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1.
Am J Prev Med ; 66(6): 1035-1042, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38272242

ABSTRACT

INTRODUCTION: This study investigated the prevalence of past 30-day cannabis use among U.S. youth by cigarette use, alcohol use, demographics, and state-of-residence cannabis legal status in 2021 and examined whether changes in cannabis use prevalence were modified by these factors from 2013 to 2021. METHODS: Data were drawn from the 24 states that collected cannabis use data participating in the Youth Risk Behavior Surveillance System from 2013 to 2021. Logistic regression analyses estimated past 30-day cannabis prevalence in 2021 and produced AORs by current cigarette, alcohol, and state-of-residence cannabis legal status. The same method was used with year as the exposure, adjusting for sex, race, and ethnicity, to assess trends in prevalence from 2013 to 2021. RESULTS: In 2021, cannabis use was more common among female youth (16.75% vs 13.83% [AOR=1.26, 95% CI=1.16, 1.37]) and non-Hispanic Black and Hispanic youth than among non-Hispanic White youth (17.19%, 16.14% vs 14.60% [AOR=1.25, 95% CI=1.12, 1.39 and AOR=1.16, 95% CI=1.04, 1.29, respectively]). Cannabis use was much more common among youth who reported any past 30-day cigarette or alcohol use (44.90% vs 6.48% [AOR=11.80, 95% CI=10.57, 13.18]). Declines in cannabis use were observed independent of state-level cannabis law from 2013 to 2021, and cannabis use prevalence did not differ significantly by state-of-residence cannabis legal status among the 24 participating states in 2021. CONCLUSIONS: Public health officials should carefully consider the potential impact of expanding commercialization of cannabis as a wellness product on youth cannabis use, especially with regard to minoritized populations and co-use with tobacco and alcohol. National and state-level public health education on cannabis use and youth-oriented prevention of cannabis uptake are long overdue.


Subject(s)
Alcohol Drinking , Humans , Female , Male , Adolescent , United States/epidemiology , Prevalence , Alcohol Drinking/epidemiology , Alcohol Drinking/trends , Marijuana Use/epidemiology , Marijuana Use/trends , Tobacco Use/epidemiology , Tobacco Use/trends , Marijuana Smoking/epidemiology , Marijuana Smoking/trends
2.
Pediatr Pulmonol ; 59(4): 886-890, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38240368

ABSTRACT

INTRODUCTION: Little is known about the relationship between cannabis use and asthma among youth in the US. The aims of this study were to estimate prevalence of asthma among youth who reported any cannabis use in the past 30 days, relative to those who did not, and to investigate the relationship between frequency of cannabis use and prevalence of asthma, adjusting for demographic characteristics and cigarette use. METHODS: Data were drawn from the 2019 Youth Risk Behavior Surveillance System (YRBSS), a CDC national high school survey, which collects data from students in grades 9-12 across the US bi-annually. Logistic regression was used to examine the prevalence of asthma among youth who reported any past 30-day cannabis use, relative to no use, and by frequency of cannabis use, adjusting for demographic characteristics and cigarette use. RESULTS: Asthma was more common among youth who reported any cannabis use, relative to youth who reported no use (29.07% vs. 23.62%; AOR = 1.25 (1.20, 1.30)). Asthma was greater among youth who reported more frequent cannabis use; asthma was highest among youth who reported having used cannabis "40 or more times" in the month (31.38%; AOR = 1.35 (1.25, 1.45)) CONCLUSION: Asthma is more common among youth who use cannabis, relative to those who do not, and the prevalence of asthma increases with frequency of use among 9th-12th graders in the US. More public health and clinical research is needed quickly to produce scientific data that can inform clinical guidelines and public health policy, as well as parents and youth, on the potential relationship between cannabis use and respiratory health among youth.


