2,172 research outputs found
Effect of the Butyrate Prodrug Pivaloyloxymethyl Butyrate (AN9) on a Mouse Model for Spinal Muscular Atrophy.
Spinal muscular atrophy (SMA) is an early-onset motor neuron disease that leads to loss of muscle function. Butyrate (BA)-based compounds markedly improve the survival and motor phenotype of SMA mice. In this study, we examine the protective effects of the BA prodrug pivaloyloxymethyl butyrate (AN9) on the survival of SMNΔ7 SMA mice. Oral administration of AN9 beginning at PND04 almost doubled the average lifespan of SMNΔ7 SMA mice. AN9 treatment also increased the growth rate of SMNΔ7 SMA mice when compared to vehicle-treated SMNΔ7 SMA mice. In conclusion, BA prodrugs like AN9 have ameliorative effects on SMNΔ7 SMA mice
Augmenting Parametric Optimal Ascent Trajectory Modeling with Graph Theory
It has been well documented that decisions made in the early stages of Conceptual and Pre-Conceptual design commit up to 80% of total Life-Cycle Cost (LCC) while engineers know the least about the product they are designing [1]. Once within Preliminary and Detailed design however, making changes to the design becomes far more difficult to enact in both cost and schedule. Primarily this has been due to a lack of detailed data usually uncovered later during the Preliminary and Detailed design phases. In our current budget-constrained environment, making decisions within Conceptual and Pre-Conceptual design which minimize LCC while meeting requirements is paramount to a program's success. Within the arena of launch vehicle design, optimizing the ascent trajectory is critical for minimizing the costs present within such concerns as propellant, aerodynamic, aeroheating, and acceleration loads while meeting requirements such as payload delivered to a desired orbit. In order to optimize the vehicle design its constraints and requirements must be known, however as the design cycle proceeds it is all but inevitable that the conditions will change. Upon that change, the previously optimized trajectory may no longer be optimal, or meet design requirements. The current paradigm for adjusting to these updates is generating point solutions for every change in the design's requirements [2]. This can be a tedious, time-consuming task as changes in virtually any piece of a launch vehicle's design can have a disproportionately large effect on the ascent trajectory, as the solution space of the trajectory optimization problem is both non-linear and multimodal [3]. In addition, an industry standard tool, Program to Optimize Simulated Trajectories (POST), requires an expert analyst to produce simulated trajectories that are feasible and optimal [4]. In a previous publication the authors presented a method for combatting these challenges [5]. In order to bring more detailed information into Conceptual and Pre-Conceptual design, knowledge of the effects originating from changes to the vehicle must be calculated. In order to do this, a model capable of quantitatively describing any vehicle within the entire design space under consideration must be constructed. This model must be based upon analysis of acceptable fidelity, which in this work comes from POST. Design space interrogation can be achieved with surrogate modeling, a parametric, polynomial equation representing a tool. A surrogate model must be informed by data from the tool with enough points to represent the solution space for the chosen number of variables with an acceptable level of error. Therefore, Design Of Experiments (DOE) is used to select points within the design space to maximize information gained on the design space while minimizing number of data points required. To represent a design space with a non-trivial number of variable parameters the number of points required still represent an amount of work which would take an inordinate amount of time via the current paradigm of manual analysis, and so an automated method was developed. The best practices of expert trajectory analysts working within NASA Marshall's Advanced Concepts Office (ACO) were implemented within a tool called multiPOST. These practices include how to use the output data from a previous run of POST to inform the next, determining whether a trajectory solution is feasible from a real-world perspective, and how to handle program execution errors. The tool was then augmented with multiprocessing capability to enable analysis on multiple trajectories simultaneously, allowing throughput to scale with available computational resources. In this update to the previous work the authors discuss issues with the method and solutions
Substructure in the Coma Cluster: Giants vs Dwarfs
The processes that form and shape galaxy clusters, such as infall, mergers
and dynamical relaxation, tend to generate distinguishable differences between
the distributions of a cluster's giant and dwarf galaxies. Thus the dynamics of
dwarf galaxies in a cluster can provide valuable insights into its dynamical
history. With this in mind, we look for differences between the spatial and
velocity distributions of giant (b18) galaxies in the Coma
cluster. Our redshift sample contains new measurements from the 2dF and WYFFOS
spectrographs, making it more complete at faint magnitudes than any previously
studied sample of Coma galaxies. It includes 745 cluster members - 452 giants
and 293 dwarfs. We find that the line-of-sight velocity distribution of the
giants is significantly non-Gaussian, but not that for the dwarfs. A battery of
statistical tests of both the spatial and localised velocity distributions of
the galaxies in our sample finds no strong evidence for differences between the
giant and dwarf populations. These results rule out the cluster as a whole
having moved significantly towards equipartition, and they are consistent with
the cluster having formed via mergers between dynamically-relaxed subclusters.Comment: 23 pages, 6 figures, to appear in Ap
Mobile element insertions are frequent in oesophageal adenocarcinomas and can mislead paired-end sequencing analysis.
