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1.
Heliyon ; 10(7): e28345, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38689989

RESUMO

Background: Numerous research studies have delved into the biomechanics of walking, focusing on the spine and lower extremities. However, understanding the symmetry of walking in individuals without health issues poses a challenge, as those with normal mobility may exhibit uneven movement patterns due to inherent functional differences between their left and right limbs. The goal of this study is to examine the three-dimensional kinematics of gait symmetry in the spine and lower body during both typical and brisk overground walking in healthy individuals. The analysis will utilize statistical methods and symmetry index approaches. Furthermore, the research aims to investigate whether factors such as gender and walking speed influence gait symmetry. Methods: Sixty young adults in good health, comprising 30 males and 30 females, underwent motion capture recordings while engaging in both normal and fast overground walking. The analysis focused on interlimb comparisons and corresponding assessments of side-specific spine and pelvis motions. Results: Statistical Parametric Mapping (SPM) predominantly revealed gait symmetries between corresponding left and right motions in the spine, pelvis, hip, knee, and ankle during both normal and fast overground walking. Notably, both genders exhibited asymmetric pelvis left-right obliquity, with women and men showing an average degree of asymmetry between sides of 0.9 ± 0.1° and 1.5 ± 0.1°, respectively. Furthermore, the analysis suggested that neither sex nor walking speed appeared to exert influence on the 3D kinematic symmetry of the spine, pelvis, and lower body in healthy individuals during gait. While the maximum normalized symmetry index (SInorm) values for the lower thorax, upper lumbar, lower lumbar, pelvis, hip, knee, and ankle displayed significant differences between sexes and walking speeds for specific motions, no interaction between sex and walking speed was observed. Significance: The findings underscore the potential disparities in data interpretations between the two approaches. While SPM discerns temporal variations in movement, these results offer valuable insights that may enhance our comprehension of gait symmetry in healthy individuals, surpassing the limitations of straightforward discrete parameters like the maximum SInorm. The information gleaned from this study could serve as reference indicators for diagnosing and evaluating abnormal gait function.

2.
Kidney Int ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38685562

RESUMO

Cytomegalovirus (CMV) infection is associated with poor kidney transplant outcomes. While innate and adaptive immune cells have been implicated in its prevention, an in-depth characterization of the in vivo kinetics of multiple cell subsets and their role in protecting against CMV infection has not been achieved. Here, we performed high-dimensional immune phenotyping by mass cytometry, and functional assays, on 112 serially collected samples from CMV seropositive kidney transplant recipients. Advanced unsupervised deep learning analysis was used to assess immune cell populations that significantly correlated with prevention against CMV infection and anti-viral immune function. Prior to infection, kidney transplant recipients who developed CMV infection showed significantly lower CMV-specific cell-mediated immune (CMI) frequencies than those that did not. A broad diversity of circulating cell subsets within innate and adaptive immune compartments were associated with CMV infection or protective CMV-specific CMI. While percentages of CMV (tetramer-stained)-specific T cells associated with high CMI responses and clinical protection, circulating CD3+CD8midCD56+ NK-T cells overall strongly associated with low CMI and subsequent infection. However, three NK-T cell subsets sharing the CD11b surface marker associated with CMV protection and correlated with strong anti-viral CMI frequencies in vitro. These data were validated in two external independent cohorts of kidney transplant recipients. Thus, we newly describe the kinetics of a novel NK-T cell subset that may have a protective role in post-transplantation CMV infection. Our findings pave the way to more mechanistic studies aimed at understanding the function of these cells in protection against CMV infection.

3.
Int J Mol Sci ; 25(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38542163

RESUMO

Subclinical inflammation in protocol biopsies relates to tacrolimus exposure and human leukocyte antigen (HLA) matching. We aimed to characterize transcripts associated with rejection and tacrolimus exposure and the latter's association with transplant outcomes. We tested whether gene expression is associated with rejection using strictly normal protocol biopsies (n = 17) and biopsies with T cell-mediated rejection (TCMR) or antibody-mediated rejection (ABMR) according to Banff criteria (n = 12). Subsequently, we analyzed these transcripts in a set of 4-month protocol biopsies (n = 137) to assess their association with donor and recipient characteristics, the intensity of immunosuppression, and the graft outcome. Differential expression (false discovery rate (FDR) < 0.01, fold (change (FC) > 3) between normal and rejection biopsies yielded a set of 111 genes. In the protocol biopsy cohort (n = 137), 19 out of these 111 genes correlated with tacrolimus trough levels at the time of biopsy (TAC-C0), and unsupervised analysis split this cohort into two clusters. The two clusters differed in donor age and tacrolimus trough levels. Subclinical rejection, including borderline lesions, tended to occur in the same cluster. Logistic regression analysis indicated that TAC-C0 at the time of biopsy (OR: 0.83, 95%CI:0.72-0.06, p = 0.0117) was associated with cluster 2. In a follow-up averaging 70 ± 30 months, this patient group displayed a significant decline in renal function (p = 0.0135). The expression of rejection-associated transcripts in early protocol biopsies is associated with tacrolimus exposure and a faster decline in renal function.


