Investigation of relative motion in the triple system ADS 48 on the basis of Gaia DR2 and Pulkovo 26-inch refractor observations

There are high-precision positions, proper motions, parallaxes and radial velocities at the instant 2015.5 for all three components of the star ADS 48 ABF in the catalogue Gaia DR2 (2018). According to these data relative motions and the family of orbits were calculated by the Apparent Motion Parameters (AMP) method (Kiselev and Kiyaeva, 1980), and the best orbit was chosen for the inner pair AB. A perturbation with the period of 11 years was discovered according to Pulkovo observations of the outer pair. The reasons for the perturbation are discussed.

I-shaped bent closed profiles with tubular shelves and calculation of the optimal layout of their composite sections

I-shaped bent closed profiles with tubular shelves are distinguished by a composite section and related to light steel thin-walled structures (LSTWS), which are characterized by high technical and economic indicators and mass demand in industrial and civil construction, which determines the relevance of the development of their new technical solutions. The aim of the work - to show that the characteristics of LSTWS can be further improved by forming profiles, combining straight and round outlines of closed and open circuits in a composite section. Methods. New technical solution, the originality of which is confirmed by patent examination, has been developed through experimental design and optimization and design calculations of I-shaped profiles. The calculation of the optimal bending layout of the composite sections of I-shaped profiles of horizontal billets from sheet blanks, identical and unequal in thickness, including bisteel modifications, is made. Results. The I-shaped bent closed profiles consists of two tubular shelves and one wall of double thickness. For its manufacture without welded, bolted or riveted joints, the outer pair and inner pair blanks are made along the entire length with serrated longitudinal edges, the teeth of which are staggered relative to each other and mutually bent in grooves after closing a bent profile along its shelves. The bends of the gear mounts increase the collapse thickness, provide an increase in the local stability and shear strength of the thin-walled elements, and also allow not to reduce the design sections. The calculation of the optimal layout of I-shaped profiles horizontal bend for bending showed that its strength is maximum when the ratio of the width and height of 1/5.2 and equal thicknesses of shelves and walls.

Multifrequency study of a double–double radio galaxy J0028+0035

ABSTRACT We report the discovery of a double–double radio source (DDRS) J0028+0035. We observed it with LOFAR, GMRT, and the VLA. By combining our observational data with those from the literature, we gathered an appreciable set of radio flux density measurements covering the range from 74 MHz to 14 GHz. This enabled us to carry out an extensive review of physical properties of the source and its dynamical evolution analysis. In particular, we found that, while the age of the large-scale outer lobes is about 245 Myr, the renewal of the jet activity, which is directly responsible for the double–double structure, took place only about 3.6 Myr ago after about 11 Myr long period of quiescence. Another important property typical for DDRSs and also present here is that the injection spectral indices for the inner and the outer pair of lobes are similar. The jet powers in J0028+0035 are similar too. Both these circumstances support our inference that it is, in fact, a DDRS which was not recognized as such so far because of the presence of a coincident compact object close to the inner double so that the centre of J0028+0035 is apparently a triple.

Occupational safety of pressurized intraperitoneal aerosol chemotherapy (PIPAC)

BackgroundPressurized intraperitoneal aerosol chemotherapy (PIPAC) has emerged as a novel method to treat extensive, small volume peritoneal metastases. The clinical use of chemotherapy containing aerosols represents a potential occupational health hazard. We report the results of toxicological analysis during the first two clinical PIPAC procedures performed at Ghent University Hospital.MethodsAfter extensive preparation and in vitro testing, two patients were treated with PIPAC: the first using doxorubicin (2.86 mg in 51.43 mL) and cisplatin (14.28 mg in 164.3 mL), the second using oxaliplatin (182.10 mg in 186.42 mL). A standardized safety checklist was developed and used. Aerosol delivery was combined with electrostatic precipitation (ePIPAC). The following samples were obtained at several time points and locations: environmental air, floor surface wipes, surgeon’s gloves, surgeon’s hand wipes, circuit filters, and fluid from the water seal collection chamber container placed along the closed aerosol waste evacuating line. Platinum concentration was measured in these samples using voltammetry. Sample collection and analysis were performed by an independent external laboratory.ResultsPlatinum was not detected on the four floor locations after both procedures (detection limit 0.02 ng/cm2). Similarly, no platinum was detected in environmental air during both PIPACs at the surgeon’s or anesthesiologist’s position (detection limit 4.0–27 ng/m3). No platinum contamination was detected on the hands, outer pair of gloves, or inner pair of gloves of the surgeon (detection limit 70 and 50 ng respectively). Platinum was not detected on the filters and in the air-seal container liquid.ConclusionsWith adequate preparation and precautions, a clinical PIPAC program can be established without measurable chemotherapy exposure to the operating room environment or healthcare workers.

