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1.
Nat Immunol ; 17(3): 250-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26642356

RESUMEN

The NLRP3 inflammasome responds to microbes and danger signals by processing and activating proinflammatory cytokines, including interleukin 1ß (IL-1ß) and IL-18. We found here that activation of the NLRP3 inflammasome was restricted to interphase of the cell cycle by NEK7, a serine-threonine kinase previously linked to mitosis. Activation of the NLRP3 inflammasome required NEK7, which bound to the leucine-rich repeat domain of NLRP3 in a kinase-independent manner downstream of the induction of mitochondrial reactive oxygen species (ROS). This interaction was necessary for the formation of a complex containing NLRP3 and the adaptor ASC, oligomerization of ASC and activation of caspase-1. NEK7 promoted the NLRP3-dependent cellular inflammatory response to intraperitoneal challenge with monosodium urate and the development of experimental autoimmune encephalitis in mice. Our findings suggest that NEK7 serves as a cellular switch that enforces mutual exclusivity of the inflammasome response and cell division.


Asunto(s)
Proteínas Portadoras/inmunología , Macrófagos/inmunología , Mitosis/inmunología , Proteínas Serina-Treonina Quinasas/inmunología , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis , Proteínas Adaptadoras de Señalización CARD , Proteínas Portadoras/genética , Caspasa 1 , Cromatografía en Gel , Ensayo de Unidades Formadoras de Colonias , Citocinas , Proteínas del Citoesqueleto , Células Dendríticas , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Citometría de Flujo , Células HEK293 , Humanos , Inmunoprecipitación , Técnicas In Vitro , Inflamasomas/genética , Inflamasomas/inmunología , Macrófagos Peritoneales/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias/metabolismo , Monocitos , Quinasas Relacionadas con NIMA , Proteína con Dominio Pirina 3 de la Familia NLR , Proteínas Serina-Treonina Quinasas/genética , Especies Reactivas de Oxígeno , Médula Espinal/inmunología
2.
J Thromb Thrombolysis ; 49(3): 501-503, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31820264

RESUMEN

Nitrous oxide is a commonly abused inhalant by adolescents and young adults. There is limited data describing the adverse effects of nitrous oxide abuse, known colloquially as "whippets". We present a 21-year-old female with no medical history who presented to the emergency department for confusion, hallucinations, weakness, and falls. She was accompanied by her roommates, who endorsed significant nitrous oxide abuse. Imaging revealed a large cerebral sinus venous thrombus with extension into the transverse sinus, sigmoid sinus and internal jugular vein. She had no prior history of venous or arterial thrombosis. Hypercoagulability workup demonstrated an elevated homocysteine level, elevated methylmalonic acid level, and normal cobalamin and folate levels. Additionally, she was found to be 11 weeks pregnant, with no prior spontaneous abortions. Genetic testing was significant for methylenetetrahydrofolate reductase polymorphisms. She was managed with enoxaparin, cobalamin and folate supplementation. Homocysteine and methylmalonic acid levels normalized after cessation of nitrous oxide use, with no recurrence of venous thrombosis. This case represents the first reported patient with a venous thrombus associated with nitrous oxide abuse.


Asunto(s)
Enoxaparina/administración & dosificación , Ácido Fólico/administración & dosificación , Óxido Nitroso/efectos adversos , Trombosis de los Senos Intracraneales , Trombosis de la Vena , Vitamina B 12/administración & dosificación , Adulto , Femenino , Humanos , Óxido Nitroso/administración & dosificación , Trombosis de los Senos Intracraneales/inducido químicamente , Trombosis de los Senos Intracraneales/diagnóstico por imagen , Trombosis de los Senos Intracraneales/tratamiento farmacológico , Trombosis de la Vena/inducido químicamente , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/tratamiento farmacológico
4.
Proc Natl Acad Sci U S A ; 112(5): E440-9, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25605905

