment is only recommended when the process is symptomatic or recurrent. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 97-year-old woman who was referred with a fast growing lesion on her forehead. The patients' histopathological examination presented a densely cellular neoplastic proliferation while the immunohistochemistry unveiled expression by the neoplastic cells of CD10 and membranous and cytoplasmic CD31, CD68 and CNA42. The patient was diagnosed with pleomorphic dermal sarcoma (PDS), a tumour similar to atypical fibroxanthoma (AFX).

Mondor’s disease of the penis is usually a benign, self-limiting process of acute onset. To date, there have been few studies about its diagnosis and treatment. It is difficult to differentiate MD of the penis from sclerosing lymphangitis of the penis, because the symptoms, epidemiology and aetiology are similar, and because veins are histologically very similar to lymphatics. We report a case of MD in which immunochemical markers such as CD31 and D240 allowed us to specifically discriminate between the small vein and lymphatic vessels. This is important not only for the recognition of MD at any site, but for many other diseases in which veins or lymphatic vessels are affected. [ABSTRACT FROM AUTHOR]