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1.
J Am Chem Soc ; 146(23): 15688-15692, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38815061

RESUMO

We report the direct and accurate spectroscopic quantification of the inverted singlet-triplet gap in 1,3,4,6,9b-pentaazaphenalene. This measurement is achieved by directly probing the lowest singlet and triplet states via high-resolution cryogenic anion photoelectron spectroscopy. The assignment of the first excited singlet state is confirmed by visible absorption spectroscopy in an argon matrix at 20 K. Our measurements yield an inverted singlet-triplet gap with ΔEST= -0.047(7) eV. The accurate quantification of the singlet-triplet gap presented here allows for direct evaluation of various computational electronic structure methods and highlights the critical importance of the proper description of the double excitation character of these electronic states. Overall, this study validates the idea that despite Hund's multiplicity rule, useful organic chromophores can have inherently inverted singlet-triplet gaps.

2.
Lancet ; 401(10394): 2138-2147, 2023 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-37321235

RESUMO

BACKGROUND: VLA1553 is a live-attenuated vaccine candidate for active immunisation and prevention of disease caused by chikungunya virus. We report safety and immunogenicity data up to day 180 after vaccination with VLA1553. METHODS: This double-blind, multicentre, randomised, phase 3 trial was done in 43 professional vaccine trial sites in the USA. Eligible participants were healthy volunteers aged 18 years and older. Patients were excluded if they had history of chikungunya virus infection or immune-mediated or chronic arthritis or arthralgia, known or suspected defect of the immune system, any inactivated vaccine received within 2 weeks before vaccination with VLA1553, or any live vaccine received within 4 weeks before vaccination with VLA1553. Participants were randomised (3:1) to receive VLA1553 or placebo. The primary endpoint was the proportion of baseline negative participants with a seroprotective chikungunya virus antibody level defined as 50% plaque reduction in a micro plaque reduction neutralisation test (µPRNT) with a µPRNT50 titre of at least 150, 28 days after vaccination. The safety analysis included all individuals who received vaccination. Immunogenicity analyses were done in a subset of participants at 12 pre-selected study sites. These participants were required to have no major protocol deviations to be included in the per-protocol population for immunogenicity analyses. This trial is registered at ClinicalTrials.gov, NCT04546724. FINDINGS: Between Sept 17, 2020 and April 10, 2021, 6100 people were screened for eligibility. 1972 people were excluded and 4128 participants were enrolled and randomised (3093 to VLA1553 and 1035 to placebo). 358 participants in the VLA1553 group and 133 participants in the placebo group discontinued before trial end. The per-protocol population for immunogenicity analysis comprised 362 participants (266 in the VLA1553 group and 96 in the placebo group). After a single vaccination, VLA1553 induced seroprotective chikungunya virus neutralising antibody levels in 263 (98·9%) of 266 participants in the VLA1553 group (95% CI 96·7-99·8; p<0·0001) 28 days post-vaccination, independent of age. VLA1553 was generally safe with an adverse event profile similar to other licensed vaccines and equally well tolerated in younger and older adults. Serious adverse events were reported in 46 (1·5%) of 3082 participants exposed to VLA1553 and eight (0·8%) of 1033 participants in the placebo arm. Only two serious adverse events were considered related to VLA1553 treatment (one mild myalgia and one syndrome of inappropriate antidiuretic hormone secretion). Both participants recovered fully. INTERPRETATION: The strong immune response and the generation of seroprotective titres in almost all vaccinated participants suggests that VLA1553 is an excellent candidate for the prevention of disease caused by chikungunya virus. FUNDING: Valneva, Coalition for Epidemic Preparedness Innovation, and EU Horizon 2020.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Humanos , Idoso , Febre de Chikungunya/prevenção & controle , Vacinas Atenuadas , Anticorpos Antivirais , Vacinação , Método Duplo-Cego
3.
J Child Psychol Psychiatry ; 65(3): 328-339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37257941

