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Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions.
The PHENIX collaboration presents first measurements of low-momentum (0.41 GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5 GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield
A defect in myoblast fusion underlies Carey-Fineman-Ziter syndrome
Multinucleate cellular syncytial formation is a hallmark of skeletal muscle differentiation. Myomaker, encoded by Mymk (Tmem8c), is a well-conserved plasma membrane protein required for myoblast fusion to form multinucleated myotubes in mouse, chick, and zebrafish. Here, we report that autosomal recessive mutations in MYMK (OMIM 615345) cause Carey-Fineman-Ziter syndrome in humans (CFZS; OMIM 254940) by reducing but not eliminating MYMK function. We characterize MYMK-CFZS as a congenital myopathy with marked facial weakness and additional clinical and pathologic features that distinguish it from other congenital neuromuscular syndromes. We show that a heterologous cell fusion assay in vitro and allelic complementation experiments in mymk knockdown and mymk insT/insT zebrafish in vivo can differentiate between MYMK wild type, hypomorphic and null alleles. Collectively, these data establish that MYMK activity is necessary for normal muscle development and maintenance in humans, and expand the spectrum of congenital myopathies to include cell-cell fusion deficits
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
Effect of Playing Video Games on Laparoscopic Skills Performance: A Systematic Review
Background and Purpose: the advances in both video games and minimally invasive surgery have
allowed many to consider the potential positive relationship between the
two. This review aims to evaluate outcomes of studies that investigated
the correlation between video game skills and performance in
laparoscopic surgery.Methods: a systematic search was conducted on PubMed/Medline and EMBASE
databases for the MeSH terms and keywords including “video games and
laparoscopy,” “computer games and laparoscopy,” “Xbox and laparoscopy,”
“Nintendo Wii and laparoscopy,” and “PlayStation and laparoscopy.”
Cohort, case reports, letters, editorials, bulletins, and reviews were
excluded. Studies in English, with task performance as primary outcome,
were included. The search period for this review was 1950 to December
2014.Results: there were 57 abstracts identified: 4 of these were found to be
duplicates; 32 were found to be nonrelevant to the research question.
Overall, 21 full texts were assessed; 15 were excluded according to the
Medical Education Research Study Quality Instrument quality assessment
criteria. The five studies included in this review were randomized
controlled trials. Playing video games was found to reduce error in two
studies (P 0.002 and P 0.045). For the same studies,
however, several other metrics assessed were not significantly different
between the control and intervention group. One study showed a decrease
in the time for the group that played video games (P 0.037) for
one of two laparoscopic tasks performed. In the same study, however,
when the groups were reversed (initial control group became intervention
and vice versa), a difference was not demonstrated (P for peg transfer 1 – 0.465, P
for cobra robe – 0.185). Finally, two further studies found no
statistical difference between the game playing group and the control
group's performance.Conclusion: there is a very limited amount of evidence to support that the use of video games enhances surgical simulation performance.</p
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