Towards semi-supervised learning of semantic spatial concepts for mobile robots

The ability of building robust semantic space representations of environments is crucial for the development of truly autonomous robots. This task, inherently connected with cognition, is traditionally achieved by training the robot with a supervised learning phase. We argue that the design of robust and autonomous systems would greatly benefit from adopting a semi-supervised online learning approach. Indeed, the support of open-ended, lifelong learning is fundamental in order to cope with the dazzling variability of the real world, and online learning provides precisely this kind of ability. Here we focus on the robot place recognition problem, and we present an online place classification algorithm that is able to detect gap in its own knowledge based on a confidence measure. For every incoming new image frame, the method is able to decide if (a) it is a known room with a familiar appearance, (b) it is a known room with a challenging appearance, or (c) it is a new, unknown room. Experiments on ImageCLEF database and a subset of the challenging COLD database show the promise of our approach

Additional file 1: of Retention of hexanucleotide repeat-containing intron in C9orf72 mRNA: implications for the pathogenesis of ALS/FTD

Supplementary material. (PDF 456 kb

Allele-specific siRNA silences the mutant allele specifically and reduces cytoplasmic inclusions in HEK293 cells.

<p><b>A.</b> HA-TDP-43^wt stably expressing HEK293 cells were co-transfected with C-terminal GFP-TDP-43^wt or GFP-TDP-43^M337V and siRNAs for 48 hours. Cells were fixed and stained with HA antibody (red) and DAPI (blue). GFP-TDP-43 cytosolic and nuclear inclusions of different sizes were seen. C-terminal GFP-TDP-43^wt and GFP-TDP43^M337V inclusions co-localized with full length HA-TDP-43^wt (arrows), however some inclusions did not recruit full length HA-TDP-43^wt (arrowhead). Scale bars = 20 µm. <b>B.</b> Percentage of cells with GFP aggregates. siM9 reduced the number of cells with aggregates in GFP-TDP-43^M337V – expressing cells. More than 70 000 cells were counted from three independent experiments. Error bars represent SEM (Student's T-test,*** P<0.001).</p

Allele-specific siRNAs targeting TDP-43^M337V mutant allele.

<p><b>A.</b> Schematic representation of TDP-43 protein containing two RNA-recognition motifs (RRM1 and RRM2), a bipartite nuclear localization signal (NLS), a nuclear export signal (NES) and a glycine-rich domain in the carboxy-terminal. The M337V mutation localization is indicated. Five allele-specific siRNAs were designed to contain mismatches at positions 9 (M9), 3 (M3), or 17 (M17); double mismatches at positions 8 and 9 (M8-9) or multiple mismatches at positions 5, 7, 10 and 16 (M5U). <b>B.</b> Representative western blot image showing the effects of allele-specific siRNA on cells transfected with GFP-TDP-43^wt and GFP-TDP-43^M337V. The allele-specific siM9 reduces the levels of GFP-TDP-43^M337V specifically whereas GFP-TDP-43^wt levels remain unchanged. FLAG-tagged protein was used as a control for transfection efficiency. <b>C.</b> Densitometry analysis of relative GFP-TDP-43 normalised to GAPDH. Mean from three independent experiments. Error bars represent standard error of the mean (SEM). (One way ANOVA, * P<0.05; *** P<0.001).</p

Allele-specific siM9 decreases total TDP-43 transcripts and protein levels in neuralised cells.

<p><b>A.</b> Representative Western blot image showing M337V knockdown in M337V lines. <b>B.</b> Densitometry analysis of relative TDP-43 protein normalised to GAPDH. <b>C.</b> qPCR display unchanged levels of total TDP-43 in the control lines transfected with siM9, whereas M337V lines showed a reduction. Error bars represent SEM (One way ANOVA, * P<0.05, ** P<0.01, *** P<0.001).</p

Allele-specific knockdown of M337V allele on neural stem cells.

<p><b>A.</b> NSCs were transfected with allele-specific siM9 and stained for TDP-43. Images were acquired using identical parameters and analysed using Metamorph software. Representative confocal immunolabeling images showing allele-specific M337V knockdown in M337V lines. The allele-specific siM9 reduces endogenous TDP-43^M337V expression in all compartments (cytosolic (<b>B</b>), nuclear (<b>C</b>) and total (<b>D</b>) TDP-43) (n = 3 independent experiments. ** P<0.01 and *** P<0.001).</p