RESUMO

BACKGROUND: Across several sites in the United States, we examined whether kindergarten conduct problems among mostly population-representative samples of children were associated with increased criminal and related (criminal + lost offender productivity + victim; described as criminal + victim hereafter) costs across adolescence and adulthood, as well as government and medical services costs in adulthood. METHODS: Participants (N = 1,339) were from two multisite longitudinal studies: Fast Track (n = 754) and the Child Development Project (n = 585). Parents and teachers reported on kindergarten conduct problems, administrative and national database records yielded indexes of criminal offending, and participants self-reported their government and medical service use. Outcomes were assigned costs, and significant associations were adjusted for inflation to determine USD 2020 costs. RESULTS: A 1SD increase in kindergarten conduct problems was associated with a $21,934 increase in adolescent criminal + victim costs, a $63,998 increase in adult criminal + victim costs, a $12,753 increase in medical services costs, and a $146,279 increase in total costs. In the male sample, a 1SD increase in kindergarten conduct problems was associated with a $28,530 increase in adolescent criminal + victim costs, a $58,872 increase in adult criminal + victim costs, and a $144,140 increase in total costs. In the female sample, a 1SD increase in kindergarten conduct problems was associated with a $15,481 increase in adolescent criminal + victim costs, a $62,916 increase in adult criminal + victim costs, a $24,105 increase in medical services costs, and a $144,823 increase in total costs. CONCLUSIONS: This investigation provides evidence of the long-term costs associated with early-starting conduct problems, which is important information that can be used by policymakers to support research and programs investing in a strong start for children.


Assuntos
Transtorno da Conduta , Comportamento Problema , Adulto , Criança , Humanos , Masculino , Adolescente , Feminino , Estados Unidos/epidemiologia , Transtorno da Conduta/epidemiologia , Estudos Longitudinais , Autorrelato , Escolaridade
4.
J Phys Chem A ; 128(8): 1427-1437, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38354365

RESUMO

The gas-phase rotational spectrum of 1-cyano-2-methylenecyclopropane (C1, C5H5N), an isomer of pyridine, is presented for the first time, covering the range from 235 to 500 GHz. Over 3600 a-, b-, and c-type transitions for the ground vibrational state have been assigned, measured, and least-squares fit to partial-octic A- and S-reduced distorted-rotor Hamiltonians with low statistical uncertainty (σfit = 42 kHz). Transitions for the two lowest-energy fundamental states (ν27 and ν26) and the lowest-energy overtone (2ν27) have been similarly measured, assigned, and least-squares fit to single-state Hamiltonians. Computed vibration-rotation interaction constants (B0-Bv) using the B3LYP and MP2 levels of theory are compared with the corresponding experimental values. Based upon our preliminary analysis, the next few vibrationally excited states form one or more complex polyads of interacting states via Coriolis and anharmonic coupling. The spectroscopic constants and transition frequencies presented here form the foundation for both future laboratory spectroscopy and astronomical searches for 1-cyano-2-methylenecyclopropane.

5.
J Phys Chem A ; 128(8): 1417-1426, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38329215

RESUMO

Broad-band ultraviolet photolysis (λ > 200 nm) of (cyanomethylene)cyclopropane (5) in an argon matrix at 20 K generates 1-cyano-2-methylenecyclopropane (7), a previously unknown compound. This product was initially identified by comparison of its infrared spectrum to that predicted by an anharmonic MP2/6-311+G(2d,p) calculation. This assignment was unambiguously confirmed by the synthesis of 1-cyano-2-methylenecyclopropane (7) and observation of its authentic infrared spectrum, which proved identical to that of the observed photoproduct. We investigated the singlet and triplet potential energy surfaces associated with this isomerization process using density functional theory and multireference calculations. The observed rearrangement of compound 5 to compound 7 is computed to be endothermic (3.3 kcal/mol). We were unable to observe the reverse reaction (7 → 5) under the photochemical conditions.