Subject(s)
Asthma , Cannabis , Adolescent , Humans , Prevalence , Risk-Taking , Asthma/epidemiology , Students
3.
Prev Med ; 179: 107827, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38128769

ABSTRACT

OBJECTIVES: Cannabis use has increased among adolescents and adults in the United States (US) in recent years. Few data are available on the prevalence of asthma by frequency of cannabis use. This study aimed to estimate the prevalence of asthma by frequency of past 30-day cannabis use among US individuals. METHODS: Data were drawn from the 2020 National Survey on Drug Use and Health (NSDUH), a nationally representative, annual cross-sectional survey of US individuals aged 12 and older in the United States (N = 32,893). Logistic regression models were used to examine the relationship between frequency of any cannabis and/or blunt (i.e., cannabis smoked in a hollowed-out cigar) use in the past 30 days and current asthma, adjusting for demographics and current cigarette smoking. RESULTS: Current asthma was more common among US individuals who reported cannabis use in the past 30-days, relative to those who did not (9.8% vs. 7.4%, p < 0.0001). The odds of asthma was significantly greater among individuals reporting cannabis use 20-30 days/month (Adjusted Odds Ratio [AOR] = 1.67, 95% CI:1.21, 2.31), blunt use 6-15 and 20-30 days/month (AOR = 1.9, 95% CI:1.1, 3.2; AOR = 2.2, 95% CI:1.4, 3.6), respectively, than among those without. A positive linear relationship was observed between frequency of a) cannabis use (p < 0.0001) and b) blunt use (p < 0.0001) and current asthma prevalence. CONCLUSIONS: Findings suggest a dose-response relationship between frequency of current cannabis use and the prevalence of current asthma in the US individuals.


Subject(s)
Asthma , Cannabis , Cigarette Smoking , Adult , Humans , United States/epidemiology , Adolescent , Prevalence , Cross-Sectional Studies , Cigarette Smoking/epidemiology , Asthma/epidemiology
4.
Phys Rev Appl ; 20(6)2023 Dec.
Article in English | MEDLINE | ID: mdl-38618629

ABSTRACT

III-V semiconductor quantum dots (QDs) are near-ideal and versatile single-photon sources. Because of the capacity for monolithic integration with photonic structures as well as optoelectronic and optomechanical systems, they are proving useful in an increasingly broad application space. Here, we develop monolithic circular dielectric gratings on bulk substrates - as opposed to suspended or wafer-bonded substrates - for greatly improved photon collection from InAs quantum dots. The structures utilize a unique two-tiered distributed Bragg reflector (DBR) structure for vertical electric field confinement over a broad angular range. Opposing "openings" in the cavities induce strongly polarized QD luminescence without harming collection efficiencies. We describe how measured enhancements depend on the choice of collection optics. This is important to consider when evaluating the performance of any photonic structure that concentrates farfield emission intensity. Our cavity designs are useful for integrating QDs with other quantum systems that require bulk substrates, such as surface acoustic wave phonons.

5.
J Correct Health Care ; 28(6): 396-404, 2022 12.
Article in English | MEDLINE | ID: mdl-36383107

ABSTRACT

This study sought to evaluate the association of a solitary confinement ban with self-harm among adolescents in New York City's jail system. Data were extracted from medical records on 5,038 adolescent incarcerations from October 1, 2013, through July 12, 2016, and compared incarcerations before the ban (February 20, 2015) with those after the ban. Of the 2,503 adolescent incarcerations pre-ban, there were 171 self-harm gestures among 106 incarcerations (4.2% of incarcerations). Post-ban, there were 2,100 adolescent incarcerations and 105 self-harm gestures among 71 incarcerations (3.4% of incarcerations; p < .01). The post-ban group experienced significantly lower self-harm risk compared with the pre-ban (Crude incident rate ratio, 1.35 vs. 1.81; p < .05). In adjusted analysis, the hazard of self-harm associated with solitary confinement exposure was 1.51 times that of incarcerations with no solitary exposure (p < .05) . This signifies negative health outcomes of adolescent solitary confinement and the need for policy change consideration.


