Quantum state transfer between field and atoms in Electromagnetically Induced Transparency

We show that a quasi-perfect quantum state transfer between an atomic ensemble and fields in an optical cavity can be achieved in Electromagnetically Induced Transparency (EIT). A squeezed vacuum field state can be mapped onto the long-lived atomic spin associated to the ground state sublevels of the Lambda-type atoms considered. The EIT on-resonance situation show interesting similarities with the Raman off-resonant configuration. We then show how to transfer the atomic squeezing back to the field exiting the cavity, thus realizing a quantum memory-type operation.Comment: 8 pages, 4 figure

Reversible Quantum Interface for Tunable Single-sideband Modulation

Using Electromagnetically Induced Transparency (EIT) in a Cesium vapor, we demonstrate experimentally that the quantum state of a light beam can be mapped into the long lived Zeeman coherences of an atomic ground state. Two non-commuting variables carried by light are simultaneously stored and subsequentely read-out, with no noise added. We compare the case where a tunable single sideband is stored independently of the other one to the case where the two symmetrical sidebands are stored using the same EIT transparency window.Comment: 4 pages, 6 figure

Continuous variable entanglement using cold atoms

We present experimental demonstration of quadrature and polarization entanglement generated via the interaction between a coherent linearly polarized field and cold atoms in a high finesse optical cavity. The non linear atom-field interaction produces two squeezed modes with orthogonal polarizations which are used to generate a pair of non separable beams, the entanglement of which is demonstrated by checking the inseparability criterion for continuous variables recently derived by Duan et al. [Phys. Rev. Lett. 84, 2722 (2000)] and calculating the entanglement of formation [Giedke et al., Phys. Rev. Lett. 91, 107901 (2003)]

Long-lived quantum memory with nuclear atomic spins

We propose to store non-classical states of light into the macroscopic collective nuclear spin ($10^{18}$ atoms) of a $^3$He vapor, using metastability exchange collisions. These collisions, commonly used to transfer orientation from the metastable state $2^{3}S\_1$ to the ground state state of $^3$He, can also transfer quantum correlations. This gives a possible experimental scheme to map a squeezed vacuum field state onto a nuclear spin state with very long storage times (hours).Comment: 4 page

A Cross-Sectional Exploration of Food Security, Depression, and CHAOS in Low-Income Households with Children

Depression has been linked to food security, particularly among low-income mothers. However, less is known about the relationship between CHAOS (Confusion, Hubbub, and Order Scale), a measure of family functioning such as timeliness and order, and varying levels food security. The purpose of this paper was to evaluate the relationship between depression, CHAOS, and sociodemographics on the level of food insecurity in a cross-sectional sample of low-income households with children, ages 0-18 years. Participants were recruited from low-income communities in a medium sized Midwestern city in the United States. Eligible participants were ≥19 years of age, a parent or primary caregiver to at least one child, and English- or Spanish- speaking. Survey items included participation in the Supplemental Nutrition Assistance Program (SNAP), food security, depression, CHAOS, and sociodemographics/family characteristics. Descriptives and Chi-square tests were conducted for all variables. Potential covariates were assessed (e.g., age, income, education, race/ethnicity, sex, SNAP participation, number of children and adults in the household, and marital status) and included in the final logistic regression model through backward elimination. All statistics were conducted using SAS (version 9.4, SAS Institute Inc., Cary, NC). Participants (N=252) were 75% female, 42% Non-Hispanic Black, 31% Non-Hispanic White, 12% Hispanic, and 15% other race categories. The mean number of children in households was 2.33 (SD=1.58), and half of the respondents reported earning ≤$10,000/year. Chi-Square tests showed univariate relationships between study variables and varying household food security levels. Those in the “high” and “medium” groups for depression and CHAOS were both more likely than the “low” groups to experience low or very low food security. Income and education were also related to food security, with low levels of education and low income being associated with low or very low food security. Age, sex, race/ethnicity, and marital status were not associated with food security status. The fully adjusted logistic regression models of depression and CHAOS accounted for 10% and 14% of the variance in food security, respectively (depression: (OR=0.31, CI=0.15-0.65; pp In the current study, CHAOS demonstrated a stronger relationship with food security than depression, when controlling for sociodemographics. CHAOS is a measurement that has not been tested widely among food insecure populations, but has been shown to be an influencing factor on child development, and might help explain some of the stress experienced by low-income families. Understanding more about the psychological aspects of food insecurity may help inform the development of tailored interventions to alleviate food insecurity in low-income households, and ultimately improve health, achievement and related outcomes in children