Sealed and Delivered

Engineers at A.W Chesterton Co., Stoneham, MA, applied computational fluid dynamics (CFD) to a new model of their heavy-duty cartridge dual seal Chesterton's dual seal consists of two pairs of seal rings. Mechanical seals are widely used to prevent leakage from fluid-handling equipment such as centrifugal pumps and mixers. Outer pair rotates with the shaft; inner pairs are fixed and contain a channel for the barrier fluid. The seal confines process fluids to the areas on the left. Taper is visible along the lower edge of the inner seal rings and on the corresponding surface of the shaft covering. CFD images described in the article depict the axial circulation of the seal's barrier fluid for a typical untapered seal design and the improved circulation resulting from the tapered surface design. The change in flow patterns results in an improvement in heat removal, from 0.7 to 1.1 kW. In order to validate the accuracy of the CFD results, physical experiments were conducted in Chesterton's seal test laboratory, using a variety of flow rates, rotation speeds, and fluids. The seals that do incorporate the innovative design have performed well in the field, operating at cooler temperatures that should result in seal life at least 30 percent longer,

M87 and the X-Ray Emission from Compact Objects

M87 (Virgo A, 3C274) has been observed at 5 GHz with the Cambridge One-Mile telescope, with a resolution of 6.5 arc sec. These observations do not include the extensive halo but show that the central region of the source consists of at least three components. The central of the components is unresolved and appears to coincide with the optical nucleus, the outer pair extending from a point about 5 arc sec south of the optical nucleus. These components are unresolved perpendicular to their extension axes. The north preceding component is related to the optical jet but is more extended.

Subsidiary Components of the Flagella of Chlamydomonas Reinhardii

Some subsidiary components of flagella from the alga Chlamydomonas reinhardii have been studied in the electron microscope using frayed and partially dispersed material, negatively stained. In all, 5 distinct subsidiary structures have been observed, 3 of which are associated with the 9 pairs of outer tubules and 2 with the central pair of tubules. 1. Radial spokes, about 33 nm long and 5 nm in diameter, are attached at right angles to the A tubule of each outer pair and extend into the lumen of the flagellum in the direction of the central pair of tubules, but do not reach them. The spokes usually occur in pairs along the length of each A tubule. The interval between pairs is about 70 nm and that between the 2 members of each pair about 30 nm. 2. ‘Secondary fibres’. The distal end of each spoke terminates in a hammerhead-like attachment some 10-20 nm by 5 nm with its axis parallel to the long axis of the flagellum. These hammerhead attachments are now identified with the so-called ‘secondary fibres’ previously deduced from micrographs of embedded and sectioned material. There is no evidence from the present work of a continuous secondary fibre throughout the length of the flagellum. 3. Side arms are found attached to the A tubule of each outer pair. These arms, which occur in pairs, are roughly at right angles to the radial spokes which are also attached to the A tubules. The side arm material is distributed along the tubule at regular intervals of about 14 nm. 4. The chemically more stable centre tubule has 2 longitudinal rows of projections, each projection being about 18 nm long with a repeat distance of about 16 nm. 5. Occasionally, on the chemically less stable centre tubule, there is observed one row of projections which are somewhat similar to those on the other tubule. New information has made it possible to reinterpret earlier work and to present a 3-dimensional picture of the external flagellum and its parts.

The neuroendocrine organs in adult Noctuidae

A detailed study of the innervation of the neuroendocrine organs in eight species of Noctuidae has revealed a previously undescribed network of serves. A dorsal branch of the outer pair of nerves connecting the protocerebrum with the corpora cardiaca bears fine nerves extending to the ocellar, antennal, and optic nerves and to the orbital setae. A distinct ventrally directed nerve arising from each corpus cardiacum has branches extending to the optic, maxillary, and palpal nerve and lateral orbital setae. The possible significance of these nerves is discussed in the context of known endocrine functions.