Robust approach to object recognition through fuzzy clustering and hough transform based methods

Object detection from two dimensional intensity images as well as three dimensional range images is considered. The emphasis is on the robust detection of shapes such as cylinders, spheres, cones, and planar surfaces, typically found in mechanical and manufacturing engineering applications. Based on the analyses of different HT methods, a novel method, called the Fast Randomized Hough Transform (FRHT) is proposed. The key idea of FRHT is to divide the original image into multiple regions and apply random sampling method to map data points in the image space into the parameter space or feature space, then obtain the parameters of true clusters. This results in the following characteristics, which are highly desirable in any method: high computation speed, low memory requirement, high result resolution and infinite parameter space. This project also considers use of fuzzy clustering techniques, such as Fuzzy C Quadric Shells (FCQS) clustering algorithm but combines the concept of noise prototype to form the Noise FCQS clustering algorithm that is robust against noise. Then a novel integrated clustering algorithm combining the advantages of FRHT and NFCQS methods is proposed. It is shown to be a robust clustering algorithm having the distinct advantages such as: the number of clusters need not be known in advance, the results are initialization independent, the detection accuracy is greatly improved, and the computation speed is very fast. Recent concepts from robust statistics, such as least trimmed squares estimation (LTS), minimum volume ellipsoid estimator (MVE) and the generalized MVE are also utilized to form a new robust algorithm called the generalized LTS for Quadric Surfaces (GLTS-QS) algorithm is developed. The experimental results indicate that the clustering method combining the FRHT and the GLTS-QS can improve clustering performance. Moreover, a new cluster validity method for circular clusters is proposed by considering the distribution of the points on the circular edge. Different methods for the computation of distance of a point from a cluster boundary, a common issue in all the range image clustering algorithms, are also discussed. The performance of all these algorithms is tested using various real and synthetic range and intensity images. The application of the robust clustering methods to the experimental granular flow research is also included

Long first exons and epigenetic marks distinguish conserved pachytene piRNA clusters from other mammalian genes

In the male germ cells of placental mammals, 26-30-nt-long PIWI-interacting RNAs (piRNAs) emerge when spermatocytes enter the pachytene phase of meiosis. In mice, pachytene piRNAs derive from ~100 discrete autosomal loci that produce canonical RNA polymerase II transcripts. These piRNA clusters bear 5\u27 caps and 3\u27 poly(A) tails, and often contain introns that are removed before nuclear export and processing into piRNAs. What marks pachytene piRNA clusters to produce piRNAs, and what confines their expression to the germline? We report that an unusually long first exon ( \u3e /= 10 kb) or a long, unspliced transcript correlates with germline-specific transcription and piRNA production. Our integrative analysis of transcriptome, piRNA, and epigenome datasets across multiple species reveals that a long first exon is an evolutionarily conserved feature of pachytene piRNA clusters. Furthermore, a highly methylated promoter, often containing a low or intermediate level of CG dinucleotides, correlates with germline expression and somatic silencing of pachytene piRNA clusters. Pachytene piRNA precursor transcripts bind THOC1 and THOC2, THO complex subunits known to promote transcriptional elongation and mRNA nuclear export. Together, these features may explain why the major sources of pachytene piRNA clusters specifically generate these unique small RNAs in the male germline of placental mammals

Genome-wide characterization of GRAS family genes in Medicago truncatula reveals their evolutionary dynamics and functional diversification.

The GRAS gene family is a large plant-specific family of transcription factors that are involved in diverse processes during plant development. Medicago truncatula is an ideal model plant for genetic research in legumes, and specifically for studying nodulation, which is crucial for nitrogen fixation. In this study, 59 MtGRAS genes were identified and classified into eight distinct subgroups based on phylogenetic relationships. Motifs located in the C-termini were conserved across the subgroups, while motifs in the N-termini were subfamily specific. Gene duplication was the main evolutionary force for MtGRAS expansion, especially proliferation of the LISCL subgroup. Seventeen duplicated genes showed strong effects of purifying selection and diverse expression patterns, highlighting their functional importance and diversification after duplication. Thirty MtGRAS genes, including NSP1 and NSP2, were preferentially expressed in nodules, indicating possible roles in the process of nodulation. A transcriptome study, combined with gene expression analysis under different stress conditions, suggested potential functions of MtGRAS genes in various biological pathways and stress responses. Taken together, these comprehensive analyses provide basic information for understanding the potential functions of GRAS genes, and will facilitate further discovery of MtGRAS gene functions

