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The capability to reach ultracold atomic temperatures in compact instruments has recently been extended into space1,2. Ultracold temperatures amplify quantum effects, whereas free fall allows further cooling and longer interactions time with gravity-the final force without a quantum description. On Earth, these devices have produced macroscopic quantum phenomena such as Bose-Einstein condensates (BECs), superfluidity, and strongly interacting quantum gases3. Terrestrial quantum sensors interfering the superposition of two ultracold atomic isotopes have tested the universality of free fall (UFF), a core tenet of Einstein's classical gravitational theory, at the 10-12 level4. In space, cooling the elements needed to explore the rich physics of strong interactions or perform quantum tests of the UFF has remained elusive. Here, using upgraded hardware of the multiuser Cold Atom Lab (CAL) instrument aboard the International Space Station (ISS), we report, to our knowledge, the first simultaneous production of a dual-species BEC in space (formed from 87Rb and 41K), observation of interspecies interactions, as well as the production of 39K ultracold gases. Operating a single laser at a 'magic wavelength' at which Rabi rates of simultaneously applied Bragg pulses are equal, we have further achieved the first spaceborne demonstration of simultaneous atom interferometry with two atomic species (87Rb and 41K). These results are an important step towards quantum tests of UFF in space and will allow scientists to investigate aspects of few-body physics, quantum chemistry and fundamental physics in new regimes without the perturbing asymmetry of gravity.
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Quantum mechanics governs the microscopic world, where low mass and momentum reveal a natural wave-particle duality. Magnifying quantum behaviour to macroscopic scales is a major strength of the technique of cooling and trapping atomic gases, in which low momentum is engineered through extremely low temperatures. Advances in this field have achieved such precise control over atomic systems that gravity, often negligible when considering individual atoms, has emerged as a substantial obstacle. In particular, although weaker trapping fields would allow access to lower temperatures1,2, gravity empties atom traps that are too weak. Additionally, inertial sensors based on cold atoms could reach better sensitivities if the free-fall time of the atoms after release from the trap could be made longer3. Planetary orbit, specifically the condition of perpetual free-fall, offers to lift cold-atom studies beyond such terrestrial limitations. Here we report production of rubidium Bose-Einstein condensates (BECs) in an Earth-orbiting research laboratory, the Cold Atom Lab. We observe subnanokelvin BECs in weak trapping potentials with free-expansion times extending beyond one second, providing an initial demonstration of the advantages offered by a microgravity environment for cold-atom experiments and verifying the successful operation of this facility. With routine BEC production, continuing operations will support long-term investigations of trap topologies unique to microgravity4,5, atom-laser sources6, few-body physics7,8 and pathfinding techniques for atom-wave interferometry9-12.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Time and income are distinct and critical resources needed in the pursuit of happiness (life satisfaction). Income can be used to purchase market goods and services, and time can be used to spend time with friends and family, rest and sleep, and other activities. Yet little research has examined how different combinations of time and income affect life satisfaction, and if more of both is positively associated with greater levels of life satisfaction. We investigate whether life satisfaction significantly varies with time and income using data from the American Time Use Survey and its well-being module, which is a nationally representative sample of over 5000 US respondents over the age of 15. We plot a three-dimensional space exploring the relationship among time, income, and life satisfaction, finding people with similar incomes with less free time have lower levels of life satisfaction. We also identify different four subpopulations, three of which have low well-being along time and income, and one with high well-being along time and income. These sub-groups significantly differ along key characteristics. Respondents with less free time and low income-the doubly poor-are more likely to be female, less educated, and have more than two kids and young children. Those with low income but lots of time, in comparison, are more likely to be black, unemployed, and have some physical or cognitive difficult. We conclude that time provides unique insights into human well-being that income alone cannot capture and should be further incorporated into research and policy on life satisfaction.
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Substance use disorders (SUDs) are thought to predict care discontinuity, though magnitude and substance-specific variance of effects are unclear. This report of analytic work undertaken with a multi-regional American cohort of 9153 care enrollees addresses these gaps. Care retention was computed from 24-month post-linkage clinic visit documentation, with SUD cases identified from patient-report screening instruments. Two generalized estimating equations tested binary and hierarchial SUD predictors of retention, and potential effect modification by patient age-group, sex, and care site. Findings demonstrate: (1) detrimental SUD effect, equivalent to a nine percentage-point decrease in retention, with independent effects of age-group and care site; (2) substance-specific effect of marijuana UD associated with lower retention; and (3) age-modification of each effect on care discontinuity, with SUDs serving as a risk factor among 18-29 year-olds and protective factor among 60+ year-olds. Collective findings document patient attributes as influences that place particular subgroups at-risk to discontinue care.
