Deep Appearance Maps

We propose a deep representation of appearance, i. e. the relation of color, surface orientation, viewer position, material and illumination. Previous approaches have used deep learning to extract classic appearance representations relating to reflectance model parameters (e. g. Phong) or illumination (e. g. HDR environment maps). We suggest to directly represent appearance itself as a network we call a deep appearance map (DAM). This is a 4D generalization over 2D reflectance maps, which held the view direction fixed. First, we show how a DAM can be learned from images or video frames and later be used to synthesize appearance, given new surface orientations and viewer positions. Second, we demonstrate how another network can be used to map from an image or video frames to a DAM network to reproduce this appearance, without using a lengthy optimization such as stochastic gradient descent (learning-to-learn). Finally, we generalize this to an appearance estimation-and-segmentation task, where we map from an image showing multiple materials to multiple networks reproducing their appearance, as well as per-pixel segmentation

A36 The TP53 mutations in the Russian patients with de novo DLBCL

BackgroundTP53 dysfunction is implicated in lymphomagenesis and disease progression. Information about the frequency and spectrum of TP53 mutations in the Russian pathients with diffuse large B-cell lymphoma (DLBCL) in the current version of the IARC TP53 Mutation Database R17 is not represented. The goal of this work was to study the frequency, spectrum and functional significance of TP53 mutations in Russian patients with DLBCL.Material and methodsAt the present time the pilot group of 14 patients were included in the study. Diagnosis was assessed according to the criteria of the WHO classification system. Genomic DNA was isolated from formalin-fixed, paraffin embedded tissue blocks. Direct sequence analysis of gene TP53 was performed according to the IARC protocol, 2010 update.ResultsIn two patients were identified single nucleotide substitutions that are not described in the current version of the PubMed database. All of mutations occurred in the DNA-binding domain of p53. The nonsense mutation Arg196Ter was detected in one patient. Previously it was shown that formation of this premature stop codon might activate the nonsense-mediated RNA decay pathway. The second patient had two missense mutations – Leu130Phe and Arg156Cys. The first of them leads to p53 inactivation according to the analysis of the functional importance of amino acid substitutions using service PolyPhen-2.ConclusionWe detected TP53 mutation in 14% cases. The mutational rate in our study is in good agreement with other studies where the frequency of the TP53 mutations in patients with DLBCL ranged mostly from 13% to 23%

Deep Appearance Maps

We propose a deep representation of appearance, i.e. the relation of color, surface orientation, viewer position, material and illumination. Previous approaches have used deep learning to extract classic appearance representations relating to reflectance model parameters (e.g. Phong) or illumination (e.g. HDR environment maps). We suggest to directly represent appearance itself as a network we call a deep appearance map (DAM). This is a 4D generalization over 2D reflectance maps, which held the view direction fixed. First, we show how a DAM can be learned from images or video frames and later be used to synthesize appearance, given new surface orientations and viewer positions. Second, we demonstrate how another network can be used to map from an image or video frames to a DAM network to reproduce this appearance, without using a lengthy optimization such as stochastic gradient descent (learning-to-learn). Finally, we show the example of an appearance estimation-and-segmentation task, mapping from an image showing multiple materials to multiple deep appearance maps

Forest decline caused by high soil water conditions in a permafrost region

In the permafrost region near Yakutsk, eastern Siberia, Russia, annual precipitation (June–May) in 2005–2006 and 2006–2007 exceeded the 26-year (1982–2008) mean of 222±68 mm by 185 mm and 128 mm, respectively, whereas in 2007–2008 the excedent was only 48 mm, well within the range of variability. Yellowing and browning of larch (<I>Larix cajanderi</I> Mayr.) trees occurred in an undisturbed forest near Yakutsk in the 2007 summer growing season. Soil water content at a depth of 0.20 m was measured along a roughly 400 m long line transect running through areas of yellowing and browning larch trees (YBL) and of normal larch trees (NL). In the two years of supranormal precipitation, soil water content was very high compared to values recorded for the same area in previous studies. For both wet years, the mean degree of saturation (<I>s</I>) was significantly greater in YBL than NL areas, whereas the converse was the case for the gas diffusivity in soil. This implies that rather than mitigating water stress suffered during normal precipitation years, elevated soil water conditions adversely affected the growth of larch trees. Eastern Siberia's taiga forest extends widely into the permafrost region. Was such supranormal annual precipitation to extend for more than two years, as might be expected under impending global climate changes, forest recovery may not be expected and emission of greenhouse gas might continue in future

Monitoring synaptic transmission in primary neuronal cultures using local extracellular stimulation

Various techniques have been applied for the functional analysis of synaptic transmission in Cultured neurons. Here, we describe a method of studying synaptic transmission in neurons cultured at high-density from different brain regions such as the cortex, striatum and spinal cord. We use postsynaptic whole-cell recordings to monitor synaptic Currents triggered by presynaptic action potentials that are induced by brief stimulations with a nearby extracellular bipolar electrode. Pharmacologically isolated excitatory or inhibitory postsynaptic currents can be reliably induced, with amplitudes, synaptic charge transfers, and short-term plasticity properties that are reproducible from culture to culture. We show that the size and kinetics of pharmacologically isolated inhibitory postsynaptic Currents triggered by single action potentials or stimulus trains depend on the Ca2+ concentration, temperature and stimulation frequency. This method can be applied to study synaptic transmission in wildtype neurons infected with lentiviruses encoding various components of presynaptic release machinery, or in neurons from genetically modified mice, for example neurons carrying floxed genes in which gene expression can be acutely ablated by expression of Cre recombinase. The preparation described in this paper should be useful for analysis of synaptic transmission in inter-neuronal synapses formed by different types of neurons. (c) 2006 Elsevier B.V. All rights reserved

