PENGEMBANGAN MODUL PEMBELAJARAN FISIKA BERBASIS KERJA LABORATORIUM DENGAN PENDEKATAN SCIENCE PROCESS SKILLS (SPS) UNTUK MENINGKATKAN ACADEMIC PERFORMANCE RANAH KOGNITIF DAN PSIKOMOTOR

Penelitian ini bertujuan untuk (1) mengetahui bahwa pengembangan modul pembelajaran fisika berbasis kerja laboratorium dengan pendekatan Science Process Skills (SPS) bisa digunakan dalam pembelajaran fisika di sekolah; (2) mengetahui bahwa pengembangan modul pembelajaran fisika berbasis kerja laboratorium dapat meningkatkan academic performance ranah kognitif siswa; (3) mengetahui bahwa pengembangan modul pembelajaran fisika berbasis kerja laboratorium dapat meningkatkan academic performance ranah psikomotor siswa. Penelitian ini merupakan jenis penelitian Research and Development (R &D). Objek dari penelitian ini adalah 31 siswa kelas X MIA 2 di SMA N 1 Kasihan, Bantul. Hasil pengamatan berupa nilai pretest dan posttest siswa untuk penilaian kognitif serta penilaian psikomotor siswa selama mengikuti pembelajaran dengan modul berbasis kerja laboratorium berdasarkan penilaian dari observer. Hasil penelitian menunjukkan bahwa (1) Modul fisika berbasis kerja laboratorium yang telah dikembangkan bisa digunakan dalam pembelajaran fisika di sekolah sesuai dengan penilaian dari dosen ahli dalam kategori baik; (2) Modul fisika berbasis kerja laboratorium yang telah dikembangkan dapat meningkatkan academic performance ranah kognitif siswa; (3) Modul fisika berbasis kerja laboratorium yang telah dikembangkan dapat meningkatkan academic performance ranah psikomotor siswa. Berdasarkan hasil olahan data dapat ditarik kesimpulan bahwa terdapat peningkatan academic performance ranah kognitif siswa dengan nilai gain 0,644 yang berarti peningkatan dalam kategori sedang. Untuk academic performance ranah psikomotor siswa adalah dalam kategori sangat baik. Kata kunci: kerja laboratorium, Scince Process Skills (SPS), ranah kognitif, ranah psikomoto

A Spitzer Study of Comets 2P/Encke, 67P/Churyumov-Gerasimenko, and C/2001 HT50 (LINEAR-NEAT)

We present infrared images and spectra of comets 2P/Encke, 67P/Churyumov-Gerasimenko, and C/2001 HT50 (LINEAR-NEAT) as part of a larger program to observe comets inside of 5 AU from the sun with the Spitzer Space Telescope. The nucleus of comet 2P/Encke was observed at two vastly different phase angles (20 degrees and 63 degrees). Model fits to the spectral energy distributions of the nucleus suggest comet Encke's infrared beaming parameter derived from the near-Earth asteroid thermal model may have a phase angle dependence. The observed emission from comet Encke's dust coma is best-modeled using predominately amorphous carbon grains with a grain size distribution that peaks near 0.4 microns, and the silicate contribution by mass to the sub-micron dust coma is constrained to 31%. Comet 67P/Churyumov-Gerasimenko was observed with distinct coma emission in excess of a model nucleus at a heliocentric distance of 5.0 AU. The coma detection suggests that sublimation processes are still active or grains from recent activity remain near the nucleus. Comet C/2001 HT50 (LINEAR-NEAT) showed evidence for crystalline silicates in the spectrum obtained at 3.2 AU and we derive a silicate-to-carbon dust ratio of 0.6. The ratio is an order of magnitude lower than that derived for comets 9P/Tempel 1 during the Deep Impact encounter and C/1995 O1 (Hale-Bopp).Comment: Accepted for publication in the Astrophysical Journal 48 pages, 15 figures, 10 table

Toxicology of Lapachol in rats: embryolethality

Lapachol is a naphtoquinone with therapeutic potential against enterovirus, Chagas disease and is also used as an antimalarial and antiinflamatory agent. In order to study teratogenic potential of Lapachol, pregnant Wistar rats were treated with 0.5 ml of distilled water (control group); 0.5 ml of hydroalcoholic solution (vehicle group) and 10 mg of Lapachol in 0.5 ml of hydroalcoholic solution (treated group) by oral gavage from the 8th to the 12th day of pregnancy. The following variables were observed: maternal body weight on days 1, 6, l5 and 21 and food intake on days 2, 6, 15 and 21 of pregnancy. The number of live and dead fetuses and the sites of resorptions were counted. The ovaries were weighed and the corpora lutea were counted. Data were analyzed by ANOVA-one way, Dunnett test and the chi square test. Significance level test a = 0.05. Results have shown that mothers were unaffected but there were a 99.2% of fetus mortality, indicative of a strong abortifacient effect of Lapachol in rats.O Lapachol é uma naftoquinona com potencial terapêutico contra enterovírus, doença de Chagas e como antimalárico. Para estudar o potencial embriotóxico do Lapachol, ratas originalmente Wistar, grávidas, foram tratadas com 0,5 ml de água destilada (grupo controle); 0,5 ml de solução hidroalcoólica (grupo veículo) e 10 mg de Lapachol em 0,5 ml de solução hidroalcoólica (grupo tratado) por gavage, do 8o ao 12o dia de gestação. As seguintes variáveis foram observadas: peso corporal materno nos dias 1, 6, 15 e 21, consumo de ração nos dias 2, 6, 15 e 21 de gestação. O número de fetos vivos e mortos e os locais de reabsorção foram contados. Os ovários foram pesados e os corpos lúteos, contados. Os dados foram analisados por ANOVA "one way", teste de Dunnet e Qui-quadrado. O nível de significância dos testes foi a = 0,05. Os resultados mostram que as mães não foram afetadas, mas ocorreram 99,2% de mortes fetais, o que indica um potente efeito embriotóxico do Lapachol para o rato