6.
J Phys Chem A ; 128(1): 191-203, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38153243

RESUMO

The millimeter-wave rotational spectrum of 1-oxaspiro[2.5]octa-4,7-dien-6-one (1) was collected from 235 to 360 GHz. With the rotational spectrum of this compound available for the first time, more than 5500 a- and c-type transitions were observed and assigned for the vibrational ground state. These transitions were least-squares fit to S- and A-reduced, sextic distorted-rotor Hamiltonians in the Ir representation (σfit = 37 kHz). Additionally, transitions of four fundamental states (ν22, ν21, ν39, and ν38), four overtone states (2ν22, 3ν22, 4ν22, and 5ν22), and two combination states (ν22 + ν21 and ν22 + ν39) were measured, assigned, and least-squares fit to single-state, S- and A-reduced, sextic distorted-rotor Hamiltonians in the Ir representation (σfit < 42 kHz). The computed vibration-rotation interaction constants (B0 - Bv) (MP2 and B3LYP/6-311+G(2d,p)) were compared to their corresponding experimental values, showing excellent agreement for all fundamental states. Based on the intensities of the transitions from six members of the v ν22 series, the fundamental frequency of ν22 was determined to be 79.0 (2.1) cm-1.

7.
J Phys Chem A ; 128(33): 6927-6942, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39119943

RESUMO

A combined analysis of millimeter-wave (70-700 GHz) and rotationally resolved infrared (400-1200 cm-1) spectra of the ground state and seven fundamental vibrational modes of 1H-1,2,4-triazole is reported. While the lowest-energy vibrationally excited state (ν18) is well-treated using a single-state distorted-rotor Hamiltonian, the second (ν17) and third (ν16) vibrationally excited states are involved in strong c-type Coriolis coupling and require an appropriate two-state Hamiltonian. The oblate nature of 1H-1,2,4-triazole is sufficiently close to the oblate symmetric-top limit that the analysis requires the use of A-reduced, sextic centrifugally distorted-rotor Hamiltonian models in the Ir representation in order to achieve low σfit values. The coupling between ν17 (A″) and ν16 (A″) resulted in many transitions with slightly perturbed frequencies, many highly displaced resonant intrastate transitions, and 165 nominal interstate transitions. Modeling the spectra of ν17 and ν16 required three c-axis Coriolis-coupling terms (Fab, FabJ, and FabK) to treat the interaction. Many of the nominal interstate transitions form clearly discernible Q-branch bands, comprising degenerate sets of a- and b-type transitions. The rotational spectra of four higher-energy vibrationally excited states (ν15, ν14, ν13, and ν12), which form a complex polyad involving Coriolis and anharmonic coupling interactions, were analyzed by single-state models, thus producing only effective spectroscopic constants. Inclusion of rotationally resolved infrared transitions enabled the accurate and precise determination of vibrational band origins for the four lowest-energy fundamental states: ν18 = 542.601 824 3 (28) cm-1, ν17 = 665.183 128 5 (43) cm-1, ν16 = 682.256 910 5 (43) cm-1, and ν15 = 847.557 400 (11) cm-1.

