2,743 research outputs found
The Sacred Geography of Dawei: Buddhism in peninsular Myanmar (Burma)
The paper opens by recounting the beginnings of Buddhism in Dawei as preserved in local chronicles and sustained in stupas marking the episodes of the chronicle narrative. The chronicles start with a visit of the Buddha whose arrival triggers a series of events bringing together pre-existing tutelary figures, weiza, a hermit and offspring born of a golden fish, culminating in the establishment of the first Buddhist kingdom circa the eighth to tenth century CE. The enshrinement of sacred hairs gifted by the Buddha also includes patronage by a king of the ‘Suvannbhumi’ lineage. Associated with the monks Sona and Uttara from Sri Lanka sent by King Asoka’s son Mahinda, ‘Suvannbhumi’ literally can refer to the archaeology of Thaton, a walled site in the present day Mon State, or, as is the case here, more widely to the missionary tradition associated with Asoka (Sao Saimong Mengrai 1976). The third story in the establishment of the Buddhist king at Thagara is the longest of the chronicle, the tale of a royal hunter who failed to capture a golden peacock for the queen. The hunter became a hermit living by a pond with a golden fish and as he urinated in the pond, two children were born from the fish. The boy becomes the first Buddhist king of Thagara, 11 km north of Dawei, where artefacts from survey and excavation confirm the chronology of the chronicle, with the closest archaeological parallels found not at the ancient sites of the Mon State but to the first millennium CE Buddhist ‘Pyu’ heritage of Upper Myanmar which is notably absent in the chronicle compilation
Electrostatically Tunable Meta-Atoms Integrated With In Situ Fabricated MEMS Cantilever Beam Arrays
Two concentric split ring resonators (SRRs) or meta-atoms designed to have a resonant frequency of 14 GHz are integrated with microelectromechanical systems cantilever arrays to enable electrostatic tuning of the resonant frequency. The entire structure was fabricated monolithically to improve scalability and minimize losses from externally wire-bonded components. A cantilever array was fabricated in the gap of both the inner and outer SRRs and consisted of five evenly spaced beams with lengths ranging from 300 to 400 μm. The cantilevers pulled in between 15 and 24 V depending on the beam geometry. Each pulled-in beam increased the SRR gap capacitance resulting in an overall 1-GHz shift of the measured meta-atom resonant frequency
The infrared imaging spectrograph (IRIS) for TMT: sensitivities and simulations
We present sensitivity estimates for point and resolved astronomical sources
for the current design of the InfraRed Imaging Spectrograph (IRIS) on the
future Thirty Meter Telescope (TMT). IRIS, with TMT's adaptive optics system,
will achieve unprecedented point source sensitivities in the near-infrared
(0.84 - 2.45 {\mu}m) when compared to systems on current 8-10m ground based
telescopes. The IRIS imager, in 5 hours of total integration, will be able to
perform a few percent photometry on 26 - 29 magnitude (AB) point sources in the
near-infrared broadband filters (Z, Y, J, H, K). The integral field
spectrograph, with a range of scales and filters, will achieve good
signal-to-noise on 22 - 26 magnitude (AB) point sources with a spectral
resolution of R=4,000 in 5 hours of total integration time. We also present
simulated 3D IRIS data of resolved high-redshift star forming galaxies (1 < z <
5), illustrating the extraordinary potential of this instrument to probe the
dynamics, assembly, and chemical abundances of galaxies in the early universe.
With its finest spatial scales, IRIS will be able to study luminous, massive,
high-redshift star forming galaxies (star formation rates ~ 10 - 100 M yr-1) at
~100 pc resolution. Utilizing the coarsest spatial scales, IRIS will be able to
observe fainter, less massive high-redshift galaxies, with integrated star
formation rates less than 1 M yr-1, yielding a factor of 3 to 10 gain in
sensitivity compared to current integral field spectrographs. The combination
of both fine and coarse spatial scales with the diffraction-limit of the TMT
will significantly advance our understanding of early galaxy formation
processes and their subsequent evolution into presentday galaxies.Comment: SPIE Astronomical Instrumentation 201
A Novel Item-Allocation Procedure for the Three-Form Planned Missing Data Design
We propose a new method of constructing questionnaire forms in the three-form planned missing data design (PMDD). The random item allocation (RIA) procedure that we propose promises to dramatically simplify the process of implementing three-form PMDDs without compromising statistical performance. Our method is a stochastic approximation to the currently recommended approach of deterministically spreading a scale\u27s items across the X-, A-, B-, and C-blocks when allocating the items in a three-form design. Direct empirical support for the performance of our method is only available for scales containing at least 12 items, so we also propose a modified approach for use with scales containing fewer than 12 items. We also discuss the limitations of our procedure and several nuances for researchers to consider when implementing three-form PMDDs using our method. The RIA procedure allows researchers to implement statistically sound three-form planned missing data designs without the need for expert knowledge or results from prior statistical modeling. The RIA procedure can be used to construct both “paper-and-pencil” questionnaires and questionnaires administered through online survey software. The RIA procedure is a simple framework to aid in designing three-form PMDDs; implementing the RIA method does not require any specialized software or technical expertise
Criticality of two-dimensional disordered Dirac fermions in the unitary class and universality of the integer quantum Hall transition
Two-dimensional (2D) Dirac fermions are a central paradigm of modern
condensed matter physics, describing low-energy excitations in graphene, in
certain classes of superconductors, and on surfaces of 3D topological
insulators. At zero energy E=0, Dirac fermions with mass m are band insulators,
with the Chern number jumping by unity at m=0. This observation lead Ludwig et
al [Phys. Rev. B 50, 7526 (1994)] to conjecture that the transition in 2D
disordered Dirac fermions (DDF) and the integer quantum Hall transition (IQHT)