BACKGROUND: Mobile elements are active in the human genome, both in the germline and cancers, where they can mutate driver genes. RESULTS: While analysing whole genome paired-end sequencing of oesophageal adenocarcinomas to find genomic rearrangements, we identified three ways in which new mobile element insertions appear in the data, resembling translocation or insertion junctions: inserts where unique sequence has been transduced by an L1 (Long interspersed element 1) mobile element; novel inserts that are confidently, but often incorrectly, mapped by alignment software to L1s or polyA tracts in the reference sequence; and a combination of these two ways, where different sequences within one insert are mapped to different loci. We identified nine unique sequences that were transduced by neighbouring L1s, both L1s in the reference genome and L1s not present in the reference. Many of the resulting inserts were small fragments that include little or no recognisable mobile element sequence. We found 6 loci in the reference genome to which sequence reads from inserts were frequently mapped, probably erroneously, by alignment software: these were either L1 sequence or particularly long polyA runs. Inserts identified from such apparent rearrangement junctions averaged 16 inserts/tumour, range 0-153 insertions in 43 tumours. However, many inserts would not be detected by mapping the sequences to the reference genome, because they do not include sufficient mappable sequence. To estimate total somatic inserts we searched for polyA sequences that were not present in the matched normal or other normals from the same tumour batch, and were not associated with known polymorphisms. Samples of these candidate inserts were verified by sequencing across them or manual inspection of surrounding reads: at least 85 % were somatic and resembled L1-mediated events, most including L1Hs sequence. Approximately 100 such inserts were detected per tumour on average (range zero to approximately 700). CONCLUSIONS: Somatic mobile elements insertions are abundant in these tumours, with over 75 % of cases having a number of novel inserts detected. The inserts create a variety of problems for the interpretation of paired-end sequencing data.Funding
was primarily from Cancer Research UK program grants to RCF and ST
(C14478/A15874 and C14303/A17197), with additional support awarded to
RCF from UK Medical Research Council, NHS National Institute for Health
Research (NIHR), the Experimental Cancer Medicine Centre Network and
the NIHR Cambridge Biomedical Research Centre, and Cancer Research UK
Project grant C1023/A14545 to PAWE. JMJW was funded by a Wellcome
Trust Translational Medicine and Therapeutics grant
Dwarf koa (Desmanthus virgatus)
This is the final version. It was first published by BioMed Central at http://www.biomedcentral.com/1471-2164/16/473.Background: Mobile elements are active in the human genome, both in the germline and cancers, where they can\ud
mutate driver genes.\ud
Results: While analysing whole genome paired-end sequencing of oesophageal adenocarcinomas to find genomic\ud
rearrangements, we identified three ways in which new mobile element insertions appear in the data, resembling\ud
translocation or insertion junctions: inserts where unique sequence has been transduced by an L1 (Long interspersed\ud
element 1) mobile element; novel inserts that are confidently, but often incorrectly, mapped by alignment software to\ud
L1s or polyA tracts in the reference sequence; and a combination of these two ways, where different sequences within\ud
one insert are mapped to different loci. We identified nine unique sequences that were transduced by neighbouring\ud
L1s, both L1s in the reference genome and L1s not present in the reference. Many of the resulting inserts were small\ud
fragments that include little or no recognisable mobile element sequence. We found 6 loci in the reference genome to\ud
which sequence reads from inserts were frequently mapped, probably erroneously, by alignment software: these were\ud
either L1 sequence or particularly long polyA runs. Inserts identified from such apparent rearrangement junctions\ud
averaged 16 inserts/tumour, range 0?153 insertions in 43 tumours. However, many inserts would not be detected by\ud
mapping the sequences to the reference genome, because they do not include sufficient mappable sequence. To\ud
estimate total somatic inserts we searched for polyA sequences that were not present in the matched normal or other\ud
normals from the same tumour batch, and were not associated with known polymorphisms. Samples of these candidate\ud
