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Ciliates are microbial eukaryotes with distinct somatic and germline genomes. Postzygotic development involves extensive remodeling of the germline genome to form somatic chromosomes. Ciliates therefore offer a valuable model for studying the architecture and evolution of programed genome rearrangements. Current studies usually focus on a few model species, where rearrangement features are annotated by aligning reference germline and somatic genomes. Although many high-quality somatic genomes have been assembled, a high-quality germline genome assembly is difficult to obtain due to its smaller DNA content and abundance of repetitive sequences. To overcome these hurdles, we propose a new pipeline, SIGAR (Split-read Inference of Genome Architecture and Rearrangements) to infer germline genome architecture and rearrangement features without a germline genome assembly, requiring only short DNA sequencing reads. As a proof of principle, 93% of rearrangement junctions identified by SIGAR in the ciliate Oxytricha trifallax were validated by the existing germline assembly. We then applied SIGAR to six diverse ciliate species without germline genome assemblies, including Ichthyophthirius multifilii, a fish pathogen. Despite the high level of somatic DNA contamination in each sample, SIGAR successfully inferred rearrangement junctions, short eliminated sequences, and potential scrambled genes in each species. This pipeline enables pilot surveys or exploration of DNA rearrangements in species with limited DNA material access, thereby providing new insights into the evolution of chromosome rearrangements.

Tujuan penelitian ini adalah untuk mengetahui apakah kemampuan pemecahan masalah matematika siswa dengan pembelajaran kooperatif Think Pair Share (TPS) berbantuan worksheet dengan menyisipkan jeda strategis scrambled mencapai ketuntasan belajar dan untuk mengetahui apakah kemampuan pemecahan masalah siswa menggunakan pembelajaran kooperatif TPS berbantuan worksheet dengan menyisipkan jeda strategis scrambled lebih tinggi daripada prestasi belajar siswa menggunakan model pembelajaran ekspositori. Populasi penelitian ini adalah semua siswa kelas VII SMP N 22 Semarang tahun pelajaran 2012/2013. Dengan teknik cluster random sampling terpilih sampel siswa kelas VII-D sebagai kelas eksperimen dan kelas VII-E sebagai kelas kontrol. Data penelitian berupa data kemampuan pemecahan masalah dengan metode tes. Data tersebut diuji dengan uji proporsi dan uji t. Hasil penelitian menunjukkan kemampuan pemecahan masalah matematika siswa dengan pembelajaran kooperatif TPS berbantuan worksheet dengan menyisipkan jeda strategis scrambled mencapai ketuntasan belajar dan kemampuan pemecahan masalah siswa dengan pembelajaran kooperatif TPS berbantuan worksheet dengan menyisipkan jeda strategis scrambled lebih tinggi dari kemampuan pemecahan masalah siswa dengan pembelajaran ekspositori. Jadi, pembelajaran kooperatif TPS berbantuan worksheet dengan menyisipkan jeda strategis scrambled efektif terhadap kemampuan pemecahan masalah matematika siswa.

Many technologies used in the classroom have the main objective to provide the teacher with support tools, for the extension and integration of the lecture. And also the objective to provide the class with a shared presentation and a tool that would improve the quality of the teaching/learning processes and the delivery of information that are produced. We report the results of a survey conducted with 163 University students who were asked to listen to a lecture accompanied by a PowerPoint presentation, prepared according to the most frequent formats. The written presentation had 3 degrees of concision/redundancy: it was fully redundant with the oral message, partially redundant (main points were selected), or had a different linguistic form (paraphrase of the message). The focus of this paper is therefore on the following question: What happens when the on-screen presentation does not correspond to the oral presentation of the lecturer, because the linguistic formulation is different and the order of presentation of the information does not match? The situation requires constant attention and concentration, giving little time to retrieve information not fully heard, understood or analyzed. In this situation, each element of disturbance is truly such, it interferes with the construction of a mental representation of the message.

In plants important questions relate to the mechanisms that control signaling between the histogenic cell layers of apical meristems and developing organs. The Arabidopsis putative atypical leucine-rich repeat receptor-like kinase STRUBBELIG (SUB) regulates amongst others floral organ shape, the plane of cell division in cells of the first subepidermal cell layer of floral meristems, ovule integument morphogenesis, and root hair patterning. Reporter assays using a functional translational fusion between SUB and EGFP indicate that SUB expression is largely confined to interior tissues in young flowers, ovules, and roots. In contrast, SUB mRNA expression can be monitored in all cell layers of those tissues. Specifically, SUB protein is not detectable in cells that show a sub mutant phenotype. Rather, SUB is detected in directly neighbouring cells in flower and ovule primordia, or in cells that are separated from mutant cells by two cell diameters in the root. Inhibitor studies corroborate a posttranscriptional regulation of SUB. Phenotypic analysis of sub-1 plants expressing a SUB:EGFP gene under the control of tissue and epidermis-specific promoters support the notion that SUB-dependent signal transduction relies on the production of secondary intercellular signals. The combined results indicate that SUB acts in a non-cell-autonomous fashion, functions in a radial inside-out signaling process, and mediates cell morphogenesis and cell fate across clonally distinct cell layers in floral primordia, developing ovules, and root meristems.