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The ability to manipulate and measure the time-frequency structure of quantum light is useful for information processing and metrology. Measuring this structure is also important when developing quantum light sources with high modal purity that can interfere with other independent sources. Here, we present and experimentally demonstrate a scheme based on intensity interferometry to measure the joint spectral mode of photon pairs produced by spontaneous parametric down-conversion. We observe correlations in the spectral phase of the photons due to chirp in the pump. We show that our scheme can be combined with stimulated emission tomography to quickly measure their mode using bright classical light. Our scheme does not require phase stability, nonlinearities, or spectral shaping, and thus is an experimentally simple way of measuring the modal structure of quantum light., Comment: 8 pages, 6 figures; includes Supplemental Material

For more than 30 years, institutions funded by NIH had less than an impressive record for achieving diversity in the bio- medical workforce. To address this concern, NIH recently implemented a series of bold initiatives to bridge the gaps in NIH training programs to further promote diversity. However, critical to the success of these initiatives is the timely report- ing, from institutions with large diverse populations such as HBCUs, of evidence-based practices, strategies, and interven- tions for training and transitioning individuals underrepre- sented (UR) in the biomedical sciences from baccalaureate to Ph.D. degree programs. To this end, the purpose of this study is to evaluate the 10-year success of the NIH-funded MBRS Fayetteville State University (FSU) Research Initiative for Scientific Enhancement (FSU-RISE) program for training and subsequent transitioning of UR students from the baccalaure- ate degree into advanced degree programs in the biomedical sciences. We hypothesized that the FSU-RISE program would significantly increase the number of well-prepared under- graduate UR biology and chemistry students who would graduate and transition into advanced degree programs in the biomedical sciences. This article provides evidence-based findings on practices, strategies and interventions for prepar- ing UR individuals from a Historically Black College and Uni- versity (HBCU) for successful entry into Ph.D. programs

In this work, we investigate the properties of four-wave mixing Bragg scattering in a configuration that employs orthogonally polarized pumps in a birefringent waveguide. This configuration enables a large signal conversion bandwidth, and allows strongly unidirectional frequency conversion as undesired Bragg-scattering processes are suppressed by waveguide birefringence. Moreover, we show that this form of four-wave mixing Bragg scattering preserves the (arbitrary) signal pulse shape, even when driven by pulsed pumps., 11 pages + refs, 5 figures

To further develop the programme theory, three geographically discrete areas were identified with models of health care emphasising respectively: expertise in care of older adults organised around the care home; incentive-driven care using general practitioners (GPs) as co-ordinators; and mixed provision typical of usual UK care delivery. 242 residents from 12 care homes had baseline health status described using the InterRAI-LTC and their healthcare resource use and associated costs over 12 months collated. Interviews and focus groups with 181 health and social care professionals, residents and families described the care received. Healthcare costs per resident were greatest where provision was ad hoc and mixed. GP contacts and costs were greater where incentives emphasised GP contact. The most positive accounts were of models which recognised the pivotal role of homes in healthcare delivery, supported effective relational working between health and social care staff and allowed GPs to focus on medical care.

We introduce the concept of entanglement enhanced interferometry from the viewpoint of the detected photons. The standard quantum limit is achieved when sequentially detected photons are assumed to be in an uncorrelated product state. However when we access the correlations between the detected photons that existed before the interferometer it becomes clear that entanglement enhanced measurement beyond the quantum limit could be achieved independent of loss. We describe possible realisations of this post-measurement entanglement detection using a small array of spin photon entangling gates. We then describe a proof of principle experiment using only linear optics resources., Comment: This paper has been withdrawn by the authors due to some crucial errors

A computerized system has been developed which potentially enables a single expert physician to monitor a large number of hypertensive patients being seen at distant locations. The patients may receive their care directly from primary care physicians or nurse-physician surrogates. Primary care physicians can use the same data bank to monitor their own panels of patients. These goals are accomplished through a special purpose, interactive programming language which can be used to perform sophisticated data retrieval along different complexes of parameters. The physician is able to query the computer, via a terminal, about any group of patient he defines and have displayed to him the clinical data requested. The system is open-ended, enabling one query to lead to another. Four hundred and ninety-three patients have been entered into this program so far, including 29 patients with diastolic pressures greater than 115, 92 with diastolic pressures of 104 to 114, and 372 with diastolics of 90 to 104. Among patients who have been on therapy for at least six weeks, 80 per cent were at goal blood pressure. Ten to 14 weeks after therapy was initiated, 69 per cent of all patients in the program were at goal blood pressure. The system provides a useful means of monitoring a large hypertensive population of patients. Such a system can result in a more efficient utilization of medical personnel and can bring the consultative services of highly trained specialists to larger segments of the population.

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This paper examines alternative approaches to wage subsidy programmes. It does this in the context of a recent active labour market reform for the young unemployed in Britain. This ?ew Deal?reform and the characteristics of the target group are examined in detail. We discuss theoretical considerations, survey the existing empirical evidence and propose two strategies for evaluation. The first suggests an expost ?rend adjusted dihrence in dihrence' estimator. The second, relates to a model based ex-ante evaluation. We present the conditions for each to provide a reliable evaluation and W some of the crucial parameters using data from the British Labour Force Survey. We stress that the success of this type of labour market programmes hinge on dynamic aspects of the youth labour market, in particular the pay-off to experience and training.

This thesis consists of three independent chapters. The first two chapters are motivated by an empirical fact: most countries in Latin America experienced sharp changes in the wage structure since the mid-1990s, characterised by a substantial reduction of earnings inequality. At the same time that inequality was falling, the economies in the region experienced a rapid transformation of the age, education, and gender composition of their workforces. To what extent are these two phenomena interconnected? Did the wage structure changed as a consequence of the recomposition of labor supply? To answer these questions I propose two stylized models of the labor market, and estimate their main parameters using household survey data ranging more than two decades from Argentina, Brazil, Chile and Mexico. I provide evidence that supply side trends are the major driver of the observed patterns in relative earnings. While relative demands favoured high-skilled workers during the 1990s, they shifted in favour of low-skilled workers during the 2000s. In the third chapter the subject matter changes altogether. Here I will focus on the workings of newly developed financial technologies used by entrepreneurs to raise capital for their businesses. In particular, the rapidly growing equity crowdfunding market is analysed. The chapter is motivated by the concerns of analysts and regulators that crowdfunding markets are vulnerable to investment herding, so that prior investors' decisions induce future investors to make similar choices. We develop a stylised model to answer the following question: how should herding be characterised in an equity crowdfunding setting where much of the inter-temporal information about a project is based on the amounts previously invested? The model generates predictions that we test using a unique investment-level dataset from one of the leading UK equity crowdfunding platforms. We provide evidence of a considerable level of immediate inter-temporal herding on an equity crowdfunding platform that, nevertheless, quickly dissipates.

MicroStrip Gas Chambers (MSGC's) have been proposed for equipping the outer region of the tracker of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). The MSGC's have undergone extensive development and tests during the last few years and their performance is well established. An important issue that has to be addressed to date is whether MSGC's can maintain their characteristics after a long exposure to an intense flux of particles, similar to LHC. We report results from the most recent beam test addressing this topic.