RESUMEN

With the wide availability of massively parallel sequencing technologies, genetic mapping has become the rate limiting step in mammalian forward genetics. Here we introduce a method for real-time identification of N-ethyl-N-nitrosourea-induced mutations that cause phenotypes in mice. All mutations are identified by whole exome G1 progenitor sequencing and their zygosity is established in G2/G3 mice before phenotypic assessment. Quantitative and qualitative traits, including lethal effects, in single or multiple combined pedigrees are then analyzed with Linkage Analyzer, a software program that detects significant linkage between individual mutations and aberrant phenotypic scores and presents processed data as Manhattan plots. As multiple alleles of genes are acquired through mutagenesis, pooled "superpedigrees" are created to analyze the effects. Our method is distinguished from conventional forward genetic methods because it permits (1) unbiased declaration of mappable phenotypes, including those that are incompletely penetrant (2), automated identification of causative mutations concurrent with phenotypic screening, without the need to outcross mutant mice to another strain and backcross them, and (3) exclusion of genes not involved in phenotypes of interest. We validated our approach and Linkage Analyzer for the identification of 47 mutations in 45 previously known genes causative for adaptive immune phenotypes; our analysis also implicated 474 genes not previously associated with immune function. The method described here permits forward genetic analysis in mice, limited only by the rates of mutant production and screening.


Asunto(s)
Mutación Puntual , Alelos , Animales , Femenino , Genes Letales , Ligamiento Genético , Masculino , Ratones , Linaje , Fenotipo , Sitios de Carácter Cuantitativo
5.
J Appl Biomech ; 34(6): 469-473, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29989457

RESUMEN

Asymmetry in weight-bearing is a common feature in poststroke hemiparesis and is related to temporal asymmetry during walking. The aim of this study was to investigate the effect of an auditory cue for stepping in place on measures of temporal and weight-bearing asymmetry. A total of 10 community-dwelling adults (6 males and 4 females) with chronic poststroke hemiparesis performed 5 un-cued stepping trials and 5 stepping trials cued by an auditory metronome cue. A Vicon system was used to collect full body kinematic trajectories. Two force platforms were used to measure ground reaction forces. Step, swing, and stance times were used to calculate temporal symmetry ratios. Weight-bearing was assessed using the vertical component of the ground reaction force and center of mass-center of pressure separation at mid-stance. Weight-bearing asymmetry was significantly reduced during stepping with an auditory cue. Asymmetry values for step, swing, and stance times were also significantly reduced with auditory cueing. These findings show that auditory cueing when stepping in place produces immediate reductions in measures of temporal asymmetry and dynamic weight-bearing asymmetry.

6.
Phys Chem Chem Phys ; 19(32): 21364-21372, 2017 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-28766614

RESUMEN

Conformational assignments in molecular beam experiments are often based on relative energies, although there are many other relevant parameters, such as conformer-dependent oscillator strengths, Franck-Condon factors, quantum yields and vibronic couplings. In the present contribution, we investigate the conformational landscape of 1,3-dimethoxybenzene using a combination of rotationally resolved electronic spectroscopy and high level ab initio calculations. The electronic origin of one of the three possible planar rotamers (rotamer (0,180) with both substituents pointing at each other) has not been found. Based on the calculated potential energy surface of 1,3-dimethoxybenzene in the electronic ground and lowest excited state, we show that this can be explained by a distorted non-planar geometry of rotamer (0,180) in the S1 state.

7.
Angew Chem Int Ed Engl ; 56(51): 16122-16124, 2017 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-29116681

RESUMEN

Undoing the twist: Recent successful attempts to change the relative populations of two otherwise identical enantiomers of a large gas-phase molecule using resonant microwave fields are highlighted. Specifically, the population of a specific enantiomer of a chiral terpene could be enhanced relative to the other enantiomer by the application of a sequence of microwave pulses in a phase- and polarization-controlled manner.

8.
J Chem Phys ; 144(8): 084304, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26931699

RESUMEN

We determined the changes of the geometries of 2- and 3-tolunitrile upon excitation to the lowest excited singlet states from Franck-Condon fits of the vibronic intensities in several fluorescence emission spectra and of the rotational constant changes upon excitation. These structural changes can be connected to the altered electron distribution in the molecules and are compared to the results of ab initio calculations. We show how the torsional barriers of the methyl groups in both components are used as probe of the molecular changes upon electronic excitation.

