Semar Makes the Hajj. Shadow Puppet Theatre and Islam in Indonesia

Indonesia, with a population of more than 200 million, of which perhaps 80 percent is Muslim, is frequently portrayed in popular presses as 'the world's largest Islamic nation.' Typically, this statement is then immediately qualified. But, portrayals often continue, 'the' Islam practised by Indonesians is different than that practised in the countries of the Middle and Near East. It is more tempered or syncretic, less dogmatic, doctrinal, or fundamentalist. If proof of this more 'relaxed' attitude to the strict observance of Islam is offered, more often than not it is not through what Indonesian scholars of Islamic law have written (which tends to be rather conservative) nor by attendance figures at Friday mosque services or the number of women who are wearing jilbab head covers (both of which are escalating at remarkable rates). Rather, commentators characteristically turn to the continuing popularity of pre-Islamic cultural forms in contemporary Indonesia Ð Java's celebrated shadow puppet theatre or wayang, with its stories based on the characters and situations of the Indic epics of the Mahabharata and Ramayana, above all

First-principles study of stability and vibrational properties of tetragonal PbTiO_3

A first-principles study of the vibrational modes of PbTiO_3 in the ferroelectric tetragonal phase has been performed at all the main symmetry points of the Brillouin zone (BZ). The calculations use the local-density approximation and ultrasoft pseudopotentials with a plane-wave basis, and reproduce well the available experimental information on the modes at the Gamma point, including the LO-TO splittings. The work was motivated in part by a previously reported transition to an orthorhombic phase at low temperatures [(J. Kobayashi, Y. Uesu, and Y. Sakemi, Phys. Rev. B {\bf 28}, 3866 (1983)]. We show that a linear coupling of orthorhombic strain to one of the modes at Gamma plays a role in the discussion of the possibility of this phase transition. However, no mechanical instabilities (soft modes) are found, either at Gamma or at any of the other high-symmetry points of the BZ.Comment: 8 pages, two-column style with 3 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#ag_pbt

Exploring morphological correlations among H2CO, 12CO, MSX and continuum mappings

There are relatively few H2CO mappings of large-area giant molecular cloud (GMCs). H2CO absorption lines are good tracers for low-temperature molecular clouds towards star formation regions. Thus, the aim of the study was to identify H2CO distributions in ambient molecular clouds. We investigated morphologic relations among 6-cm continuum brightness temperature (CBT) data and H2CO (111-110; Nanshan 25-m radio telescope), 12CO (1--0; 1.2-m CfA telescope) and midcourse space experiment (MSX) data, and considered the impact of background components on foreground clouds. We report simultaneous 6-cm H2CO absorption lines and H110\alpha radio recombination line observations and give several large-area mappings at 4.8 GHz toward W49 (50'\times50'), W3 (70'\times90'), DR21/W75 (60'\times90') and NGC2024/NGC2023 (50'\times100') GMCs. By superimposing H2CO and 12CO contours onto the MSX color map, we can compare correlations. The resolution for H2CO, 12CO and MSX data was about 10', 8' and 18.3", respectively. Comparison of H2CO and 12CO contours, 8.28-\mu m MSX colorscale and CBT data revealed great morphological correlation in the large area, although there are some discrepancies between 12CO and H2CO peaks in small areas. The NGC2024/NGC2023 GMC is a large area of HII regions with a high CBT, but a H2CO cloud to the north is possible against the cosmic microwave background. A statistical diagram shows that 85.21% of H2CO absorption lines are distributed in the intensity range from -1.0 to 0 Jy and the \Delta V range from 1.206 to 5 km/s.Comment: 18 pages, 22 figures, 5 tables. Accepted to be published in Astrophysics and Space Scienc

R-parity preserving super-WIMP decays

We point out that when the decay of one electroweak scale super-WIMP state to another occurs at second order in a super-weak coupling constant, this can naturally lead to decay lifetimes that are much larger than the age of the Universe, and create observable consequences for the indirect detection of dark matter. We demonstrate this in a supersymmetric model with Dirac neutrinos, where the right-handed scalar neutrinos are the lightest and next-to-lightest supersymmetric partners. We show that this model produces a super-WIMP decay rate scaling as m_nu^4/(weak scale)^3, and may significantly enhance the fraction of energetic electrons and positrons over anti-protons in the decay products. Such a signature is consistent with the observations recently reported by the PAMELA experiment.Comment: 14 pages, v3 JHEP versio

