Rewriting the check of 8-rewritability for A5A_5

The group $G$ is called $n$-rewritable for $n>1$, if for each sequence of $n$ elements $x_1, x_2, \dots, x_n \in G$ there exists a non-identity permutation $\sigma \in S_n$ such that $x_1 x_2 \cdots x_n = x_{\sigma(1)} x_{\sigma(2)} \cdots x_{\sigma(n)}$. Using computers, Blyth and Robinson (1990) verified that the alternating group $A_5$ is 8-rewritable. We report on an independent verification of this statement using the computational algebra system GAP, and compare the performance of our sequential and parallel code with the original one.Comment: 5 page

Associate inverse subsemigroups of regular semigroups

By an associate inverse subsemigroup of a regular semigroup S we mean a subsemigroup T of S containing a least associate of each x ∈ S, in relation to the natural partial order ≤S. We describe the structure of a regular semigroup with an associate inverse subsemigroup, satisfying two natural conditions. As a articular application, we obtain the structure of regular semigroups with an associate subgroup with medial identity element.Fundação para a Ciência e a Tecnologia (FCT

Some observations on the ray Himantura marginatus (Blyth) from the Gulf of Mannar

A detailed description of Himantura marginatus (Blyth) based on two large specimens from the Gulf of Mannar is given

Oscillatory oblique stagnation-point flow toward a plane wall

Two-dimensional oscillatory oblique stagnation-point flow toward a plane wall is investigated. The problem is a eneralisation of the steady oblique stagnation-point flow examined by previous workers. Far from the wall, the flow is composed of an irrotational orthogonal stagnation-point flow with a time-periodic strength, a simple shear flow of constant vorticity, and a time-periodic uniform stream. An exact solution of the Navier-Stokes equations is sought for which the flow streamfunction depends linearly on the coordinate parallel to the wall. The problem formulation reduces to a coupled pair of partial differential equations in time and one spatial variable. The first equation describes the oscillatory orthogonal stagnation-point flow discussed by previous workers. The second equation, which couples to the first, describes the oblique component of the flow. A description of the flow velocity field, the instantaneous streamlines, and the particle paths is sought through numerical solutions of the governing equations and via asymptotic analysis

UK donor registries

Fertility services have been formally regulated in the UK since 1991, following implementation of the Human Fertilisation and Embryology Act 1990 (“The Act”). The Act established a statutory regulatory agency, the Human Fertilisation and Embryology Authority (HFEA), whose responsibilities include licensing certain forms of fertility treatment and to maintain a register of information (s31). The register includes details relating to donors, recipients of donated gametes and embryos, and children born as a result of all donor procedures provided by a licensed treatment centr

Various Gallus varius hybrids: variation in junglefowl hybrids and Darwin's interest in them

Hybrids between Green Junglefowl Gallus varius and domestic fowl G. gallus domesticus confused several 19th-century ornithologists. The plumage of these hybrids is so unlike the colours and patterns of either of the parent species that they were considered to be distinct species: G. aeneusTemminck, 1825; G. temminckiiGray, 1849; and G. violaceusKelsall, 1891. Darwin wanted to understand if G. aeneus and G. temminckii were hybrids or species, as part of his research on the origin of the domestic chicken. His view was that all domesticated fowl have a single wild ancestor, Red Junglefowl G. gallus (formerly G. bankiva). A hybrid specimen now present in the bird collection of the Natural History Museum at Tring played an important role in Darwin's reasoning and, although the conclusions he drew from this specimen were incorrect, his single-ancestor origin theory for domesticated fowl stands. ‘These hybrids were at one time thought to be specifically distinct, and were named G. aeneus. Mr. Blyth and others believe that the G. Temminckii is a similar hybrid' (Darwin 1868a: 234–235).© 2019 The Authors; This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published pdf

Breeding season of the Endangered White (Umbrella) Cockatoo, and possible competition for nest holes with Blyth’s (Papuan) Hornbill in North Maluku, Indonesia