Food Security, Hunger-coping, and Hunger-Symptoms, and Their Relationship With Daily Fruit and Vegetable Intake Frequency in a Low-income Sample

Purpose To examine daily fruit and vegetable (FV) intake frequency by household food security status (high food security, marginal food security, low food security, and very low food security), and scores on three hunger-coping behavior scales (i.e., “rationing food supplies”, “financial strategies”, and “trade-off strategies”), and one physiological hunger symptoms scale among a very low-income population in the Midwestern United States. Methods Adult participants (aged 19 and older and caregivers to at least one child aged 0-18) were recruited from public libraries, food pantries, and other community locations to participate in a cross-sectional self-administered survey (n = 306). The primary outcome variable was daily FV intake frequency, measured from five items from the 16-item NYPANS dietary screener (fruit, green salad, carrots, other vegetables, and non-fried potatoes). These items were converted into daily frequencies and then summed. Daily FV intake frequency was also log transformed to meet statistical model assumptions. The main independent variables in this study were household food security (measured using the 6-item USDA Household Food Security Survey Module), scores on three 5-item hunger-coping behavior scales (max scores = 5), and one 5-item physiological hunger symptoms scale (max scores = 5). Potential sociodemographic and household characteristics (e.g., sex, age, race/ethnicity, education, income, marital status, food assistance, income assistance, food pantry use, household child to adult ratio, and automobile access) were assessed as potential covariates. Generalized linear models were used to assess the relationship between independent variables and daily FV intake frequency. Results 278 participants provided complete data for the outcome variable and were included in the sample. The sample was 73% female, 45% African American, 14% Hispanic, and 28% Caucasian. A majority of participants (60%) reported annual household incomes under $15,000. A high proportion of participants (42%) had very lowfood security, as compared to the national average of 6%. Participants reported consuming FV 2.40 times per day (SD=1.76) on average. Compared the high food secure group (In adjusted models), being in the “very low” food security group was associated with a 26% decrease, on average, in daily FV intake frequency (exp(β)=0.74, 95%CI=0.61-0.88, p Conclusions Compared to the high food secure group, those in the “very low” food secure group reported a significantly lower mean daily FV intake frequency, but not those in the “low” food secure group. This emphasizes the need to examine the “low” and “very low” food secure groups separately when studying factors associated with diet. Engaging in hunger-coping behaviors and experiencing physiological hunger symptoms was associated with decreased daily FV intake frequency. It is not clear if the hunger coping-behaviors themselves directly lead to decreased daily FV intake frequency, or if they were a marker for food insecurity and associated economic distress. These constructs and relationships should be examined in future studies. Programs and policies, which seek to promote fruit and vegetable intake among low-income populations, should target the “very low” food secure as the most at-risk for low intake. Also, researchers and community organizations working with food insecure groups could potentially measure hunger-coping behaviors and hunger symptoms in a complementary fashion to traditional measures of food insecurity to gain more contextual information about the experiences of this population

Improved Tropical Forest Management for Carbon Retention

Using reduced-impact timber-harvesting practices in legally logged tropical forests would reduce global carbon emissions by 0.16 Gt/year at a modest cost and with little risk of "leakage" (increased carbon emissions elsewhere)

Monthly SNAP benefit duration and its association with food security, hunger-coping, and physiological hunger symptoms among low-income families

