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1.
Phys Chem Chem Phys ; 26(23): 16589-16596, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38814318

ABSTRACT

Isolated mixed-ligand complexes provide tractable model systems in which to study competitive and cooperative binding effects as well as controlled energy flow. Here, we report spectroscopic and isotopologue-selective infrared photofragmentation dynamics of mixed gas-phase Au(12/13CO)n(N2O)m+ complexes. The rich infrared action spectra, which are reproduced well using simulations of calculated lowest energy structures, clarify previous ambiguities in the assignment of vibrational bands, especially accidental coincidence of CO and N2O bands. The fragmentation dynamics exhibit the same unexpected behaviour as reported previously in which, once CO loss channels are energetically accessible, these dominate the fragmentation branching ratios, despite the much lower binding energy of N2O. We have investigated the dynamics computationally by considering anharmonic couplings between a relevant subset of normal modes involving both ligand stretch and intermolecular modes. Discrepancies between correlated and uncorrelated model fit to the ab initio potential energy curves are quantified using a Boltzmann sampled root mean squared deviation providing insight into efficiency of vibrational energy transfer between high frequency ligand stretches and the softer intermolecular modes which break during fragmentation.

2.
Prev Med ; 172: 107538, 2023 07.
Article in English | MEDLINE | ID: mdl-37156430

ABSTRACT

Financial incentives are a controversial strategy for increasing vaccination. In this systematic review, we evaluated: 1) the effects of incentives on COVID-19 vaccinations; 2) whether effects differed based on study outcome, study design, incentive type and timing, or sample sociodemographic characteristics; and 3) the cost of incentives per additional vaccine administered. We searched PubMed, EMBASE, Scopus, and Econlit up to March 2022 for terms related to COVID, vaccines, and financial incentives, and identified 38 peer-reviewed, quantitative studies. Independent raters extracted study data and evaluated study quality. Studies examined the impact of financial incentives on COVID-19 vaccine uptake (k = 18), related psychological outcomes (e.g., vaccine intentions, k = 19), or both types of outcomes. For studies of vaccine uptake, none found that financial incentives had a negative effect on uptake, and most rigorous studies found that incentives had a positive effect on uptake. By contrast, studies of vaccine intentions were inconclusive. While three studies concluded that incentives may negatively impact vaccine intentions for some individuals, they had methodological limitations. Study outcomes (uptake versus intentions) and study design (experimental versus observational frameworks) appeared to influence results more than incentive type or timing. Additionally, income and political affiliation may moderate responses to incentives. Most studies evaluating cost per additional vaccine administered found that they ranged from $49-75. Overall, fears about financial incentives decreasing COVID-19 vaccine uptake are not supported by the evidence. Financial incentives likely increase COVID-19 vaccine uptake. While these increases appear to be small, they may be meaningful across populations. Registration: PROSPERO, CRD42022316086 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022316086).


Subject(s)
COVID-19 , Motivation , Humans , COVID-19 Vaccines , COVID-19/prevention & control , Vaccination , Research Design
3.
BMC Psychiatry ; 23(1): 551, 2023 07 31.
Article in English | MEDLINE | ID: mdl-37525179

