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In the development of human–machine interfaces, facial expression analysis has attracted considerable attention, as it provides a natural and efficient way of communication. Congruence between facial and behavioral inference in face processing is considered a serious challenge that needs to be solved in the near future. Automatic facial expression is a difficult classification issue because of the high interclass variability caused by the significant interdependence of the environmental conditions on the face appearance caused by head pose, scale, and illumination occlusions from their variances. In this paper, an adaptive model for smile classification is suggested that integrates a row-transform-based feature extraction algorithm and a cascade classifier to increase the precision of facial recognition. We suggest a histogram-based cascade smile classification method utilizing different facial features. The candidate feature set was designed based on the first-order histogram probability, and a cascade classifier with a variety of parameters was used at the classification stage. Row transformation is used to exclude any unnecessary coefficients in a vector, thereby enhancing the discriminatory capacity of the extracted features and reducing the sophistication of the calculations. Cascading gives the opportunity to train an extremely precise classification by taking a weighted average of poor learners’ decisions. Through accumulating positive and negative images of a single object, this algorithm can build a complete classifier capable of classifying different smiles in a limited amount of time (near real time) and with a high level of precision (92.2–98.8%) as opposed to other algorithms by large margins (5% compared with traditional neural network and 2% compared with Deep Neural Network based methods).

The amphipod crustacean Parhyale hawaiensis has been put forward as an attractive organism for evolutionary developmental comparisons, and considerable effort is being invested in isolating developmental genes and studying their expression patterns in this species. The scope of these studies could be significantly expanded by establishing means for genetic manipulation that would enable direct studies of gene functions to be carried out in this species. Here, we report the use of the Minos transposable element for the genetic transformation of P. hawaiensis. Transformed amphipods can be obtained from ≈30% of surviving individuals injected with both a Minos element carrying the 3xP3-DsRed fluorescent marker and with mRNA encoding the Minos transposase. Integral copies of the transposon are inserted into the host genome and are stably inherited through successive generations. We have used reporter constructs to identify a muscle-specific regulatory element from Parhyale, demonstrating that this transformation vector can be used to test the activity of cis-regulatory elements in this species. The relatively high efficiency of this transgenic methodology opens new opportunities for the direct study of cis-regulatory elements and gene functions in Parhyale, allowing functional studies to be carried out beyond previously established model systems in insects.

The piggyBac (IFP2) short inverted terminal repeat transposable element from the cabbage looper Trichoplusia ni was tested for gene transfer vector function as part of a bipartite vector-helper system in the Mediterranean fruit fly Ceratitis capitata. A piggyBac vector marked with the medfly white gene was tested with a normally regulated piggyBac transposase helper at two different concentrations in a white eye host strain. Both experiments yielded transformants at an approximate frequency of 3-5%, with a total of six lines isolated having pigmented eyes with various levels of coloration. G1 transformant siblings from each line shared at least one common integration, with several sublines having an additional second integration. For the first transformant line isolated, two integrations were determined to be stable for 15 generations. For five of the lines, a piggyBac-mediated transposition was verified by sequencing the insertion site junctions isolated by inverse PCR that identified a characteristic piggyBac TTAA target site duplication. The efficient and stable transformation of the medfly with a lepidopteran vector represents transposon function over a relatively large evolutionary distance and suggests that the piggyBac system will be functional in a broad range of insects

Richard Feynman has claimed that anti-particles are nothing but particles ‘propagating backwards in time’; that time reversing a particle state always turns it into the corresponding anti-particle state. According to standard quantum field theory textbooks this is not so: time reversal does not turn particles into anti-particles. Feynman's view is interesting because, in particular, it suggests a non-standard, and possibly illuminating, interpretation of the CPT theorem. This paper explores a classical analog of Feynman's view, in the context of the recent debate between David Albert and David Malament over time reversal in classical electromagnetism. Introduction Time Reversal and the Direction of Time Classical Electromagnetism: The Story So Far 3.1The standard textbook view 3.2Albert's proposal 3.3Malament's proposal 3.4Albert revisited The ‘Feynman’ Proposal Structuralism: A Third Way? 5.1Structures: the debate recast 5.2Relational structures 5.3Malament and Feynman structures as conventional representors of a relational reality Conclusions and Open Questions