9.
J Chem Phys ; 144(4): 044303, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26827213

RESUMEN

Rotationally resolved fluorescence excitation spectra of the origin bands in the S1 ← S0 transition of 2-tolunitrile (2TN) and 3-tolunitrile (3TN) have been recorded in the collision-free environment of a molecular beam. Analyses of these data provide the rotational constants of each molecule and the potential energy curves governing the internal rotation of the attached methyl groups in both electronic states. 2TN exhibits much larger barriers along this coordinate than 3TN. Interestingly, the electronic transition dipole moment in both molecules is markedly influenced by the position of the attached methyl group rather than the position of the cyano group; possible reasons for this intriguing behavior are discussed.

10.
Blood ; 122(8): e1-11, 2013 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-23861249

RESUMEN

Teleost fish are among the most ancient vertebrates possessing an adaptive immune system with B and T lymphocytes that produce memory responses to pathogens. Most bony fish, however, have only 2 types of B lymphocytes, in contrast to the 4 types available to mammals. To better understand the evolution of adaptive immunity, we generated transgenic zebrafish in which the major immunoglobulin M (IgM(+)) B-cell subset expresses green fluorescence protein (GFP) (IgM1:eGFP). We discovered that the earliest IgM(+) B cells appear between the dorsal aorta and posterior cardinal vein and also in the kidney around 20 days postfertilization. We also examined B-cell ontogeny in adult IgM1:eGFP;rag2:DsRed animals, where we defined pro-B, pre-B, and immature/mature B cells in the adult kidney. Sites of B-cell development that shift between the embryo and adult have previously been described in birds and mammals. Our results suggest that this developmental shift occurs in all jawed vertebrates. Finally, we used IgM1:eGFP and cd45DsRed;blimp1:eGFP zebrafish to characterize plasma B cells and investigate B-cell function. The IgM1:eGFP reporter fish are the first nonmammalian B-cell reporter animals to be described. They will be important for further investigation of immune cell evolution and development and host-pathogen interactions in zebrafish.


Asunto(s)
Linfocitos B/citología , Evolución Molecular , Pez Cebra/embriología , Pez Cebra/inmunología , Inmunidad Adaptativa , Animales , Animales Modificados Genéticamente , Linfocitos B/metabolismo , Genes Reporteros , Proteínas Fluorescentes Verdes/metabolismo , Sistema Inmunológico/embriología , Inmunoglobulina M/metabolismo , Activación de Linfocitos , Fagocitosis
11.
J Chem Phys ; 143(9): 094301, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26342364

RESUMEN

The molecular structures of guaiacol (2-methoxyphenol) and mequinol (4-methoxyphenol) have been studied using high resolution electronic spectroscopy in a molecular beam and contrasted with ab initio computations. Mequinol exhibits two low frequency bands that have been assigned to electronic origins of two possible conformers of the molecule, trans and cis. Guaiacol also shows low frequency bands, but in this case, the bands have been assigned to the electronic origin and vibrational modes of a single conformer of the isolated molecule. A detailed study of these bands indicates that guaiacol has a vibrationally averaged planar structure in the ground state, but it is distorted along both in-plane and out-of-plane coordinates in the first electronically excited state. An intramolecular hydrogen bond involving the adjacent -OH and -OCH3 groups plays a major role in these dynamics.

12.
J Phys Chem A ; 118(35): 7267-73, 2014 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-24392821

RESUMEN

The seven most stable conformers of D-threoninol (2(S)-amino-1,3(S)-butanediol), a template used for the synthesis of artificial nucleic acids, have been identified and characterized from their pure rotational transitions in the gas phase using chirped-pulse Fourier transform microwave spectroscopy. D-Threoninol is a close analogue of glycerol, differing by substitution of an NH2 group for OH on the C(ß) carbon and by the presence of a terminal CH3 group that breaks the symmetry of the carbon framework. Of the seven observed structures, two are H-bonded cycles containing three H-bonds that differ in the direction of the H-bonds in the cycle. The other five are H-bonded chains containing OH···NH···OH H-bonds with different directions along the carbon framework and different dihedral angles along the chain. The two structural types (cycles and chains of H-bonds) are in surprisingly close energetic proximity. Comparison of the rotational constants with the calculated structures at the MP2/6-311++G(d,p) level of theory reveals systematic changes in the H-bond distances that reflect NH2 as a better H-bond acceptor and poorer donor, shrinking the H-bond distances by ∼0.2 Å in the former case and lengthening them by a corresponding amount in the latter. Thus revealed is the subtle effect of asymmetric substitution on the energy landscape of a simple molecule, likely to be important in living systems.


