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Properties of symmetric cubic graphs are described via their rigid cells, which are maximal connected subgraphs fixed pointwise by some involutory automorphism of the graph. This paper completes the description of rigid cells and the corresponding involutions for each of the 17 'action types' of symmetric cubic graphs. [ABSTRACT FROM AUTHOR]

Abstract: In a paper in 1982, Said Sidki defined a 2‐parameter family of finitely presented groups Y ( m , n ) that generalise the Carmichael presentation for a finite alternating group satisfied by its generating 3‐cycles ( 1 , 2 , t ) for t ⩾ 3. For m ⩾ 2 and n ⩾ 2, the group Y ( m , n ) is the abstract group generated by elements a 1 , a 2 , ⋯ , a m subject to the defining relations a i n = 1 for 1 ⩽ i ⩽ m and ( a i k a j k ) 2 = 1 for 1 ⩽ i < j ⩽ m and 1 ⩽ k ⩽ [ n 2 ]. Sidki investigated the structure of various subfamilies of these groups, for small values of m or n, and has conjectured that they are all finite. Sidki's conjecture remains open. In this paper it is shown that for all m ⩾ 3, the group Y ( m , 6 ) is finite, and is isomorphic to a semi‐direct product of an elementary abelian 2‐group of order 2 m ( m + 3 ) / 2 by Y ( m , 3 ) ≅ A m + 2. Also we exploit a computation for the group Y ( 3 , 8 ) to prove that Y ( m , 8 ) is a finite 2‐group, for all m. [ABSTRACT FROM AUTHOR]

As part of further investigations into three linked haemorrhagic fever with renal syndrome (HFRS) cases in Wales and England, 21 rats from a breeding colony in Cherwell, and three rats from a household in Cheltenham were screened for hantavirus. Hantavirus RNA was detected in either the lungs and/or kidney of 17/21 (81%) of the Cherwell rats tested, higher than previously detected by blood testing alone (7/21, 33%), and in the kidneys of all three Cheltenham rats. The partial L gene sequences obtained from 10 of the Cherwell rats and the three Cheltenham rats were identical to each other and the previously reported UK Cherwell strain. Seoul hantavirus (SEOV) RNA was detected in the heart, kidney, lung, salivary gland and spleen (but not in the liver) of an individual rat from the Cherwell colony suspected of being the source of SEOV. Serum from 20/20 of the Cherwell rats and two associated HFRS cases had high levels of SEOV-specific antibodies (by virus neutralisation). The high prevalence of SEOV in both sites and the moderately severe disease in the pet rat owners suggest that SEOV in pet rats poses a greater public health risk than previously considered. [ABSTRACT FROM AUTHOR]

Passive surveillance for lyssaviruses in UK bats has been ongoing since 1987 and has identified 13 cases of EBLV-2 from a single species; Myotis daubentonii. No other lyssavirus species has been detected. Between 2005 and 2015, 10 656 bats were submitted, representing 18 species, creating a spatially and temporally uneven sample of British bat fauna. Uniquely, three UK cases originate from a roost at Stokesay Castle in Shropshire, England, where daily checks for grounded and dead bats are undertaken and bat carcasses have been submitted for testing since 2007. Twenty per cent of Daubenton's bats submitted from Stokesay Castle since surveillance began, have tested positive for EBLV-2. Phylogenetic analysis reveals geographical clustering of UK viruses. Isolates from Stokesay Castle are more closely related to one another than to viruses from other regions. Daubenton's bats from Stokesay Castle represent a unique opportunity to study a natural population that appears to maintain EBLV-2 infection and may represent endemic infection at this site. Although the risk to public health from EBLV-2 is low, consequences of infection are severe and effective communication on the need for prompt post-exposure prophylaxis for anyone that has been bitten by a bat is essential. [ABSTRACT FROM AUTHOR]

Abstract polytopes are combinatorial structures obeying certain axioms that generalise both classical convex geometric polytopes (like the Platonic solids) and maps on surfaces (such as Klein's quartic). Every automorphism (symmetry) of an abstract polytope [ABSTRACT FROM AUTHOR]