8.
J Phys Chem A ; 128(29): 6084-6097, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916202

RESUMO

The rotational spectrum of 3-furonitrile has been collected from 85 to 500 GHz, spanning the most intense rotational transitions observable at room temperature. The large dipole moment imparted by the nitrile substituent confers substantial intensity to the rotational spectrum, enabling the observation of over 5600 new rotational transitions. Combined with previously published transitions, the available data set was least-squares fit to partial-octic, distorted-rotor A- and S-reduced Hamiltonian models with low statistical uncertainty (σfit < 0.031 MHz) for the ground vibrational state. Similar to its isomer 2-furonitrile, the two lowest-energy vibrationally excited states of 3-furonitrile (ν17, ν24), which correspond to the in-plane and out-of-plane nitrile bending vibrations, form an a- and b-axis Coriolis-coupled dyad. Rotationally resolved infrared transitions (30-600 cm-1) and over 4200 pure rotational transitions for both ν17 and ν24 were fit to a partial-octic, Coriolis-coupled, two-state Hamiltonian with low statistical uncertainty (σfit rot < 0.045 MHz, σfit IR < 6.1 MHz). The least-squares fitting of these vibrationally excited states provides their accurate and precise vibrational frequencies (ν17 = 168.193 164 8 (67) cm-1 and ν24 = 169.635 831 5 (77) cm-1) and seven Coriolis-coupling terms (Ga, GaJ, GaK, Fbc, FbcK, Gb, and Fac). The two fundamental states exhibit a notably small energy gap (1.442 667 (10) cm-1) and an inversion of the relative energies of ν17 and ν24 compared to those of the isomer 2-furonitrile. The rotational frequencies and spectroscopic constants of 3-furonitrile that we present herein provide a sufficient basis for conducting radioastronomical searches for this molecule across the majority of the frequency range available to current radiotelescopes.

9.
J Chem Phys ; 160(19)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38747434

RESUMO

The gas-phase rotational spectrum from 8 to 750 GHz and the high-resolution infrared (IR) spectrum of pyridazine (o-C4H4N2) have been analyzed for the ground and four lowest-energy vibrationally excited states. A combined global fit of the rotational and IR data has been obtained using a sextic, centrifugally distorted-rotor Hamiltonian with Coriolis coupling between appropriate states. Coriolis coupling has been addressed in the two lowest-energy coupled dyads (ν16, ν13 and ν24, ν9). Utilizing the Coriolis coupling between the vibrational states of each dyad and the analysis of the IR spectrum for ν16 and ν9, we have determined precise band origins for each of these fundamental states: ν16 (B1) = 361.213 292 7 (17) cm-1, ν13 (A2) = 361.284 082 4 (17) cm-1, ν24 (B2) = 618.969 096 (26) cm-1, and ν9 (A1) = 664.723 378 4 (27) cm-1. Notably, the energy separation in the ν16-ν13 Coriolis-coupled dyad is one of the smallest spectroscopically measured energy separations between vibrational states: 2122.222 (72) MHz or 0.070 789 7 (24) cm-1. Despite ν13 being IR inactive and ν24 having an impractically low-intensity IR intensity, the band origins of all four vibrational states were measured, showcasing the power of combining the data provided by millimeter-wave and high-resolution IR spectra. Additionally, the spectra of pyridazine-dx isotopologues generated for a previous semi-experimental equilibrium structure (reSE) determination allowed us to analyze the two lowest-energy vibrational states of pyridazine for all nine pyridazine-dx isotopologues. Coriolis-coupling terms have been measured for analogous vibrational states across seven isotopologues, both enabling their comparison and providing a new benchmark for computational chemistry.

10.
Dev Psychopathol ; : 1-14, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38654407

RESUMO

This study aimed to parse between-person heterogeneity in growth of impulsivity across childhood and adolescence among participants enrolled in five childhood preventive intervention trials targeting conduct problems. In addition, we aimed to test profile membership in relation to adult psychopathologies. Measurement items representing impulsive behavior across grades 2, 4, 5, 7, 8, and 10, and aggression, substance use, suicidal ideation/attempts, and anxiety/depression in adulthood were integrated from the five trials (N = 4,975). We applied latent class growth analysis to this sample, as well as samples separated into nonintervention (n = 2,492) and intervention (n = 2,483) participants. Across all samples, profiles were characterized by high, moderate, low, and low-increasing impulsive levels. Regarding adult outcomes, in all samples, the high, moderate, and low profiles endorsed greater levels of aggression compared to the low-increasing profile. There were nuanced differences across samples and profiles on suicidal ideation/attempts and anxiety/depression. Across samples, there were no significant differences between profiles on substance use. Overall, our study helps to inform understanding of the developmental course and prognosis of impulsivity, as well as adding to collaborative efforts linking data across multiple studies to better inform understanding of developmental processes.

