Exceptional-point-assisted entanglement, squeezing, and reset in a chain of three superconducting resonators

The interplay between coherent and dissipative dynamics required in various control protocols of quantum technology has motivated studies of open-system degeneracies, referred to as exceptional points (EPs). Here, we introduce a scheme for fast quantum-state synthesis using exceptional-point engineering in a lossy chain of three superconducting resonators. We theoretically find that the rich physics of EPs can be used to identify regions in the parameter space that favor a fast and quasi-stable transfer of squeezing and entanglement, or a fast reset of the system. For weakly interacting resonators with the coupling strength $g$, the obtained quasi-stabilization time scales are identified as $1/(2\sqrt{2}g)$, and reset infidelities below $10^{-5}$ are obtained with a waiting time of roughly $6/g$ in the case of weakly squeezed resonators. Our results shed light on the role of EPs in multimode Gaussian systems and pave the way for optimized distribution of squeezing and entanglement between different nodes of a photonic network using dissipation as a resource.Comment: 14 pages, 6 figure

Tyr(b10) Prevents Stabilization of Bound Oxygen in Soybean Leghemoglobin

Root nodules are complex structures that occur on roots of many agronomically important plants such as soybeans. Root nodules are a symbiosis between the plant and soil-borne bacteria. Once formed, and functional, root nodules can fix atmospheric nitrogen and provide the plant with a pollution-free source of nitrogen for seed production. A basic component of functional and efficient root nodules are the heme proteins called leghemoglobins. Leghemoglobins can bind to, and transport molecular oxygen and thereby maintain a low oxygen environment within the root nodule, permitting the microaerobic bacteria to convert atmospheric dinitrogen into ammonia, which is then assimilated by the plant for growth. Thus understanding the oxygen-binding characteristics of leghemoglobin are of major importance from both a basic and applied point of view. In this paper we have shown that specific amino acid residues are critical for allowing the orderly binding and transfer of oxygen from leghemoglobins. Although several hypotheses have been advanced to account for the biochemical properties of leghemoglobins, this work is the first that clearly demonstrates the molecular consequences of amino acids that surround the heme-pocket. Using engineered mutant proteins and spectroscopy, the role of Tyr (B10) has been investigated in detail for several vertebrate and plant hemoglobins

Genetic risk score of NOS gene variants associated with myocardial infarction correlates with coronary incidence across Europe

Coronary artery disease (CAD) mortality and morbidity is present in the European continent in a four-fold gradient across populations, from the South (Spain and France) with the lowest CAD mortality, towards the North (Finland and UK). This observed gradient has not been fully explained by classical or single genetic risk factors, resulting in some cases in the so called Southern European or Mediterranean paradox. Here we approached population genetic risk estimates using genetic risk scores (GRS) constructed with single nucleotide polymorphisms (SNP) from nitric oxide synthases (NOS) genes. These SNPs appeared to be associated with myocardial infarction (MI) in 2165 cases and 2153 controls. The GRSs were computed in 34 general European populations. Although the contribution of these GRS was lower than 1% between cases and controls, the mean GRS per population was positively correlated with coronary incidence explaining 65-85% of the variation among populations (67% in women and 86% in men). This large contribution to CAD incidence variation among populations might be a result of colinearity with several other common genetic and environmental factors. These results are not consistent with the cardiovascular Mediterranean paradox for genetics and support a CAD genetic architecture mainly based on combinations of common genetic polymorphisms. Population genetic risk scores is a promising approach in public health interventions to develop lifestyle programs and prevent intermediate risk factors in certain subpopulations with specific genetic predisposition

Insomnia as an Independent Predictor of Incident Cardiovascular Disease in HIV: Data from the Veterans Aging Cohort Study