Background: The recommended screening of rabies in 'suspect' animal cases involves testing fresh brain tissue. The preservation of fresh tissue however can be difficult under field conditions and formalin fixation provides a simple alternative that may allow a confirmatory diagnosis. The occurrence and location of histopathological changes and immunohistochemical (IHC) labelling for rabies in formalin fixed paraffin embedded (FFPE) canine brain is described in samples from 57 rabies suspect cases from Sri-Lanka. The presence of Negri bodies and immunohistochemical detection of rabies virus antigen were evaluated in the cortex, hippocampus, cerebellum and brainstem. The effect of autolysis and artefactual degeneration of the tissue was also assessed. Results: Rabies was confirmed in 53 of 57 (93%) cases by IHC. IHC labelling was statistically more abundant in the brainstem. Negri bodies were observed in 32 of 53 (60.4%) of the positive cases. Although tissue degradation had no effect on IHC diagnosis, it was associated with an inability to detect Negri bodies. In 13 cases, a confirmatory Polymerase chain reaction (PCR) testing for rabies virus RNA was undertaken by extracting RNA from fresh frozen tissue, and also attempted using FFPE samples. PCR detection using fresh frozen samples was in agreement with the IHC results. The PCR method from FFPE tissues was suitable for control material but unsuccessful in our field cases. Conclusions: Histopathological examination of the brain is essential to define the differential diagnoses of behaviour modifying conditions in rabies virus negative cases, but it is unreliable as the sole method for rabies diagnosis, particularly where artefactual change has occurred. Formalin fixation and paraffin embedding does not prevent detection of rabies virus via IHC labelling even where artefactual degeneration has occurred. This could represent a pragmatic secondary assay for rabies diagnosis in the field because formalin fixation can prevent sample degeneration. The brain stem was shown to be the site with most viral immunoreactivity; supporting recommended sampling protocols in favour of improved necropsy safety in the field. PCR testing of formalin fixed tissue may be successful in certain circumstances as an alternative test. [ABSTRACT FROM AUTHOR]

We prove the existence of infinitely many orientably-regular but chiral maps of every given hyperbolic type {m, k}, by constructing base examples from suitable permutation representations of the ordinary (2, k,m) triangle group, and then taking abelian p-covers. The base examples also help to prove that for every pair (k,m) of integers with 1/k + 1/m ⩽ 1/2, there exist infinitely many regular and infinitely many orientably-regular but chiral maps of type {m, k}, each with the property that both the map and its dual have simple underlying graph. [ABSTRACT FROM AUTHOR]

An orientably-regular map M is a 2-cell embedding of a connected graph in a closed, orientable surface, with the property that the group Aut엯M of all orientation-preserving automorphisms acts transitively on the arcs of M. If Aut엯M contains a subgroup A that acts regularly on the vertex set, then M is called a regular Cayley map for A. In this paper, we answer a question of recent interest by providing a complete classification of the regular Cayley maps for the cyclic group Cn, for every possible order n. This is the first such classification for any infinite family of groups. The approach used is entirely algebraic and does not involve skew morphisms (but leads to a classification of all skew morphisms which have an orbit that is closed under inverses and generates the group). A key step is the use of a generalisation by Conder and Isaacs (2004) of Ito's theorem on group factorisations, to help determine the isomorphism type of Aut엯M. This group is shown to be a cyclic extension of a cyclic or dihedral group, dependent on n and a single parameter r, which is a unit modulo n that satisfies technical number-theoretic conditions. For each n, we enumerate all such r, and then in terms of r, we find the valence and covalence of the map, and determine whether or not the map is reflexible, and whether it has a representation as a balanced, anti-balanced or t-balanced regular Cayley map. [ABSTRACT FROM AUTHOR]

Bat rabies cases in Europe are principally attributed to two lyssaviruses, namely European bat lyssavirus type 1 (EBLV-1) and European bat lyssavirus type 2 (EBLV-2). Between 1977 and 2011, 961 cases of bat rabies were reported to Rabies Bulletin Europe, with the vast majority (>97%) being attributed to EBLV-1. There have been 25 suspected cases of EBLV-2, of which 22 have been confirmed. In addition, two single isolations of unique lyssaviruses from European insectivorous bats were reported in south-west Russia in 2002 (West Caucasian bat virus) and in Germany in 2010 (Bokeloh bat lyssavirus). In this review, we present phylogenetic analyses of the EBLV-1 and EBLV-2 using partial nucleoprotein (N) gene sequences. In particular, we have analysed all EBLV-2 cases for which viral sequences (N gene, 400 nucleotides) are available ( n = 21). Oropharyngeal swabs collected from two healthy Myotis daubentonii during active surveillance programmes in Scotland and Switzerland also yielded viral RNA (EBLV-2). Despite the relatively low number of EBLV-2 cases, a surprisingly large amount of anomalous data has been published in the scientific literature and Genbank, which we have collated and clarified. For both viruses, geographical relationships are clearly defined on the phylogenetic analysis. Whilst there is no clear chronological clustering for either virus, there is some evidence for host specific relationships, particularly for EBLV-1 where more host variation has been observed. Further genomic regions must be studied, in particular for EBLV-1 isolates from Spain and the EBLV-2 isolates to provide support for the existence of sublineages. [ABSTRACT FROM AUTHOR]