11.
J Am Chem Soc ; 145(40): 21785-21797, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37774420

RESUMO

Recent advances in gas-phase structure determination afford outstanding agreement between the CCSD(T)/cc-pCVTZ-corrected semi-experimental (reSE) equilibrium structures and their corresponding best theoretical estimates (BTEs) of the equilibrium structures (re) based upon corrections to the CCSD(T)/cc-pCV5Z geometries for the aromatic heterocycles pyrimidine and pyridazine. Herein, that same analysis is extended to the fundamental aromatic molecule benzene, using published experimental spectroscopic data for a total of 11 available isotopologues. The incorporation of rotational constants from all of these isotopologues and CCSD(T) corrections to address the impacts of both the vibration-rotation interaction and electron-mass distribution results in a highly precise and accurate reSE structure. The CCSD(T)/cc-pCV5Z optimized geometry has been further corrected to address a finite basis set, untreated electron correlation, relativistic effects, and a breakdown of the Born-Oppenheimer approximation. This analysis achieves outstanding agreement between the re (BTE) and reSE structural parameters of benzene to a highly satisfying level (0.0001 Å), an agreement that surpasses our recently published structures of the aforementioned nitrogen-substituted benzene analogues. The D6h geometry of benzene is now known to an unprecedented precision: RC-C = 1.3913 (1) Å and RC-H = 1.0809 (1) Å. The mutual agreement between theory and experiment presented in this work validates both, substantially resolving all discrepancies between the reSE and theoretical re structures available in the literature.

12.
J Child Psychol Psychiatry ; 64(5): 820-830, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35705512

RESUMO

BACKGROUND: Maladaptive family environments harm child development and are passed across generations. Childhood interventions may break this intergenerational cycle by improving the family environments children form as adults. The present study investigates this hypothesis by examining follow-up data collected 18 years after the end of the childhood Fast Track intervention designed to prevent externalizing problems. METHODS: We examined whether Fast Track assignment from grades 1 to 10 prevented the emergence of maladaptive family environments at age 34. A total of 400 (n = 206 in intervention condition, n = 194 controls) Fast Track participants who were parents at age 34 were surveyed about 11 aspects of their current family environment. The hypotheses and analytic plan were preregistered at https://osf.io/dz9t5 and the Fast Track trial was registered at clinicaltrials.gov (NCT01653535). RESULTS: Multiple group linear regression models revealed that mothers who participated in the Fast Track intervention as children had lower depression symptoms, alcohol problems, drug problems, corporal punishment use, and food insecurity compared to control group mothers. All effects were modest in magnitude. However, for these same mothers, the Fast Track intervention had no effect on cannabis problems, experiences of romantic partner violence, or maternal use of physical aggression or warmth with their children. Additionally, mothers in the Fast Track intervention group reported higher levels of family chaos than those in the control group, but this effect may be a byproduct of the higher number of children per household in the intervention group. No intervention effects were found for fathers who participated in the Fast Track intervention as children. CONCLUSIONS: Childhood assignment to Fast Track has some beneficial effects for girls, but not boys, on the family environments these individuals formed as adults 18 years later.


Assuntos
Mães , Pais , Criança , Feminino , Adulto , Humanos , Agressão , Inquéritos e Questionários
13.
J Org Chem ; 88(23): 16176-16185, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37948641

