Perangkat Pembelajaran Fisika SMA Berkarakter Kelas X

Perangkat Pembelajaran Fisika Kelas X [Download]

Suharlan SH, MM, Prestasi OSN di Tiap Daerah Harus Merata

Melalui OSP yang mengerucut pada OSN, PLH Kasubdit Kelembagaan dan Peserta Didik, Suharlan SH, MM berharap semua Dinas Kebupaten Kota mengapresiasi kegiatan-kegiatan olimpiade sains, mulai dari  tingkat Kabupaten Kota, Provinsi hingga Nasional. Proses seleksi dan mekanisme yang berlangsung selama ini sudah berjalan dengan baik dan Dinas Kabupaten Kota juga menyambut baik dengan menganggarkan dana APBD sehingga kompetisi ini betul-betul selektif dan bergengsi.
“OSN merupakan kebanggaan peserta didik, sekolah dan orang tua. Siswa yang berhasil lolos di tingkat Kabupaten Kota saja sudah membuat mereka dan juga orang tuanya bangga, apalagi jika lolos hingga tingkat provinsi, nasional, atau bahkan internasional. Rasa bangga itu bukan lagi menjadi hal yang mutlak, namun telah berbaur dengan rasa haru sebab dapat membawa nama Indonesia di kancah olimpiade sains tingkat internasional.” Tambah Suharlan.

Pada OSN kali ini semua sekolah diberi kesempatan yang sama untuk berperan serta, baik itu sekolah swasta maupun negeri. Jadi tidak ada prioritas pada sekolah tertentu, dan kegiatan ini tidak didominasi oleh sekolah-sekolah yang bagus saja, sekolah yang berada di pelosok pun memeroleh kesempatan yang sama untuk berkompetisi di tingkat nasional maupun internasional. Dan budaya ini sudah mulai dirasakan manfaatnya baik bagi siswa, sekolah maupun Dinas Kabupaten Kota. Karena OSN merupakan kegiatan yang penseleksiannya berjenjang, mulai dari tingkat sekolah, Kabupaten/Kota, Provinsi hingga Nasional, event ini sudah sesuai dengan kebijakan pemerintah di dalam Peraturan Menteri bahwa kegiatan-kegiatan kompetisi yang perlu ditingkatkan. Kami berharap pemenang di tingkat Kabupaten Kota, khususnya Bupati dan Walikota dapat memberikan apresiasi kepada para siswa yang turut dalam olimpiade tersebut dan ini sesuai dengan Peraturan menteri di mana intansi terkait memiliki kewenangan untuk memberikan penghargaan dan care kepada mereka. Olimpade sains bidang studi ini bukan hal yang menakutkan lagi, dan peserta sudah merasa ‘enjoy’ dengan bidang studi yang diminati. Contohnya bidang studi kimia, di situ para peserta terlihat betul menikmati pelajaran tersebut dan budaya untuk meneliti melalui laboratorium-laboratorium kimia kini semakin diminati siswa.

Menghadapi OSN tahun ini masing-masing Kabupaten Kota sudah mulai mempersiapkan diri sebelum maju ke tingkat provinsi. Begitu pun ke tingkat nasional, tiap provinsi  juga telah menyiapkan timnya dengan persiapan yang matang melalui kompetisi-kompetisi yang mereka adakan sebelumnya. “Kabupaten Kota dan Provinsi telah menyalurkan dana untuk kegiatan ini. Jadi keseriusan mereka pada dunia pendidikan di Indonesia tampak jelas dan ini merupakan gejala positif sehingga  sistem yang kita bangun semakin lama semakin berkembang. OSN yang semula dianggap sebagai esklufisme sekarang sudah tidak lagi. Itu yang penting. Bahkan sekolah-sekolah dari daerah pun sudah berani berkompetisi.” Papar Suharlan. “Kami menghimbau agar tiap sekolah  melakukan pembinaan secara intensif sebelum mengirimkan siswa-siswinya ke tingkat nasional. Semoga kegiatan ini dapat berjalan sukses dan memeroleh ilmuwan-ilmuwan muda yang siap berlomba di tingkat internasional,” lanjutnya. Sukses untuk para peserta. Rinda/Fanny

http://siswapsma.org/index.php?option=com_content&view=article&id=208:prestasi-osn-di-tiap-daerah-harus-merata&catid=38:osn&Itemid=65

