MicroRNA expression in lymphocyte development and malignancy

This article is available open access through the publisher’s website. Copyright @ 2008 Macmillan Publishers Limited.No abstract available.The Leukemia Research Fund, the Julian Starmer-Smith Memorial Fund, and the Medical Research Council

Concept of an Effective Sentinel-1 Satellite SAR Interferometry System

This brief study introduces a partially working concept being developed at IT4Innovations supercomputer (HPC) facility. This concept consists of several modules that form a whole body of an efficient system for observation of terrain or objects displacements using satellite SAR interferometry (InSAR). A metadata database helps to locate data stored in various storages and to perform basic analyzes. A special database has been designed to describe Sentinel-1 data, on its burst level. Custom Sentinel-1 TOPS processing algorithms allow an injection of coregistered bursts into the database. Once the area of interest is set and basic processing parameters are given, the selected data are merged and processed by the Persistent Scatterers (PS) InSAR method or an optimized Small Baselines (SB) InSAR derivative. Depending on the expected deliverables, the processing results can be post-analyzed using a custom approach, in order to achieve a set of reliable measurement points. Final results can be post-processed and visualized using a custom GIS toolbox, consisting in open-source GIS functionality. The GIS post-processing is enforced by HPC power as well. To demonstrate the practical applicability of the described system, a subsidence area in Konya city, Turkey is used as the study area for Sentinel-1 InSAR evaluation

Large introns in relation to alternative splicing and gene evolution: a case study of Drosophila bruno-3

Background: Alternative splicing (AS) of maturing mRNA can generate structurally and functionally distinct transcripts from the same gene. Recent bioinformatic analyses of available genome databases inferred a positive correlation between intron length and AS. To study the interplay between intron length and AS empirically and in more detail, we analyzed the diversity of alternatively spliced transcripts (ASTs) in the Drosophila RNA-binding Bruno-3 (Bru-3) gene. This gene was known to encode thirteen exons separated by introns of diverse sizes, ranging from 71 to 41,973 nucleotides in D. melanogaster. Although Bru-3's structure is expected to be conducive to AS, only two ASTs of this gene were previously described. Results: Cloning of RT-PCR products of the entire ORF from four species representing three diverged Drosophila lineages provided an evolutionary perspective, high sensitivity, and long-range contiguity of splice choices currently unattainable by high-throughput methods. Consequently, we identified three new exons, a new exon fragment and thirty-three previously unknown ASTs of Bru-3. All exon-skipping events in the gene were mapped to the exons surrounded by introns of at least 800 nucleotides, whereas exons split by introns of less than 250 nucleotides were always spliced contiguously in mRNA. Cases of exon loss and creation during Bru-3 evolution in Drosophila were also localized within large introns. Notably, we identified a true de novo exon gain: exon 8 was created along the lineage of the obscura group from intronic sequence between cryptic splice sites conserved among all Drosophila species surveyed. Exon 8 was included in mature mRNA by the species representing all the major branches of the obscura group. To our knowledge, the origin of exon 8 is the first documented case of exonization of intronic sequence outside vertebrates. Conclusion: We found that large introns can promote AS via exon-skipping and exon turnover during evolution likely due to frequent errors in their removal from maturing mRNA. Large introns could be a reservoir of genetic diversity, because they have a greater number of mutable sites than short introns. Taken together, gene structure can constrain and/or promote gene evolution

Global Monitoring of Fault Zones and Volcanoes with Sentinel-1

Sentinel-1 represents a major step forward in enabling us to monitor the Earth's hazardous tectonic and volcanic zones. Here, we present the latest progress from the Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics (COMET), where we provide deformation results to the community for volcanoes and the tectonic belts. For the estimation of seismic hazard, we require relative accuracy on the order of 1 mm/yr between points 100 km apart. This requires mass processing of long time series of radar acquisitions. As of January 2018, we are producing in-terferograms systematically for the entire Alpine-Himalayan belt (~9000 × 2000 km) and the majority of subaerial volcanoes. Currently we make interferograms and coherence products available to the community, but we plan to also provide average deformation rates and displacement time series, in the future. The results are made available through a dedicated COMET portal, and we are in the process of linking them to the ESA G-TEP and EPOS. COMET also responds routinely to significant continental earthquakes, larger than ~Mw 6.0. The short repeat interval of Sentinel-1, together with the rapid availability of the data, allows us to do this within a few days for most earthquakes. For example, after the Mw 7.8 Kaikoura earthquake we supplied a processed interferogram to the community just 5 hours and 37 minutes after the Sentinel-1 acquisition. In this paper we provide an overview of some of the latest results for tectonics and volcanism and discuss how the accuracy of these products will improve as the number of data products acquired by Sentinel-1 increases

Economic-demographic interactions in long-run growth

Cliometrics confirms that Malthus’ model of the pre-industrial economy, in which increases in productivity raise population but higher population drives down wages, is a good description for much of demographic/economic history. A contributor to the Malthusian equilibrium was the Western European Marriage Pattern, the late age of female first marriage, which promised to retard the fall of living standards by restricting fertility. The demographic transition and the transition from Malthusian economies to modern economic growth attracted many Cliometric models surveyed here. A popular model component is that lower levels of mortality over many centuries increased the returns to, or preference for, human capital investment so that technical progress eventually accelerated. This initially boosted birth rates and population growth accelerated. Fertility decline was earliest and most striking in late eighteenth century France. By the 1830s the fall in French marital fertility is consistent with a response to the rising opportunity cost of children. The rest of Europe did not begin to follow until end of the nineteenth century. Interactions between the economy and migration have been modelled with Cliometric structures closely related to those of natural increase and the economy. Wages were driven up by emigration from Europe and reduced in the economies receiving immigrants