RESUMO

Photolysis (λ > 613 nm) of 1-(3-thienyl)diazoethane (21) yields the s-E rotamer of triplet 1-(3-thienyl)ethylidene (3), as characterized by UV/vis and EPR spectroscopy. The s-Z rotamer of 3 was not observed. EPR and UV/vis signals attributed to carbene 3 decrease by approximately 50% upon standing in the dark for 68 h at 10 K. Although formally spin-forbidden, an intramolecular [1,2]-hydrogen shift in triplet carbene 3 to afford singlet s-E 3-vinylthiophene (8) is presumed to occur via quantum mechanical tunneling. The behavior of the CD3 analogue supports this interpretation. Photolysis (λ > 613 nm) of 1-(3-thienyl)diazoethane-d3 (21-d3) yields triplet 1-(3-thienyl)ethylidene-d3 (3-d3), as characterized by IR, UV/vis, and EPR spectroscopy. No change in the signal intensity of EPR and UV/vis signals of triplet 3-d3 is observed upon standing in the dark for 68 h at 10 K. In a series of 2-substituted thienyl derivatives, irradiation of 1-(2-thienyl)diazoethane (22), 1-(2-thienyl)diazoethane-d3 (22-d3), or (3-methyl-2-thienyl)diazomethane (23) does not yield triplet carbene intermediates. Positioning and labeling of the methyl group proved to have a large effect on products observed for these species. 1-(2-Thienyl)diazoethane (22) yields the products of [1,2]-hydrogen migration, s-Z and s-E 2-vinylthiophene (7), while 22-d3 and 23 give products derived from opening of the thiophene ring.

14.
J Phys Chem A ; 127(19): 4277-4290, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37146283

RESUMO

We present computational studies of reaction pathways for alkyne/polyyne dimerization that represent plausible early steps in mechanisms for carbon condensation. A previous computational study of the ring coalescence and annealing model of C60 formation revealed that a 1,4-didehydrobenzocyclobutadiene intermediate (p-benzyne derivative) has little to no barrier to undergoing an unproductive retro-Bergman cyclization, which brings into question the relevance of that reaction pathway. The current study investigates an alternative model, which proceeds through an initial [4 + 2] cycloaddition instead of a [2 + 2] cycloaddition. In this pathway, the problematic intermediate is avoided, with the reaction proceeding via a (potentially) more kinetically stable tetradehydronaphthalene derivative. The computational studies of the [2 + 2] and [4 + 2] model systems, with increasing alkyne substitutions, reveal that the para-benzyne diradical of the [4 + 2] pathway has a significantly greater barrier to ring opening than the analogous intermediates of the [2 + 2] pathway and that alkyne substitution has little effect on this important barrier. These studies employ spin-flip, time-dependent density functional theory (SF-TDDFT) to provide suitable treatment of open-shell diradical intermediates.

15.
J Phys Chem A ; 127(8): 1909-1922, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36794985

RESUMO

The rotational spectrum of 2-furonitrile (2-cyanofuran) has been obtained from 140 to 750 GHz, capturing its most intense rotational transitions at ambient temperature. 2-Furonitrile is one of two isomeric cyano-substituted furan derivatives, both of which possess a substantial dipole moment due to the cyano group. The large dipole of 2-furonitrile allowed over 10 000 rotational transitions of its ground vibrational state to be observed and least-squares fit to partial octic, A- and S-reduced Hamiltonians with low statistical uncertainty (σfit = 40 kHz). The high-resolution infrared spectrum, obtained at the Canadian Light Source, allowed for accurate and precise determination of the band origins of its three lowest-energy fundamental modes (ν24, ν17, and ν23). Similar to other cyanoarenes, the first two fundamental modes (ν24, A″, and ν17, A', for 2-furonitrile) form an a- and b-axis Coriolis-coupled dyad. More than 7000 transitions from each of these fundamental states were fit to an octic A-reduced Hamiltonian (σfit = 48 kHz), and the combined spectroscopic analysis determines fundamental energies of 160.1645522 (26) cm-1 and 171.9436561 (25) cm-1 for ν24 and ν17, respectively. The least-squares fitting of this Coriolis-coupled dyad required 11 coupling terms, Ga, GaJ, GaK, GaJJ, GaKK, Fbc, FbcJ, FbcK, Gb, GbJ, and FacK. Using both the rotational and high-resolution infrared spectra, a preliminary least-squares fit was obtained for ν23, providing its band origin of 456.7912716 (57) cm-1. The transition frequencies and spectroscopic constants provided in this work, when combined with theoretical or experimental nuclear quadrupole coupling constants, will provide the foundation for future radioastronomical searches for 2-furonitrile across the frequency range of currently available radiotelescopes.