 

Olimpiade Sains Provinsi 2012, Siswa SMA Se-Indonesia Unjuk Prestasi di Bidang Sains

Lebih dari 13.000 siswa-siswi terbaik yang mewakili masing-masing kabupaten/kota di seluruh Indonesia unjuk prestasi dalam olimpiade sains tingkat provinsi. Mereka terpilih setelah sebelumnya mengikuti seleksi olimpiade sains di tingkat kabupaten/kota pada 4 – 5 April 2012. Pelaksanaan seleksi Olimpiade Sains Provinsi (OSP) 2012 diselenggarakan serentak pada tanggal 5 – 6 Juni 2012 di 33 provinsi. OSP kali ini akan melombakan delapan bidang studi, yaitu matematika, fisika, kimia, biologi, komputer, astronomi, ekonomi, dan kebumian (geo sains).
Peserta yang sukses berkompetisi di tingkat provinsi, selanjutnya akan berlaga dalam perhelatan akbar Olimpiade Sains Nasional (OSN) yang akan diselenggarakan di Jakarta, pada 2 - 7 September 2012. Peraih medali pada OSN 2012 akan diseleksi melalui pembinaan bertahap untuk mewakili Indonesia di ajang olimpiade sains internasional 2013.

PLH Kasubdit Kelembagaan dan Peserta Didik Direktorat Pembinaan SMA, Suharlan SH menyampaikan, tujuan dari rangkaian kegiatan olimpiade sains secara berjenjang ini adalah untuk menjaring siswa-siswi yang memiliki potensi, khususnya di bidang sains. Selain itu diharapkan mereka dapat menumbuhkan budaya kompetitif yang sehat, meningkatkan wawasan pengetahuan, “Setiap siswa memeroleh kesempatan dan peluang yang sama untuk meraih prestasi di ajang olimpiade sains, mulai dari tingkat kabupaten hingga nasional. Mereka diharapkan mampu berkompetisi di delapan bidang studi yang dilombakan. Dengan demikian, peningkatan prestasi bisa tercapai di tiap daerah,” ujar Suharlan.

 

http://siswapsma.org/index.php?option=com_content&view=article&id=207:olimpiade-sains-provinsi-2012&catid=38:osn&Itemid=65

 

Kisi-Kisi dan Materi Uji Olimpiade Sains SMA Bidang Informatika/Komputer Tahun 2012

Bundel pembahasan soal Olimpiade Sains Informatika berisi kumpulan soal dari OSK, OSP, dan OSN tahun 2010-2011 (+OSK 2012) yang telah dipilih dan dikategorikan sesuai dengan jenis soalnya, disertai dengan tingkat kesulitannya. Bundel pembahasan soal ini ditujukan untuk pembimbing dan peserta yang kesulitan mencari materi mengenai persiapan Olimpiade Sains Informatika.

Untuk mengunduh materi-materi di atas silahkan klik pilihan di bawah ini.

• Bundel_Pembahasan_Soal_Olimpiade_Sains_Informatika
• Kisi-kisi & Materi Uji Olimpiade Sains   

source : http://pdkjateng.go.id/

6 Juni 2012, Transit Venus (Gerhana Venus) Terakhir Abad Ini

 

 Daerah yang dapat melihat fenomena Transit Venus (gerhana Venus) 6 Juni 2012. Image credit: scitechdaily.com

Rabu 6 Juni 2012, planet Venus akan melintas di depan Matahari dan akan menghasilkan bayangan yang mana tidak ada seorang pun yang hidup hari ini akan melihat lagi fenomena ini dalam hidupnya, sebab fenomena transit Venus ini kemungkinan baru akan kembali hadir pada tahun 11 Desember 2117 nanti, lama sekali bukan. Kita beruntung sebab fenoena transit Venus ini akan dapat dilihat di 7 benua termasuk antartika. Kemungkinan transit Venus ini akan berlangsung selama 7 jam.

