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1.
Phys Rev Lett ; 132(19): 193803, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38804954

ABSTRACT

We investigate the transmission of vector beams, correlated in their polarization and spatial degrees of freedom, through cold atoms in the presence of a transverse magnetic coupling field. The resulting phase-dependent dynamics allow us to imprint the spatially varying polarization of a vector beam onto atomic spin polarizations, thereby establishing a direct link between optical space-polarization correlations and atomic-state interference. We find that the resulting absorption profiles show interference fringes whose modulation strength is given by the squared concurrence of the vector beam, letting us identify optical concurrence from a single absorption image. We expect impact across a diverse range of applications, including spintronics, quantum memories, metrology, and clocks.

2.
Opt Express ; 30(11): 19812-19823, 2022 May 23.
Article in English | MEDLINE | ID: mdl-36221748

ABSTRACT

We numerically investigate the transfer of optical information from a vector-vortex control beam to an unstructured probe beam, as mediated by an atomic vapour. The right and left circular components of these beams drive the atomic transitions of a double-V system, with the atoms acting as a spatially varying circular birefringent medium. Modeling the propagation of the light fields, we find that, for short distances, the vectorial light structure is transferred from the control field to the probe. However, for larger propagation lengths, diffraction causes the circular components of the probe field to spatially separate. We model this system for the D1 line of cold rubidium atoms and demonstrate that four wave mixing can lead to correlations between the optical polarization structure and the diffraction of light, generating coupled dynamics of the internal and external degrees of freedom.

3.
Addict Behav ; 130: 107292, 2022 07.
Article in English | MEDLINE | ID: mdl-35248884

ABSTRACT

Addictive behavior sometimes involves harmful moral transgressions for which the addicted individual may be blamed. However, blame may motivate addiction stigma, which has its own harmful consequences, including failures to provide or seek out treatment and recovery resources. Minimizing blame and stigma, while acknowledging the moral dimension of addictive behavior, thus recommends itself as a worthy public health objective. The disease and choice models of addiction both face difficulties in reducing stigma, the latter because harmful choices are considered culpable. By challenging the widely held libertarian conception of human agency, an explicitly deterministic understanding of the genesis and expression of addiction, including voluntary choices, can help keep reactive attitudes to wrongdoing in check. This will mitigate the perceived blameworthiness of addicted individuals, thus reducing stigma and increasing the chances of finding compassionate and effective care. Such an approach to addiction will recognize the need for moral accountability but not include punitive attitudes and policies justified by belief in libertarian agency.


Subject(s)
Behavior, Addictive , Humans , Morals , Social Stigma
4.
Phys Rev Lett ; 127(23): 233202, 2021 Dec 03.
Article in English | MEDLINE | ID: mdl-34936773

ABSTRACT

We describe and demonstrate how 3D magnetic field alignment can be inferred from single absorption images of an atomic cloud. While optically pumped magnetometers conventionally rely on temporal measurement of the Larmor precession of atomic dipoles, here a cold atomic vapor provides a spatial interface between vector light and external magnetic fields. Using a vector vortex beam, we inscribe structured atomic spin polarization in a cloud of cold rubidium atoms and record images of the resulting absorption patterns. The polar angle of an external magnetic field can then be deduced with spatial Fourier analysis. This effect presents an alternative concept for detecting magnetic vector fields and demonstrates, more generally, how introducing spatial phases between atomic energy levels can translate transient effects to the spatial domain.

5.
Environ Toxicol Chem ; 39(2): 396-409, 2020 02.
Article in English | MEDLINE | ID: mdl-31645081

ABSTRACT

Since 2009, the Canadian and Alberta governments have been developing monitoring plans for surface water quality and quantity of the lower Athabasca River and its tributaries (2010-2013). The objectives of the present study to the fish monitoring program were to 1) assess the current status of fish in a tributary of the lower Athabasca River, 2) identify existing differences between upstream reference and within the oil sands deposit exposure sites, and 3) identify trends/changes in fish performance indicators relative to historical studies. The present study examines the fish performance indicators in slimy sculpin (Cottus cognatus) in the Steepbank River, Alberta, in terms of growth, gonad size, condition, and hepatic 7-ethoxyresorufin-O-deethylase (EROD) activity as an indicator of exposure to oil-sands-related compounds. The sampling program followed historical sampling methods (1999-2000) to provide comparable data over time with an additional upstream site (n = 2) added as development progressed. Consistent changes were documented in sculpin collected from downstream sections of the Steepbank River within the oil sands deposit (n = 2) in 2010 through 2013. Sculpin demonstrated increased liver size with corresponding induction of EROD activity consistent with historical data and reductions in energy investment relative to reproductive development and gonadal steroid production capacity. There was no consistent evidence of changes in fish performance indicators with increased surface mining development, particularly adjacent to the Steepbank River Mid site. Although physical development in the Steepbank watershed has increased over the last 15 yr, these results are consistent with historical data suggesting that the magnitude of the response in the aquatic environment adjacent to the development has not changed. Environ Toxicol Chem 2020;39:396-409. © 2019 SETAC.