Asunto(s)
Amino Alcoholes/química , Butileno Glicoles/química , Simulación por Computador , Enlace de Hidrógeno , Microondas , Modelos Químicos , Estructura Molecular , Rotación , Análisis Espectral
13.
Prev Chronic Dis ; 10: E43, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23537517

RESUMEN

INTRODUCTION: The Indo-Guyanese population is the largest immigrant minority population in Schenectady, New York. A clinic-based study in Schenectady and surveillance reports from Guyana found high diabetes prevalence and mortality among Guyanese of Indian descent. No community-based study has focused on diabetes among Indo-Guyanese immigrants in the United States. We sought information on the prevalence of diabetes and its complications in Indo-Guyanese adults in Schenectady and compared it with the prevalence among non-Hispanic white adults in Schenectady. METHODS: We administered a cross-sectional health survey at community venues in Schenectady in 2011. We identified diagnosed diabetes and its complications through self-reports by using a reliability-tested questionnaire. The final data set included 313 Indo-Guyanese and 327 non-Hispanic white adults aged 18 years or older. We compared the prevalence of diagnosed diabetes and diabetes complications between Indo-Guyanese and non-Hispanic whites. RESULTS: Most Indo-Guyanese participants were born in Guyana, whereas most non-Hispanic whites were born in the United States. The crude prevalence of diagnosed diabetes among Indo-Guyanese participants and non-Hispanic whites was 30.3% and 16.1%, respectively. The age-standardized prevalence was 28.7% among Indo-Guyanese participants, significantly higher than that among non-Hispanic whites (14.5%, P < .001). Indo-Guyanese participants who had diabetes had a lower body mass index and were more likely to report poor or fair general health and eye or vision complications than non-Hispanic whites who had diabetes. CONCLUSION: Our study confirms the higher prevalence of diabetes in Indo-Guyanese adults in Schenectady. The higher prevalence of complications suggests poor control of diabetes. Excess burden of diabetes in this population calls for further research and public health action.


Asunto(s)
Diabetes Mellitus/epidemiología , Indicadores de Salud , Adulto , Estudios Transversales , Complicaciones de la Diabetes/etnología , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/etnología , Emigrantes e Inmigrantes/estadística & datos numéricos , Femenino , Guyana/etnología , Humanos , India/etnología , Masculino , Persona de Mediana Edad , Mortalidad/etnología , New York/epidemiología , Prevalencia
14.
Phys Chem Chem Phys ; 14(25): 8990-8, 2012 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-22382507

RESUMEN

Hydrogen bond pairs involving the chromophore indole have been extensively studied in the gas phase. Here, we report high resolution electronic spectroscopy experiments on the indole-NH(3) hydrogen bond pair in the absence and presence of an electric field. The S(1)-S(0) origin band of this complex recorded in zero field at high resolution reveals two overlapping spectra; a consequence of NH(3) hindered internal rotation. The barrier to internal rotation is predicted by theory to be less than 20 cm(-1) in the ground state, therefore requiring a non-rigid rotor Hamiltonian to interpret the spectra. Conducting the experiment in the presence of an applied electric field further perturbs the already congested spectrum of the complex, but makes possible the measurement of the permanent electric dipole moments in its S(0) and S(1) states. These values reveal significant changes in electron distribution that arise from hydrogen bonding effects.