Subject(s)
Jails , Self-Injurious Behavior , Adolescent , Humans , New York City/epidemiology , Self-Injurious Behavior/epidemiology
6.
Front Public Health ; 10: 735591, 2022.
Article in English | MEDLINE | ID: mdl-35774583

ABSTRACT

Objective: Central obesity has been associated with several adverse health events, but little research exists about the longitudinal effects of central obesity on multisite pain. The purpose of this study was to assess if central obesity, as measured by waist circumference measurement, was associated with an increased rate of having multisite pain among older adults aged 65 years and older. Design: The National Health and Aging Trends Study is a longitudinal cohort study initiated in 2011 and intended to be representative of Medicare beneficiaries in the contiguous United States. Methods: There were 7,145 community-dwelling participants included in this study. Data for this study were collected annually between 2011 and 2018. Researchers assessed if waist circumference risk level was associated with an increased rate ratio of multisite pain. Weighted data were used in a multivariable generalized estimating equation model that used a log link specified with a Poisson distribution. Results: Participants with high-risk waist circumferences (98 cm or greater for women and 109 cm or greater for men) had a 11% higher rate of multisite pain than those with low-risk waist circumferences [rate ratio (RR) 1.11, 95% CI: 1.07-1.15] adjusting for gender, age, race, education, probable major depression, arthritis, and multimorbidity count. Conclusion: As measured by waist circumference, central adiposity is associated with multisite pain in older adults. While more research is needed, reducing waist circumference may prove beneficial in reducing the burden of multisite pain.


Subject(s)
Medicare , Obesity, Abdominal , Aged , Body Mass Index , Female , Humans , Longitudinal Studies , Male , Obesity/epidemiology , Obesity, Abdominal/complications , Obesity, Abdominal/epidemiology , Pain/complications , Pain/epidemiology , United States/epidemiology
7.
Geriatrics (Basel) ; 6(4)2021 Oct 23.
Article in English | MEDLINE | ID: mdl-34842712

ABSTRACT

There is an integral research gap regarding whether there is a relationship between pain levels and low physical activity among older women. This is a secondary analysis of a longitudinal cohort study, the Women's Health and Aging Study (WHAS) II. Our analyses included 436 community-dwelling women between the ages of 70 and 79, who were followed for 10.5 years. We employed marginal structural modeling, which controls for time-dependent confounding, with the aim of assessing the potential direct association between pain levels and low physical activity and assess a graded relationship. Compared to women with no pain, those with widespread pain were nearly half as likely to be moderately active versus low active (aOR: 0.46, 95% confidence interval (CI): 0.22, 0.96). A graded association was observed across the four pain levels (no pain or mild pain, other pain, moderate or severe lower extremity pain, and widespread pain) on low physical activity. Our findings indicate that reducing chronic widespread pain in older women may increase moderate physical activity, and therefore reduce the downstream health risks of low physical activity, including morbidity and mortality risk.

8.
Geriatrics (Basel) ; 6(3)2021 Aug 10.
Article in English | MEDLINE | ID: mdl-34449642

ABSTRACT

Lower extremity functioning in older adults provides a measure of poor physical performance and can predict negative health outcomes. The consequences of reduced lower extremity functioning on cognitive decline, measured as time-varying variables, have not been well documented in previous studies. We aimed to evaluate whether lower extremity functioning is associated with an increased incidence rate of probable dementia among older adults using data from the National Health and Aging Trends Study (NHATS). Participants (n = 6457) were followed for 8 years to examine the relationship between lower extremity functioning, as measured by the Short Physical Performance Battery (SPPB), and incident probable dementia. Using weighted data, a multivariable Poisson regression with generalized estimating equations (GEE) was used to calculate incidence rate ratios (IRR), adjusting for covariates and clustering. Participants with low SPPB scores (0-5) had a 5% increase in incident probable dementia when compared with those who had good SPPB scores (10-12) in the adjusted model (IRR = 1.05; 95% CI = 1.04-1.07). Lower extremity functioning is associated with a modest increase in incident probable dementia. The SPPB score may be helpful in identifying subjects at risk of dementia. Efforts aimed at improving physical functioning may lead to better cognitive outcomes.