Crack formation and prevention in colloidal drops

Crack formation is a frequent result of residual stress release from colloidal films made by the evaporation of colloidal droplets containing nanoparticles. Crack prevention is a significant task in industrial applications such as painting and inkjet printing with colloidal nanoparticles. Here, we illustrate how colloidal drops evaporate and how crack generation is dependent on the particle size and initial volume fraction, through direct visualization of the individual colloids with confocal laser microscopy. To prevent crack formation, we suggest use of a versatile method to control the colloid-polymer interactions by mixing a nonadsorbing polymer with the colloidal suspension, which is known to drive gelation of the particles with short-range attraction. Gelation-driven crack prevention is a feasible and simple method to obtain crack-free, uniform coatings through drying-mediated assembly of colloidal nanoparticlesopen0

Children’s Internal Attributions of Anxiety-Related Physical Symptoms: Age-Related Patterns and the Role of Cognitive Development and Anxiety Sensitivity

The present study examined age-related patterns in children’s anxiety-related interpretations and internal attributions of physical symptoms. A large sample of 388 children aged between 4 and 13 years completed a vignette paradigm during which they had to explain the emotional response of the main character who experienced anxiety-related physical symptoms in a variety of daily situations. In addition, children completed measures of cognitive development and anxiety sensitivity. Results demonstrated that age, cognitive development, and anxiety sensitivity were all positively related to children’s ability to perceive physical symptoms as a signal of anxiety and making internal attributions. Further, while a substantial proportion of the younger children (i.e., <7 years) were able to make a valid anxiety-related interpretation of a physical symptom, very few were capable of making an internal attribution, which means that children of this age lack the developmental prerequisites for applying physical symptoms-based theories of childhood anxiety

Effects of Simulated Microgravity on Embryonic Stem Cells

There have been many studies on the biological effects of simulated microgravity (SMG) on differentiated cells or adult stem cells. However, there has been no systematic study on the effects of SMG on embryonic stem (ES) cells. In this study, we investigated various effects (including cell proliferation, cell cycle distribution, cell differentiation, cell adhesion, apoptosis, genomic integrity and DNA damage repair) of SMG on mouse embryonic stem (mES) cells. Mouse ES cells cultured under SMG condition had a significantly reduced total cell number compared with cells cultured under 1 g gravity (1G) condition. However, there was no significant difference in cell cycle distribution between SMG and 1G culture conditions, indicating that cell proliferation was not impaired significantly by SMG and was not a major factor contributing to the total cell number reduction. In contrast, a lower adhesion rate cultured under SMG condition contributed to the lower cell number in SMG. Our results also revealed that SMG alone could not induce DNA damage in mES cells while it could affect the repair of radiation-induced DNA lesions of mES cells. Taken together, mES cells were sensitive to SMG and the major alterations in cellular events were cell number expansion, adhesion rate decrease, increased apoptosis and delayed DNA repair progression, which are distinct from the responses of other types of cells to SMG

The Effects of NMDA Subunit Composition on Calcium Influx and Spike Timing-Dependent Plasticity in Striatal Medium Spiny Neurons

Calcium through NMDA receptors (NMDARs) is necessary for the long-term potentiation (LTP) of synaptic strength; however, NMDARs differ in several properties that can influence the amount of calcium influx into the spine. These properties, such as sensitivity to magnesium block and conductance decay kinetics, change the receptor's response to spike timing dependent plasticity (STDP) protocols, and thereby shape synaptic integration and information processing. This study investigates the role of GluN2 subunit differences on spine calcium concentration during several STDP protocols in a model of a striatal medium spiny projection neuron (MSPN). The multi-compartment, multi-channel model exhibits firing frequency, spike width, and latency to first spike similar to current clamp data from mouse dorsal striatum MSPN. We find that NMDAR-mediated calcium is dependent on GluN2 subunit type, action potential timing, duration of somatic depolarization, and number of action potentials. Furthermore, the model demonstrates that in MSPNs, GluN2A and GluN2B control which STDP intervals allow for substantial calcium elevation in spines. The model predicts that blocking GluN2B subunits would modulate the range of intervals that cause long term potentiation. We confirmed this prediction experimentally, demonstrating that blocking GluN2B in the striatum, narrows the range of STDP intervals that cause long term potentiation. This ability of the GluN2 subunit to modulate the shape of the STDP curve could underlie the role that GluN2 subunits play in learning and development

Doll Play narratives about starting school in children of socially anxious mothers, and their relation to subsequent child school-based anxiety

Background: Child social anxiety is common, and predicts later emotional and academic impairment. Offspring of socially anxious mothers are at increased risk. It is important to establish whether individual vulnerability to disorder can be identified in young children. Method: The responses of 4.5 year-old children of mothers with social phobia (N = 62) and non-anxious mothers (N = 60) were compared, two months before school entry, using a Doll Play (DP) procedure focused on the social challenge of starting school. DP responses were examined in relation to teacher reports of anxious-depressed symptoms and social worries at the end of the child’s first school term. The role of earlier child behavioral inhibition and attachment, assessed at 14 months, was also considered. Results: Compared to children of non-anxious mothers, children of mothers with social phobia were significantly more likely to give anxiously negative responses in their school DP (OR = 2.57). In turn, negative DP predicted teacher reported anxious-depressed and social worry problems. There were no effects of infant behavioral inhibition or attachment. Conclusion: Vulnerability in young children at risk of anxiety can be identified using Doll Play narratives