Incremental learning of abnormalities in autonomous systems

In autonomous systems, self-awareness capabilities are useful to allow artificial agents to detect abnormal situations based on previous experiences. This paper presents a method that facilitates the incremental learning of new models by an agent. Available learned models can dynamically generate probabilistic predictions as well as evaluate their mismatch from current observations. Observed mismatches are grouped through an unsupervised learning strategy into different classes, each of them corresponding to a dynamic model in a given region of the state space. Such clusters define switching Dynamic Bayesian Networks (DBNs) employed for predicting future instances and detect anomalies. Inferences generated by several DBNs that use different sensorial data are compared quantitatively. For testing the proposed approach, it is considered the multi-sensorial data generated by a robot performing various tasks in a controlled environment and a real autonomous vehicle moving at a University Campus

Abnormality detection using graph matching for multi-task dynamics of autonomous systems

Self-learning abilities in autonomous systems are essential to improve their situational awareness and detection of normal/abnormal situations. In this work, we propose a graph matching technique for activity detection in autonomous agents by using the Gromov-Wasserstein framework. A clustering approach is used to discretise continuous agents' states related to a specific task into a set of nodes with similar objectives. Additionally, a probabilistic transition matrix between nodes is used as edges weights to build a graph. In this paper, we extract an abnormal area based on a sub-graph that encodes the differences between coupled of activities. Such sub-graph is obtained by applying a threshold on the optimal transport matrix, which is obtained through the graph matching procedure. The obtained results are evaluated through experiments performed by a robot in a simulated environment and by a real autonomous vehicle moving within a University Campus

Isomalto/malto-polysaccharides from starch : Reaction pathways and new characterization strategies

The 4,6-α-glucanotransferase (GTFB) enzyme is able to convert starch into isomalto/malto-polysaccharides (IMMPs). Although the proof of principle has been demonstrated that IMMPs can be produced from several starches, the influence of the structural properties of the starch substrate and the role of additionally present sugars during IMMP synthesis has remained unknown. Until now, since this has been the core topic of the research presented in this thesis. In chapter 2 we analyse the influence of the structural properties of starch-based substrates on the final IMMP structure. In chapter 3 we present and demonstrate an enzymatic fingerprinting method specially developed for the analysis of isomalto/malto-polysaccharides. In chapter 4 we investigate the reaction dynamics of the GTFB enzyme by following GTFB modification on two linear substrates with varying chain length distributions. In chapter 5 we demonstrate how the presence of mono- and di-saccharides change the outcome of GTFB modification and demonstrate that we are able to direct the modification of IMMPs. In chapter 6 we discuss potential applications and the future perspectives of isomalto/malto-polysaccharides and the GTFB enzyme.</p

Overexpression of a novel Arabidopsis gene related to putative zinc-transporter genes from animals can lead to enhanced zinc resistance and accumulation.

Microbial Biotechnolog

Comparison of Transforming Growth Factor 1 (TGF-β1) Expression in Various Lysate Platelet-Rich Fibrin (L-PRF) Concentrations on Human Dental Pulp Stem Cell Differentiation

Objective: To compare Transforming growth factor-β1 (TGF-β1) expression in various L-PRF concentrations on the hDPSC differentiation process. Material and Methods: hDPSC cell cultures were subjected to serum starvation by reducing FBS levels in the hDPSC culture media. Lysate PRF was obtained from the PRF gel, which was then incubated at 4°C for 24 h. The supernatant was dried, transferred to a 2-ml Eppendorf tube, and stored at −20°C. The evaluation of TGF-β1 expression in 1%, 5%, 10%, and 25% L-PRF samples and 10% FBS (control) during the process of hDPSC differentiation was quantified using an ELISA reader on day 7. The expression of TGF-β1 was subjected to a one-way ANOVA test, followed by Bonferroni’s post hoc test with significant values (p&lt;0.05). Results: Significant differences were noted in TGF-β1 expression between 1%, 5%, 10%, and 25% L-PRF and the control group (10% FBS). The highest TGF-β1 expression occurred with 25% L-PRF (0.645 ± 0.048), followed by 10% L-PRF (0.461 ± 0.035), 10% FBS (0.374 ± 0.013), 5% L-PRF (0.275 ± 0.045), and the lowest expression was with 1% L-PRF (0.160 ± 0.045). Conclusion: The best result of TGF-B1 expression in hDPSC differentiation was in the 25% L-PRF group