ABSTRACT

BACKGROUND: Cotard's Syndrome (CS) is a rare clinical entity where patients can report nihilistic, delusional beliefs that they are already dead. Curiously, while weight loss, dehydration, and metabolic derangements have been described as discussed above, a review of the literature revealed neither a single case of a severely underweight patient nor a serious metabolic complication such as Diabetic Ketoacidosis. Further, a search on PubMed revealed no articles discussing the co-occurrence of Cotard's Delusion and eating disorders or comorbid metabolic illnesses such as diabetes mellitus. In order to better examine the association between Cotard's Delusion and comorbid eating disorders and metabolic illness, we will present and discuss a case where Cotard's delusion led to a severe metabolic outcome of DKA and a BMI of 15. CASE PRESENTATION: Mr. B is a 19 year old transgender man admitted to the hospital due to diabetic ketoacidosis secondary to Type 1 Diabetes Mellitus. Mr. B had a history of Obsessive-Compulsive Disorder, Major Depressive Disorder, and Post-Traumatic Stress Disorder. The primary pediatric team discovered that Mr. B had not been using his insulin appropriately and was severely underweight, and they believed this could be due to his underlying mental illness. The psychiatric consultation/liaison service found that Mr. B was suffering from Cotard's delusion leading him to be noncompliant with his insulin due to a belief that he was already dead. Cotard's delusion had in this case led to a severe metabolic outcome of DKA and a BMI of 15. CONCLUSIONS: This case provides clinical insight into the interactions of eating disorders and Cotard's delusion as well as the potential medical complications when Cotard's delusion is co-morbid with medical conditions such as Diabetes Mellitus. We recommend that clinicians routinely screen patients for Cotard's delusion and assess whether the presence of which could exacerbate any underlying medical illness. This includes clinicians taking special care in assessing patient's caloric and fluid intake as well as their adherence to medications both psychiatric and medical. Further research could be conducted to explore the potential overlap of Cotard's delusion and eating disorder phenomenology.


Subject(s)
Depressive Disorder, Major , Diabetes Mellitus , Diabetic Ketoacidosis , Humans , Male , Child , Young Adult , Adult , Delusions/etiology , Insulin , Diabetic Ketoacidosis/complications , Body Mass Index , Thinness , Syndrome
7.
J Comput Chem ; 42(11): 761-770, 2021 Apr 30.
Article in English | MEDLINE | ID: mdl-33617652

ABSTRACT

Minimum-energy path (MEP) calculations, such as those typified by the nudged elastic band method, require input of reactant and product molecular configurations at initialization. In the case of reactions involving more than one molecule, generating initial reactant and product configurations requires careful consideration of the relative position and orientations of the reactive molecules in order to ensure that the resulting MEP calculation proceeds without converging on an alternative reaction-path, and without requiring excessive numbers of optimization iterations; as such, this initial system set-up is most commonly performed "by hand," with an expert user arranging reactive molecules in space to ensure that the following MEP calculation runs smoothly. In this Article, we introduce a simple preconditioning scheme which replaces this labor-intensive, human-knowledge-based step with an automated deterministic computational scheme. In our approach, initial reactant and product configurations are generated such that steric hindrance between reactive molecules is minimized in the reactant and product configurations, while also simultaneously requiring minimal structural differences between the reactants and products. The method is demonstrated using a benchmark test-set of >3400 organic molecular reactions, where comparison of the reactant/product configurations generated using our approach compare very well to initial configurations which were generated on an ad hoc basis.

8.
Econ Lett ; 209: 110097, 2021 Dec.
Article in English | MEDLINE | ID: mdl-35153345

ABSTRACT

This research evaluates the effects of the twelve statewide vaccine lottery schemes that were announced as of June 7, 2021 on state vaccination rates. We construct a dataset that matches information on the timing and location of these lotteries with daily, county-level data from the U.S. Centers for Disease Control (CDC) on the cumulative number of people who have received at least one dose of an emergency-authorized Covid-19 vaccine. We find that 10 of the 12 statewide lotteries studied (i.e., all but Arkansas and California) generated a positive, statistically significant, and economically meaningful impact on vaccine uptake after thirty days. On average, the cost per marginal vaccination across these programs was approximately $55.