Numerical study of chiral symmetry breaking in non-Abelian gauge theory with background magnetic field

We investigate the effect of a uniform background magnetic field on the chiral symmetry breaking in SU(2) Yang-Mills theory on the lattice. We observe that the chiral condensate grows linearly with the field strength B up to \sqrt{e B} = 3 GeV as predicted by chiral perturbation theory for full QCD. As the temperature increases the coefficient in front of the linear term gets smaller. In the magnetic field near-zero eigenmodes of the Dirac operator tend to have more regular structure with larger (compared to zero-field case) Hausdorff dimensionality. We suggest that the delocalization of near-zero eigenmodes plays a crucial role in the enhancement of the chiral symmetry breaking.Comment: 6 pages, Elsevier article style, 5 figures; revision: references and discussions added, published versio

Toy Model for Pion Production II: The role of three-particle singularities

The influence of three-particle breakup singularities on s-wave meson production in nucleon-nucleon collisions is studied within the distorted wave Born approximation. This study is based on a simple scalar model for the two-nucleon interaction and the production mechanism. An algorithm for the exact numerical treatment of the inherent three-body cuts, together with its straightforward implementation is presented. It is also shown that two often-used approximations to avoid the calculation of the three-body breakup are not justified. The possible impact on pion production observables is discussed.Comment: 14 pages, 6 figure

Undetected anomalies in foetuses with a prenatal diagnosis of isolated cleft

The aim of this study was to determine the rate of undetected additional anomalies following a prenatal diagnosis of isolated oral cleft. Data of all infants with a prenatal diagnosis of isolated oral cleft born between 2000 and 2015 were studied retrospectively. Additional anomalies detected after birth were categorized as minor or major and included structural and chromosomal anomalies. Isolated clefts of the lip (CL), lip and alveolus (CLA) and lip, alveolus, and palate (CLAP) were diagnosed prenatally in 176 live-born infants. The type of cleft was more extensive after birth in 34/176 (19.3%) and less extensive in 16/176 (9.1%) newborns. Additional anomalies were diagnosed in 24 infants (13.6%), of which 12 (6.8%) were categorized as major. The latter included two submicroscopic chromosome anomalies and two gene mutations. Postnatal additional anomalies occurred more frequently in CLA and CLAP than in CL, and more in bilateral than in unilateral clefts. Major anomalies are still found in infants with a prenatal diagnosis of an isolated oral cleft. The prevalence of additional anomalies seems to be related to the type and bilaterality of the cleft, and this should be considered during prenatal counselling

Preventing arrhythmic death in patients with tetralogy of Fallot JACC review topic of the week

Patients with tetralogy of Fallot are at risk for ventricular arrhythmias and sudden cardiac death. These abnormalities are associated with pulmonary regurgitation, right ventricular enlargement, and a substrate of discrete, slowly-conducting isthmuses. Although these arrhythmic events are rare, their prediction is challenging. This review will address contemporary risk assessment and prevention strategies. Numerous variables have been proposed to predict who would benefit from an implantable cardioverter-defibrillator. Current risk stratification models combine independently associated factors into risk scores. Cardiac magnetic resonance imaging, QRS fragmentation assessment, and electrophysiology testing in selected patients may refine some of these models. Interaction between right and left ventricular function is emerging as a critical factor in our understanding of disease progression and risk assessment. Multicenter studies evaluating risk factors and risk mitigating strategies such as pulmonary valve replacement, ablative strategies, and use of implantable cardiac-defibrillators are needed moving forward. (c) 2021 by the American College of Cardiology Foundation.Cardiolog

Spin-dephasing anisotropy for electrons in a diffusive quasi-1D GaAs wire

We present a numerical study of dephasing of electron spin ensembles in a diffusive quasi-one-dimensional GaAs wire due to the D'yakonov-Perel' spin-dephasing mechanism. For widths of the wire below the spin precession length and for equal strength of Rashba and linear Dresselhaus spin-orbit fields a strong suppression of spin-dephasing is found. This suppression of spin-dephasing shows a strong dependence on the wire orientation with respect to the crystal lattice. The relevance for realistic cases is evaluated by studying how this effect degrades for deviating strength of Rashba and linear Dresselhaus fields, and with the inclusion of the cubic Dresselhaus term