1,546 research outputs found
Group-level Emotion Recognition using Transfer Learning from Face Identification
In this paper, we describe our algorithmic approach, which was used for
submissions in the fifth Emotion Recognition in the Wild (EmotiW 2017)
group-level emotion recognition sub-challenge. We extracted feature vectors of
detected faces using the Convolutional Neural Network trained for face
identification task, rather than traditional pre-training on emotion
recognition problems. In the final pipeline an ensemble of Random Forest
classifiers was learned to predict emotion score using available training set.
In case when the faces have not been detected, one member of our ensemble
extracts features from the whole image. During our experimental study, the
proposed approach showed the lowest error rate when compared to other explored
techniques. In particular, we achieved 75.4% accuracy on the validation data,
which is 20% higher than the handcrafted feature-based baseline. The source
code using Keras framework is publicly available.Comment: 5 pages, 3 figures, accepted for publication at ICMI17 (EmotiW Grand
Challenge
Salicylic Acid, an Ambimobile Molecule Exhibiting a High Ability to Accumulate in the Phloem
International audienceThe ability of exogenous salicylic acid (SA) to accumulate in castor bean (Ricinus communis) phloem was evaluated by HPLC and liquid scintillation spectrometry analyses of phloem sap collected from the severed apical part of seedlings. Time-course experiments indicated that SA was transported to the root system via the phloem and redistributed upward in small amounts via the xylem. This helps to explain the peculiarities of SA distribution within the plant in response to biotic stress and exogenous SA application. Phloem loading of SA at 1, 10, or 100 mM was dependent on the pH of the cotyledon incubating solution, and accumulation in the phloem sap was the highest (about 10-fold) at the most acidic pH values tested (pH 4.6 and 5.0). As in animal cells, SA uptake still occurred at pH values close to neutrality (i.e. when SA is only in its dissociated form according to the calculations made by ACD LogD suite software). The analog 3,5-dichlorosalicylic acid, which is predicted to be nonmobile according to the models of Bromilow and Kleier, also moved in the sieve tubes. These discrepancies and other data may give rise to the hypothesis of a possible involvement of a pH-dependent carrier system translocating aromatic monocarboxylic acids in addition to the ion-trap mechanism
C/C ratio in planetary nebulae from the IUE archives
We investigated the abundance ratio of C/C in planetary nebulae
by examining emission lines arising from \ion{C}{3} 2s2p ^3P_{2,1,0} \to 2s^2
^1S_0. Spectra were retrieved from the International Ultraviolet Explorer
archives, and multiple spectra of the same object were coadded to achieve
improved signal-to-noise. The C hyperfine structure line at 1909.6 \AA
was detected in NGC 2440. The C/C ratio was found to be
1.2. In all other objects, we provide an upper limit for the flux
of the 1910 \AA line. For 23 of these sources, a lower limit for the
C/C ratio was established. The impact on our current
understanding of stellar evolution is discussed.
The resulting high signal-to-noise \ion{C}{3} spectrum helps constrain the
atomic physics of the line formation process. Some objects have the measured
1907/1909 flux ratio outside the low-electron density theoretical limit for
C. A mixture of C with C helps to close the gap somewhat.
Nevertheless, some observed 1907/1909 flux ratios still appear too high to
conform to the presently predicted limits. It is shown that this limit, as well
as the 1910/1909 flux ratio, are predominantly influenced by using the standard
partitioning among the collision strengths for the multiplet --
according to the statistical weights. A detailed calculation for the fine
structure collision strengths between these individual levels would be
valuable.Comment: ApJ accepted: 19 pages, 3 Figures, 2 Table
Synthesis and Antimalarial Activity of 11 Dispiro-1,2,4,5-tetraoxane Analogues of WR 148999. 7,8,15,16-Tetraoxadispiro[5.2.5.2]hexadecanes Substituted at the 1 and 10 Positions with Unsaturated and Polar Functional Groups
Eleven novel dispiro-1,2,4,5-tetraoxanes 3 bearing unsaturated and polar functional groups were designed to enhance the oral antimalarial activity of the prototype tetraoxane 2 (WR 148999). With the exception of 3g and 3h, tetraoxanes 3 were available via the peroxidation of corresponding cyclohexanone derivatives in H2SO4/CH3CN. Tetraoxanes 3g and 3h were prepared by hydrolysis of ester tetraoxanes 3e and 3i, respectively. Five of the 11 tetraoxanes were inactive, but six tetraoxanes had IC50 values of 6-26 nM against the K1 and NF54 strains of Plasmodium falciparum compared to corresponding IC50 values of 28 and 39 nM for 2, and 10 and 12 nM for artemisinin (1). Ester tetraoxane 3e was the most active in vitro, some 2-fold more potent than 1. However, none of the six tetraoxanes active in vitro were as effective as either 1 or 2 in vivo; at single doses of 100 mg/kg most possessed little to no vivo activity in mice infected with Plasmodium berghei. Unsaturated tetraoxane 3a was uniquely more active when administered per os (po) than subcutan (sc). For this series of tetraoxanes, the discrepancy between vitro and vivo activities underscores the limitations of conclusions drawn solely from in vitro antimalarial data and illustrates a practical benefit of complementary single-dose in vivo antimalarial screens
Using Open Source Libraries in the Development of Control Systems Based on Machine Vision
The possibility of the boundaries detection in the images of crushed ore particles using a convolutional neural network is analyzed. The structure of the neural network is given. The construction of training and test datasets of ore particle images is described. Various modifications of the underlying neural network have been investigated. Experimental results are presented. © 2020, IFIP International Federation for Information Processing.Foundation for Assistance to Small Innovative Enterprises in Science and Technology, FASIEFunding. The work was performed under state contract 3170ΓC1/48564, grant from the FASIE
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