9.
Nano Lett ; 21(3): 1434-1439, 2021 Feb 10.
Article in English | MEDLINE | ID: mdl-33508204

ABSTRACT

A variety of quantum degrees of freedom, e.g., spins, valleys, and localized emitters, in atomically thin van der Waals materials have been proposed for quantum information applications, and they inevitably couple to phonons. Here, we directly measure the intrinsic optical phonon decoherence in monolayer and bulk MoS2 by observing the temporal evolution of the spectral interference of Stokes photons generated by pairs of laser pulses. We find that a prominent optical phonon mode E2g exhibits a room-temperature dephasing time of ∼7 ps in both the monolayer and bulk. This dephasing time extends to ∼20 ps in the bulk crystal at ∼15 K, which is longer than previously thought possible. First-principles calculations suggest that optical phonons decay via two types of three-phonon processes, in which a pair of acoustic phonons with opposite momentum are generated.

10.
Phys Rev Lett ; 125(6): 067403, 2020 Aug 07.
Article in English | MEDLINE | ID: mdl-32845682

ABSTRACT

Multidimensional coherent spectroscopy directly unravels multiply excited states that overlap in a linear spectrum. We report multidimensional coherent optical photocurrent spectroscopy in a semiconductor polariton diode and explore the excitation ladder of cavity polaritons. We measure doubly and triply avoided crossings for pairs and triplets of exciton polaritons, demonstrating the strong coupling between light and dressed doublet and triplet semiconductor excitations. These results demonstrate that multiply excited excitonic states strongly coupled to a microcavity can be described as two coupled quantum-anharmonic ladders.

11.
Opt Express ; 28(11): 16057-16072, 2020 May 25.
Article in English | MEDLINE | ID: mdl-32549437

ABSTRACT

W centers are trigonal defects generated by self-ion implantation in silicon that exhibit photoluminescence at 1.218 µm. We have shown previously that they can be used in waveguide-integrated all-silicon light-emitting diodes (LEDs). Here we optimize the implant energy, fluence and anneal conditions to maximize the photoluminescence intensity for W centers implanted in silicon-on-insulator, a substrate suitable for waveguide-integrated devices. After optimization, we observe near two orders of magnitude improvement in photoluminescence intensity relative to the conditions with the stopping range of the implanted ions at the center of the silicon device layer. The previously demonstrated waveguide-integrated LED used implant conditions with the stopping range at the center of this layer. We further show that such light sources can be manufactured at the 300-mm scale by demonstrating photoluminescence of similar intensity from 300 mm silicon-on-insulator wafers. The luminescence uniformity across the entire wafer is within the measurement error.

12.
Psychiatr Serv ; 71(6): 547-554, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32041509

ABSTRACT

OBJECTIVE: New York City's (NYC) Correctional Health Services has introduced specialized treatment units for patients with serious mental illness in the NYC jail system. With multidisciplinary mental health staffing and a coordinated approach with NYC's Department of Correction, these units expand therapeutic options for patients vulnerable to clinical instability and physical harm, including those at high risk of psychiatric medication nonadherence and those returning to jail from psychiatric hospitalization. This study evaluated the extent to which these units improve clinical outcomes for this population. METHODS: This retrospective, observational cohort study included adult males with serious mental illness with a length of jail stay of ≥14 days between January 1, 2016, and March 31, 2018. Patients on treatment units were matched with patients of similar characteristics (control group) by using propensity score matching (N=302 pairs). Rates of self-injury, injury due to violence, and psychiatric medication adherence were analyzed. RESULTS: Most patients on treatment units had diagnoses of schizophrenia spectrum and other psychotic disorders (81%), and most had a violent felony as their most severe charge (68%). Compared with patients in a control group, those on the treatment units had lower rates per 100 person-days of injury due to violence at 30 and 60 days (0.04, 95% confidence interval [CI]=0.02-0.07, and 0.03, 95% CI=0.02-0.06, respectively) and higher mean medication adherence (77% versus 55%, p<0.001). They also experienced lower rates of self-injury, although the difference was not statistically significant. CONCLUSIONS: Initial outcomes indicate substantial benefits to patients, demonstrating the value of a rehabilitative approach to psychiatric care in jail.