Assuntos
Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Tacrolimo/efeitos adversos , Rejeição de Enxerto/genética , Biópsia , Terapia de Imunossupressão , Imunossupressores/efeitos adversos
4.
Acta Otolaryngol ; : 1-6, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37975845

RESUMO

BACKGROUND: Cochlear implants are standard of care for the patients with sensorineural hearing loss not benefited from hearing aids. AIMS: Evaluate qualitatively the impact of cochlear implantation in the long-term. MATERIALS-METHODS: Thirty middle-class patients with similar patterns of loss and social environment averaging 20 years post-implantation responded to 52 questions that evaluated psychosocial benefits from cochlear implantation. RESULTS: All completed secondary education and 93% had postgraduate studies. Educational and workwise they are at the same level as their hearing counterparts. All use their cochlear implants and would recommend one to people who need it. They attribute their success to the implant, the rehabilitation program, their family, and a stimulating social environment. Despite their success, most experience difficulties relating with others (socially and at work) due to their hearing condition. They manage but work much harder than their hearing peers to achieve the same. CONCLUSIONS: We made a difference in the lives of these patients, however, there is more to be done. SIGNIFICANCE: Early intervention, rehabilitation, plus family, and stimulating-environment are crucial in children with sensory deficits.

5.
Sci Rep ; 13(1): 19437, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945639

RESUMO

The bundle of forest landowners' rights largely varies from one jurisdiction to another. On a global scale, the diversity of forest management regime and property rights systems is such that finding comprehensive and standardised approaches for governance analysis purposes is a challenging task. This paper explores the use of the Property Rights Index for Forestry (PRIF) as an analytical tool based on five rights domains (access, withdrawal, management, exclusion, and alienation) to assess how regulatory frameworks impact the owners' forest property rights. We show that PRIF is a reliable index for various governance arrangements, considering its ability to score forest owners' freedom to decide in case studies that range from the Amazon area (Brazil), Misiones province (Argentina) and Quebec (Canada) to community-managed Nepalese and Mexican forests. PRIF scores obtained in these diverse governance arrangements confirm that the governance of forests held by entities other than the state is driven by two factors: the owner's ability to exclude the public from the use of his/her own resource and the owner's freedom to decide on the forest management goals. These factors explained 66.44% of the variance in our sample and should be considered as the main potential drivers while implementing any new international or national policy. Despite having a few limitations, the PRIF is a promising governance indicator and has been proven to perform well for various socioeconomic and legal contexts.


Assuntos
Conservação dos Recursos Naturais , Propriedade , Feminino , Masculino , Humanos , Florestas , Agricultura Florestal , Canadá
6.
J Phys Chem A ; 127(41): 8663-8675, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37801706

RESUMO

In this paper, we study the quantum time evolution of oblique nonstationary vibrational states in a Hénon-Heiles oscillator system with two dissociation channels, which models the stretching vibrational motions of triatomic molecules. The oblique nonstationary states we are interested in are the eigenfunctions of the anharmonic zero-order Hamiltonian operator resulting from the transformation to oblique coordinates, which are defined as those coming from nonorthogonal coordinate rotations that express the matrix representation of the second-order Hamiltonian in a block diagonal form characterized by the polyadic quantum number n = n1 + n2. The survival probabilities calculated show that the oblique nonstationary states evolve within their polyadic group with a high degree of coherence up to the dissociation limits on the short time scale. The degree of coherence is certainly much higher than that exhibited by the local nonstationary states extracted from the conventional orthogonal rotation of the original normal coordinates. We also show that energy exchange between the oblique vibrational modes occurs in a much more regular way than the exchange between the local modes.

7.
Curr Opin Organ Transplant ; 28(5): 345-354, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37678170

RESUMO

PURPOSE OF REVIEW: The implementation of highly sensitive immune assays measuring anti-human leukocyte antigen (HLA) antibodies has modified alloimmune risk stratification and diagnosis of rejection. Nonetheless, anti-HLA antibodies represent the downstream effector mechanism of the B-cell response. Better characterizing the cellular components of the humoral immune response (including memory B cells (mBCs) and long-lived plasma cells) could help to further stratify the alloimmune risk stratification and enable discovery of new therapeutic targets. Several tests that characterize HLA-specific mBCs, either functionally or phenotypically, have been developed in the last years, showing promising applications as well as some limitations. RECENT FINDINGS: Functional assays involving ex vivo polyclonal activation of mBC have been refined to allow the detection of HLA-specific mBC capable of producing anti-HLA Abs, using different and complementary detection platforms such as multiplex Fluorospot and single antigen bead assay on culture supernatants. Detection of circulating HLA-specific B cells by flow cytometry remains hindered by the very low frequency of HLA-specific mBC. SUMMARY: Technological refinements have allowed the development of tests detecting HLA-specific mBC. Further evaluation of these assays in clinical trials, both for immune risk stratification and to assess treatment efficacy (desensitization strategies, rescue therapies for ABMR) are now urgently needed.