16.
J Chem Phys ; 158(24)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37352424

RESUMO

The millimeter-wave rotational spectrum of ketene (H2C=C=O) has been collected and analyzed from 130 to 750 GHz, providing highly precise spectroscopic constants from a sextic, S-reduced Hamiltonian in the Ir representation. The chemical synthesis of deuteriated samples allowed spectroscopic measurements of five previously unstudied ketene isotopologues. Combined with previous work, these data provide a new, highly precise, and accurate semi-experimental (reSE) structure for ketene from 32 independent moments of inertia. This reSE structure was determined with the experimental rotational constants of each available isotopologue, together with computed vibration-rotation interaction and electron-mass distribution corrections from coupled-cluster calculations with single, double, and perturbative triple excitations [CCSD(T)/cc-pCVTZ]. The 2σ uncertainties of the reSE parameters are ≤0.0007 Å and 0.014° for the bond distances and angle, respectively. Only S-reduced spectroscopic constants were used in the structure determination due to a breakdown in the A-reduction of the Hamiltonian for the highly prolate ketene species. All four reSE structural parameters agree with the "best theoretical estimate" (BTE) values, which are derived from a high-level computed re structure [CCSD(T)/cc-pCV6Z] with corrections for the use of a finite basis set, the incomplete treatment of electron correlation, relativistic effects, and the diagonal Born-Oppenheimer breakdown. In each case, the computed value of the geometric parameter lies within the statistical experimental uncertainty (2σ) of the corresponding semi-experimental coordinate. The discrepancies between the BTE structure and the reSE structure are 0.0003, 0.0000, and 0.0004 Å for rC-C, rC-H, and rC-O, respectively, and 0.009° for θC-C-H.


Assuntos
Etilenos , Teoria Quântica , Análise Espectral , Cetonas
17.
J Chem Phys ; 158(4): 044301, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36725515

RESUMO

In this work, we present the spectral analysis of 1H- and 2H-1,2,3-triazole vibrationally excited states alongside provisional and practical computational predictions of the excited-state quartic centrifugal distortion constants. The low-energy fundamental vibrational states of 1H-1,2,3-triazole and five of its deuteriated isotopologues ([1-2H]-, [4-2H]-, [5-2H]-, [4,5-2H]-, and [1,4,5-2H]-1H-1,2,3-triazole), as well as those of 2H-1,2,3-triazole and five of its deuteriated isotopologues ([2-2H]-, [4-2H]-, [2,4-2H]-, [4,5-2H]-, and [2,4,5-2H]-2H-1,2,3-triazole), are studied using millimeter-wave spectroscopy in the 130-375 GHz frequency region. The normal and [2-2H]-isotopologues of 2H-1,2,3-triazole are also analyzed using high-resolution infrared spectroscopy, determining the precise energies of three of their low-energy fundamental states. The resulting spectroscopic constants for each of the vibrationally excited states are reported for the first time. Coupled-cluster vibration-rotation interaction constants are compared with each of their experimentally determined values, often showing agreement within 500 kHz. Newly available coupled-cluster predictions of the excited-state quartic centrifugal distortion constants based on fourth-order vibrational perturbation theory are benchmarked using a large number of the 1,2,3-triazole tautomer isotopologues and vibrationally excited states studied.