Asunto(s)
Amoníaco/química , Indoles/química , Enlace de Hidrógeno , Modelos Moleculares , Espectrometría de Fluorescencia
15.
Int J Health Serv ; 52(3): 363-371, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35546103

RESUMEN

The process of developing and marketing new pharmaceuticals in the United States is driven by a need to maximize returns to shareholders. This results all too often in the production of new medications that are expensive and of marginal value to patients and society. In line with our heightened awareness of the importance of social justice and public health-and in light of our government's alliance with private companies in bringing us COVID-19 vaccines-we need to reconsider how new pharmaceuticals are developed and distributed. Accordingly, we propose the creation of a new agency of the Food and Drug Administration (FDA) that would direct the whole process. This agency would fund the research and development of high-value medications, closely monitor the clinical studies of these new drugs, and manage their distribution at prices that are value-based, fair, and equitable.


Asunto(s)
Desarrollo de Medicamentos , Industria Farmacéutica , United States Food and Drug Administration , Vacunas contra la COVID-19 , Desarrollo de Medicamentos/legislación & jurisprudencia , Desarrollo de Medicamentos/organización & administración , Humanos , Mercadotecnía , Preparaciones Farmacéuticas , Estados Unidos
16.
Chemphyschem ; 12(10): 1808-15, 2011 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-21557435

RESUMEN

A theoretical and experimental investigation of meta-aminobenzoic acid (MABA) in the gas phase is presented, with the goal of understanding counterintuitive observations on the solvatochromism of this "push-pull" molecule. The adiabatic excitation energies, transition moments, and excited-state structures are examined using the complete active space self-consistent field approach (CASSCF and CASPT2), which shows the first excited electronic state of MABA to be of greater charge transfer character than was found in the para-isomer (PABA). The rotationally resolved electronic spectrum of MABA reveals the existence of two rotamers, owing to asymmetry in the carboxylic acid functional group. Stark measurements in a molecular beam show the change in permanent dipole moment upon excitation to be Δµ≈3.5 D for both rotamers, more than three times larger than that found in PABA. The excited state measurements reported here, along with supporting data from theory, clearly demonstrate how the meta-directing effects of asymmetric substitution in aniline derivatives can drive charge transfer pathways in the isolated molecule.

17.
Phys Chem Chem Phys ; 13(16): 7253-62, 2011 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-21394332

RESUMEN

Recent advances in the technology of test and measurement equipment driven by the computer and telecommunications industries have made possible the development of a new broadband, Fourier-transform microwave spectrometer that operates on principles similar to FTNMR. This technique uses a high sample-rate arbitrary waveform generator to construct a phase-locked chirped microwave pulse that gives a linear frequency sweep over a wide frequency range in 1 µs. The chirped pulse efficiently polarizes the molecular sample at all frequencies lying within this band. The subsequent free induction decay of this polarization is measured with a high-speed digitizer and then fast Fourier-transformed to yield a broadband, frequency-resolved rotational spectrum, spanning up to 11.5 GHz and containing lines that are as narrow as 100 kHz. This new technique is called chirped-pulse Fourier transform microwave (CP-FTMW) spectroscopy. The technique offers the potential to determine the structural and dynamical properties of very large molecules solely from fully resolved pure rotational spectra. FTMW double resonance techniques employing a low-resolution UV laser facilitate an easy assignment of overlapping spectra produced by different conformers in the sample. Of particular interest are the energy landscapes of conformationally flexible molecules of biological importance, including studies of their interaction with solvent and/or other weakly bound molecules. An example is provided from the authors' work on p-methoxyphenethylamine, a neurotransmitter, and its complexes with water.


Asunto(s)
Análisis de Fourier , Microondas , Electrones , Espectroscopía de Resonancia Magnética , Termodinámica , Tiramina/análogos & derivados , Tiramina/química , Rayos Ultravioleta , Agua/química
18.
J Phys Chem A ; 115(41): 11369-77, 2011 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-21790205

RESUMEN

Rotationally resolved electronic spectra of several low frequency vibrational bands that appear in the S(1) ← S(0) transition of 4-fluorobenzyl alcohol (4FBA) in the collision-free environment of a molecular beam have been observed and assigned. Each transition is split into two or more components by the tunneling motion of the attached -CH(2)OH group. A similar splitting is observed in the microwave spectrum of 4FBA. Analyses of these data show that 4FBA has a gauche structure in both electronic states, but that the ground state C(1)C(2)-C(7)O dihedral angle of ∼60° changes by ∼30° when the photon is absorbed. The barriers to the torsional motion of the attached -CH(2)OH group are also quite different in the two electronic states; V(2) ∼ 300 cm(-1) high and ∼60° wide in the S(0) state, and V(2) ∼ 300 cm(-1) high and ∼120° wide (or V(2) ∼ 1200 cm(-1) high and ∼60° wide) in the S(1) state. Possible reasons for these behaviors are discussed.