Subject(s)
Environmental Monitoring/methods , Mining , Oil and Gas Fields , Perciformes/growth & development , Rivers/chemistry , Water Pollutants, Chemical/toxicity , Alberta , Animals , Cytochrome P-450 CYP1A1/metabolism , Gonads/drug effects , Gonads/growth & development , Gonads/metabolism , Perciformes/metabolism , Water Pollutants, Chemical/analysis
6.
Opt Express ; 26(14): 18513-18522, 2018 Jul 09.
Article in English | MEDLINE | ID: mdl-30114030

ABSTRACT

The interaction of spatially structured light fields with atomic media can generate spatial structures inscribed in the atomic populations and coherences, allowing for example the storage of optical images in atomic vapours. Typically, this involves coherent optical processes based on Raman or EIT transitions. Here we study the simpler situation of shaping atomic populations via spatially dependent optical depletion. Using a near resonant laser beam with a holographically controlled 3D intensity profile, we imprint 3D population structures into a thermal rubidium vapour. This 3D population structure is simultaneously read out by recording the spatially resolved fluorescence of an unshaped probe laser. We find that the reconstructed atomic population structure is largely complementary to the intensity structure of the control beam, however appears blurred due to global repopulation processes. We identify and model these mechanisms which limit the achievable resolution of the 3D atomic population. We expect this work to set design criteria for future 2D and 3D atomic memories.

7.
Opt Express ; 24(6): 6249-64, 2016 Mar 21.
Article in English | MEDLINE | ID: mdl-27136818

ABSTRACT

Whether in art or for QR codes, images have proven to be both powerful and efficient carriers of information. Spatial light modulators allow an unprecedented level of control over the generation of optical fields by using digital holograms. There is no unique way of obtaining a desired light pattern however, leaving many competing methods for hologram generation. In this paper, we test six hologram generation techniques in the creation of a variety of modes as well as a photographic image: rating the methods according to obtained mode quality and power. All techniques compensate for a non-uniform mode profile of the input laser and incorporate amplitude scaling. We find that all methods perform well and stress the importance of appropriate spatial filtering. We expect these results to be of interest to those working in the contexts of microscopy, optical trapping or quantum image creation.

8.
Annu Rev Public Health ; 36: 559-74, 2015 Mar 18.
Article in English | MEDLINE | ID: mdl-25581144

ABSTRACT

Public health authorities have described, with growing alarm, an unprecedented increase in morbidity and mortality associated with use of opioid pain relievers (OPRs). Efforts to address the opioid crisis have focused mainly on reducing nonmedical OPR use. Too often overlooked, however, is the need for preventing and treating opioid addiction, which occurs in both medical and nonmedical OPR users. Overprescribing of OPRs has led to a sharp increase in the prevalence of opioid addiction, which in turn has been associated with a rise in overdose deaths and heroin use. A multifaceted public health approach that utilizes primary, secondary, and tertiary opioid addiction prevention strategies is required to effectively reduce opioid-related morbidity and mortality. We describe the scope of this public health crisis, its historical context, contributing factors, and lines of evidence indicating the role of addiction in exacerbating morbidity and mortality, and we provide a framework for interventions to address the epidemic of opioid addiction.


Subject(s)
Epidemics/prevention & control , Heroin Dependence/prevention & control , Opioid-Related Disorders/prevention & control , Prescription Drug Misuse/prevention & control , Public Health/methods , Epidemics/statistics & numerical data , Heroin Dependence/epidemiology , Humans , Inappropriate Prescribing/prevention & control , Inappropriate Prescribing/statistics & numerical data , Opioid-Related Disorders/epidemiology , Prescription Drug Misuse/statistics & numerical data , Primary Prevention/methods , Secondary Prevention/methods , Tertiary Prevention/methods , United States/epidemiology
9.
Pharmacoepidemiol Drug Saf ; 23(9): 950-7, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24920376

ABSTRACT

PURPOSE: To describe prescriber response to unsolicited patient reports from the Massachusetts prescription drug monitoring program (PDMP). METHODS: Prescribers were surveyed upon receipt of unsolicited reports of their patients' prescription history and three months later. We assessed prescribers' awareness of other prescribers listed in the report, their clinical assessment of medical necessity of all prescribed medications, actions taken by prescribers after receiving the report, and usefulness of the report. RESULTS: Of the 333 respondents to the initial survey, only 28 (8.4%) were aware of most, all, or nearly all other prescribers. A total of 146 (43.8%) reported having sufficient knowledge to determine whether the prescriptions were medically necessary, of whom 102 (69.6%) felt the prescriptions were unwarranted. Of the 163 respondents to the follow-up survey, 31.3% added the report to the patient's file, 22.7% discussed the report with other prescribers on the report, 21.5% took no action, and 6% discussed the report with the patient (representing two-thirds of respondents who saw the patient after receiving the report). Most respondents felt that the report was useful for their practice and easy to understand. CONCLUSIONS: Unsolicited reporting of PDMP data has the potential to improve clinical practice by alerting providers about patients with multiple prescribers and potentially medically unnecessary prescriptions.


Subject(s)
Physicians/statistics & numerical data , Practice Patterns, Physicians'/statistics & numerical data , Prescription Drug Misuse/statistics & numerical data , Prescription Drugs/administration & dosage , Data Collection/methods , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Massachusetts
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