3,714 research outputs found
Punctuated Equilibrium in Software Evolution
The approach based on paradigm of self-organized criticality proposed for
experimental investigation and theoretical modelling of software evolution. The
dynamics of modifications studied for three free, open source programs Mozilla,
Free-BSD and Emacs using the data from version control systems. Scaling laws
typical for the self-organization criticality found. The model of software
evolution presenting the natural selection principle is proposed. The results
of numerical and analytical investigation of the model are presented. They are
in a good agreement with the data collected for the real-world software.Comment: 4 pages, LaTeX, 2 Postscript figure
The Wild Turkey in South Dakota
This bulletin provides an extensive look at the wild turkey in South Dakota
Discovering the Elite Hypervolume by Leveraging Interspecies Correlation
Evolution has produced an astonishing diversity of species, each filling a
different niche. Algorithms like MAP-Elites mimic this divergent evolutionary
process to find a set of behaviorally diverse but high-performing solutions,
called the elites. Our key insight is that species in nature often share a
surprisingly large part of their genome, in spite of occupying very different
niches; similarly, the elites are likely to be concentrated in a specific
"elite hypervolume" whose shape is defined by their common features. In this
paper, we first introduce the elite hypervolume concept and propose two metrics
to characterize it: the genotypic spread and the genotypic similarity. We then
introduce a new variation operator, called "directional variation", that
exploits interspecies (or inter-elites) correlations to accelerate the
MAP-Elites algorithm. We demonstrate the effectiveness of this operator in
three problems (a toy function, a redundant robotic arm, and a hexapod robot).Comment: In GECCO 201
Human phosphodiesterase 4D7 (PDE4D7) expression is increased in TMPRSS2-ERG positive primary prostate cancer and independently adds to a reduced risk of post-surgical disease progression
background: There is an acute need to uncover biomarkers that reflect the molecular pathologies, underpinning prostate cancer progression and poor patient outcome. We have previously demonstrated that in prostate cancer cell lines PDE4D7 is downregulated in advanced cases of the disease. To investigate further the prognostic power of PDE4D7 expression during prostate cancer progression and assess how downregulation of this PDE isoform may affect disease outcome, we have examined PDE4D7 expression in physiologically relevant primary human samples.
methods: About 1405 patient samples across 8 publically available qPCR, Affymetrix Exon 1.0 ST arrays and RNA sequencing data sets were screened for PDE4D7 expression. The TMPRSS2-ERG gene rearrangement status of patient samples was determined by transformation of the exon array and RNA seq expression data to robust z-scores followed by the application of a threshold >3 to define a positive TMPRSS2-ERG gene fusion event in a tumour sample.
results: We demonstrate that PDE4D7 expression positively correlates with primary tumour development. We also show a positive association with the highly prostate cancer-specific gene rearrangement between TMPRSS2 and the ETS transcription factor family member ERG. In addition, we find that in primary TMPRSS2-ERG-positive tumours PDE4D7 expression is significantly positively correlated with low-grade disease and a reduced likelihood of progression after primary treatment. Conversely, PDE4D7 transcript levels become significantly decreased in castration resistant prostate cancer (CRPC).