10.
Cogn Process ; 21(1): 77-93, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31489521

ABSTRACT

During interceptive motor tasks, experts demonstrate distinct visual search behavior (from novices) that is reflective of information extraction from optimal environmental cues, which subsequently aids anticipatory movements. While some forms of visual training have been employed in sport, over-speed video training is rarely applied to perceptual-cognitive sport contexts. The purpose of the present study was to determine whether over-speed video training can enhance visual information processing and augment visual behavior for a pitch-recognition task. Twelve collegiate softball players were recruited for the study. A between-subjects, repeated measures design was implemented to assess changes in participants' pitch recognition on a video-based occlusion task after one of two training interventions: (A) over-speed video training (n = 6) or (B) regular video training (n = 6). Both training interventions required individuals to view 400 videos of different pitches over the span of 10 days. The over-speed group viewed the videos at gradually increasing video speeds (+ 0.05 × each day). Performance (i.e., identifying pitch type and location), quiet-eye duration (i.e., total QE, QE-early and QE-late) and cortical activation (i.e., alpha wave activity/asymmetry; F3/F4 and P7/P8) were measured during the pitch-recognition tasks. Results showed significant performance improvements across groups, but no differences between groups. Both interventions were associated with a reduction in alpha wave activity for P8, an increase in alpha activity for F3, and a significant increase in QE-late. An increase in QE-late was associated with a decrease in P7/P8 alpha asymmetry and improvements in pitch-type recognition. Consistent with the extant literature, our results support the importance of a later QE offset for successful performance on perceptual tasks, potentially extending to perceputal-motor tasks. Although participants in the over-speed condition did not experience significantly larger improvements in performance than controls, this study highlights the association between QE and brain activity reflective of expertise.


Subject(s)
Athletic Performance/education , Athletic Performance/psychology , Baseball/education , Baseball/psychology , Reaction Time/physiology , Video Recording , Visual Perception/physiology , Adolescent , Alpha Rhythm , Cerebral Cortex/physiology , Cues , Electroencephalography , Female , Humans , Psychomotor Performance/physiology , Recognition, Psychology , Young Adult
11.
Am J Law Med ; 46(2-3): 311-324, 2020 05.
Article in English | MEDLINE | ID: mdl-32659194

ABSTRACT

Telehealth continues to experience substantial investment, innovation, and unprecedented growth. However, telehealth has been slow to transform healthcare. Recent developments in telehealth technologies suggest great potential for chronic care management, mental health services, and care delivery in the home-all of which should be particularly impactful for an aging population with physical and cognitive limitations. While this alignment of technological capacity and market demand is promising, legal barriers remain for telehealth operators to scale up across large geographic areas. To better understand how federal and state law can be reformed to enable greater telehealth utilization, we review and extract lessons from (1) establishment of a healthcare relationship, (2) state licensure laws, and (3) reimbursement. We analyze these areas because of the legal ambiguities or inconsistencies they raise depending on the state, which seem to be hampering telehealth growth without necessarily improving quality of care. We propose several solutions for a more unified approach to telehealth regulation that incorporate core bioethics principles of doctor-patient relationship, competence, patient autonomy, as well as population-wide questions of resource allocation and access. Lawmakers should clarify that healthcare relationships may be established outside of in-person meetings, align licensure laws via an interstate compact or federal preemption, and expand Centers for Medicare and Medicaid plans to reimburse telehealth delivery in the home.


Subject(s)
Aging , Government Regulation , Insurance, Health, Reimbursement , Licensure/legislation & jurisprudence , Physician-Patient Relations , Telemedicine/economics , Telemedicine/legislation & jurisprudence , Aged , Centers for Medicare and Medicaid Services, U.S. , Federal Government , Humans , State Government , United States
13.
J Comput Chem ; 40(6): 794-810, 2019 Mar 05.
Article in English | MEDLINE | ID: mdl-30593705

ABSTRACT

The presence of nonadiabatic effects during the interaction of small molecules with metals has been observed experimentally for the last decades. Specially remarkable are the effects found for NO/Au, where experiments have suggested the presence of very strong vibronic coupling during the molecular scattering. However, the accurate inclusion of the nonadiabatic effects in periodic boundary conditions (PBC) theoretical methods remain an unapproachable challenge. Here, aiming to give some theoretical insight to the strong vibronic coupling, we have adopted a pragmatic point of view, taking use of an auxiliary simplified system, NO/Au3 . We show the importance of nonadiabatic coupling, during the scattering of NO from a Au3 cluster, using a diabatic representation of 12 electronic states of the system, including a few charge-transfer states. Our diabatic representation is obtained by rotating the orbital and configuration interaction (CI) vectors of a restricted active space (RAS) wavefunction. We present a strategy for extracting the best effective manifold of states relevant to the system, below some prescribed energy, directly from the RAS CI vectors. This scheme is able to disentangle a large dense manifold of adiabatic states with strong coupling and crossings. This approach is also shown to work for multireference configuration interaction (MRCI). By performing quantum propagations, we observed an increase in vibrational redistribution with increasing initial vibrational or translational energies. We suggest that these nonadiabatic effects should also be present at smaller energies in larger clusters. © 2018 Wiley Periodicals, Inc.