Background: Insomnia is associated with increased cardiovascular disease (CVD) risk in the general population and is highly prevalent in people with HIV. The CVD risk conferred by insomnia in the HIV population is unknown. Methods: Using the Veterans Aging Cohort Study-Survey Cohort, insomnia symptoms were measured and dummy coded with the item, “Difficulty falling or staying asleep?” (5-point scale from no difficulty to bothers a lot). Incident CVD event ICD-9 codes (acute myocardial infarction, stroke, or coronary artery revascularization) were identified with VA and Medicare administrative data and VA fee-for-service data. Those with baseline CVD were excluded. Results: HIV-infected (N=3,108) veterans had a median follow-up time of 10.8 years, during which 267 CVD events occurred. Compared to HIV-infected veterans with no difficulty falling or staying asleep, HIV-infected veterans bothered a lot by insomnia symptoms had an increased risk of incident CVD after adjusting for demographics (HR=1.64, 95%CI=1.16-2.31, p=.005), CVD risk factors (HR=1.62, 95%CI=1.14-2.30, p=.007), additional potential confounders (hepatitis C infection, renal disease, anemia, alcohol use, cocaine use; HR=1.70, 95%CI=1.19-2.43, p=.003), and HIV-specific factors (HIV-1 RNA, CD4+ T-cell count, ART; HR=1.66, 95%CI=1.16-2.37, p=.005). Additional adjustment for non-benzodiazepine sleep medication (HR=1.62, 95%CI=1.13-2.32, p=.009) did not attenuate the association; however, it fell short of significance at p < .01 after adjustment for depressive symptoms (HR=1.51, 95%CI=0.98-2.32, p=.060) or antidepressant medication (HR=1.51, 95%CI=1.04-2.19, p=.031). Conclusion: Highly bothersome insomnia symptoms were significantly associated with incident CVD in HIV-infected veterans, suggesting that insomnia may be a novel, modifiable risk factor for CVD in HIV

HIV Infection and the Risk of World Health Organization-Defined Sudden Cardiac Death

Background People living with HIV have higher sudden cardiac death (SCD) rates compared with the general population. Whether HIV infection is an independent SCD risk factor is unclear. Methods and Results This study evaluated participants from the Veterans Aging Cohort Study, an observational, longitudinal cohort of veterans with and without HIV infection matched 1:2 on age, sex, race/ethnicity, and clinical site. Baseline for this study was a participant\u27s first clinical visit on or after April 1, 2003. Participants were followed through December 31, 2014. Using Cox proportional hazards regression, we assessed whether HIV infection, CD4 cell counts, and/or HIV viral load were associated with World Health Organization (WHO)–defined SCD risk. Among 144 336 participants (30% people living with HIV), the mean (SD) baseline age was 50.0 years (10.6 years), 97% were men, and 47% were of Black race. During follow‐up (median, 9.0 years), 3035 SCDs occurred. HIV infection was associated with increased SCD risk (hazard ratio [HR], 1.14; 95% CI, 1.04–1.25), adjusting for possible confounders. In analyses with time‐varying CD4 and HIV viral load, people living with HIV with CD4 counts \u3c 200 cells/mm3 (HR, 1.57; 95% CI, 1.28–1.92) or viral load \u3e 500 copies/mL (HR, 1.70; 95% CI, 1.46–1.98) had increased SCD risk versus veterans without HIV. In contrast, people living with HIV who had CD4 cell counts \u3e 500 cells/mm3 (HR, 1.03; 95% CI, 0.90–1.18) or HIV viral load \u3c 500 copies/mL (HR, 0.97; 95% CI, 0.87–1.09) were not at increased SCD risk. Conclusions HIV infection is associated with increased risk of WHO‐defined SCD among those with elevated HIV viral load or low CD4 cell counts

PredictABEL: an R package for the assessment of risk prediction models

The rapid identification of genetic markers for multifactorial diseases from genome-wide association studies is fuelling interest in investigating the predictive ability and health care utility of genetic risk models. Various measures are available for the assessment of risk prediction models, each addressing a different aspect of performance and utility. We developed PredictABEL, a package in R that covers descriptive tables, measures and figures that are used in the analysis of risk prediction studies such as measures of model fit, predictive ability and clinical utility, and risk distributions, calibration plot and the receiver operating characteristic plot. Tables and figures are saved as separate files in a user-specified format, which include publication-quality EPS and TIFF formats. All figures are available in a ready-made layout, but they can be customized to the preferences of the user. The package has been developed for the analysis of genetic risk prediction studies, but can also be used for studies that only include non-genetic risk factors. PredictABEL is freely available at the websites of GenABEL (http://www.genabel.org) and CRAN (http://cran.r-project.org/)