High-precision calculations of In I and Sn II atomic properties

We use all-order relativistic many-body perturbation theory to study 5s^2 nl configurations of In I and Sn II. Energies, E1-amplitudes, and hyperfine constants are calculated using all-order method, which accounts for single and double excitations of the Dirac-Fock wave functions.Comment: 10 pages, accepted to PRA; v2: Introduction changed, references adde

Golgi Membranes Are Absorbed into and Reemerge from the ER during Mitosis

AbstractQuantitative imaging and photobleaching were used to measure ER/Golgi recycling of GFP-tagged Golgi proteins in interphase cells and to monitor the dissolution and reformation of the Golgi during mitosis. In interphase, recycling occurred every 1.5 hr, and blocking ER egress trapped cycling Golgi enzymes in the ER with loss of Golgi structure. In mitosis, when ER export stops, Golgi proteins redistributed into the ER as shown by quantitative imaging in vivo and immuno-EM. Comparison of the mobilities of Golgi proteins and lipids ruled out the persistence of a separate mitotic Golgi vesicle population and supported the idea that all Golgi components are absorbed into the ER. Moreover, reassembly of the Golgi complex after mitosis failed to occur when ER export was blocked. These results demonstrate that in mitosis the Golgi disperses and reforms through the intermediary of the ER, exploiting constitutive recycling pathways. They thus define a novel paradigm for Golgi genesis and inheritance

A Multiphase Suzaku Study Of X-Rays From Tau Sco

We obtained relatively high signal-to-noise X-ray spectral data of the early massive star tau Sco (B0.2V) with the Suzaku X-ray Imaging Spectrometer (XIS) instrument. This source displays several unusual features that motivated our study: (1) redshifted absorption in UV P Cygni lines to approximately +250 km s(-1) suggestive of infalling gas, (2) unusually hard X-ray emission requiring hot plasma at temperatures in excess of 10 MK whereas most massive stars show relatively soft X-rays at a few MK, and (3) a complex photospheric magnetic field of open and closed field lines. In an attempt to understand the hard component better, X-ray data were obtained at six roughly equally spaced phases within the same epoch of tau Sco\u27s 41 day rotation period. The XIS instrument has three operable detectors: XIS1 is back-illuminated with sensitivity down to 0.2 keV; XIS0 and XIS2 are front-illuminated with sensitivity only down to 0.4 keV and have an overall less effective area than XIS1. The XIS0 and XIS3 detectors show relatively little variability. In contrast, there is a approximate to 4 sigma detection of a approximate to 4% drop in the count rate of the XIS1 detector at one rotational phase. In addition, all three detectors show a approximate to 3% increase in count rate at the same phase. The most optimistic prediction of X-ray variability allows for a 40% change in the count rate, particularly near phases where we have pointings. Observed modulations in the X-ray light curve on the rotation cycle is an order of magnitude smaller than this, which places new stringent constraints on future modeling of this interesting magnetic massive star

Grasping trapezoidal objects

When grasping rectangular or circular objects with a precision grip the digits close in on the object in opposite directions. In doing so the digits move perpendicular to the local surface orientation as they approach opposite sides of the object. This perpendicular approach is advantageous for accurately placing the digits. Trapezoidal objects have non-parallel surfaces so that moving the digits in opposite directions would make the digits approach the contact surfaces at an angle that is not 90°. In this study we examined whether this happens, or whether subjects tend to approach trapezoidal objects’ surfaces perpendicularly. We used objects of different sizes and with different surface slants. Subjects tended to approach the object’s surfaces orthogonally, suggesting that they aim for an optimal precision of digit placement rather than simply closing their hand as it reaches the object