Seperti Gerhana Matahari, untuk melihat transit Venus ini kita diharuskan menggunakan pelindung mata, sebab cahaya Matahari dapat merusak Retina kita jika kita melihatnya secara langsung tanpa perlindungan. Fenomena transit Venus ini juga bisa disebut sebagai Gerhana Venus. (Adi Saputro/ astronomi.us) 

http://www.astronomi.us/2012/06/6-juni-2012-transit-venus-gerhana-venus.html

Northern Lights Process Like Untangling Twisted Strands of Spaghetti?

ScienceDaily (June 1, 2012) — A University of Iowa researcher wants you to visualize a plate of spaghetti when you think of the northern lights.

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Diffuse gas—called plasma—flows outward from the sun as the “solar wind” and carries with it solar magnetic field lines that become entangled with the Earth's own magnetic field lines. Location of "holes" were detected in indicated pink layers, near Earth. (Credit: Image courtesy of NASA.)

That's because Jack Scudder, UI professor of physics and astronomy, and his colleagues have reached a milestone in describing how the northern lights work by way of a process called "magnetic reconnection."

The details are contained in a paper published in the June 5 issue of the journal Physical Review Letters; however, the process is best imagined as untangling twisted strands of spaghetti.

Diffuse gas -- called plasma -- flows outward from the sun as the "solar wind" and carries with it magnetic field lines ("spaghetti") from the sun.

The entanglement between magnetic field lines (spaghetti) from the sun and other field lines (spaghetti) anchored in Earth's core occurs when these field lines are brought together by gusts of solar wind.

"In the process of smoothing this entanglement, one or more holes are created that now link field lines, with one originating in the sun and the other in the Earth's metallic core," says Scudder. "This linkage allows charged particles to cross a previously forbidden boundary that separates the Earth's volume from the sun's. The formation of these inter-connections represents a stress reduction. The aurorae are a byproduct of this change in how the strands of spaghetti are connected, since with the hole, charged particles from the sun are now allowed access into the atmosphere below the Earth's magnetic shield."

One result is the beautiful colors of the northern lights. "Most effects of solar weather that have an earthly influence gain entrance through holes of this type that are in place when a solar disturbance hits," Scudder says. "In this sense the sites of reconnection are the 'keyholes' for the intrusion of solar weather into near Earth space.

"After more than 30 years of research, my colleagues and I have announced a milestone discovery in astrophysics -- the first experimentally resolved and unequivocal site of collision -- less magnetic reconnection, in which magnetic field energy is converted into energetic particles," Scudder says. "When this process occurs, previously separated volumes of space become interconnected by magnetic fields, providing new highways for the prompt interchange of high temperature gases."

Because magnetic reconnection is thought to occur elsewhere in the universe, Scudder and his colleagues are delighted to have observed evidence of a hard-to-see hole.

In astronomical terms, the size of a hole is relatively small -- about 1 kilometer in diameter seen at a distance of 57,000 kilometers from Earth. If magnetic reconnection were occurring on the surface of the sun, at another star, or at a planet in another solar system, scientists would never be able to see it, Scudder says. Consequently, Scudder's work is all the more important because it serves to "bench test," or prove, an astrophysical process that humankind will never be able to directly corroborate in deep space.

In addition to being small, the hole Scudder observed was in constant motion.

Because the hole was in an unknown state of motion relative to the spacecraft, it could have been traversed many times previously without having been detected. To correct for this situation, researchers developed new techniques to reduce the time interval between "snapshots" by a factor of 11 using the same detector and without flying a new detector.

"This 'trick' is like having access to a microscope for the first time to re-examine data that was thought to have been acquired too slowly to find these holes. Resolving these holes in magnetic fields is somewhat similar to looking at stagnant water through a microscope for the first time and seeing the writhing molecular behavior that was only suspected previously," he says.