conclusions: We further characterise and add physiological relevance to PDE4D7 as a novel marker that is associated with the development and progression of prostate tumours. We propose that the assessment of PDE4D7 levels may provide a novel, independent predictor of post-surgical disease progression
Disulphide cross-linking of smooth-muscle and non-muscle caldesmon to the C-terminus of actin in reconstituted and native thin filaments
Données préliminaires sur le paludisme humain en zones rurale et sémi-urbaine du département du Nkam (Littoral-Cameroun)
Objectif : Cette étude évalue les connaissances et les pratiques des populations sur le traitement et la prévention du paludisme et détermine la transmission du paludisme en zones rurale et sémi-urbaine du département du Nkam.Méthodologie et résultats : Un questionnaire a été administré aux populations de Bodiman et Yabassi, localités rurale et semi-urbaine, en mai 2015. Les captures de moustiques sur volontaires ont été effectuées à l’intérieur de 7 habitations par site, de juillet à septembre 2015, au rythme de 2 nuits consécutives par mois. L’infectivité des vecteurs a été déterminée par le test ELISA-CSP. 73,17% (n= 513) d’interviewés connaissaient les vecteurs du paludisme alors que seulement 9,46% (n= 63) connaissaient le germe. La moustiquaire était l’outil de prévention le plus utilisé à Bodiman (100%) et Yabassi (38,46%). Le montant mensuellement dépensé par les ménages contre le paludisme s’élevait à 2,31€ et 16,01€ en moyenne, respectivement à Bodiman et Yabassi. La majorité d’interviewés à Bodiman (n= 98 ; %=49,49) et Yabassi (n=198 ; %= 42,31) se rendaient à l’hôpital en cas de paludisme. En outre, 37 833 moustiques dont 35 961 à Bodiman et 1 872 à Yabassi ont été capturés. An. gambiae (81,82%) et An. coluzzii (18,18%) étaient les membres du complexe Gambiae identifiés ; An. coluzzii (59,26%) étant le plus représenté à Yabassi, et An. gambiae (81,82%) à Bodiman. Les indices sporozoïtiques d’An. gambiae s.l. étaient de 0% à Bodiman et de 2,15% à Yabassi.Conclusion et application : L’association de la lutte antilarvaire aux méthodes existantes de lutte antivectorielle par les pouvoirs publics contribuerait à baisser les fortes densités agressives observées à Bodiman de manière à réduire le budget alloué au paludisme par les ménages.Mots-clés : Connaissances, pratiques, transmission, paludisme, Bodiman, Yabassi
PEN: a low energy test of lepton universality
Allowed charged meson decays are characterized by simple dynamics, few
available decay channels, mainly into leptons, and extremely well controlled
radiative and loop corrections. In that sense, pion decays represent a
veritable triumph of the standard model (SM) of elementary particles and
interactions. This relative theoretical simplicity makes charged pion decays a
sensitive means for testing the underlying symmetries and the universality of
weak fermion couplings, as well as for studying pion structure and chiral
dynamics. Even after considerable recent improvements, experimental precision
is lagging far behind that of the theoretical description for pion decays. We
review the current state of experimental study of the pion electronic decay
, or , where the
indicates inclusion and explicit treatment of radiative decay events. We
briefly review the limits on non-SM processes arising from the present level of
experimental precision in decays. Focusing on the PEN
experiment at the Paul Scherrer Institute (PSI), Switzerland, we examine the
prospects for further improvement in the near term.Comment: 11 pages, 5 figures; paper presented at the XIII International
Conference on Heavy Quarks and Leptons, 22-27 May 2016, Blacksburg, Virginia,
US
INTROGRESSION OF COYOTE MITOCHONDRIAL DNA INTO SYMPATRIC NORTH AMERICAN GRAY WOLF POPULATIONS
Mitochondrial DNA (mtDNA) genotypes of gray wolves and coyotes from localities throughout North America were determined using restriction fragment length polymorphisms. Of the 13 genotypes found among the wolves, 7 are clearly of coyote origin, indicating that genetic transfer of coyote mtDNA into wolf populations has occurred through hybridization. The transfer of mtDNA appears unidirectional from coyotes into wolves because no coyotes sampled have a wolf-derived mtDNA genotype. Wolves possessing coyote-derived genotypes are confined to a contiguous geographic region in Minnesota, Ontario, and Quebec, and the frequency of coyote- type mtDNA in these wolf populations is high (\u3e 500%). The ecological history of the hybrid zone suggests that hybridization is taking place in regions where coyotes have only recently become abundant following conversion of forests to farmlands. Dispersing male wolves unable to find conspecific mates may be pairing with female coyotes in deforested areas bordering wolf territories. Our results demonstrate that closely related species of mobile terrestrial vertebrates have the potential for extensive genetic exchange when ecological conditions change suddenly
Wear Minimization for Cuckoo Hashing: How Not to Throw a Lot of Eggs into One Basket
We study wear-leveling techniques for cuckoo hashing, showing that it is
possible to achieve a memory wear bound of after the
insertion of items into a table of size for a suitable constant
using cuckoo hashing. Moreover, we study our cuckoo hashing method empirically,
showing that it significantly improves on the memory wear performance for
classic cuckoo hashing and linear probing in practice.Comment: 13 pages, 1 table, 7 figures; to appear at the 13th Symposium on
Experimental Algorithms (SEA 2014
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