PEMANFAATAN METODE TANYA JAWAB UNTUK MENINGKATKAN KEMAMPUAN MEMBACA TEKS RECOUNT BAGI KELAS IX E DI SMP 5 KOTA SORONG TAHUN 2012

Penelitian ini bertujuan untuk mengetahui peningkatan kemampuan membaca teks recount bagi siswa Kelas IX E di SMP 5 Kota Sorong melalui pemanfaatan metode tanya jawab. Jenis penelitian ini adalah penelitian tindakan kelas (Classroom Action Research) yang dilakukan secara kolaboratif antara peneliti dengan guru. Penelitian dilaksanakan dalam dua siklus, masing-masing siklus terdiri dari empat komponen yaitu perencanaan, tindakan, pengamatan dan refleksi. Teknik pengumpulan data yang digunakan dalam penelitian ini adalah wawancara, observasi, dokumentasi dan tes. Analisis data dilakukan dalam 3 tahap yaitu reduksi, penyajian data serta menarik kesimpulan. Hasil penelitian menunjukkan bahwa: (a) pemanfaatan metode tanya jawab dapat meningkatkan partisipasi belajar siswa. Peningkatan kemampuan membaca teks recount dapat dilihat melalui aspek mendengarkan penjelasan pada siklus I sebesar 76% meningkat menjadi sebesar 100% pada siklus II. Partisipasi dalam mencatat penjelasan siklus 1 sebesar 65% meningkat menjadi sebesar 97% pada siklus II. Partisipasi dalam memperhatikan pembelajaran siklus I sebesar 62% meningkat menjadi sebesar 88% pada siklus II. Partisipasi dalam bertanya siklus I sebesar 59% meningkat menjadi sebesar 94% pada siklus II. Partisipasi dalam menjawab pertanyaan siklus I sebesar 62% meningkat menjadi sebesar 94% pada siklus II. Partisipasi dalam mengeluarkan pendapat siklus I sebesar 56% meningkat menjadi sebesar 91% pada siklus II. Partisipasi dalam menghargai pendapat teman siklus I sebesar 65% meningkat menjadi sebesar 94% pada siklus II. Partisipasi dalam menjelaskan kembali siklus I sebesar 56% meningkat menjadi sebesar 88% pada siklus II. (b) Pemanfaatan metode tanya jawab dapat meningkatkan prestasi belajar siswa. Rata-rata hasil belajar siswa pada siklus I sebesar 67 meningkat menjadi 78,5 pada siklus II. Kata kunci : metode tanya jawab, kemampuan membaca teks recount, dan SMP 5 Kota Soron

Major G-Quadruplex Form of HIV-1 LTR Reveals a (3 + 1) Folding Topology Containing a Stem-Loop

Nucleic acids can form noncanonical four-stranded structures called G-quadruplexes. G-quadruplex-forming sequences are found in several genomes including human and viruses. Previous studies showed that the G-rich sequence located in the U3 promoter region of the HIV-1 long terminal repeat (LTR) folds into a set of dynamically interchangeable G-quadruplex structures. G-quadruplexes formed in the LTR could act as silencer elements to regulate viral transcription. Stabilization of LTR G-quadruplexes by G-quadruplex-specific ligands resulted in decreased viral production, suggesting the possibility of targeting viral G-quadruplex structures for antiviral purposes. Among all the G-quadruplexes formed in the LTR sequence, LTR-III was shown to be the major G-quadruplex conformation in vitro. Here we report the NMR structure of LTR-III in K+ solution, revealing the formation of a unique quadruplex-duplex hybrid consisting of a three-layer (3 + 1) G-quadruplex scaffold, a 12-nt diagonal loop containing a conserved duplex-stem, a 3-nt lateral loop, a 1-nt propeller loop, and a V-shaped loop. Our structure showed several distinct features including a quadruplex-duplex junction, representing an attractive motif for drug targeting. The structure solved in this study may be used as a promising target to selectively impair the viral cycle

Coexistence of Wolbachia with Buchnera aphidicola and a secondary symbiont in the aphid Cinara cedri.