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Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/epidemiologia , Retenção nos Cuidados , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Feminino , HIV , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
Deployment of ultracold atom interferometers (AI) into space will capitalize on quantum advantages and the extended freefall of persistent microgravity to provide high-precision measurement capabilities for gravitational, Earth, and planetary sciences, and to enable searches for subtle forces signifying physics beyond General Relativity and the Standard Model. NASA's Cold Atom Lab (CAL) operates onboard the International Space Station as a multi-user facility for fundamental studies of ultracold atoms and to mature space-based quantum technologies. We report on pathfinding experiments utilizing ultracold 87Rb atoms in the CAL AI. A three-pulse Mach-Zehnder interferometer was studied to understand the influence of ISS vibrations. Additionally, Ramsey shear-wave interferometry was used to manifest interference patterns in a single run that were observable for over 150 ms free-expansion time. Finally, the CAL AI was used to remotely measure the Bragg laser photon recoil as a demonstration of the first quantum sensor using matter-wave interferometry in space.
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BACKGROUND: The Eckerd Rapid Safety Feedback Process (ERSF) is an approach to child welfare practice that combines predictive risk modeling (PRM) with real-time quality assurance and staff coaching during a child protective services investigation. During the case investigation, quality assurance (QA) reviewers provide guidance to staff by assessing key dimensions of their investigative practices and providing coaching sessions as needed. OBJECTIVE: To determine to what degree ERSF reduced the incidence of children who experienced high severity physical, sexual, or neglect maltreatment (HS-CAN) among children known to a state child welfare agency, within 12 months of the agency's involvement in a previous investigation. METHODS: This multi-year quasi-experimental study evaluated the impact of the ERSF Process on risk of repeat high severity maltreatment among children and youth identified by a PRM algorithm as high risk for experiencing repeat maltreatment and receiving the additional QA intervention, compared to those receiving the usual standard of care. RESULTS: The ERSF Process did not lower the rate of HS-CAN among children identified as high risk. The joint odds ratio for receiving ERSF given being high risk was 1.05, i.e. a point estimate indicating higher probability of future HS-CAN. CONCLUSIONS: In this statewide implementation of ERSF, we did not find a positive effect of this particular PRM-based intervention. Future maltreatment, even within 12 months of a prior investigation, may be too distal an outcome for a PRM and QA process designed to produce a high-quality CPS investigation and safety plan.
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Maus-Tratos Infantis , Adolescente , Criança , Maus-Tratos Infantis/prevenção & controle , Serviços de Proteção Infantil , Proteção da Criança , Retroalimentação , HumanosRESUMO
We examine the prospects of utilizing matter-wave Fabry-Pérot interferometers for enhanced inertial sensing applications. Our study explores such tunneling-based sensors for the measurement of accelerations in two configurations: (a) a transmission setup, where the initial wave packet is transmitted through the cavity and (b) an out-tunneling scheme with intra-cavity generated initial states lacking a classical counterpart. We perform numerical simulations of the complete dynamics of the quantum wave packet, investigate the tunneling through a matter-wave cavity formed by realistic optical potentials and determine the impact of interactions between atoms. As a consequence we estimate the prospective sensitivities to inertial forces for both proposed configurations and show their feasibility for serving as inertial sensors.
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BACKGROUND: Opioid use disorder (OUD) is a serious health condition that is effectively treated with buprenorphine. However, only a minority of people with OUD are able to access buprenorphine. Many access points for buprenorphine have high barriers for initiation and retention. Health care and drug treatment systems have not been able to provide services to all-let alone the majority-who need it, and many with OUD report extreme challenges starting and staying on buprenorphine in those care settings. We describe the design and protocol for a study of a rapid access buprenorphine program model in six Washington State communities at existing sites serving people who are unhoused and/or using syringe services programs. This study aimed to test the effectiveness of a Community-Based Medication-First Program model. METHODS: We are conducting a hybrid effectiveness-implementation study of a rapid access buprenorphine model of care staffed by prescribers, nurse care managers, and care navigators. The Community-Based Medication-First model of care was designed as a 6-month, induction-stabilization-transition model to be delivered between 2019 and 2022. Effectiveness outcomes will be tested by comparing the intervention group with a comparison group derived from state records of people who had OUD. Construction of the comparison group will align characteristics such as geography, demographics, historical rates of arrests, OUD medication, and health care utilization, using restriction and propensity score techniques. Outcomes will include arrests, emergency and inpatient health care utilization, and mortality rates. Descriptive statistics for buprenorphine utilization patterns during the intervention period will be documented with the prescription drug monitoring program. DISCUSSION: Results of this study will help determine the effectiveness of the intervention. Given the serious population-level and individual-level impacts of OUD, it is essential that services be readily available to all people with OUD, including those who cannot readily access care due to their circumstances, capacity, preferences, and related systems barriers.