Scudder and his colleagues were able to observe the magnetic reconnection site in space by using data from NASA's Polar spacecraft and its Hydra, MFE and EFI experiments. Scudder says the process he observed is active not just in creating the northern lights, but many other astronomical phenomena as well.

"The experimental documentation of the physical process that enables this phenomenon provides the first support of the prevailing theories for explaining the production of solar flares, x-rays from black holes, as well as the causes of the aurorae that brilliantly light up the polar skies," he says.

The manner in which Scudder and his associates made the landmark observation involved five different comparisons across three independent detectors to reinforce the detection, similar to the teamwork involved in professional sports.

As part of NASA's Polar/Hydra program at the UI, data from three separate experiments were shown to reproduce the extreme signatures predicted by computer models of the process. These signatures were so unusual that nothing approaching their extremes had been recorded in 50 years of space research. Using the largest computer resources at NASA, the National Science Foundation, and the U.S. Department of Energy, the reference computer models solved six trillion equations of motion in order to predict the observations for the three experiments.

By showing scientists what combinations of observations can help identify these regions, Scudder's work will save time and energy for researchers preparing to explore magnetic reconnection in detail by using NASA's Magnetospheric Multi-Scale (MMS) mission set for launch in 2014.

Scudder's collaborators and co-authors include UI graduate students R.D. Holdaway and J.Y. Lopez. His other colleagues are H. Karimabadi and V. Roytershteyn of the University of California, San Diego; W.S. Daughton of the Los Alamos National Laboratory, N.M.; and C.T. Russell of UCLA.

The UI Department of Physics and Astronomy is part of the College of Liberal Arts and Sciences.

The research was funded in part by grants from NASA, the National Science Foundation, and the U.S. Department of Energy.

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Journal Reference:

1. J. D. Scudder, R. D. Holdaway, W. S. Daughton, H. Karimabadi, V. Roytershteyn, C. T. Russell, and J. Y. Lopez. First Resolved Observations of the Demagnetized Electron-Diffusion Region of an Astrophysical Magnetic-Reconnection Site. Phys. Rev. Lett., June 1, 2012 DOI: 10.1103/PhysRevLett.108.225005

Expanding the Genetic Alphabet May Be Easier Than Previously Thought

ScienceDaily  — A new study led by scientists at The Scripps Research Institute suggests that the replication process for DNA -- the genetic instructions for living organisms that is composed of four bases (C, G, A and T) -- is more open to unnatural letters than had previously been thought. An expanded "DNA alphabet" could carry more information than natural DNA, potentially coding for a much wider range of molecules and enabling a variety of powerful applications, from precise molecular probes and nanomachines to useful new life forms.

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 A new study led by scientists at The Scripps Research Institute suggests that the replication process for DNA -- the genetic instructions for living organisms that is composed of four bases (C, G, A and T) -- is more open to unnatural letters than had previously been thought. (Credit: © Dmitry Sunagatov / Fotolia)

The new study, which appears in the June 3, 2012 issue of Nature Chemical Biology, solves the mystery of how a previously identified pair of artificial DNA bases can go through the DNA replication process almost as efficiently as the four natural bases.

"We now know that the efficient replication of our unnatural base pair isn't a fluke, and also that the replication process is more flexible than had been assumed," said Floyd E. Romesberg, associate professor at Scripps Research, principal developer of the new DNA bases, and a senior author of the new study. The Romesberg laboratory collaborated on the new study with the laboratory of co-senior author Andreas Marx at the University of Konstanz in Germany, and the laboratory of Tammy J. Dwyer at the University of San Diego.

Adding to the DNA Alphabet

Romesberg and his lab have been trying to find a way to extend the DNA alphabet since the late 1990s. In 2008, they developed the efficiently replicating bases NaM and 5SICS, which come together as a complementary base pair within the DNA helix, much as, in normal DNA, the base adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G).