inserts were verified by sequencing across them or manual inspection of surrounding reads: at least 85 % were somatic\ud
and resembled L1-mediated events, most including L1Hs sequence. Approximately 100 such inserts were detected per\ud
tumour on average (range zero to approximately 700).\ud
Conclusions: Somatic mobile elements insertions are abundant in these tumours, with over 75 % of cases having a\ud
number of novel inserts detected. The inserts create a variety of problems for the interpretation of paired-end\ud
sequencing data.Funding\ud
was primarily from Cancer Research UK program grants to RCF and ST\ud
(C14478/A15874 and C14303/A17197), with additional support awarded to\ud
RCF from UK Medical Research Council, NHS National Institute for Health\ud
Research (NIHR), the Experimental Cancer Medicine Centre Network and\ud
the NIHR Cambridge Biomedical Research Centre, and Cancer Research UK\ud
Project grant C1023/A14545 to PAWE. JMJW was funded by a Wellcome\ud
Trust Translational Medicine and Therapeutics grant
Magazine and reader constructions of 'metrosexuality' and masculinity: a membership categorisation analysis
Since the launch of men's lifestyle magazines in the 1980s, academic literature has predominantly focused on them as a cultural phenomenon arising from entrepreneurial and commercial initiatives and/or as cultural texts that proffer representations of masculinity such as 'new lad' and 'new dad'. This paper steps aside from the focus on culture and, instead, treats magazine content as a discursive space in which gender and sexuality are oriented to, negotiated, and accomplished within and beyond the magazine itself (i.e. through readers' responses). Specifically, membership categorisation analysis is deployed to explore how the relatively new (and perhaps alternative) category for men - 'metrosexual' - is presented and received. Our analysis suggests that masculinity concerns are central in debates about 'metrosexuality', with self-identified 'metrosexuals' invoking heterosexual prowess and self-respect on the one hand, and critics (e.g. selfidentified 'real men') lamenting 'metrosexuality' for its perceived effeminacy and lack of authenticity on the other. Implications for understanding contemporary masculinities are discussed
On the Spectral Evolution of Cool, Helium-Atmosphere White Dwarfs: Detailed Spectroscopic and Photometric Analysis of DZ Stars
We present a detailed analysis of a large spectroscopic and photometric
sample of DZ white dwarfs based on our latest model atmosphere calculations. We
revise the atmospheric parameters of the trigonometric parallax sample of
Bergeron, Leggett, & Ruiz (12 stars) and analyze 147 new DZ white dwarfs
discovered in the Sloan Digital Sky Survey. The inclusion of metals and
hydrogen in our model atmosphere calculations leads to different atmospheric
parameters than those derived from pure helium models. Calcium abundances are
found in the range from log (Ca/He) = -12 to -8. We also find that fits of the
coolest objects show peculiarities, suggesting that our physical models may not
correctly describe the conditions of high atmospheric pressure encountered in
the coolest DZ stars. We find that the mean mass of the 11 DZ stars with
trigonometric parallaxes, = 0.63 Mo, is significantly lower than that
obtained from pure helium models, = 0.78 Mo, and in much better agreement
with the mean mass of other types of white dwarfs. We determine hydrogen
abundances for 27% of the DZ stars in our sample, while only upper limits are
obtained for objects with low signal-to-noise ratio spectroscopic data. We
confirm with a high level of confidence that the accretion rate of hydrogen is
at least two orders of magnitude smaller than that of metals (and up to five in
some cases) to be compatible with the observations. We find a correlation
between the hydrogen abundance and the effective temperature, suggesting for
the first time empirical evidence of a lower temperature boundary for the
hydrogen screening mechanism. Finally, we speculate on the possibility that the
DZA white dwarfs could be the result of the convective mixing of thin
hydrogen-rich atmospheres with the underlying helium convection zone.Comment: 67 pages, 32 figures, accepted for publication in Ap
Sequence and gene content of a large fragment of a lizard sex chromosome and evaluation of candidate sex differentiating gene R-spondin 1
