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We have created an up-to-date catalogue of 214 brown dwarfs (BDs) in binaries with P < 104 d. This allows us to examine the population statistics of the BD desert. We searched Gaia third data release (DR3) non-single star (NSS) results for orbital inclinations of BD candidates, deriving 12 new masses. Three remain as desert BDs whereas nine candidates are found to be low-mass stars. We improved the radial velocity (RV) solutions for three previously studied BD candidates. A further 19 BD masses with periods less than ∼1200 d were identified in the DR3 binary_masses data base. We confirm a valley in the mass distribution with a minimum around 30–35 Mjup, and find that periods <100 d are still underpopulated in comparison with longer periods. The updated mass and eccentricity distribution of BDs still shows a marginally statistically significant split into high- and low-mass BD populations. This hints at two different parent distributions, and two potential origins – either akin to planetary formation, or stellar. There are no low-eccentricity BDs at periods around 100 d. The mass–metallicity distribution of BDs indicates that core accretion is not the dominant formation mechanism for BDs as they do not follow the same trends that giant exoplanets do with metallicity. We identify a diagonal envelope bounding the Gaia BDs in the mass–period plane due to the detection thresholds of the currently available NSS solutions from 34 months of data. [ABSTRACT FROM AUTHOR]

We present additional HARPS radial velocity observations of the highly eccentric (e ∼ 0.6) binary system DMPP-3AB, which comprises a K0V primary and a low-mass companion at the hydrogen burning limit. The binary has a 507 d orbital period and a 1.2 au semimajor axis. The primary component harbours a known 2.2 M⊕ planet, DMPP-3A b, with a 6.67-d orbit. New HARPS measurements constrain periastron passage for the binary orbit and add further integrity to previously derived solutions for both companion and planet orbits. Gaia astrometry independently confirms the binary orbit and establishes the inclination of the binary is 63.89 ± 0.78°. We performed dynamical simulations that establish that the previously identified ∼800 d RV signal cannot be attributed to an orbiting body. The additional observations, a deviation from strict periodicity, and our new analyses of activity indicators suggest the ∼800 d signal is caused by stellar activity. We conclude that there may be long-period planet 'detections' in other systems, which are similar misinterpreted stellar activity artefacts. Without the unusual eccentric binary companion to the planet-hosting star, we could have accepted the ∼800 d signal as a probable planet. Further monitoring of DMPP-3 will reveal which signatures can be used to most efficiently identify these imposters. We also report a threshold detection (0.2 per cent FAP) of a ∼2.26 d periodicity in the RVs, potentially attributed to an Earth-mass S-type planet interior to DMPP-3A b. [ABSTRACT FROM AUTHOR]

With the exception of Henry Pelling, labour historians have found little positive in the role played by Henry Hyde Champion (18597–1928) in the early socialist movement, and have generally represented his motives as suspect. Tracing his political career from his ‘conversion’ to socialism in 1882 to his departure for Australia in 1894, this article shows how Champion's personal and class characteristics exacerbated the distrust that has always been felt in the labour movement towards would-be leaders with no roots in the working class. Although he was a hard-working publisher and journalist, he represented himself as ‘one of the idle classes’; in his speech, dress, manners, and tastes, he was the epitome of the officer and gentleman; and he saw himself as leading people inferior to himself. He did establish a degree of rapport with some leaders of working-class origin, notably John Burns, Tom Mann and Keir Hardie, who did not doubt his sincerity even when they were critical of his actions, but he was always an outsider in the socialist movement, his isolation being further increased by his compulsive desire for action, and his willingness to act alone. [ABSTRACT FROM PUBLISHER]

Presents a continuation of lists of selected dissertations begun in the July 1970 issue of the journal "Western Historical Quarterly." "Raised Field Landscapes of Native North America," by William Gustav Gartner; "Carey McWilliams and the Question of Cultural Citizenship in the 1940s," by Maria Jose Canelo; "The Role of Ideology in the Growth, Establishment, and Decline of the Black Panther Party: 1966 to 1982," by Paul Alkebulan.

Presents a list of dissertations about western history. "Mexican Immigrant Family Farms in the California Strawberry Industry," by Teresa Figueroa Sanchez; "The Morning After the Gold Rush: Prentice Mulford and the American Dream," by Enoch Anderson; "Shaping the Shoreline: Environment, Society, and Culture in Monterey, California," by Connie Young Chiang.

Analyzes the potential magnetic field of AB Doradism. Comparison of the Zeeman and Doppler images; Calculation of the azimuthal component of the corresponding potential field; Application of cross-correlation differentiation between potential and observed azimuthal field distributions.

Presents several letters to the editor. Information regarding the social values; Discussion on the issue of manuscripts of social work; Insight into the sleep therapy.

The 2017–2018 North American influenza season caused more hospitalizations and deaths than any year since the 2009 H1N1 pandemic. The majority of recorded influenza infections were caused by A(H3N2) viruses, with most of the virus's North American diversity falling into the A2 clade. Within A2, we observe a subclade which we call A2/re that rose to comprise almost 70 per cent of A(H3N2) viruses circulating in North America by early 2018. Unlike most fast-growing clades, however, A2/re contains no amino acid substitutions in the hemagglutinin (HA) segment. Moreover, hemagglutination inhibition assays did not suggest substantial antigenic differences between A2/re viruses and viruses sampled during the 2016–2017 season. Rather, we observe that the A2/re clade was the result of a reassortment event that occurred in late 2016 or early 2017 and involved the combination of the HA and PB1 segments of an A2 virus with neuraminidase (NA) and other segments a virus from the clade A1b. The success of this clade shows the need for antigenic analysis that targets NA in addition to HA. Our results illustrate the potential for non-HA drivers of viral success and necessitate the need for more thorough tracking of full viral genomes to better understand the dynamics of influenza epidemics. [ABSTRACT FROM AUTHOR]