Subject(s)
Jails/organization & administration , Medication Adherence/statistics & numerical data , Mental Health Services/organization & administration , Psychotic Disorders/therapy , Self-Injurious Behavior/prevention & control , Adolescent , Adult , Hospital Units , Humans , Male , Middle Aged , New York City , Retrospective Studies , Young Adult
13.
Nature ; 567(7746): 71-75, 2019 03.
Article in English | MEDLINE | ID: mdl-30804527

ABSTRACT

Recent advances in the isolation and stacking of monolayers of van der Waals materials have provided approaches for the preparation of quantum materials in the ultimate two-dimensional limit1,2. In van der Waals heterostructures formed by stacking two monolayer semiconductors, lattice mismatch or rotational misalignment introduces an in-plane moiré superlattice3. It is widely recognized that the moiré superlattice can modulate the electronic band structure of the material and lead to transport properties such as unconventional superconductivity4 and insulating behaviour driven by correlations5-7; however, the influence of the moiré superlattice on optical properties has not been investigated experimentally. Here we report the observation of multiple interlayer exciton resonances with either positive or negative circularly polarized emission in a molybdenum diselenide/tungsten diselenide (MoSe2/WSe2) heterobilayer with a small twist angle. We attribute these resonances to excitonic ground and excited states confined within the moiré potential. This interpretation is supported by recombination dynamics and by the dependence of these interlayer exciton resonances on twist angle and temperature. These results suggest the feasibility of engineering artificial excitonic crystals using van der Waals heterostructures for nanophotonics and quantum information applications.

14.
Phys Rev Lett ; 121(5): 057403, 2018 Aug 03.
Article in English | MEDLINE | ID: mdl-30118275

ABSTRACT

In atomically thin two-dimensional semiconductors such as transition metal dichalcogenides (TMDs), controlling the density and type of defects promises to be an effective approach for engineering light-matter interactions. We demonstrate that electron-beam irradiation is a simple tool for selectively introducing defect-bound exciton states associated with chalcogen vacancies in TMDs. Our first-principles calculations and time-resolved spectroscopy measurements of monolayer WSe_{2} reveal that these defect-bound excitons exhibit exceptional optical properties including a recombination lifetime approaching 200 ns and a valley lifetime longer than 1 µs. The ability to engineer the crystal lattice through electron irradiation provides a new approach for tailoring the optical response of TMDs for photonics, quantum optics, and valleytronics applications.

15.
J Phys Chem Lett ; 8(5): 1099-1104, 2017 Mar 02.
Article in English | MEDLINE | ID: mdl-28212035

ABSTRACT

The detailed pathways of photoactivity on ultrafast time scales are a topic of contemporary interest. Using a tabletop apparatus based on a laser plasma X-ray source and an array of cryogenic microcalorimeter X-ray detectors, we measured a transient X-ray absorption spectrum during the ferrioxalate photoreduction reaction. With these high-efficiency detectors, we observe the Fe K edge move to lower energies and the amplitude of the extended X-ray absorption fine structure reduce, consistent with a photoreduction mechanism in which electron transfer precedes disassociation. These results are compared to previously published transient X-ray absorption measurements on the same reaction and found to be consistent with the results from Ogi et al. and inconsistent with the results of Chen et al. ( Ogi , Y. ; et al. Struct. Dyn. 2015 , 2 , 034901 ; Chen , J. ; Zhang , H. ; Tomov , I. V. ; Ding , X. ; Rentzepis , P. M. Chem. Phys. Lett. 2007 , 437 , 50 - 55 ). We provide quantitative limits on the Fe-O bond length change. Finally, we review potential improvements to our measurement technique, highlighting the future potential of tabletop X-ray science using microcalorimeter sensors.

