On Quasar Masses and Quasar Host Galaxies

The mass of massive black holes in quasar cores can be deduced using the typical velocities of Hb-emitting clouds in the Broad Line Region (BLR) and the size of this region. However, this estimate depends on various assumptions and is susceptible to large systematic errors. The Hb-deduced black hole mass in a sample of 14 bright quasars is found here to correlate with the quasar host galaxy luminosity, as determined with the Hubble Space Telescope (HST). This correlation is similar to the black hole mass vs. bulge luminosity correlation found by Magorrian et al. in a sample of 32 nearby normal galaxies. The similarity of the two correlations is remarkable since the two samples involve apparently different types of objects and since the black hole mass estimates in quasars and in nearby galaxies are based on very different methods. This similarity provides a ``calibration'' of the Hb-deduced black hole mass estimate, suggesting it is accurate to +-0.5 on log scale. The similarity of the two correlations also suggests that quasars reside in otherwise normal galaxies, and that the luminosity of quasar hosts can be estimated to +-0.5 mag based on the quasar continuum luminosity and the Hb line width. Future imaging observations of additional broad-line active galaxies with the HST are required in order to explore the extent, slope, and scatter of the black hole mass vs. host bulge luminosity correlation in active galaxies.Comment: Accepted for publication in ApJ Letters, 7 pages, aas2pp4.st

Studi Kinetika Adsorpsi Pb Menggunakan Arang Aktif Dari Kulit Pisang

- Lead metal is one of environment polluter and can cause decease or health problems in sort time. The way to solve this problem is with used the carbon active from banana peel. This research is intend to find the kinetics model that appropriate in Pb adsorption process by knowing absorption of banana peel carbon active within mass variations (1; 1,5 and 2 g) and contact time (20, 40, and 60 minutes). Kinetics analysis are based from orde zero,one, and two and find the maximum capacity of adsorption from banana peel carbon active to lead metal. Equation which using at the adsorption process are Langmuir and Freundlich isotherm equations. From the analysis results, optimum time is at 60 minutes.kinetics of Pb absorption with carbon active from banana peel in mass 1 and 2 gr following kinetics model orde 2, then in mass 1,5 g following kinetics model orde 0. Langmuir equation is more appropriate in this research. Pb absorption from the banana peel that appropriate to Langmuir isotherm system is indicates adsorption was occur in one layer (monolayer). Maximum adsorption capacity is showing by the bigger value from a, that is 1,4582 in mass 1 g then interaction power of Pb with the banana peel was occur in mass 2 gr which showing with the value of kL is 0,4090

The Relationship Between Smartphone Addiction and Forward Head Posture in Junior High School Students in North Denpasar

Background:Nowadays, the smartphone has become an important requirement. The number of smartphone users and the duration of smartphone use is increasing rapidly, and the side effects can be detrimental one of them is forward head posture. The prevalence of forward head posture is greater women (24.1%) than men (9.1%).Methods:This study was an analytical observational study with a cross-sectional design.This research was conducted in April 2019 in SMP Negeri 2 Denpasar and SMP Negeri 4 Denpasar andincluding 56 samples, who were recruited through simple random sampling.Variables studied are smartphone addition was measured using the Smartphone Addiction Scale questionnaire, and forward head posture was measured by measuring craniovertebral angles. Data analysis was done using the Chi-Square test. Result: Based on this study, smartphone addiction was related to forward head posture. The research shows that as many as 45 samples had Smartphone Addiction (80.35%) while those who had forward head posture were 29 samples (51.78%).Conclusion : Ignorance of how to sort and choose the effects of globalization, especially smartphone use, which can lead to posture disorders. The factor recognized factors for the occurrences of the forward head posture the lack of education about ergonomic positions when using a smartphone. Parents are advised to set the right smartphone usage for children as early as possible

Shocks near Jamming

Non-linear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they jam, these fragile and disordered solids exhibit a vanishing rigidity and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are dynamically compressed, and demonstrate that the elementary excitations are strongly non-linear shocks, rather than ordinary phonons. We capture the full dependence of the shock speed on pressure and impact intensity by a surprisingly simple analytical model.Comment: Revised version. Accepted for publication in Phys. Rev. Let

Electromagnetic wave refraction at an interface of a double wire medium

Plane-wave reflection and refraction at an interface with a double wire medium is considered. The problem of additional boundary conditions (ABC) in application to wire media is discussed and an ABC-free approach, known in the solid state physics, is used. Expressions for the fields and Poynting vectors of the refracted waves are derived. Directions and values of the power density flow of the refracted waves are found and the conservation of the power flow through the interface is checked. The difference between the results, given by the conventional model of wire media and the model, properly taking into account spatial dispersion, is discussed.Comment: 17 pages, 11 figure

Identification Of Antibacterial Compounds Isolated From Leucaena Leucocephala (Lam.) De Wit.) Leaves

Plants are important natural resources widely explored for maintaining health and treatment of diseases. One of them is Leucaena leucocephala leaf which is used as traditional medicine. Indonesian has used this leaf to treat wound and inflammation. This study was conducted to isolate and identify antibacterial compounds from L. leucocephala leaves. Dry powder of this leaf was extracted using washbenzen by Soxhletation method followed by methanol extraction. Both extracts were tested for antibacterial activity against Staphylococcus aureus ATCC 25923 dan E. coli 25922 and analysed by TLC. Positive extract to S. aureus was further separated by vacuum liquid chromatography using different combination of washbenzene and ethyl acetate followed by analysis using TLC. Each fraction was tested for antibacterial activity and analysed by TLC. The positive fraction was further separated by TLC-preparative, assigned as p1a, p2a, p3a. The active compound (p2a) was tested for its purity using TLC with various mobile phase. Its structure was identified using combination data of UV-Vis and IR spectrophotometry, GC-MS and NMR. Based on UV-Vis data, this compound showed the absence of chromophoric group. IR data showed adsorption at 3409,4 cm-1 (OH), 2928,2 cm-1(CHaliphatic), 2854,3 cm-1(CHaliphatic), 1575,5 cm-1 (C=C), 1416,4 cm-1 (CH2), 1385,0 cm-1(CH3), 1258,3 cm-1 and 1082,3 cm-1 (C-O). GC-MS data showed molecule ion at m/z 482 (M + H+)and fragmented ion at m/z 427 (M + H+). 1H-NMR (CDCl3) spectrum showed resonance at δ 0,8; 1,4; 1,6; 2,0; 2,3; 3,6; 4,2 and 5,4 pp, suggesting that this compound is lupeol