Compressive Raman imaging with spatial frequency modulated illumination

We report a line scanning imaging modality of compressive Raman technology with spatial frequency modulated illumination using a single pixel detector. We demonstrate the imaging and classification of three different chemical species at line scan rates of 40 Hz

Super resolution computational saturated absorption microscopy

Imaging beyond the diffraction limit barrier has attracted wide attention due to the ability to resolve image features that were previously hidden. Of the various super-resolution microscopy techniques available, a particularly simple method called saturated excitation microscopy (SAX) requires only a simple modification of a laser scanning microscope where the illumination beam power is sinusoidally modulated and driven into saturation. SAX images are extracted from harmonics of the modulation frequency and exhibit improved spatial resolution. Unfortunately, this elegant strategy is hindered by the incursion of shot noise that prevents high resolution imaging in many realistic scenarios. Here, we demonstrate a new technique for super resolution imaging that we call computational saturated absorption (CSA) in which a joint deconvolution is applied to a set of images with diversity in spatial frequency support among the point spread functions used in the image formation with saturated laser scanning fluorescence microscope. CSA microscopy allows access to the high spatial frequency diversity in a set of saturated effective point spread functions, while avoiding image degradation from shot noise.Comment: 26 pages, 15 figure

Extended X-Ray Emission from QSOs

We report Chandra ACIS observations of the fields of 4 QSOs showing strong extended optical emission-line regions. Two of these show no evidence for significant extended X-ray emission. The remaining two fields, those of 3C 249.1 and 4C 37.43, show discrete (but resolved) X-ray sources at distances ranging from ~10 to ~40 kpc from the nucleus. In addition, 4C 37.43 also may show a region of diffuse X-ray emission extending out to ~65 kpc and centered on the QSO. It has been suggested that extended emission-line regions such as these may originate in the cooling of a hot intragroup medium. We do not detect a general extended medium in any of our fields, and the upper limits we can place on its presence indicate cooling times of at least a few 10^9 years. The discrete X-ray emission sources we detect cannot be explained as the X-ray jets frequently seen associated with radio-loud quasars, nor can they be due to electron scattering of nuclear emission. The most plausible explanation is that they result from high-speed shocks from galactic superwinds resulting either from a starburst in the QSO host galaxy or from the activation of the QSO itself. Evidence from densities and velocities found from studies of the extended optical emission around QSOs also supports this interpretation.Comment: Accepted by ApJ. 9 pages including 5 figure

Extending the Information Revolution

America has a grand opportunity to lay the foundations for a prosperous and secure future. Our task is not just reviving the weak economy or increasing security -- as important as those are. Real sustainable economic growth and international security will come from expanding the information revolution to all parts of our society. Metcalfe's Law states that the value of a network increases exponentially in relation to the number of users. The same is true for markets and economic activity. By leaving some behind -- both at home and around the world, we impoverish not only those individuals; we also impoverish ourselves. This paper lays out a series of recommendations in a number of areas from a number of experts. It is based on some shared principles:the critical importance of inclusion and true participation by all;technology is, and should be, a tool -- the means to an end, not the end itself;open and competitive economic systems work best;and a more economically prosperous world is a more secure world

Trust, guilds and kinship in London, 1330-1680

How was trust created and reinforced between the inhabitants of medieval and early modern cities? And how did the social foundations of trusting relationships change over time? Current research highlights the role of kinship, neighbourhood and associations, particularly guilds, in creating ‘relationships of trust’ and social capital in the face of high levels of migration, mortality and economic volatility, but tells us little about their relative importance or how they developed. We uncover a profound shift in the contribution of family and guilds to trust networks among the middling and elite of one of Europe’s major cities, London, over three centuries, from the 1330s to the 1680s. We examine the networks of sureties created to secure the inheritances of children whose fathers died while they were minors, surviving in the records of London’s Orphans Court. Our analysis of almost fifteen thousand networks evaluates the presence of trusting relationships connected with guild membership, family and place over several centuries. We show a profound increase in the role of kinship – a re-embedding of trust within the family - and a decline of the importance of shared guild membership in connecting Londoner’s who secured orphans’ inheritances together. We suggest these developments are best explained as a result of the impact of the Reformation on the form and intensity of sociability fostered by guilds and the enormous growth of the metropolis

Red Nuggets at z~1.5: Compact passive galaxies and the formation of the Kormendy Relation

We present the results of NICMOS imaging of a sample of 16 high mass passively evolving galaxies with 1.3<z<2, taken primarily from the Gemini Deep Deep Survey. Around 80% of galaxies in our sample have spectra dominated by stars with ages >1 Gyr. Our rest-frame R-band images show that most of these objects have compact regular morphologies which follow the classical R^1/4 law. These galaxies scatter along a tight sequence in the Kormendy relation. Around one-third of the massive red objects are extraordinarily compact, with effective radii under one kiloparsec. Our NICMOS observations allow the detection of such systems more robustly than is possible with optical (rest-frame UV) data, and while similar systems have been seen at z>2, this is the first time such systems have been detected in a rest-frame optical survey at 1.3<z<2. We refer to these compact galaxies as "red nuggets". Similarly compact massive galaxies are completely absent in the nearby Universe. We introduce a new "stellar mass Kormendy relation" (stellar mass density vs size) which isolates the effects of size evolution from those of luminosity and color evolution. The 1.1 < z < 2 passive galaxies have mass densities that are an order of magnitude larger then early type galaxies today and are comparable to the compact distant red galaxies at 2 < z < 3. We briefly consider mechanisms for size evolution in contemporary models focusing on equal-mass mergers and adiabatic expansion driven by stellar mass loss. Neither of these mechanisms appears able to transform the high-redshift Kormendy relation into its local counterpart. Comment: Accepted version (to appear in ApJ

Nipah Virus Infection in Dogs, Malaysia, 1999

The 1999 outbreak of Nipah virus encephalitis in humans and pigs in Peninsular Malaysia ended with the evacuation of humans and culling of pigs in the epidemic area. Serologic screening showed that, in the absence of infected pigs, dogs were not a secondary reservoir for Nipah virus

Bat Nipah Virus, Thailand

Surveillance for Nipah virus (NV) was conducted in Thailand's bat population. Immunoglobulin G antibodies to NV were detected with enzyme immunoassay in 82 of 1,304 bats. NV RNA was found in bat saliva and urine. These data suggest the persistence of NV infection in Thai bats