Background: Scant genomic information from non-avian reptile sex chromosomes is available, and for only a few lizards, several snakes and one turtle species, and it represents only a small fraction of the total sex chromosome sequences in these species. Results: We report a 352 kb of contiguous sequence from the sex chromosome of a squamate reptile, Pogona vitticeps, with a ZZ/ZW sex microchromosome system. This contig contains five protein coding genes (oprd1, rcc1, znf91, znf131, znf180), and major families of repetitive sequences with a high number of copies of LTR and non-LTR retrotransposons, including the CR1 and Bov-B LINEs. The two genes, oprd1 and rcc1 are part of a homologous syntenic block, which is conserved among amniotes. While oprd1 and rcc1 have no known function in sex determination or differentiation in amniotes, this homologous syntenic block in mammals and chicken also contains R-spondin 1 (rspo1), the ovarian differentiating gene in mammals. In order to explore the probability that rspo1 is sex determining in dragon lizards, genomic BAC and cDNA clones were mapped using fluorescence in situ hybridisation. Their location on an autosomal microchromosome pair, not on the ZW sex microchromosomes, eliminates rspo1 as a candidate sex determining gene in P. vitticeps. Conclusion: Our study has characterized the largest contiguous stretch of physically mapped sex chromosome sequence (352 kb) from a ZZ/ZW lizard species. Although this region represents only a small fraction of the sex chromosomes of P. vitticeps, it has revealed several features typically associated with sex chromosomes including the accumulation of large blocks of repetitive sequences
Leukemic blasts program bone marrow adipocytes to generate a protumoral microenvironment
Despite currently available therapies most patients diagnosed with acute myeloid leukemia (AML) die of their disease. Tumor-host interactions are critical for the survival and proliferation of cancer cells; accordingly, we hypothesise that specific targeting of the tumor microenvironment may constitute an alternative or additional strategy to conventional tumor-directed chemotherapy. Since adipocytes have been shown to promote breast and prostate cancer proliferation, and because the bone marrow adipose tissue (MAT) accounts for up to 70% of bone marrow volume in adult humans, we examined the adipocyte-leukaemia cell interactions to determine if they are essential for the growth and survival of AML. Using in-vivo and in-vitro models of AML we show that bone marrow adipocytes from the tumor microenvironment support the survival and proliferation of malignant cells from patients with AML. We show that AML blasts alter metabolic processes in adipocytes to induce phosphorylation of hormone-sensitive lipase and consequently activate lipolysis, which then enables the transfer of fatty acids from adipocytes to AML blasts. In addition, we report that fatty acid binding protein-4 (FABP4) mRNA is up-regulated in adipocytes and AML when in co-culture. FABP4 inhibition using FABP4 shRNA knockdown or a small molecule inhibitor prevents AML proliferation on adipocytes. Moreover, knockdown of FABP4 increases survival in Hoxa9/Meis1-driven AML model. Finally, knockdown of carnitine palmitoyltransferase IA (CPT1A) in an AML patient-derived xenograft model improves survival. Here we report the first description of AML programming bone marrow adipocytes to generate a pro-tumoral microenvironment
Roadmaps to Utopia: Tales of the Smart City
Notions of the Smart City are pervasive in urban development discourses. Various frameworks for the development of smart cities, often conceptualized as roadmaps, make a number of implicit claims about how smart city projects proceed but the legitimacy of those claims is unclear. This paper begins to address this gap in knowledge. We explore the development of a smart transport application, MotionMap, in the context of a £16M smart city programme taking place in Milton Keynes, UK. We examine how the idealized smart city narrative was locally inflected, and discuss the differences between the narrative and the processes and outcomes observed in Milton Keynes. The research shows that the vision of data-driven efficiency outlined in the roadmaps is not universally compelling, and that different approaches to the sensing and optimization of urban flows have potential for empowering or disempowering different actors. Roadmaps tend to emphasize the importance of delivering quick practical results. However, the benefits observed in Milton Keynes did not come from quick technical fixes but from a smart city narrative that reinforced existing city branding, mobilizing a growing network of actors towards the development of a smart region. Further research is needed to investigate this and other smart city developments, the significance of different smart city narratives, and how power relationships are reinforced and constructed through them
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