Asunto(s)
Compuestos de Bencilo/química , Metanol/química , Microondas , Teoría Cuántica , Electrones , Estructura Molecular , Espectrofotometría Ultravioleta
19.
J Phys Chem A ; 115(46): 13281-90, 2011 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-22023157

RESUMEN

We report the analysis of the S1<--S0 rotational band contours of jet-cooled 5-methyl-2-hydroxypyrimidine (5M2HP), the enol form of deoxythymine. Unlike thymine, which exhibits a structureless spectrum, the vibronic spectrum of 5M2HP is well structured, allowing us to determine the rotational constants and the methyl group torsional barriers in the S0 and S1 states. The 0(0)(0), 6a(0)(1), 6b(0)(1), and 14(0)(1) band contours were measured at 900 MHz (0.03 cm(-1)) resolution using mass-specific two-color resonant two-photon ionization (2C-R2PI) spectroscopy. All four bands are polarized perpendicular to the pyrimidine plane (>90% c type), identifying the S1<--S0 excitation of 5M2HP as a 1nπ* transition. All contours exhibit two methyl rotor subbands that arise from the lowest 5-methyl torsional states 0A" and 1E". The S0 and S1 state torsional barriers were extracted from fits to the torsional subbands. The 3-fold barriers are V3" = 13 cm(-1) and V3' = 51 cm(-1); the 6-fold barrier contributions V6" and V6' are in the range of 2-3 cm(-1) and are positive in both states. The changes of A, B, and C rotational constants upon S1 <--S0 excitation were extracted from the contours and reflect an "anti-quinoidal" distortion. The 0(0)(0) contour can only be simulated if a 3 GHz Lorentzian line shape is included, which implies that the S1(1nπ*) lifetime is ~55 ps. For the 6a(0)(1) and 6b(0)(1) bands, the Lorentzian component increases to 5.5 GHz, reflecting a lifetime decrease to ~30 ps. The short lifetimes are consistent with the absence of fluorescence from the 1nπ* state. Combining these measurements with the previous observation of efficient intersystem crossing (ISC) from the S1 state to a long-lived T1 (3nπ*) state that lies ~2200 cm(-1) below [S. Lobsiger, S. et al. Phys. Chem. Chem. Phys. 2010, 12, 5032] implies that the broadening arises from fast intersystem crossing with k(ISC) ≈ 2 × 10(10) s(-1). In comparison to 5-methylpyrimidine, the ISC rate is enhanced by at least 10 000 by the additional hydroxy group in position 2.


Asunto(s)
Pirimidinonas/química , Teoría Cuántica , Estructura Molecular
20.
J Phys Chem A ; 115(34): 9557-66, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21667948

RESUMEN

Rotationally resolved fluorescence excitation spectroscopy has been used to study the dynamics, electronic distribution, and the relative orientation of the transition moment vector in several vibronic transitions of acenaphthene (ACN) and in its Ar van der Waals (vdW) complex. The 0(0)(0) band of the S(1) ← S(0) transition of ACN exhibits a transition moment orientation parallel to its a-inertial axis. However, some of the vibronic bands exhibit a transition moment orientation parallel to the b-inertial axis, suggesting a Herzberg-Teller coupling with the S(2) state. Additionally, some other vibronic bands exhibit anomalous intensity patterns in several of their rotational transitions. A Fermi resonance involving two near degenerate vibrations has been proposed to explain this behavior. The high-resolution electronic spectrum of the ACN-Ar vdW complex has also been obtained and fully analyzed. The results indicate that the weakly attached argon atom is located on top of the plane of the bare molecule at ~3.48 Šaway from its center of mass in the S(0) electronic state.

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