16.
Appl Phys Lett ; 111(14)2017.
Article in English | MEDLINE | ID: mdl-36452265

ABSTRACT

We demonstrate cryogenic, electrically injected, waveguide-coupled Si light-emitting diodes (LEDs) operating at 1.22 µm. The active region of the LED consists of W centers implanted in the intrinsic region of a p-i-n diode. The LEDs are integrated on waveguides with superconducting nanowire single-photon detectors (SNSPDs). We demonstrate the scalability of this platform with an LED coupled to eleven SNSPDs in a single integrated photonic device.

17.
Optica ; 3(12): 1397-1403, 2016 Dec.
Article in English | MEDLINE | ID: mdl-29170754

ABSTRACT

The amplitude and phase of a material's nonlinear optical response provide insight into the underlying electronic dynamics that determine its optical properties. Phase-sensitive nonlinear spectroscopy techniques are widely implemented to explore these dynamics through demodulation of the complex optical signal field into its quadrature components; however, complete reconstruction of the optical response requires measuring both the amplitude and phase of each quadrature, which is often lost in standard detection methods. Here, we implement a heterodyne-detection scheme to fully reconstruct the amplitude and phase response of spectral hole-burning from InAs/GaAs charged quantum dots. We observe an ultra-narrow absorption profile and a corresponding dispersive lineshape of the phase, which reflect the nanosecond optical coherence time of the charged exciton transition. Simultaneously, the measurements are sensitive to electron spin relaxation dynamics on a millisecond timescale, as this manifests as a magnetic-field dependent delay of the amplitude and phase modulation. Appreciable amplitude modulation depth and nonlinear phase shift up to ~0.09×π radians (16°) are demonstrated, providing new possibilities for quadrature modulation at faint photon levels with several independent control parameters, including photon number, modulation frequency, detuning, and externally applied fields.

18.
Opt Express ; 21(23): 28617-27, 2013 Nov 18.
Article in English | MEDLINE | ID: mdl-24514373

ABSTRACT

Multidimensional Coherent Optical Photocurrent Spectroscopy (MD-COPS) is implemented using unstabilized interferometers. Photocurrent from a semiconductor sample is generated using a sequence of four excitation pulses in a collinear geometry. Each pulse is frequency shifted by a unique radio frequency through acousto-optical modulation; the Four-Wave Mixing (FWM) signal is then selected in the frequency domain. The interference of an auxiliary continuous wave laser, which is sent through the same interferometers as the excitation pulses, is used to synthesize reference frequencies for lock-in detection of the photocurrent FWM signal. This scheme enables the partial compensation of mechanical fluctuations in the setup, achieving sufficient phase stability without the need for active stabilization. The method intrinsically provides both the real and imaginary parts of the FWM signal as a function of inter-pulse delays. This signal is subsequently Fourier transformed to create a multi-dimensional spectrum. Measurements made on the excitonic resonance in a double InGaAs quantum well embedded in a p-i-n diode demonstrate the technique.

19.
Opt Express ; 18(13): 13385-95, 2010 Jun 21.
Article in English | MEDLINE | ID: mdl-20588468

ABSTRACT

We describe an operating regime for passively mode-locked quantum dot diode laser where the output consists of a train of dark pulses, i.e., intensity dips on a continuous background. We show that a dark pulse train is a solution to the master equation for mode-locked lasers. Using simulations, we study stability of the dark pulses and show they are consistent with the experimental results.


Subject(s)
Computer Simulation , Lasers, Semiconductor , Optics and Photonics/instrumentation , Quantum Dots , Equipment Design , Models, Theoretical , Optics and Photonics/methods , Semiconductors
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