18.
Dev Psychopathol ; 35(1): 274-289, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34009113

RESUMO

While phenotypically indistinguishable with respect to callousness, individuals with primary and secondary callous-unemotional (CU) traits may show different developmental outcomes. This research predominantly comprised cross-sectional studies of male participants with a focus on maladaptive correlates. Thus, the present study examined whether youth with primary and secondary CU traits identified in Grade 7 reported distinct maladaptive outcomes (internalizing, externalizing, and substance use problems; criminal offenses; and sexual and partner experiences) and adaptive outcomes (health and wellbeing, education, and employment) in adulthood at age 25. We also examined sex differences. Participants included the high-risk control and normative samples from the Fast Track project (N = 754, male = 58%, Black = 46%). Youth with secondary CU traits reported higher levels of adult internalizing and externalizing psychopathology, a greater number of sexual partners and risky sexual behavior, and a greater number of violent offenses, compared with individuals with primary CU traits and those with low CU and anxiety symptoms. Conversely, youth with primary CU traits and low symptoms had higher wellbeing and happiness scores than those with secondary CU traits. Finally, there was differentiation on outcomes between female primary and secondary CU variants and male primary and secondary CU variants.


Assuntos
Transtorno da Conduta , Adulto , Humanos , Masculino , Adolescente , Feminino , Transtorno da Conduta/psicologia , Estudos Transversais , Ansiedade , Agressão/psicologia , Emoções
19.
Dev Psychopathol ; 35(2): 730-748, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35074036

RESUMO

Current conceptualizations of oppositional defiant disorder (ODD) place the symptoms of this disorder within three separate but related dimensions (i.e., angry/irritable mood, argumentative/defiant behavior, vindictiveness). Variable-centered models of these dimensions have yielded discrepant findings, limiting their clinical utility. The current study utilized person-centered latent class analysis based on self and parent report of ODD symptomatology from a community-based cohort study of 521 adolescents. We tested for sex, race, and age differences in the identified classes and investigated their ability to predict later symptoms of depression and conduct disorder (CD). Diagnostic information regarding ODD, depression, and CD were collected annually from adolescents (grades 6-9; 51.9% male; 48.7% White, 28.2% Black, 18.5% Asian) and a parent. Results provided evidence for three classes of ODD (high, medium, and low endorsement of symptoms), which demonstrated important developmental differences across time. Based on self-report, Black adolescents were more likely to be in the high and medium classes, while according to parent report, White adolescents were more likely to be in the high and medium classes. Membership in the high and medium classes predicted later increases in symptoms of depression and CD, with the high class showing the greatest risk for later psychopathology.


Assuntos
Transtornos de Deficit da Atenção e do Comportamento Disruptivo , Transtorno da Conduta , Humanos , Masculino , Adolescente , Feminino , Estudos de Coortes , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico , Transtorno da Conduta/diagnóstico , Psicopatologia , Humor Irritável
20.
Dev Psychopathol ; 35(4): 2028-2043, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35957585

RESUMO

This study examined whether a key set of adolescent and early adulthood risk factors predicts problematic alcohol, cannabis, and other substance use in established adulthood. Two independent samples from the Child Development Project (CDP; n = 585; 48% girls; 81% White, 17% Black, 2% other race/ethnicity) and Fast Track (FT; n = 463; 45% girls; 52% White, 43% Black, 5% other race/ethnicity) were recruited in childhood and followed through age 34 (CDP) or 32 (FT). Predictors of substance use were assessed in adolescence based on adolescent and parent reports and in early adulthood based on adult self-reports. Adults reported their own problematic substance use in established adulthood. In both samples, more risk factors from adolescence and early adulthood predicted problematic alcohol use in established adulthood (compared to problematic cannabis use and other substance use). Externalizing behaviors and prior substance use in early adulthood were consistent predictors of problematic alcohol and cannabis misuse in established adulthood across samples; other predictors were specific to the sample and type of substance misuse. Prevention efforts might benefit from tailoring to address risk factors for specific substances, but prioritizing prevention of externalizing behaviors holds promise for preventing both alcohol and cannabis misuse in established adulthood.


Assuntos
Cannabis , Transtornos Relacionados ao Uso de Substâncias , Criança , Feminino , Adolescente , Adulto , Humanos , Masculino , Estudos Longitudinais , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Fatores de Risco
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