Broadband quadrature-squeezed vacuum and nonclassical photon number correlations from a nanophotonic device

We report the first demonstrations of both quadrature squeezed vacuum and photon number difference squeezing generated in an integrated nanophotonic device. Squeezed light is generated via strongly driven spontaneous four-wave mixing below threshold in silicon nitride microring resonators. The generated light is characterized with both homodyne detection and direct measurements of photon statistics using photon number-resolving transition edge sensors. We measure $1.0(1)$~dB of broadband quadrature squeezing (${\sim}4$~dB inferred on-chip) and $1.5(3)$~dB of photon number difference squeezing (${\sim}7$~dB inferred on-chip). Nearly-single temporal mode operation is achieved, with raw unheralded second-order correlations $g^{(2)}$ as high as $1.87(1)$ measured (${\sim}1.9$~when corrected for noise). Multi-photon events of over 10 photons are directly detected with rates exceeding any previous quantum optical demonstration using integrated nanophotonics. These results will have an enabling impact on scaling continuous variable quantum technology.Comment: Significant improvements and updates to photon number squeezing results and discussions, including results on single temporal mode operatio

Single pulse sampling valve measurements of wall layer hydrocarbons in a combustion bomb

The processes occurring during head-on flame quench at a cold combustion chamber wall have been studied in a cylindrical combustion bomb. Gas samples were withdrawn from the wall layer using an electrohydraulic sampling valve and were analyzed by gas chromatography. Propane was used as fuel and the experiments were performed at fuel lean ([Phi] = 0.9) conditions. The results indicate that hydrocarbons present in the quench layer are substantially oxidized within 4 ms of flame arrival.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25329/1/0000774.pd

The effects of financialisation and financial development on investment: Evidence from firm-level data in Europe

In this paper we estimate the effects of financialization on physical investment in selected western European countries using panel data based on the balance-sheets of publicly listed non-financial companies (NFCs) supplied by Worldscope for the period 1995-2015. We find robust evidence of an adverse effect of both financial payments (interests and dividends) and financial incomes on investment in fixed assets by the NFCs. This finding is robust for both the pool of all Western European firms and single country estimations. The negative impacts of financial incomes are non-linear with respect to the companies’ size: financial incomes crowd-out investment in large companies, and have a positive effect on the investment of only small, relatively more credit-constrained companies. Moreover, we find that a higher degree of financial development is associated with a stronger negative effect of financial incomes on companies’ investment. This finding challenges the common wisdom on ‘finance-growth nexus’. Our findings support the ‘financialization thesis’ that the increasing orientation of the non-financial sector towards financial activities is ultimately leading to lower physical investment, hence to stagnant or fragile growth, as well as long term stagnation in productivity

Neonatal Pain-Related Stress and NFKBIA Genotype Are Associated with Altered Cortisol Levels in Preterm Boys at School Age

Neonatal pain-related stress is associated with elevated salivary cortisol levels to age 18 months in children born very preterm, compared to full-term, suggesting early programming effects. Importantly, interactions between immune/inflammatory and neuroendocrine systems may underlie programming effects. We examined whether cortisol changes persist to school age, and if common genetic variants in the promoter region of the NFKBIA gene involved in regulation of immune and inflammatory responses, modify the association between early experience and later life stress as indexed by hair cortisol levels, which provide an integrated index of endogenous HPA axis activity. Cortisol was assayed in hair samples from 128 children (83 born preterm ≤ 32 weeks gestation and 45 born full-term) without major sensory, motor or cognitive impairments at age 7 years. We found that hair cortisol levels were lower in preterm compared to term-born children. Downregulation of the HPA axis in preterm children without major impairment, seen years after neonatal stress terminated, suggests persistent alteration of stress system programming. Importantly, the etiology was gender-specific such that in preterm boys but not girls, specifically those with the minor allele for NFKBIA rs2233409, lower hair cortisol was associated with greater neonatal pain (number of skin-breaking procedures from birth to term), independent of medical confounders. Moreover, the minor allele (CT or TT) of NFKBIA rs2233409 was associated with higher secretion of inflammatory cytokines, supporting the hypothesis that neonatal pain-related stress may act as a proinflammatory stimulus that induces long-term immune cell activation. These findings are the first evidence that a long-term association between early pain-related stress and cortisol may be mediated by a genetic variants that regulate the activity of NF-κB, suggesting possible involvement of stress/inflammatory mechanisms in HPA programming in boys born very preterm