Ecological and evolutionary theory has frequently been inspired by the diversity of colour patterns on the wings of butterflies. More recently, these varied patterns have also become model systems for studying the evolution of developmental mechanisms. A technique that will facilitate our understanding of butterfly colour-pattern development is germline transformation. Germline transformation permits functional tests of candidate gene products and of cis-regulatory regions, and provides a means of generating new colour-pattern mutants by insertional mutagenesis. We report the successful transformation of the African satyrid butterfly Bicyclus anynana with two different transposable element vectors, Hermes and piggyBac, each carrying EGFP coding sequences driven by the 3XP3 synthetic enhancer that drives gene expression in the eyes. Candidate lines identified by screening for EGFP in adult eyes were later confirmed by PCR amplification of a fragment of the EGFP coding sequence from genomic DNA. Flanking DNA surrounding the insertions was amplified by inverse PCR and sequenced. Transformation rates were 5% for piggyBac and 10.2% for Hermes. Ultimately, the new data generated by these techniques may permit an integrated understanding of the developmental genetics of colour-pattern formation and of the ecological and evolutionary processes in which these patterns play a role.

I point out a simple sense in which the standard formulation of Curie's principle is false when the symmetry transformation it describes is time reversal. [PUBLICATION ABSTRACT] Reprinted by permission of the University of Chicago Press. © All rights reserved

We have developed a new plant vector system for repeated transformation (called MAT for multi-autotransformation) in which a chimeric ipt gene, inserted into the transposable element Ac, is used as a selectable marker for transformation. Selectable marker genes conferring antibiotic or herbicide resistance, used to introduce economically valuable genes into crop plants, have three major problems: (i) the selective agents have negative effects on proliferation and differentiation of plant cells; (ii) there is uncertainty regarding the environmental impact of many selectable marker genes; (iii) it is difficult to perform recurrent transformations using the same selectable marker to pyramid desirable genes. The MAT vector system containing the ipt gene and the Ac element is designed to overcome these difficulties. When tobacco leaf segments were transformed and selected, subsequent excision of the modified Ac produced marker-free transgenic tobacco plants without sexual crosses or seed production. In addition, the chimeric ipt gene could be visually used as a selectable marker for transformation of hybrid aspen (Populus sieboldii x Populus grandidentata). The chimeric ipt gene, therefore, is an attractive alternative to the most widely used selectable marker genes. The MAT vector system provides a promising way to shorten breeding time for genetically engineered crops. This method could be particularly valuable for fruit and forest trees, for which long generation times are a more significant barrier to breeding and genetic analysis

I point out that some common folk wisdom about time reversal invariance in classical mechanics is strictly incorrect, by showing some explicit examples in which classical time reversal invariance fails, even among conservative systems. I then show that there is nevertheless a broad class of familiar classical systems that are time reversal invariant.

In this paper, we show that rational homology 3-spheres are ubiquitous from the viewpoint of Heegaard splitting. Let M=H+∪FH−M=H_{+}\\cup _{F} H_{-} be a genus gg Heegaard splitting of a closed 33-manifold and cc be a simple closed curve in FF. Then there is a 3-manifold McM_{c} which is obtained from MM by horizontal Dehn surgery along cc. We show that for cc such that the homology class [c][c] is generic in the set of curve-represented homology classes Hs⊂H1(F)\\mathscr {H}_{s} \\subset H_{1}(F), rank(H1(Mc,Q))>max{1,rank(H1(M,Q)rank(H_{1}(M_{c},\\mathbb {Q}))>max \\{1,rank(H_{1}(M,\\mathbb {Q})}. As a corollary, for a set of curves {c1,c2,…,cm}\\{c_1,c_2,\\ldots , c_{m}\\}, m≥gm \\geq g, such that each [ci][c_{i}] is generic in Hs⊂H1(F)\\mathscr {H}_{s} \\subset H_{1}(F), M(c1,c2,…,cm)M_{(c_1,c_2,\\ldots , c_{m})} is a rational homology 3-sphere.

In a recent paper, Malament (2004) employs a time reversal transformation that differs from the standard one, without explicitly arguing for it. This is a new and important understanding of time reversal that deserves arguing for in its own right. I argue that it improves upon the standard one. Recent discussion has focused on whether velocities should undergo a time reversal operation. I address a prior question: What is the proper notion of time reversal? This is important, for it will affect our conclusion as to whether our best theories are time‐reversal symmetric, and hence whether our spacetime is temporally oriented.