The following year, Romesberg and colleagues showed that NaM and 5SICS could be efficiently transcribed into RNA in the lab dish. But these bases' success in mimicking the functionality of natural bases was a bit mysterious. They had been found simply by screening thousands of synthetic nucleotide-like molecules for the ones that were replicated most efficiently. And it had been clear immediately that their chemical structures lack the ability to form the hydrogen bonds that join natural base pairs in DNA. Such bonds had been thought to be an absolute requirement for successful DNA replication‑ -- a process in which a large enzyme, DNA polymerase, moves along a single, unwrapped DNA strand and stitches together the opposing strand, one complementary base at a time.

An early structural study of a very similar base pair in double-helix DNA added to Romesberg's concerns. The data strongly suggested that NaM and 5SICS do not even approximate the edge-to-edge geometry of natural base pairs -- termed the Watson-Crick geometry, after the co-discoverers of the DNA double-helix. Instead, they join in a looser, overlapping, "intercalated" fashion. "Their pairing resembles a 'mispair,' such as two identical bases together, which normally wouldn't be recognized as a valid base pair by the DNA polymerase," said Denis Malyshev, a graduate student in Romesberg's lab who was lead author along with Karin Betz of Marx's lab.

Yet in test after test, the NaM-5SICS pair was efficiently replicable."We wondered whether we were somehow tricking the DNA polymerase into recognizing it," said Romesberg. "I didn't want to pursue the development of applications until we had a clearer picture of what was going on during replication."

Edge to Edge

To get that clearer picture, Romesberg and his lab turned to Dwyer's and Marx's laboratories, which have expertise in finding the atomic structures of DNA in complex with DNA polymerase. Their structural data showed plainly that the NaM-5SICS pair maintain an abnormal, intercalated structure within double-helix DNA -- but remarkably adopt the normal, edge-to-edge, "Watson-Crick" positioning when gripped by the polymerase during the crucial moments of DNA replication.

"The DNA polymerase apparently induces this unnatural base pair to form a structure that's virtually indistinguishable from that of a natural base pair," said Malyshev.

NaM and 5SICS, lacking hydrogen bonds, are held together in the DNA double-helix by "hydrophobic" forces, which cause certain molecular structures (like those found in oil) to be repelled by water molecules, and thus to cling together in a watery medium. "It's very possible that these hydrophobic forces have characteristics that enable the flexibility and thus the replicability of the NaM-5SICS base pair," said Romesberg. "Certainly if their aberrant structure in the double helix were held together by more rigid covalent bonds, they wouldn't have been able to pop into the correct structure during DNA replication."

An Arbitrary Choice?

The finding suggests that NaM-5SICS and potentially other, hydrophobically bound base pairs could some day be used to extend the DNA alphabet. It also hints that Evolution's choice of the existing four-letter DNA alphabet -- on this planet -- may have been somewhat arbitrary. "It seems that life could have been based on many other genetic systems," said Romesberg.

He and his laboratory colleagues are now trying to optimize the basic functionality of NaM and 5SICS, and to show that these new bases can work alongside natural bases in the DNA of a living cell.

"If we can get this new base pair to replicate with high efficiency and fidelity in vivo, we'll have a semi-synthetic organism," Romesberg said. "The things that one could do with that are pretty mind blowing."

The other contributors to the paper, "KlenTaq polymerase replicates unnatural base pairs by inducing a Watson-Crick geometry," are Thomas Lavergne of the Romesberg lab, Wolfram Welte and Kay Diederichs of the Marx lab, and Phillip Ordoukhanian of the Center for Protein and Nucleic Acid Research at The Scripps Research Institute.

The study was supported in part by a grant from the National Institutes of Health.

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Journal Reference:

1. Karin Betz, Denis A Malyshev, Thomas Lavergne, Wolfram Welte, Kay Diederichs, Tammy J Dwyer, Phillip Ordoukhanian, Floyd E Romesberg & Andreas Marx. KlenTaq polymerase replicates unnatural base pairs by inducing a Watson-Crick geometry. Nature Chemical Biology, 03 June 2012 DOI: 10.1038/nchembio.966