The White Cockatoo Cacatua alba is endemic to the North Molucca islands and is considered Endangered mostly due to unsustainable levels of trapping for the pet trade. Little is known about its breeding biology in the wild, except that it nests in tall trees during the early part of the year. We made brief observations of two active nests of White Cockatoos on Halmahera and another on Ternate in February and March 2014, and estimate the egg laying dates of two of these nests as mid-October and mid-November. Combined with other data, the breeding season appears to extend from October to May or June. All three nests were visited by Blyth’s Hornbills Rhyticeros plicatus, a species which occurs throughout North Maluku, as well as New Guinea. One nest was subsequently abandoned. In September and November 2014, we observed two active nest cavities of hornbills, one of which was inspected by a cockatoo, and the other, approached closely by cockatoos. Both hornbill nests were reported to have been used previously by White Cockatoos, suggesting that the two species may either share or compete for the same nest cavities. Sharing of cavities may be facilitated by partly non-overlapping breeding seasons, as Blyth’s Hornbill reportedly lays eggs from August to October in the region. However, as the nest cycle of both species is c.4 months, it is possible that early nesting pairs of one species may attempt to usurp nest cavities occupied by the other species. The potential for nest competition may be exacerbated on small islands where deforestation has reduced the number of nest cavities available for hole-nesting species

What Munn Missed: The Queensland Schools of Arts

American Librarian Ralph Munn\u27s historic tour of Australian libraries in 1934 is well documented. Along with Ernest Pitt, Chief Librarian of the State Library of Victoria, he spent nearly ten weeks travelling from Sydney and back again, visiting libraries in all the state capitals and many regional towns throughout the country. Munn\u27s trip was funded by the Carnegie Corporation of New York, which was then, through its Dominions fund, turning attention to philanthropic opportunities in the Antipodes. The resulting report, Australian Libraries: A Survey of Conditions and Suggestions for their Improvement (commonly referred to as the Munn-Pitt Report) is often credited with initiating the public library movement in Australia. [excerpt

Consumed: stilled lives - Blyth Gallery

Consumed: Stilled Lives plays with the traditional concept of still-life painting, which grew in popularity in the 16th and 17th centuries. Often featuring silver plates, ornate glassware and expensive foodstuffs such as shellfish and exotic fruit, still life paintings became a fashionable way for the Dutch and Flemish to illustrate their wealth. When interpreted using emblematic symbolism the paintings represent a conflicting relation with material wealth. In response to this reading Woolley produces still-life objects that suggest contradictory relationships to contemporary consumer culture. Drawing on both definitions of the term ‘consume’ (to ingest and to purchase) she uses food still-life photography to represent different characters and positions in relation to capitalist society. What we eat and how we eat are symbols of our wider consumer habits. We are what we consume. In addition to photographs and installation this exhibition presents a series of still life objects installed in vitrines. The Celebrate installations suggest the conviviality of a feast but the materials used to make the food disrupt this reading. The objects were produced in response to research into the visualisation of food in eating disorders. Food is imagined to be drained of colour and aroma to help suppress desire. The food is inedible, eradicating its value as food. In the white installation (objects produced in 2012 with supported by a training grant from the Arts Council of Wales), the food is made of the same porcelain as the containers, raising the food to the status of a crafted and delicate object. The grey party food is made of concrete, a common, inexpensive material. The black banquet is made from plastic, material that will not break-down, it is indigestible. The different materials evoke the shifting status of food in the lives of eating disorder sufferers, in turn object of disgust and obsession. Two new installations ‘Barmecide Feast’ devised for the exhibition at Blyth Gallery, are named after Barmecide, a prince in Arabian Nights. Barmecide invites a beggar to a feast, but serves only imaginary food. The beggar plays along, acting as though he were intoxicated by the imaginary wine and hitting the host during a drunken brawl. Eventually the beggar is rewarded with real food. The Barmecide feast has become a name for situations, in which promises are made but not delivered and acts of generosity that are no more than illusions. In the installations the illusion of plenitude and extravagance is undermined by the material of the food. The overabundance of newspaper headlines are intended to leave an unpleasant taste in the mouth, and invoke ideas of food insecurity