are controlled by the same fixed point and possess the same universal critical
properties. Given the far-reaching implications for the emerging field of the
quantum anomalous Hall effect, modern condensed matter physics and our general
understanding of disordered critical points, it is surprising that this
conjecture has never been tested numerically. Here, we report the results of
extensive numerics on the phase diagram and criticality of 2D-DDF in the
unitary class. We find a critical line at m=0, with energy-dependent
localization length exponent. At large energies, our results for the DDF are
consistent with state-of-the-art numerical results \nu_IQH = 2.56 - 2.62 from
models of the IQHT. At E=0 however, we obtain \nu_0 =2.30-2.36 incompatible
with \nu_IQH. This result challenges conjectured relations between different
models of the IQHT, and several interpretations are discussed.Comment: close to published versio
Academic Libraries on Social Media: Finding the Students and the Information They Want
Librarians from Purdue University wanted to determine which social media platforms students use, which platforms they would like the library to use, and what content they would like to see from the library on each of these platforms. We conducted a survey at four of the nine campus libraries to determine student social media habits and preferences. Results show that students currently use Facebook, YouTube, and Snapchat more than other social media types; however, students responded that they would like to see the library on Facebook, Instagram, and Twitter. Students wanted nearly all types of content from the libraries on Facebook, Twitter, and Instagram, but they did not want to receive business news or content related to library resources on Snapchat. YouTube was seen as a resource for library service information. We intend to use this information to develop improved communication channels, a clear libraries social media presence, and a cohesive message from all campus libraries
The infrared imaging spectrograph (IRIS) for TMT: spectrograph design
The Infra-Red Imaging Spectrograph (IRIS) is one of the three first light
instruments for the Thirty Meter Telescope (TMT) and is the only one to
directly sample the diffraction limit. The instrument consists of a parallel
imager and off-axis Integral Field Spectrograph (IFS) for optimum use of the
near infrared (0.84um-2.4um) Adaptive Optics corrected focal surface. We
present an overview of the IRIS spectrograph that is designed to probe a range
of scientific targets from the dynamics and morphology of high-z galaxies to
studying the atmospheres and surfaces of solar system objects, the latter
requiring a narrow field and high Strehl performance. The IRIS spectrograph is
a hybrid system consisting of two state of the art IFS technologies providing
four plate scales (4mas, 9mas, 25mas, 50mas spaxel sizes). We present the
design of the unique hybrid system that combines the power of a lenslet
spectrograph and image slicer spectrograph in a configuration where major
hardware is shared. The result is a powerful yet economical solution to what
would otherwise require two separate 30m-class instruments.Comment: 15 pages, 11 figure
Prospects for measuring supermassive black hole masses with future extremely large telescopes
The next generation of giant-segmented mirror telescopes ( 20 m) will
enable us to observe galactic nuclei at much higher angular resolution and
sensitivity than ever before. These capabilities will introduce a revolutionary
shift in our understanding of the origin and evolution of supermassive black
holes by enabling more precise black hole mass measurements in a mass range
that is unreachable today. We present simulations and predictions of the
observations of nuclei that will be made with the Thirty Meter Telescope (TMT)
and the adaptive optics assisted integral-field spectrograph IRIS, which is
capable of diffraction-limited spectroscopy from band (0.9 m) to
band (2.2 m). These simulations, for the first time, use realistic values
for the sky, telescope, adaptive optics system, and instrument, to determine
the expected signal-to-noise ratio of a range of possible targets spanning
intermediate mass black holes of \msun to the most massive black
holes known today of . We find that IRIS will be able to
observe Milky Way-mass black holes out the distance of the Virgo cluster, and
will allow us to observe many more brightest cluster galaxies where the most
massive black holes are thought to reside. We also evaluate how well the
kinematic moments of the velocity distributions can be constrained at the
different spectral resolutions and plate scales designed for IRIS. We find that
a spectral resolution of will be necessary to measure the masses of
intermediate mass black holes. By simulating the observations of galaxies found
in SDSS DR7, we find that over massive black holes will be observable at
distances between with the estimated sensitivity and angular
resolution provided by access to -band (0.9 m) spectroscopy from IRIS
and the TMT adaptive optics system. (Abridged)Comment: 19 pages, 20 figures, accepted to A
Transcriptomes of parents identify parenting strategies and sexual conflict in a subsocial beetle
This work was funded by UK NERC grants to M.G.R. and A.J.M. an NERC studentship to D.J.P. the University of Georgia and a US NSF grant to A.J.M. and M.G.R.Parenting in the burying beetle Nicrophorus vespilloides is complex and, unusually, the sex and number of parents that can be present is flexible. Such flexibility is expected to involve specialized behaviour by the two sexes under biparental conditions. Here, we show that offspring fare equally well regardless of the sex or number of parents present. Comparing transcriptomes, we find a largely overlapping set of differentially expressed genes in both uniparental and biparental females and in uniparental males including vitellogenin, associated with reproduction, and takeout, influencing sex-specific mating and feeding behaviour. Gene expression in biparental males is similar to that in non-caring states. Thus, being ‘biparental’ in N. vespilloides describes the family social organization rather than the number of directly parenting individuals. There was no specialization; instead, in biparental families, direct male parental care appears to be limited with female behaviour unchanged. This should lead to strong sexual conflict.Publisher PDFPeer reviewe
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