14.
Faraday Discuss ; 216(0): 476-493, 2019 07 11.
Article in English | MEDLINE | ID: mdl-31016309

ABSTRACT

The ground-up design of new molecular sunscreens, with improved photostability, absorbance and spectral coverage, stands as a challenge to fundamental chemical science. Correlating sunscreen molecular structure and function requires detailed insight into the relaxation pathways available following photoexcitation; however, the complex coupled electron/nuclear dynamics in these systems stands as a tough challenge to computational chemistry. To address this challenge, we have recently developed efficient and accurate simulation methods to model non-adiabatic dynamics of general molecular systems as a route to correlating photoinduced dynamics and potential sunscreen activity. Our approach, combining the multi-configuration time-dependent Hartree (MCTDH) method with PESs generated using machine-learning, represents a new "on-the-fly" strategy for accurate wavefunction propagation, with the potential to provide a new "black box" strategy for interrogating ultrafast dynamics in general photoinduced energy transport processes. Here, we illustrate our attempts to apply this methodology to study the ultrafast photochemistry of four compounds derived from mycosporine-like amino acids (MAAs), compounds which are believed to act as microbial sunscreens in micro-organisms such as algae. Specifically, we investigate how the choice of active vibrational space and diabatic electronic states in MCTDH strongly influences the predictions of ultrafast dynamic relaxation in representative MAAs. Our results serve to demonstrate that "on-the-fly" quantum dynamics using MCTDH is increasingly viable, but important barriers relating to coordinate choices and diabatisation remain.


Subject(s)
Amino Acids/chemistry , Quantum Theory , Sunscreening Agents/chemistry , Machine Learning , Molecular Structure
15.
J Phys Chem A ; 123(15): 3407-3417, 2019 Apr 18.
Article in English | MEDLINE | ID: mdl-30900894

ABSTRACT

Proposing and testing mechanistic hypotheses stands as one of the key applications of contemporary computational chemistry. In the majority of computational mechanistic analyses, the individual elementary steps leading from reactants to products are proposed by the user, based on learned chemical knowledge, intuition, or comparison to an existing well-characterized mechanism for a closely related chemical reaction. However, the prerequisite of prior chemical knowledge is a barrier to automated (or "black box") mechanistic generation and assessment, and it may simultaneously preclude mechanistic proposals that lie outside the "standard" chemical reaction set. In this Article, we propose a simple random-walk algorithm that searches for the set of elementary chemical reactions that transform defined reactant structures into target products. Our approach operates exclusively in the space of molecular connectivity matrices, seeking the set of chemically sensible bonding changes that link connectivity matrices for input reactant and product structures. We subsequently illustrate how atomic coordinates for each elementary reaction can be generated under the action of a graph-restraining potential, prior to further analysis by quantum chemical calculations. Our approach is successfully demonstrated for carbon monoxide oxidation, the water-gas shift reaction, and n-hexane aromatization, all catalyzed by Pt nanoparticles.

16.
Am J Bioeth ; 24(7): 100-101, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38913465
17.
Chemphyschem ; 19(19): 2472-2479, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-29923663

ABSTRACT

The ratio of NMR relaxation time constants T 1 / T 2 provides a non-destructive indication of the relative surface affinities exhibited by adsorbates within liquid-saturated mesoporous catalysts. In the present work we provide supporting evidence for the existence of a quantitative relationship between such measurements and adsorption energetics. As a prototypical example with relevance to green chemical processes we examine and contrast the relaxation characteristics of primary alcohols and cyclohexane within an industrial silica catalyst support. T 1 / T 2 values obtained at intermediate magnetic field strength are in good agreement with DFT adsorption energy calculations performed on single molecules interacting with an idealised silica surface. Our results demonstrate the remarkable ability of this metric to quantify surface affinities within systems of relevance to liquid-phase heterogeneous catalysis, and highlight NMR relaxation as a powerful method for the determination of adsorption phenomena within mesoporous solids.