The carbon budget of a tundra in the north-eastern Russian Arctic during the snow free season and its stability in the 2003-2016 period

Large quantities of carbon are stored in the terrestrial permafrost of the Arctic region where the rate of climate warming is two to three times more than the global mean and the largest temperature anomalies observed in autumn and winter. The quantification of the impact of climate warming on the degradation of permafrost and the associated potential release to the atmosphere of carbon stocked in the soil in the form of greenhouse gases, thus further increasing the radiative forcing of the atmosphere, is a research priority in the field of biogeosciences. Land-atmosphere turbulent fluxes of CO2 and CH4 have been monitored at the tundra site of Kytalyk in north-eastern Siberia (70,82 N; 147.48 E) by means of eddy covariance since 2003 and 2008, respectively; regular measurement campaigns have been carried out since then. Here we present results of the seasonal CO2 budget of the tundra ecosystem for the 2003-2016 period based on observations encompassing the permafrost thawing season and analyze the inter-annual differences in the seasonal patterns of CO2 fluxes considering the separate the contribution of climatic drivers and ecosystem functional parameters relative to the processes of respiration and photosynthesis. The variability of the CO2 budget is also discussed in view of the impact of the timing and length of the snow free period. The Kytalyk tundra acted as an atmospheric carbon dioxide sink with relatively small inter-annual variability (-96.1±11.9 gC m-2) during the snow free season and the seasonal CO2 budget did not show any trend over time. The pronounced meteorological variability characterizing Arctic summers was a key factor in shaping the length of the carbon uptake period, which did not progressively increased despite its tendency to start earlier, and in determining the magnitude of CO2 fluxes. No clear evidence of inter-annual changes in the eco-physiological response parameters of CO2 fluxes to climatic drivers (global radiation and air temperature) was found along the course of the analysed period. Methane fluxes had a minor contribution to the carbon budget of the snow-free season representing on average an emission of 3.2 gC m-2 (2008-2016) with apparently small inter-annual variability. Similarly, the size of the carbon exported laterally from the ecosystem in the form of dissolved organic carbon flux amounted to 3.1 gC m-2 as determined experimentally. After including these last terms in the budget, the magnitude of the carbon sink associated with the net ecosystem productivity is reduced by 6%, while the GHG budget still denotes a sink of -60.4 ± 11.9 gC-CO2eq (methane GWP over 100-year time horizon). The monitored tundra was to date exerting a steady climate warming mitigation effect as far as the snow free season is concerned, however the figure of its carbon sink could be potentially sensibly lower due to overlooked emissions in the autumn freeze-up and early winter periods. Also, nonlinear accelerations in the permafrost degradation could happen once tipping points in the Arctic climate are exceeded. Both aspects underline the relevance of long term and continuous biogeochemical monitoring in permafrost tundra environments

Off-diagonal quark distribution functions of the pion within an effective single instanton approximation

We develop a relativistic quark model for pion structure, which incorporates the non-trivial structure of the vacuum of Quantum Chromodynamics as modelled by instantons. Pions are boundstates of quarks and the strong quark-pion vertex is determined from an instanton induced effective lagrangian. The interaction of the constituents of the pion with the external electromagnetic field is introduced in gauge invariant form. The parameters of the model, i.e., effective instanton radius and constituent quark masses, are obtained from the vacuum expectation values of the lowest dimensional quark and gluon operators and the low-energy observables of the pion. We apply the formalism to the calculation of the pion form factor by means of the isovector nonforward parton distributions and find agreement with the experimental data.Comment: LaTeX; altered version; references and figures added. Published: paper has been accepted for publication in Nucl. Phys.

Future biogeochemical forcing in Eastern Siberia: cooling or warming?

Over-proportional warming in the northern high latitudes, and large carbon stocks in boreal and (sub)arctic ecosystems have raised concerns as to whether substantial positive climate feedbacks from biogeochemical process responses should be expected. Such feedbacks occur if increasing temperatures lead to e.g., a net release of CO2 or CH4. However, temperature-enhanced emissions of biogenic volatile organic compounds (BVOC) have been shown to contribute to a cooling feedback via growth of secondary organic aerosol (SOA), and related aerosol forcings. Combining measurements in Eastern Siberia with model-based estimates of vegetation and permafrost dynamics, BVOC emissions and aerosol growth, we show here that the additional climate forcing from changes in ecosystem CO2 balance and BVOC-SOA interactions nearly cancel on a regional scale. The interactions between emissions and vegetation dynamics that underlie individual forcing estimates are complex and highlight the importance of addressing ecosystem-climate feedbacks in consistent, process-based model frameworks that account for a multitude of system processes

Critical Strain Region Evaluation of Self-Assembled Semiconductor Quantum Dots

A novel peak finding method to map the strain from high resolution transmission electron micrographs, known as the Peak Pairs method, has been applied to In(Ga) As/AlGaAs quantum dot (QD) samples, which present stacking faults emerging from the QD edges. Moreover, strain distribution has been simulated by the finite element method applying the elastic theory on a 3D QD model. The agreement existing between determined and simulated strain values reveals that these techniques are consistent enough to qualitatively characterize the strain distribution of nanostructured materials. The correct application of both methods allows the localization of critical strain zones in semiconductor QDs, predicting the nucleation of defects, and being a very useful tool for the design of semiconductor device