A model for the development of programming courses to promote the participation of young women in STEM

There is a gender gap in science, technology, engineering, and mathematics (STEM), and this is a global problem that affects society. However, it is worth pointing out that the gap is not uniform in all STEM fields. Women’s underrepresentation is more marked in physics, engineering, and computer science fields. Nowadays, the labor market is becoming more competitive, technology-based and demands a diverse workforce. Therefore, it is important to continue promoting the participation of women in STEM, and the universities play a leading role in it. Previous research has shown that early learning experiences in STEM can show female students that they can succeed in this fields. This paper describes a model for developing programming courses for pre-university students to promote the participation of young women in STEM programs. The course was developed in one week, 25 students (16 girls and 9 boys) participated. The instructors of the course were four female professors. The programming language was Python, and the methodology used case-based learning. Both instructors and students gave positive comments on their experience in the course. The proposed model, including instruments, learning resources, and methodology, can be replicated and adapted to be used even in other learning field

A Photometric Method for Quantifying Asymmetries in Disk Galaxies

A photometric method for quantifying deviations from axisymmetry in optical images of disk galaxies is applied to a sample of 32 face-on and nearly face-on spirals. The method involves comparing the relative fluxes contained within trapezoidal sectors arranged symmetrically about the galaxy center of light, excluding the bulge and/or barred regions. Such a method has several advantages over others, especially when quantifying asymmetry in flocculent galaxies. Specifically, the averaging of large regions improves the signal-to-noise in the measurements; the method is not strongly affected by the presence of spiral arms; and it identifies the kinds of asymmetry that are likely to be dynamically important. Application of this "method of sectors" to R-band images of 32 disk galaxies indicates that about 30% of spirals show deviations from axisymmetry at the 5-sigma level.Comment: 17 pages, 2 tables and 6 figures, uses psfig and AAS LaTex; to appear in A

Organic light-emitting diodes as an innovative approach for treating cutaneous leishmaniasis

Funding: UK Engineering and Physical Sciences Research Council (Grant Number(s): EP/L015110/1).Antimicrobial photodynamic therapy (APDT) has been studied as a non-invasive therapy for treating cutaneous leishmaniasis to overcome challenges with current treatment, such as toxicity, resistance and need for in-patient hospital treatment. Organic light-emitting diodes (OLEDs) have emerged as an attractive technology that can provide wearable light-emitting materials that are conformable to human skin. This makes OLEDs ideal candidates for APDT by light-bandages for ambulatory care. In this work, we successfully develop suitable OLEDs to match the absorbance of three photosensitizers: methylene blue, new methylene blue, and 1,9-dimethyl-methylene blue to inactivate two Leishmania species in vitro: Leishmania major and Leishmania amazonensis. Parasites are treated either by LED (20 mWcm-2) or OLED (6.5 mWcm-2) at increasing photosensitizer concentrations at a radiant exposure of 50 Jcm-2. 1,9-Dimethyl-methylene blue is the most potent photosensitizer, killing both strains at nanomolar concentrations. We also explore the effect of different intensities from the OLEDs (0.7, 1.5, and 6.5 mWcm-2) and show that effective killing of Leishmania occurs even at very low intensity. These findings demonstrate the great potential of OLEDs as a new approach for ambulatory treatment of cutaneous leishmaniasis by APDT.Publisher PDFPeer reviewe

Cometary Dust in the Debris Disks of HD 31648 and HD 163296: Two ``Baby'' beta Pics

The debris disks surrounding the pre-main sequence stars HD 31648 and HD 163296 were observed spectroscopically between 3 and 14 microns. Both possess a silicate emission feature at 10 microns which resembles that of the star beta Pictoris and those observed in solar system comets. The structure of the band is consistent with a mixture of olivine and pyroxene material, plus an underlying continuum of unspecified origin. The similarity in both size and structure of the silicate band suggests that the material in these systems had a processing history similar to that in our own solar system prior to the time that the grains were incorporated into comets.Comment: 17 pages, AASTeX, 5 eps figures, accepted for publication in Ap.

Knot Theory: from Fox 3-colorings of links to Yang-Baxter homology and Khovanov homology

This paper is an extended account of my "Introductory Plenary talk at Knots in Hellas 2016" conference We start from the short introduction to Knot Theory from the historical perspective, starting from Heraclas text (the first century AD), mentioning R.Llull (1232-1315), A.Kircher (1602-1680), Leibniz idea of Geometria Situs (1679), and J.B.Listing (student of Gauss) work of 1847. We spend some space on Ralph H. Fox (1913-1973) elementary introduction to diagram colorings (1956). In the second section we describe how Fox work was generalized to distributive colorings (racks and quandles) and eventually in the work of Jones and Turaev to link invariants via Yang-Baxter operators, here the importance of statistical mechanics to topology will be mentioned. Finally we describe recent developments which started with Mikhail Khovanov work on categorification of the Jones polynomial. By analogy to Khovanov homology we build homology of distributive structures (including homology of Fox colorings) and generalize it to homology of Yang-Baxter operators. We speculate, with supporting evidence, on co-cycle invariants of knots coming from Yang-Baxter homology. Here the work of Fenn-Rourke-Sanderson (geometric realization of pre-cubic sets of link diagrams) and Carter-Kamada-Saito (co-cycle invariants of links) will be discussed and expanded. Dedicated to Lou Kauffman for his 70th birthday.Comment: 35 pages, 31 figures, for Knots in Hellas II Proceedings, Springer, part of the series Proceedings in Mathematics & Statistics (PROMS