The evolutionarily conserved piRNA-producing locus pi6 is required for male mouse fertility

Pachytene PIWI-interacting RNAs (piRNAs), which comprise \u3e 80% of small RNAs in the adult mouse testis, have been proposed to bind and regulate target RNAs like microRNAs, cleave targets like short interfering RNAs or lack biological function altogether. Although piRNA pathway protein mutants are male sterile, no biological function has been identified for any mammalian piRNA-producing locus. Here, we report that males lacking piRNAs from a conserved mouse pachytene piRNA locus on chromosome 6 (pi6) produce sperm with defects in capacitation and egg fertilization. Moreover, heterozygous embryos sired by pi6(-/-) fathers show reduced viability in utero. Molecular analyses suggest that pi6 piRNAs repress gene expression by cleaving messenger RNAs encoding proteins required for sperm function. pi6 also participates in a network of piRNA-piRNA precursor interactions that initiate piRNA production from a second piRNA locus on chromosome 10, as well as pi6 itself. Our data establish a direct role for pachytene piRNAs in spermiogenesis and embryo viability

Application of "Problem Solving" in Religious Educatiion

Anglická anotace (English annotation) Application of the "Problem solving" to the Religious education This dissertation work deals with the practical application of teaching methods "problem solving" in the lessons of religion with all its pros and cons. It deals with issues in the teaching of religious education 8th classes of elementary schools, using only the Czech language and suggested topics, which are set out in the curriculum of religious education Roman Catholic Church in 2004, for use in the diocese of Hradec Králové. The first part is devoted to learning theory, regulations, curriculum and teaching plans of the relevant legislation with regard to the specifics and the territorial limits. The following section presents the individual applicable methods in the "problem solving" with respect to the development of key competencies of students. And in the last section are selected appropriate methods discussed in details and presented on topics discussed in the teaching of religious education lessons. The course of instruction and the subsequent reactions of students and teachers alike are drawn appropriate recommendations to the methods already fully applicable. In conclusion, the proper methods for teaching religious education in the 8th elementary school classroom are described in detail for any..

MOESM5 of Switchgrass SBP-box transcription factors PvSPL1 and 2 function redundantly to initiate side tillers and affect biomass yield of energy crop

Additional file 5: Figure S3.  Expression levels of PvSPL1 in PvSPL1SRDX and rPvSPL1 overexpressing transgenic switchgrass plants were revealed by qRT-PCR. Switchgrass Ubq2 was used as the reference for normalization. PvSPL1: sum of exo- and endo-PvSPL1 transcript versions

MOESM4 of Switchgrass SBP-box transcription factors PvSPL1 and 2 function redundantly to initiate side tillers and affect biomass yield of energy crop

Additional file 4: Figure S2. Relationships between expression levels of the miR156-targeted PvSPL genes and tiller numbers. Twelve independent positive miR156 overexpressing transgenic switchgrass lines were generated by Agrobacterium-mediated transformation. Expression levels of PvSPL1/19, 2/18, 3/5, and 6/7 in the transgenic switchgrass plants were detected by qRT-PCR. Switchgrass Ubq2 was used as the reference for normalization

MOESM7 of Switchgrass SBP-box transcription factors PvSPL1 and 2 function redundantly to initiate side tillers and affect biomass yield of energy crop

Additional file 7: Table S4. Primer sequences used for gene expression analysis by qRT-PCR and plasmid construction

Comparative analysis of expression profiles of duplicated <i>MtGRAS</i> genes.

<p>The X-axis represents different tissues of <i>M</i>. <i>truncatula</i>. The Y-axis shows the expression values (FPKM) obtained using RNA-seq data.</p