Purpose The purpose of this study was to examine relationships between monthly Supplemental Nutrition Assistance Program (SNAP) benefit duration (i.e., the number of weeks each month a participants’ SNAP benefits provide food), and five primary outcome variables: food security, three hunger-coping behavior scales (rationing food supplies, financial strategies, making trade-offs), and physiological hunger symptoms, among a sample of families with children 0-18 years currently receiving SNAP benefits. Methods Baseline survey data were collected as part of a community-based intervention to alleviate child hunger. Participants included in the analytic sample were current SNAP recipients, parents (or caregivers), and 19 years of age and older (n=161). The survey assessed sociodemographics, household characteristics, food and financial assistance use, food security, three hunger-coping behavior scales, diet intake frequency, and one physiological hunger symptoms scale. The three hunger-coping scales and the physiological hunger scale were dichotomized into a “high” group (if above the sample median score) and a “low” group (if at or below the sample median score). Sociodemographic and family characteristics were included as covariates. Logistic regression models were used to assess relationships between monthly SNAP benefit duration and the five primary outcome variables in this study. Results Respondents were predominately mothers/female caregivers (78%), a majority reported annual family incomes below $10,000 (58%), and 80% were experiencing “low” or “very low” food security. The sample was 43% non-Hispanic black, 30% non-Hispanic white, 10% Hispanic/Latino, 17% American Indian or other racial/ethnic groups. Monthly SNAP benefit duration (M=2.8, SD=1.0) was not likely driven by allotment amount, because households’ percent of the federal poverty line (a proxy measure for allotment amount) was not associated with the number of weeks each month that benefits lasted (p=0.36). After controlling for relevant sociodemographic variables and household characteristics, the more weeks each month participants reported their SNAP benefits lasting, the lower their odds of experiencing “low” or “very low” food security (OR=0.444, 95%CI=0.259-0.761; p Conclusions These findings suggest that monthly SNAP benefit duration may be useful as a proxy for SNAP allotment adequacy in the context of food security and hunger. Families that were not able to make monthly benefits extend as long as other families were more likely to be food insecure and experience “high” levels of physiological hunger symptoms. While associations with hunger-coping behaviors were only significant in univariate analysis, they were in the direction expected and should be further examined in future studies as these behaviors may be exacerbate, buffer, or be symptoms of the experience of food insecurity and hunger among low-income families. Policies are needed to better tailor SNAP benefit allotments to the needs of disadvantaged families, and research and programming is needed to investigate ways these families can better utilize their current allotments as a potential path to address food insecurity and hunger

Brain serotonin synthesis capacity in obsessive-compulsive disorder: effects of cognitive behavioral therapy and sertraline.

Cognitive behavioral therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs) are both effective treatments for some patients with obsessive-compulsive disorder (OCD), yet little is known about the neurochemical changes related to these treatment modalities. Here, we used positron emission tomography and the α-[11C]methyl-L-tryptophan tracer to examine the changes in brain regional serotonin synthesis capacity in OCD patients following treatment with CBT or SSRI treatment. Sixteen medication-free OCD patients were randomly assigned to 12 weeks of either CBT or sertraline treatment. Pre-to-post treatment changes in the α-[11C]methyl-L-tryptophan brain trapping constant, K* (ml/g/min), were assessed as a function of symptom response, and correlations with symptom improvement were examined. Responders/partial responders to treatment did not show significant changes in relative regional tracer uptake; rather, in responders/partial responders, 12 weeks of treatment led to serotonin synthesis capacity increases that were brain-wide. Irrespective of treatment modality, baseline serotonin synthesis capacity in the raphe nuclei correlated positively with clinical improvement. These observations suggest that, for some patients, successful remediation of OCD symptoms might be associated with greater serotonergic tone

Measurement of Thermal Noise in Multilayer Coatings with Optimized Layer Thickness

A standard quarter-wavelength multilayer optical coating will produce the highest reflectivity for a given number of coating layers, but in general it will not yield the lowest thermal noise for a prescribed reflectivity. Coatings with the layer thicknesses optimized to minimize thermal noise could be useful in future generation interferometric gravitational wave detectors where coating thermal noise is expected to limit the sensitivity of the instrument. We present the results of direct measurements of the thermal noise of a standard quarter-wavelength coating and a low noise optimized coating. The measurements indicate a reduction in thermal noise in line with modeling predictions.Comment: 8 pages, 14 figure