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Myosin-I nomenclature.
We suggest that the vertebrate myosin-I field adopt a common nomenclature system based on the names adopted by the Human Genome Organization (HUGO). At present, the myosin-I nomenclature is very confusing; not only are several systems in use, but several different genes have been given the same name. Despite their faults, we believe that the names adopted by the HUGO nomenclature group for genome annotation are the best compromise, and we recommend universal adoption
Fast shape reconstruction of perfectly conducting cracks by using a multi-frequency topological derivative strategy
This paper concerns a fast, one-step iterative technique of imaging extended
perfectly conducting cracks with Dirichlet boundary condition. In order to
reconstruct the shape of cracks from scattered field data measured at the
boundary, we introduce a topological derivative-based electromagnetic imaging
function operated at several nonzero frequencies. The properties of the imaging
function are carefully analyzed for the configurations of both symmetric and
non-symmetric incident field directions. This analysis explains why the
application of incident fields with symmetric direction operated at multiple
frequencies guarantees a successful reconstruction. Various numerical
simulations with noise-corrupted data are conducted to assess the performance,
effectiveness, robustness, and limitations of the proposed technique.Comment: 17 pages, 27 figure
Dynamics of direct inter-pack encounters in endangered African wild dogs
Aggressive encounters may have important life history consequences due to the potential for injury and death, disease transmission, dispersal opportunities or exclusion from key areas of the home range. Despite this, little is known of their detailed dynamics, mainly due to the difficulties of directly observing encounters in detail. Here, we describe detailed spatial dynamics of inter-pack encounters in African wild dogs (Lycaon pictus), using data from custom-built high-resolution GPS collars in 11 free-ranging packs. On average, each pack encountered another pack approximately every 7 weeks and met each neighbour twice each year. Surprisingly, intruders were more likely to win encounters (winning 78.6% of encounters by remaining closer to the site in the short term). However, intruders did tend to move farther than residents toward their own range core in the short-term (1 h) post-encounter, and if this were used to indicate losing an encounter, then the majority (73.3%) of encounters were won by residents. Surprisingly, relative pack size had little effect on encounter outcome, and injuries were rare (<15% of encounters). These results highlight the difficulty of remotely scoring encounters involving mobile participants away from static defendable food resources. Although inter-pack range overlap was reduced following an encounter, encounter outcome did not seem to drive this, as both packs shifted their ranges post-encounter. Our results indicate that inter-pack encounters may be lower risk than previously suggested and do not appear to influence long-term movement and ranging
Magnetic interactions in iron superconductors: A review
High temperature superconductivity in iron pnictides and chalcogenides
emerges when a magnetic phase is suppressed. The multi-orbital character and
the strength of correlations underlie this complex phenomenology, involving
magnetic softness and anisotropies, with Hund's coupling playing an important
role. We review here the different theoretical approaches used to describe the
magnetic interactions in these systems. We show that taking into account the
orbital degree of freedom allows us to unify in a single phase diagram the main
mechanisms proposed to explain the (\pi,0) order in iron pnictides: the
nesting-driven, the exchange between localized spins, and the Hund induced
magnetic state with orbital differentiation. Comparison of theoretical
estimates and experimental results helps locate the Fe superconductors in the
phase diagram. In addition, orbital physics is crucial to address the magnetic
softness, the doping dependent properties, and the anisotropies.Comment: Invited review article for a focus issue of Comptes Rendus Physique:
26 pages, 10 figures. Revised version, as accepted. Small changes throughout
the text plus new subsection (Sec. IIIE
Determinants of immigration strategies in male crested macaques (Macaca nigra).