Rabies is endemic throughout most of Asia, with the majority of human cases transmitted by domestic dogs ( Canis familiaris). Here, we report a case of rabies in a 12-year-old girl in the Lalitpur district of Nepal that might have been prevented by better public awareness and timely post-exposure prophylaxis. Molecular characterization of the virus showed 100% identity over a partial nucleoprotein gene sequence to previous isolates from Nepal belonging to the 'arctic-like' lineage of rabies virus. Sequence analysis of both partial nucleoprotein and glycoprotein genes showed differences in consensus sequence after passage in vitro but not after passage in vivo. [ABSTRACT FROM AUTHOR]

n orientably-regular map is a 2-cell embedding of a connected graph or multigraph into an orientable surface, such that the group of all orientation-preserving automorphisms of the embedding has a single orbit on the set of all arcs (incident vertex-edge pairs). Such embeddings of the n-dimensional cubes Q were classified for all odd n by Du, Kwak and Nedela in 2005, and in 2007, Jing Xu proved that for n=2 m where m is odd, they are precisely the embeddings constructed by Kwon in 2004. Here, we give a classification of orientably-regular embeddings of Q for all n. In particular, we show that for all even n (=2 m), these embeddings are in one-to-one correspondence with elements σ of order 1 or 2 in the symmetric group S such that σ fixes n, preserves the set of all pairs B={ i, i+ m} for 1≤ i≤ m, and induces the same permutation on this set as the permutation B ↦ B for some additive bijection f:ℤ→ℤ. We also give formulae for the numbers of embeddings that are reflexible and chiral, respectively, showing that the ratio of reflexible to chiral embeddings tends to zero for large even n. [ABSTRACT FROM AUTHOR]

A 37-year-old woman was admitted to hospital and over the next 5 days developed a progressive encephalitis. Nuchal skin biopsy, analyzed using a Rabies TaqMan© PCR, demonstrated rabies virus RNA. She had a history in keeping with exposure to rabies whilst in South Africa, but had not received pre- or post-exposure prophylaxis. She was treated with a therapeutic coma according to the 'Milwaukee protocol,' which failed to prevent the death of the patient. Rabies virus was isolated from CSF and saliva, and rabies antibody was demonstrated in serum (from day 11 onwards) and cerebrospinal fluid (day 13 onwards). She died on day-35 of hospitalization. Autopsy specimens demonstrated the presence of rabies antigen, viral RNA, and viable rabies virus in the central nervous system. J. Med. Virol. 82:1255-1265, 2010. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

This paper uses combinatorial group theory to help answer some long-standing questions about the genera of orientable surfaces that carry particular kinds of regular maps. By classifying all orientably-regular maps whose automorphism group has order coprime to g-1, where g is the genus, all orientably-regular maps of genus p+1 for p prime are determined. As a consequence, it is shown that orientable surfaces of infinitely many genera carry no regular map that is chiral (ir-reflexible), and that orientable surfaces of infinitely many genera carry no reflexible regular map with simple underlying graph. Another consequence is a simpler proof of the Breda-Nedela-Širáň classification of non-orientable regular maps of Euler characteristic -p where p is prime. [ABSTRACT FROM AUTHOR]

To eradicate rabies in foxes, almost 97 million oral rabies vaccine baits have been distributed in Germany and Austria since 1983 and 1986, respectively. Since 2007, no terrestrial cases have been reported in either country. The most widely used oral rabies vaccine viruses in these countries were SAD (Street Alabama Dufferin) strains, e.g. SAD B19 (53.2%) and SAD P5/88 (44.5%). In this paper, we describe six possible vaccine-virus-associated rabies cases in red foxes ( Vulpes vulpes) detected during post-vaccination surveillance from 2001 to 2006, involving two different vaccines and different batches. Compared to prototypic vaccine strains, full-genome sequencing revealed between 1 and 5 single nucleotide alterations in the L gene in 5 of 6 SAD isolates, resulting in up to two amino acid substitutions. However, experimental infection of juvenile foxes showed that those mutations had no influence on pathogenicity. The cases described here, coming from geographically widely separated regions, do not represent a spatial cluster. More importantly, enhanced surveillance showed that the vaccine viruses involved did not become established in the red fox population. It seems that the number of reported vaccine virus-associated rabies cases is determined predominantly by the intensity of surveillance after the oral rabies vaccination campaign and not by the selection of strains. [ABSTRACT FROM AUTHOR]

Between October 2008 and May 2009, five brain samples from the carcasses of the rare Ethiopian wolf ( Canis simenensis) were submitted for rabies virus testing. Rabies virus was detected in all five samples, and this confirmed that a further outbreak of rabies had occurred within the wolf population in the Bale Mountains of Ethiopia. Sequence comparison of a partial fragment of the nucleoprotein-coding gene demonstrated that all viruses showed 100% sequence identity, suggesting a single introduction of rabies virus. [ABSTRACT FROM AUTHOR]

The article provides information on the study which reveals the sixth case of a European bat lyssavirus type 2 (EBLV-2) positive Daubenton's bat in Shropshire, England since 1996. Researchers noted that the new case from Shropshire represents 4% of all bats submitted for rabies testing that consists of three adult females, three immature females, and one adult male. The said case was investigated after an adult female Daubenton's bat was found at Stokesay Castle on August 12, 2007.

Responds to criticism by Koorland and Nelson in the September 1990 issue of `Exceptional Children.'