Intracellular symbiosis is very common in the insect world. For the aphid Cinara cedri, we have identified by electron microscopy three symbiotic bacteria that can be characterized by their different sizes, morphologies, and electrodensities. PCR amplification and sequencing of the 16S ribosomal DNA (rDNA) genes showed that, in addition to harboring Buchnera aphidicola, the primary endosymbiont of aphids, C. cedri harbors a secondary symbiont (S symbiont) that was previously found to be associated with aphids (PASS, or R type) and an alpha-proteobacterium that belongs to the Wolbachia genus. Using in situ hybridization with specific bacterial probes designed for symbiont 16S rDNA sequences, we have shown that Wolbachia was represented by only a few minute bacteria surrounding the S symbionts. Moreover, the observed B. aphidicola and the S symbionts had similar sizes and were housed in separate specific bacterial cells, the bacteriocytes. Interestingly, in contrast to the case for all aphids examined thus far, the S symbionts were shown to occupy a similarly sized or even larger bacteriocyte space than B. aphidicola. These findings, along with the facts that C. cedri harbors the B. aphidicola strain with the smallest bacterial genome and that the S symbionts infect all Cinara spp. analyzed so far, suggest the possibility of bacterial replacement in these species

Las estrategias de traducción en la película "Harry Potter y las reliquias de la muerte – parte 2"

http://www.ester.ee/record=b4693386*es

Riigi eksterritoriaalne jurisdiktsioon ja selle ulatus Euroopa Inimõiguste Kohtu praktikas

https://www.ester.ee/record=b5243798*es

Endosymbiosis morphological reorganization during metamorphosis diverges in weevils

Virtually all animals associate with beneficial symbiotic bacteria. Whether and how these associations are modulated across a host’s lifecycle is an important question in disentangling animal-bacteria interactions. We recently reported a case of complete morphological reorganization of symbiosis during metamorphosis of the cereal weevil, Sitophilus oryzae. In this model, the bacteriome, a specialized organ that houses the intracellular bacterium Sodalis pierantonius, undergoes a two-phase remodeling program synchronously driven by host and endosymbiont, resulting in a localization shift and the formation of multiple new bacteriomes. Here, we provide comparative data in a closely-related coleopteran, the red palm weevil Rhynchophorus ferrugineus, which is associated with the ancestral endosymbiont Nardonella. Using cell imaging experiments, we show that the red pal weevil bacteriome remains unchanged during metamorphosis, hence contrasting with what we reported in the cereal weevil S. oryzae. These findings highlight the complexity and divergence of host-symbiont interactions and their intertwining with host development, even in closely-related species. Abbreviations: DAPI: 4′,6-diamidino-2-phenylindole; FISH: Fluorescence in situ hybridization; T3SS: Type III secretion system

RNAi in the cereal weevil Sitophilus spp: Systemic gene knockdown in the bacteriome tissue

<p>Abstract</p> <p>Background</p> <p>The weevils <it>Sitophilus </it>spp. are among the most important cosmopolitan pests of stored cereal grains. However, their biology and physiology are poorly understood, mainly because the insect developmental stages take place within cereal grains and because of the lack of gene specific molecular manipulation.</p> <p>Results</p> <p>To gain access to the different insect developmental stages, weevil females were allowed to lay their eggs on starch pellets and hatched embryos were collected by dissolving starch with water. Embryos were transferred between two Glass Plates filled with packed Flour (GPF) to mimic compact texture of the cereal grain, and this system allowed us to recover specific developmental stages. To knockdown the gene expressed in the bacteria-bearing organ (the bacteriome), whole larvae were injected with dsRNA to target the <it>wpgrp1 </it>gene and they were then left to develop for a further 4 days period. Quantitative RT-PCR and Western blot analyses on the bacteriome of these animals revealed a down-regulation of the <it>wpgrp1 </it>expression, both at transcript and protein levels.</p> <p>Conclusion</p> <p>These results demonstrate that whole larval injection with dsRNA results in a high and systemic decrease of both mRNA and protein in the bacteriome tissue. This, along with the possibility of access to the insect developmental stages, opens up a new research avenue for exploring gene specific functions in the cereal weevils.</p