Immigration into a new group can produce substantial costs due to resistance from residents, but also reproductive benefits. Whether or not individuals base their immigration strategy on prospective costbenefit ratios remains unknown. We investigated individual immigration decisions in crested macaques, a primate species with a high reproductive skew in favour of high-ranking males. We found two different strategies. Males who achieved low rank in the new group usually immigrated after another male had immigrated within the previous 25 days and achieved high rank. They never got injured but also had low prospective reproductive success. We assume that these males benefitted from immigrating into a destabilized male hierarchy. Males who achieved high rank in the new group usually immigrated independent of previous immigrations. They recieved injuries more frequently and therefore bore immigration costs. They, however, also had higher reproductive success prospects. We conclude that male crested macaques base their immigration strategy on relative fighting ability and thus potential rank in the new group i.e. potential reproductive benefits, as well as potential costs of injury
SIVagm Infection in Wild African Green Monkeys from South Africa: Epidemiology, Natural History, and Evolutionary Considerations
Pathogenesis studies of SIV infection have not been performed to date in wild monkeys due to difficulty in collecting and storing samples on site and the lack of analytical reagents covering the extensive SIV diversity. We performed a large scale study of molecular epidemiology and natural history of SIVagm infection in 225 free-ranging AGMs from multiple locations in South Africa. SIV prevalence (established by sequencing pol, env, and gag) varied dramatically between infant/juvenile (7%) and adult animals (68%) (p<0.0001), and between adult females (78%) and males (57%). Phylogenetic analyses revealed an extensive genetic diversity, including frequent recombination events. Some AGMs harbored epidemiologically linked viruses. Viruses infecting AGMs in the Free State, which are separated from those on the coastal side by the Drakensberg Mountains, formed a separate cluster in the phylogenetic trees; this observation supports a long standing presence of SIV in AGMs, at least from the time of their speciation to their Plio-Pleistocene migration. Specific primers/probes were synthesized based on the pol sequence data and viral loads (VLs) were quantified. VLs were of 104-106 RNA copies/ml, in the range of those observed in experimentally-infected monkeys, validating the experimental approaches in natural hosts. VLs were significantly higher (107-108 RNA copies/ml) in 10 AGMs diagnosed as acutely infected based on SIV seronegativity (Fiebig II), which suggests a very active transmission of SIVagm in the wild. Neither cytokine levels (as biomarkers of immune activation) nor sCD14 levels (a biomarker of microbial translocation) were different between SIV-infected and SIV-uninfected monkeys. This complex algorithm combining sequencing and phylogeny, VL quantification, serology, and testing of surrogate markers of microbial translocation and immune activation permits a systematic investigation of the epidemiology, viral diversity and natural history of SIV infection in wild African natural hosts. © 2013 Ma et al
Heavy and light roles: myosin in the morphogenesis of the heart
Myosin is an essential component of cardiac muscle, from the onset of cardiogenesis through to the adult heart. Although traditionally known for its role in energy transduction and force development, recent studies
suggest that both myosin heavy-chain and myosin lightchain
proteins are required for a correctly formed heart.
Myosins are structural proteins that are not only expressed
from early stages of heart development, but when mutated
in humans they may give rise to congenital heart defects.
This review will discuss the roles of myosin, specifically
with regards to the developing heart. The expression of
each myosin protein will be described, and the effects that
altering expression has on the heart in embryogenesis in
different animal models will be discussed. The human
molecular genetics of the myosins will also be reviewed
Pathogenic copy number variants and SCN1A mutations in patients with intellectual disability and childhood-onset epilepsy
Background Copy number variants (CNVs) have been linked to neurodevelopmental disorders such as intellectual disability (ID), autism, epilepsy and psychiatric disease. There are few studies of CNVs in patients with both ID and epilepsy. Methods We evaluated the range of rare CNVs found in 80 Welsh patients with ID or developmental delay (DD), and childhood-onset epilepsy. We performed molecular cytogenetic testing by single nucleotide polymorphism array or microarray-based comparative genome hybridisation. Results 8.8 % (7/80) of the patients had at least one rare CNVs that was considered to be pathogenic or likely pathogenic. The CNVs involved known disease genes (EHMT1, MBD5 and SCN1A) and imbalances in genomic regions associated with neurodevelopmental disorders (16p11.2, 16p13.11 and 2q13). Prompted by the observation of two deletions disrupting SCN1A we undertook further testing of this gene in selected patients. This led to the identification of four pathogenic SCN1A mutations in our cohort. Conclusions We identified five rare de novo deletions and confirmed the clinical utility of array analysis in patients with ID/DD and childhood-onset epilepsy. This report adds to our clinical understanding of these rare genomic disorders and highlights SCN1A mutations as a cause of ID and epilepsy, which can easily be overlooked in adults
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