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Buprenorfina , Transtornos Relacionados ao Uso de Opioides , Analgésicos Opioides/uso terapêutico , Buprenorfina/uso terapêutico , Atenção à Saúde , Humanos , Tratamento de Substituição de Opiáceos/métodos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , WashingtonRESUMO
Ultracold quantum gases are ideal sources for high-precision space-borne sensing as proposed for Earth observation, relativistic geodesy and tests of fundamental physical laws as well as for studying new phenomena in many-body physics during extended free fall. Here we report on experiments with the Cold Atom Lab aboard the International Space Station, where we have achieved exquisite control over the quantum state of single 87Rb Bose-Einstein condensates paving the way for future high-precision measurements. In particular, we have applied fast transport protocols to shuttle the atomic cloud over a millimeter distance with sub-micrometer accuracy and subsequently drastically reduced the total expansion energy to below 100 pK with matter-wave lensing techniques.
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We report the status of the Cold Atom Lab (CAL) instrument to be operated aboard the International Space Station (ISS). Utilizing a compact atom chip-based system to create ultracold mixtures and degenerate samples of 87Rb, 39K, and 41K, CAL is a multi-user facility developed by NASA's Jet Propulsion Laboratory to provide the first persistent quantum gas platform in the microgravity conditions of space. Within this unique environment, atom traps can be decompressed to arbitrarily weak confining potentials, producing a new regime of picokelvin temperatures and ultra-low densities. Further, the complete removal of these confining potential allows the free fall evolution of ultracold clouds to be observed on unprecedented timescales compared to earthbound instruments. This unique facility will enable novel ultracold atom research to be remotely performed by an international group of principle investigators with broad applications in fundamental physics and inertial sensing. Here, we describe the development and validation of critical CAL technologies, including demonstration of the first on-chip Bose-Einstein condensation (BEC) of 87Rb with microwave-based evaporation and the generation of ultracold dual-species quantum gas mixtures of 39K/87Rb and 41K/87Rb in an atom chip trap via sympathetic cooling.
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AIM: Analysis of wastewater samples can be used to assess population drug use, but reporting and statistical issues have limited the utility of the approach for epidemiology due to analytical results that are below the limit of quantification or detection. Unobserved or non-quantifiable-censored-data are common and likely to persist as the methodology is applied to more municipalities and a broader array of substances. We demonstrate the use of censored data techniques and account for measurement errors to explore distributions and annual estimates of the daily mean level of drugs excreted per capita. MEASUREMENTS: Daily 24-hour composite wastewater samples for 56days in 2009 were obtained using a random sample stratified by day of week and season for 19 municipalities in the Northwest region of the U.S. METHODS: Methamphetamine, benzoylecgonine (cocaine metabolite), 3,4 methylenedioxymethamphetamine (MDMA), methadone, oxycodone and hydrocodone were identified and quantified in wastewater samples. Four statistical approaches (reporting censoring, Maximum Likelihood Estimation, Kaplan-Meier estimates, or complete data calculations) were used to estimate an annual average, including confidence bounds where appropriate, dependent upon the amount of censoring in the data. FINDINGS: The proportion of days within a year with censored data varied greatly by drug across the 19 municipalities, with MDMA varying the most (4% to 94% of observations censored). The different statistical approaches each needed to be used given the levels of censoring of measured drug concentrations. Figures incorporating confidence bounds allow visualization of the data that facilitates appropriate comparisons across municipalities. CONCLUSIONS: Results from wastewater sampling that are below detection or quantification limits contain important information and can be incorporated to create a more complete and valid estimate of drug excretion.
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Interpretação Estatística de Dados , Drogas Ilícitas/análise , Vigilância da População/métodos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Estudos Epidemiológicos , Humanos , Oregon , WashingtonRESUMO
Influenza is an emerging and re-emerging disease. Since the late 1930s influenza viruses have been isolated yearly from different parts of the world during epidemics and pandemics. The "epidemiologic success" of influenza is due largely to rapid and unpredictable antigenic changes (antigenic drift) among human influenza viruses, and the emergence of new subtypes (antigenic shift), mostly from reassortment between human and avian influenza viruses. Antigenic shifts were attributed to the global pandemic viruses of 1957 (H2N2 Asian flu) and 1968 (H3N2 Hong Kong flu). Concern over possible new pandemics has been heightened by recent reports of human infection in Asia in 1997 with avian viruses (H5N1) and in 1999 (H9N2) and isolation of human-avian reassorted viruses from pigs and humans in Europe. Influenza has a high rate of inapparent infection, short incubation and high infectivity; epidemics usually start abruptly and spread rapidly to neighboring communities and countries. Isolation and quarantine are often unsuccessful in preventing the spread of the infection. Although not perfect, immunization and chemoprophylaxis are highly effective at minimizing the spread of influenza and reducing morbidity and mortality, social disruption and economic loss. Plans for future influenza epidemics and pandemics require national and international programs to be in place for the monitoring of influenza activity, the dissemination and exchange of information and the provision and delivery of sufficient quantities of vaccines and antiviral agents. This paper reviews and discusses the antigenic variations of the influenza virus, potential influenza pandemics, protective efficacy of inactivated vaccines and antiviral agents and preparation for control of future epidemics and pandemics.