Host gene response to endosymbiont and pathogen in the cereal weevil Sitophilus oryzae

Background: Insects thriving on nutritionally poor habitats have integrated mutualistic intracellular symbiotic bacteria (endosymbionts) in a bacteria-bearing tissue (the bacteriome) that isolates the endosymbionts and protects them against a host systemic immune response. Whilst the metabolic and physiological features of long-term insect associations have been investigated in detail over the past decades, cellular and immune regulations that determine the host response to endosymbionts and pathogens have attracted interest more recently. Results: To investigate bacteriome cellular specificities and weevil immune responses to bacteria, we have constructed and sequenced 7 cDNA libraries from Sitophilus oryzae whole larvae and bacteriomes. Bioinformatic analysis of 26,886 ESTs led to the generation of 8,941 weevil unigenes. Based on in silico analysis and on the examination of genes involved in the cellular pathways of potential interest to intracellular symbiosis (i.e. cell growth and apoptosis, autophagy, immunity), we have selected and analyzed 29 genes using qRT-PCR, taking into consideration bacteriome specificity and symbiosis impact on the host response to pathogens. We show that the bacteriome tissue accumulates transcripts from genes involved in cellular development and survival, such as the apoptotic inhibitors iap2 and iap3, and endosomal fusion an

DNA structures from phosphate chemical shifts

For B-DNA, the strong linear correlation observed by nuclear magnetic resonance (NMR) between the 31P chemical shifts (δP) and three recurrent internucleotide distances demonstrates the tight coupling between phosphate motions and helicoidal parameters. It allows to translate δP into distance restraints directly exploitable in structural refinement. It even provides a new method for refining DNA oligomers with restraints exclusively inferred from δP. Combined with molecular dynamics in explicit solvent, these restraints lead to a structural and dynamical view of the DNA as detailed as that obtained with conventional and more extensive restraints. Tests with the Jun-Fos oligomer show that this δP-based strategy can provide a simple and straightforward method to capture DNA properties in solution, from routine NMR experiments on unlabeled samples

Identification of the Weevil immune genes and their expression in the bacteriome tissue

<p>Abstract</p> <p>Background</p> <p>Persistent infections with mutualistic intracellular bacteria (endosymbionts) are well represented in insects and are considered to be a driving force in evolution. However, while pathogenic relationships have been well studied over the last decades very little is known about the recognition of the endosymbionts by the host immune system and the mechanism that limits their infection to the bacteria-bearing host tissue (the bacteriome).</p> <p>Results</p> <p>To study bacteriome immune specificity, we first identified immune-relevant genes of the weevil <it>Sitophilus zeamais </it>by using suppressive subtractive hybridization (SSH) and then analyzed their full-length coding sequences obtained by RACE-PCR experiments. We then measured immune gene expression in the bacteriome, and in the aposymbiotic larvae following <it>S. zeamais </it>primary endosymbiont (SZPE) injection into the hemolymph, in order to consider the questions of bacteriome immune specificity and the insect humoral response to symbionts. We show that larval challenge with the endosymbiont results in a significant induction of antibacterial peptide genes, providing evidence that, outside the bacteriome, SZPE are recognized as microbial intruders by the host. In the bacteriome, gene expression analysis shows the overexpression of one antibacterial peptide from the <it>coleoptericin </it>family and, intriguingly, homologs to genes described as immune modulators (that is, <it>PGRP-LB, Tollip</it>) were also shown to be highly expressed in the bacteriome.</p> <p>Conclusion</p> <p>The current data provide the first description of immune gene expression in the insect bacteriome. Compared with the insect humoral response to SZPE, the bacteriome expresses few genes among those investigated in this work. This local immune gene expression may help to maintain the endosymbiont in the bacteriome and prevent its invasion into insect tissues. Further investigations of the <it>coleoptericin</it>, the <it>PGRP </it>and the <it>Tollip </it>genes should elucidate the role of the host immune system in the maintenance and regulation of endosymbiosis.</p