Depression and All-Cause Mortality Risk in HIV-infected and HIV-uninfected U.S. Veterans: A cohort study

Objectives: The contribution of depression to mortality in adults with and without HIV infection is unclear. We hypothesized that depression increases mortality risk and that this association is stronger among those with HIV infection. Methods: Veterans Aging Cohort Study (VACS) data were analysed from the first clinic visit on or after 1 April 2003 (baseline) to 30 September 2015. Depression definitions were: (1) major depressive disorder defined using International Classification of Diseases, Ninth Revision (ICD-9) codes; (2) depressive symptoms defined as Patient Health Questionnaire (PHQ)-9 scores ≥ 10. The outcome was all-cause mortality. Covariates were demographics, comorbid conditions and health behaviours. Results: Among 129 140 eligible participants, 30% had HIV infection, 16% had a major depressive disorder diagnosis, and 24% died over a median follow-up time of 11 years. The death rate was 25.3 [95% confidence interval (CI) 25.0-25.6] deaths per 1000 person-years. Major depressive disorder was associated with mortality [hazard ratio (HR) 1.04; 95% CI 1.01, 1.07]. This association was modified by HIV status (interaction P-value = 0.02). In HIV-stratified analyses, depression was significantly associated with mortality among HIV-uninfected veterans but not among those with HIV infection. Among those with PHQ-9 data (n = 7372), 50% had HIV infection, 22% had PHQ-9 scores ≥ 10, and 28% died over a median follow-up time of 12 years. The death rate was 27.3 (95% CI 26.1-28.5) per 1000 person-years. Depressive symptoms were associated with mortality (HR 1.16; 95% CI 1.04, 1.28). This association was modified by HIV status (interaction P-value = 0.05). In HIV-stratified analyses, depressive symptoms were significantly associated with mortality among veterans with HIV infection but not among those without HIV infection. Conclusions: Depression was associated with all-cause mortality. This association was modified by HIV status and method of depression ascertainment

Associations of Total, Cognitive/Affective, and Somatic Depressive Symptoms and Antidepressant Use With Cardiovascular Disease–Relevant Biomarkers in HIV: Veterans Aging Cohort Study

Objective We sought to determine the associations of total, cognitive/affective, and somatic depressive symptoms and antidepressant use with biomarkers of processes implicated in cardiovascular disease in HIV (HIV-CVD). Methods We examined data from 1546 HIV-positive and 843 HIV-negative veterans. Depressive symptoms were assessed using the Patient Health Questionnaire-9, and past-year antidepressant use was determined from Veterans Affair pharmacy records. Monocyte (soluble CD14 [sCD14]), inflammatory (interleukin-6 [IL-6]), and coagulation (D-dimer) marker levels were determined from previously banked blood specimens. Linear regression models with multiple imputation were run to estimate the associations between depression-related factors and CVD-relevant biomarkers. Results Among HIV-positive participants, greater somatic depressive symptoms were associated with higher sCD14 (exp[b] = 1.02, 95% confidence interval [CI] = 1.00–1.03) and D-dimer (exp[b] = 1.06, 95% CI = 1.00–1.11) after adjustment for demographics and potential confounders. Further adjustment for antidepressant use and HIV factors slightly attenuated these relationships. Associations were also detected for antidepressant use, as selective serotonin reuptake inhibitor use was related to lower sCD14 (exp[b] = 0.95, 95% CI = 0.91–1.00) and IL-6 (exp[b] = 0.86, 95% CI = 0.76–0.96), and tricyclic antidepressant use was related to higher sCD14 (exp[b] = 1.07, 95% CI = 1.03–1.12) and IL-6 (exp[b] = 1.14, 95% CI = 1.02–1.28). Among HIV-negative participants, total, cognitive/affective, and somatic depressive symptoms were associated with higher IL-6, and tricyclic antidepressant use was related to higher sCD14. Conclusions Our novel findings suggest that a) monocyte activation and altered coagulation may represent two pathways through which depression increases HIV-CVD risk and that b) tricyclic antidepressants may elevate and selective serotonin reuptake inhibitors may attenuate HIV-CVD risk by influencing monocyte and inflammatory activation