Assuntos
Linfócitos B , Imunidade Humoral , Humanos , Citometria de Fluxo
8.
Biosens Bioelectron ; 232: 115291, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060864

RESUMO

Rabies is a lethal zoonotic disease caused by rabies virus (RABV) that affects human health and the economy. RABV is transmitted mainly by bats in Brazil, and surveillance in remote areas is hampered by the difficulty of properly collecting samples during fieldwork and the diagnosis is performed in laboratory conditions. Here, we report a portable electrochemical biosensor based on nucleic acid interactions for RABV detection in nasopharyngeal swab samples. The working electrode of the biosensor is composed of reduced graphene oxide (rGO) thin-film immobilized with cDNA through pi-pi stacking to enhance virus detection and specificity. Sensor performance was determined using RNA, and swab samples from bats. RNA detection shows good selectivity, and quantification presents a highly linear calibration curve (R2 = 0.990) using a concentration range of 0.145-25.39 ng/µL. A LOD of 0.104 ng/µL was reached with a sensitivity of 0.321 µA (ng/µL)-1. RABV detection in nasopharyngeal swab samples showed a good difference of positive sample from negative with a response time in seconds, ultra-fast detection compared to known techniques. Three biosensor groups were identified and named after physic-chemical surface characterization as: GO-1, GO-2, and rGO; with best performance for rGO group due to its sp2 hybridized network. Thus, we have successfully fabricated a promising electrochemical biosensor for fast in-situ detection of the RABV in swab samples, which can be expanded to other enveloped viruses that have RNA.


Assuntos
Técnicas Biossensoriais , Quirópteros , Grafite , Vírus da Raiva , Raiva , Animais , Humanos , Vírus da Raiva/genética , Quirópteros/genética , Raiva/diagnóstico , Raiva/veterinária , Raiva/epidemiologia , Grafite/química , RNA , Nasofaringe
9.
Micromachines (Basel) ; 14(3)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36984919

RESUMO

This paper presents the converter design of a single-phase non-isolated step-down controlled rectifier for power factor improvement and output voltage regulation. The converter consists of a full-bridge diode rectifier and a DC-DC interleaved buck converter of two or more switching cells that has an LC filter in its input. It is proposed that the interleaved switching cells operate in discontinuous conduction mode and the current through the input LC filter be continuous, avoiding switching frequency components to be injected into the grid. The controller, which has a simple structure and a small number of sensors, allows the system to achieve a high power factor. It also regulates the output voltage to a constant reference. An experimental prototype is built and tested to validate the analysis and proposed design. The closed-loop converter is evaluated both in a steady state and in transient conditions. At steady state, the converter achieves a power factor above 0.9 with a maximum of 45.4% THD at 110.1W. The main contributions of this paper are guidelines for the design of the converter, open-loop analysis, and converter control.

10.
Phys Chem Chem Phys ; 25(15): 10512-10524, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36987865

RESUMO

The study of proteins with intrinsically disordered regions (IDRs) has emerged as an active field of research due to their intriguing nature. Although IDRs lack a well-defined folded structure, they play important functional roles in cells, following biological mechanisms different from those of the traditional structured proteins. Consequently, it has been necessary to re-design experimental and theoretical methods in order to face the challenges introduced by the dynamic nature of IDRs. In this work, we present an accurate and cost-effective method to study the conformational dynamics of IDRs based on the use of residue-local probabilistic expressions that characterize the conformational ensembles obtained from finite-temperature molecular dynamics (MD) simulations. It is shown that the good performance and the high convergence rates achieved with our method are independent of the IDR lengths, since the method takes advantage of the major influence of the identity and conformation of the nearest residue neighbors on the amino-acid conformational preferences to evaluate the IDR conformational ensembles. This allows us to characterize the conformational space of IDRs using a reduced number of probabilities which can be obtained from comparatively short MD simulations or experimental databases. To exemplify the usefulness of our approach, we present an application to directly detect Molecular Recognition Features (MoRFs) in an IDR domain of the protein p53, and to follow the time evolution of the thermodynamic magnitudes of this system during its exploration of the conformational space.


