Meningkatkan Hasil Belajar Siswa Kelas IV SDN Manggalai Dalam Pembelajaran IPA Khususnya Materi Gaya Melalui Pendekatan Inkuiri

Tujuan penelitian ini untuk mengetahui penerapan pendekatan inkuiri dalam pembelajaran IPA khususnya materi gaya untuk meningkatkan hasil belajar siswa kelas IV SDN Manggalai. Rancangan penelitian tindakan kelas ini dilakukan dalam dua siklus dan setiap siklus terdiri dari empat tahap yaitu (1) perencanaan (2) Pelaksanaan (3) observasi (4) refleksi. Pengumpulan data melalui teknik pemberian tes, wawancara, observasi dan pencatatan lapangan. Analisis data dilakukan melalui reduksi, penyajian dan penarikan kesimpulan. Subjek penelitian ini adalah siswa kelas IV SDN Manggalai yang berjumlah 20 orang siswa. Hasil penelitian diperoleh data awal siswa yang kategori tuntas 4 orang atau persentase ketuntasan klasikal 20%. Pada siklus 1 banyak siswa yang tuntas 10 orang persentase ketuntasan klasikal 50%. Sedangkan Siklus II banyaknya siswa yang tuntas 19 orang, persentase ketuntasan klasikal 95%. Hasil penelitian tersebut menunjukkan bahwa pendekatan inkuiri dapat meningkatkan hasil belajar

The `Parahippocampal Place Area' Responds Selectively to High Spatial Frequencies

Defining the exact mechanisms by which the brain processes visual objects and scenes remains an unresolved challenge. Valuable clues to this process have emerged from the demonstration that clusters of neurons (“modules”) in inferior temporal cortex apparently respond selectively to specific categories of visual stimuli, such as places/scenes. However, the higher-order “category-selective” response could also reflect specific lower-level spatial factors. Here we tested this idea in multiple functional MRI experiments, in humans and macaque monkeys, by systematically manipulating the spatial content of geometrical shapes and natural images. These tests revealed that visual spatial discontinuities (as reflected by an increased response to high spatial frequencies) selectively activate a well-known place-selective region of visual cortex (the “parahippocampal place area”) in humans. In macaques, we demonstrate a homologous cortical area, and show that it also responds selectively to higher spatial frequencies. The parahippocampal place area may use such information for detecting object borders and scene details during spatial perception and navigation.National Institutes of Health (U.S.) (NIH Grant R01 MH6752)National Institutes of Health (U.S.) (grant R01 EY017081)Athinoula A. Martinos Center for Biomedical ImagingNational Center for Research Resources (U.S.)Mind Research Institut

The F-box protein FBXO45 promotes the proteasome-dependent degradation of p73

The transcription factor p73, a member of the p53 family, mediates cell-cycle arrest and apoptosis in response to DNA damage-induced cellular stress, acting thus as a proapoptotic gene. Similar to p53, p73 activity is regulated by post-translational modification, including phosphorylation, acetylation and ubiquitylation. In C. elegans, the F-box protein FSN-1 controls germline apoptosis by regulating CEP-1, the single ancestral p53 family member. Here we report that FBXO45, the human ortholog of FSN-1, binds specifically to p73 triggering its proteasome-dependent degradation. Importantly, SCF(FBXO45) ubiquitylates p73 both in vivo and in vitro. Moreover, siRNA-mediated depletion of FBXO45 stabilizes p73 and concomitantly induces cell death in a p53-independent manner. All together, these results show that the orphan F-box protein FBXO45 regulates the stability of p73, highlighting a conserved pathway evolved from nematode to human by which the p53 members are regulated by an SCF-dependent mechanism