Attitudes toward Precision Treatment of Smoking in the Southern Community Cohort Study

Background: Precision interventions using biological data may enhance smoking treatment, yet are understudied among smokers who are disproportionately burdened by smoking-related disease. Methods: We surveyed smokers in the NCI-sponsored Southern Community Cohort Study, consisting primarily of African-American, low-income adults. Seven items assessed attitudes toward aspects of precision smoking treatment, from undergoing tests to acting on results. Items were dichotomized as favorable (5 = strongly agree/4 = agree) versus less favorable (1 = strongly disagree/2 = disagree/3 = neutral); a summary score reflecting generalized attitudes was also computed. Multivariable logistic regression tested independent associations of motivation (precontemplation, contemplation, and preparation) and confidence in quitting (low, medium, and high) with generalized attitudes, controlling for sociodemographic factors and nicotine dependence. Results: More than 70% of respondents endorsed favorable generalized attitudes toward precision medicine, with individual item favorability ranging from 64% to 83%. Smokers holding favorable generalized attitudes reported higher income and education (P \u3c 0.05). Predicted probabilities of favorable generalized attitudes ranged from 63% to 75% across motivation levels [contemplation vs. precontemplation: adjusted odds ratio (AOR) = 2.10, 95% confidence interval (CI), 1.36–3.25, P = 0.001; preparation vs. precontemplation: AOR = 1.83, 95% CI, 1.20–2.78, P = 0.005; contemplation vs. preparation: AOR = 1.15, 95% CI, 0.75–1.77, P = 0.52] and from 59% to 78% across confidence (medium vs. low: AOR = 1.91, 95% CI, 1.19–3.07, P = 0.007; high vs. low: AOR = 2.62, 95% CI, 1.68–4.10, P \u3c 0.001; medium vs. high: AOR = 0.73, 95% CI, 0.48–1.11, P = 0.14). Conclusions: Among disproportionately burdened community smokers, most hold favorable attitudes toward precision smoking treatment. Individuals with lower motivation and confidence to quit may benefit from additional intervention to engage with precision smoking treatment. Impact: Predominantly favorable attitudes toward precision smoking treatment suggest promise for future research testing their effectiveness and implementation

Depression as a Risk Factor for Incident Ischemic Stroke Among HIV‐Positive Veterans in the Veterans Aging Cohort Study

Background: HIV infection and depression are each associated with increased ischemic stroke risk. Whether depression is a risk factor for stroke within the HIV population is unknown. Methods and Results: We analyzed data on 106 333 (33 528 HIV-positive; 72 805 HIV-negative) people who were free of baseline cardiovascular disease from an observational cohort of HIV-positive people and matched uninfected veterans in care from April 1, 2003 through December 31, 2014. International Classification of Diseases, Ninth Revision (ICD-9) codes from medical records were used to determine baseline depression and incident stroke. Depression occurred in 19.5% of HIV-positive people. After a median of 9.2 years of follow-up, stroke rates were highest among people with both HIV and depression and lowest among those with neither condition. In Cox proportional hazard models, depression was associated with an increased risk of stroke for HIV-positive people after adjusting for sociodemographic characteristics and cerebrovascular risk factors (hazard ratio [HR], 1.18; 95% CI: 1.03-1.34; 0.014). The depression-stroke relationship was attenuated by alcohol use disorders, cocaine use, and baseline antidepressant use, and unaffected by combined antiretroviral therapy use or individual antiretroviral agents. A numerically higher HR of depression on stroke was found among those younger than 60 years. Conclusions: Depression is associated with an increased risk of stroke among HIV-positive people after adjusting for sociodemographic characteristics, traditional cerebrovascular risk factors, and HIV-specific factors. Alcohol use disorders, cocaine use, and baseline antidepressant use accounted for some of the observed stroke risk. Depression may be a novel, independent risk factor for ischemic stroke in HIV, particularly among younger people