18.
J Chem Phys ; 148(10): 102316, 2018 Mar 14.
Article in English | MEDLINE | ID: mdl-29544325

ABSTRACT

We present an approximation to the thermal symmetric form of the quantum time-correlation function in the standard position path-integral representation. By transforming to a sum-and-difference position representation and then Taylor-expanding the potential energy surface of the system to second order, the resulting expression provides a harmonic weighting function that approximately recovers the contribution of the phase to the time-correlation function. This method is readily implemented in a Monte Carlo sampling scheme and provides exact results for harmonic potentials (for both linear and non-linear operators) and near-quantitative results for anharmonic systems for low temperatures and times that are likely to be relevant to condensed phase experiments. This article focuses on one-dimensional examples to provide insights into convergence and sampling properties, and we also discuss how this approximation method may be extended to many-dimensional systems.

19.
J Am Pharm Assoc (2003) ; 58(3): 296-302, 2018.
Article in English | MEDLINE | ID: mdl-29402662

ABSTRACT

OBJECTIVES: To use a pharmacist-managed short-acting beta agonist (SABA) service (1) to determine the patient's rationale for SABA refill requests, (2) to assess adherence to current controller therapy and current level of disease control, and (3) to characterize the pharmacist's recommendations made in response to a patient's SABA refill request. SETTING: An academic-based general pediatric clinic. PRACTICE DESCRIPTION: SABA overuse is a marker of increased morbidity and mortality in children with asthma. This article describes a pharmacist-managed SABA refill telephone service. PRACTICE INNOVATION: The pediatric ambulatory care pharmacy team assessed and authorized (or denied) all SABA refill requests, provided education, and facilitated appropriate follow-up using a telephone service. INTERVENTIONS: Upon receiving a patient-requested SABA refill, the pharmacist identified the reason for the SABA request, assessed asthma control, and determined adherence to daily controllers or spacer use, if applicable. Education was also provided. Data obtained were used to determine SABA refill approval. EVALUATION: Primary reasons for SABA refill request were for (1) current symptom management and (2) no refills remaining in the absence of symptoms. Forty-two (50%) SABA refill requests were eligible for refill per the clinic algorithm, yet 70% actually received a refill after assessment by the pharmacist. Asthma control was assessed as 26% well controlled, 38% not well controlled, and 36% very poorly controlled. Forty-eight percent of patients prescribed daily controller medications were deemed adherent. Spacers were used in 43 of 76 (56%) patients using metered dose inhalers. Education was provided to 82% of caregivers. Pharmacists facilitated asthma follow-up visits in 41 of 84 (49%) patients contacted, and 61% of those appointments were kept. CONCLUSIONS: Pharmacist management of a SABA refill telephone service provides an additional means for delivery of asthma education, facilitates follow-up asthma care, helps to identify patients at risk for increased morbidity and mortality due to the overuse of SABAs, and provides another mechanism for medication refills.


Subject(s)
Adrenergic beta-Agonists/administration & dosage , Pharmaceutical Services/organization & administration , Pharmacists/organization & administration , Ambulatory Care Facilities/organization & administration , Asthma/drug therapy , Child , Drug Prescriptions , Female , Humans , Male , Pharmacies/organization & administration , Primary Health Care/organization & administration
20.
JAMA ; 329(5): 365-366, 2023 02 07.
Article in English | MEDLINE | ID: mdl-36622690

ABSTRACT

This Viewpoint discusses how some pulse oximeters can provide incorrect oxygen saturation data for dark-skinned patients compared with light-skinned patients, describes the reasons that biased oximeters remained in use, and highlights why a rule recently proposed by the US Department of Health and Human Services may bring about needed change in the use of pulse oximetry for patients with dark skin.


Subject(s)
Human Rights , Oximetry , Social Discrimination , Oximetry/instrumentation , Oximetry/standards , Social Discrimination/legislation & jurisprudence , Social Discrimination/prevention & control , United States , Federal Government , Human Rights/legislation & jurisprudence , Human Rights/standards
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