Spectral compression of single photons

Photons are critical to quantum technologies since they can be used for virtually all quantum information tasks: in quantum metrology, as the information carrier in photonic quantum computation, as a mediator in hybrid systems, and to establish long distance networks. The physical characteristics of photons in these applications differ drastically; spectral bandwidths span 12 orders of magnitude from 50 THz for quantum-optical coherence tomography to 50 Hz for certain quantum memories. Combining these technologies requires coherent interfaces that reversibly map centre frequencies and bandwidths of photons to avoid excessive loss. Here we demonstrate bandwidth compression of single photons by a factor 40 and tunability over a range 70 times that bandwidth via sum-frequency generation with chirped laser pulses. This constitutes a time-to-frequency interface for light capable of converting time-bin to colour entanglement and enables ultrafast timing measurements. It is a step toward arbitrary waveform generation for single and entangled photons.Comment: 6 pages (4 figures) + 6 pages (3 figures

Equine asthma: current understanding and future directions

The 2019 Havemeyer Workshop brought together researchers and clinicians to discuss the latest information on Equine Asthma and provide future research directions. Current clinical and molecular asthma phenotypes and endotypes in humans were discussed and compared to asthma phenotypes in horses. The role of infectious and non-infectious causes of equine asthma, genetic factors and proposed disease pathophysiology were reviewed. Diagnostic limitations were evident by the limited number of tests and biomarkers available to field practitioners. The participants emphasized the need for more accessible, standardized diagnostics that would help identify specific phenotypes and endotypes in order to create more targeted treatments or management strategies. One important outcome of the workshop was the creation of the Equine Asthma Group that will facilitate communication between veterinary practice and research communities through published and easily accessible guidelines and foster research collaboration

SPIN90 associates with mDia1 and the Arp2/3 complex to regulate cortical actin organization

Cell shape is controlled by the submembranous cortex, an actomyosin network mainly generated by two actin nucleators: the Arp2/3 complex and the formin mDia1. Changes in relative nucleator activity may alter cortical organization, mechanics and cell shape. Here we investigate how nucleation-promoting factors mediate interactions between nucleators. In vitro, the nucleation-promoting factor SPIN90 promotes formation of unbranched filaments by Arp2/3, a process thought to provide the initial filament for generation of dendritic networks. Paradoxically, in cells, SPIN90 appears to favour a formin-dominated cortex. Our in vitro experiments reveal that this feature stems mainly from two mechanisms: efficient recruitment of mDia1 to SPIN90-Arp2/3 nucleated filaments and formation of a ternary SPIN90-Arp2/3-mDia1 complex that greatly enhances filament nucleation. Both mechanisms yield rapidly elongating filaments with mDia1 at their barbed ends and SPIN90-Arp2/3 at their pointed ends. Thus, in networks, SPIN90 lowers branching densities and increases the proportion of long filaments elongated by mDia1

Individual-level socioeconomic status is associated with worse asthma morbidity in patients with asthma

<p>Abstract</p> <p>Background</p> <p>Low socioeconomic status (SES) has been linked to higher morbidity in patients with chronic diseases, but may be particularly relevant to asthma, as asthmatics of lower SES may have higher exposures to indoor (e.g., cockroaches, tobacco smoke) and outdoor (e.g., urban pollution) allergens, thus increasing risk for exacerbations.</p> <p>Methods</p> <p>This study assessed associations between adult SES (measured according to educational level) and asthma morbidity, including asthma control; asthma-related emergency health service use; asthma self-efficacy, and asthma-related quality of life, in a Canadian cohort of 781 adult asthmatics. All patients underwent a sociodemographic and medical history interview and pulmonary function testing on the day of their asthma clinic visit, and completed a battery of questionnaires (Asthma Control Questionnaire, Asthma Quality of Life Questionnaire, and Asthma Self-Efficacy Scale). General Linear Models assessed associations between SES and each morbidity measure.</p> <p>Results</p> <p>Lower SES was associated with worse asthma control (F = 11.63, p < .001), greater emergency health service use (F = 5.09, p = .024), and worse asthma self-efficacy (F = 12.04, p < .01), independent of covariates. Logistic regression analyses revealed that patients with <12 years of education were 55% more likely to report an asthma-related emergency health service visit in the last year (OR = 1.55, 95%CI = 1.05-2.27). Lower SES was not related to worse asthma-related quality of life.</p> <p>Conclusions</p> <p>Results suggest that lower SES (measured according to education level), is associated with several indices of worse asthma morbidity, particularly worse asthma control, in adult asthmatics independent of disease severity. Results are consistent with previous studies linking lower SES to worse asthma in children, and add asthma to the list of chronic diseases affected by individual-level SES.</p