Assuntos
Proteínas Intrinsicamente Desordenadas , Conformação Proteica , Proteínas Intrinsicamente Desordenadas/química , Simulação de Dinâmica Molecular , Probabilidade , Aminoácidos
12.
Front Immunol ; 13: 924825, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248818

RESUMO

Complete and high-resolution (HR) HLA typing improves the accurate assessment of donor-recipient compatibility and pre-transplant donor-specific antibodies (DSA). However, the value of this information to identify de novo immune-mediated graft events and its impact on outcomes has not been assessed. In 241 donor/recipient kidney transplant pairs, DNA samples were re-evaluated for six-locus (A/B/C/DRB1/DQB1+A1/DPB1) HR HLA typing. De novo anti-HLA antibodies were assessed using solid-phase assays, and dnDSA were classified either (1) as per current clinical practice according to three-locus (A/B/DRB1) low-resolution (LR) typing, estimating donor HLA-C/DQ typing with frequency tables, or (2) according to complete six-locus HR typing. The impact on graft outcomes was compared between groups. According to LR HLA typing, 36 (15%) patients developed dnDSA (LR_dnDSA+). Twenty-nine out of 36 (80%) were confirmed to have dnDSA by HR typing (LR_dnDSA+/HR_dnDSA+), whereas 7 (20%) did not (LR_dnDSA+/HR_dnDSA-). Out of 49 LR_dnDSA specificities, 34 (69%) were confirmed by HR typing whereas 15 (31%) LR specificities were not confirmed. LR_dnDSA+/HR_dnDSA+ patients were at higher risk of ABMR as compared to dnDSA- and LR_dnDSA+/HR_dnDSA- (logRank < 0.001), and higher risk of death-censored graft loss (logRank = 0.001). Both LR_dnDSA+ (HR: 3.51, 95% CI = 1.25-9.85) and LR_dnDSA+/HR_dnDSA+ (HR: 4.09, 95% CI = 1.45-11.54), but not LR_dnDSA+/HR_dnDSA- independently predicted graft loss. The implementation of HR HLA typing improves the characterization of biologically relevant de novo anti-HLA DSA and discriminates patients with poorer graft outcomes.


Assuntos
Rejeição de Enxerto , Antígenos HLA , Rejeição de Enxerto/diagnóstico , Sobrevivência de Enxerto , Antígenos HLA/genética , Antígenos HLA-C , Teste de Histocompatibilidade , Humanos
13.
Vaccines (Basel) ; 10(9)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36146621

RESUMO

The CoronaVac vaccine is the most used anti-SARS-CoV-2 vaccine worldwide. Previous data indicate that this vaccine produces a lower immune response than RNA vaccines such as BNT162b2. End-stage renal disease (ESRD) patients have an increased rate of COVID-19 and a reduced immune response to vaccinations. Currently, there is little data on this population's immune response induced by CoronaVac. Methods: This study involved a prospective cohort of ESRD patients in chronic hemodialysis who received a two-dose immunization scheme of either CoronaVac (Sinovac Biotech) or BNT162b2 vaccines (Pfizer-BioNTech). We measured the plasma levels of anti-SARS-CoV-2 IgG antibodies. We determined antibody titers before immunization, 2 and 4 months after two doses, plus 4 months after a booster dose. Results: We evaluated 208 patients in three hemodialysis centers. The mean age was 62.6 ± 15.6 years, of whom 91 were female (41.75%). Eighty-one patients (38.94%) received the BNT162b2 vaccine and 127 (61.06%) received the CoronaVac vaccine. Patients who received the BNT162b2 vaccine had a higher humoral response compared to those who received the CoronaVac vaccine (4 months after the second dose: BNT162b2: 88.89%, CoronaVac: 51.97%, p < 0.001; 4 months after the booster: BNT162b2: 98.77%, CoronaVac: 86.61%, p < 0.001). Conclusions: Our results suggest that the CoronaVac vaccine induced a lower humoral response than the BNT162b2 vaccine in ESRD patients on hemodialysis.

14.
Bol Med Hosp Infant Mex ; 79(Supl 1): 1-31, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35943405

RESUMO

BACKGROUND: Acute otitis media (AOM) is one of the most prevalent acute conditions in the pediatric population worldwide. This work aimed to elaborate a Clinical Practice Guideline with clinical recommendations systematically developed to assist decision-making of specialists, patients, caregivers, and public policymakers involved in managing patients with AOM in children. METHODS: This document was developed by the College of Pediatric Otorhinolaryngology and Head, and Neck Surgery of Mexico (COPEME) in compliance with international standards. The SIGN quality of evidence classification was used. On behalf of the COPEME, the Guideline Development Group (GDG) was integrated, including otolaryngologists, infectologists, pediatricians, general practitioners, and methodologists with experience in systematic literature reviews and the development of clinical practice guidelines. RESULTS: A consensus was reached on 18 clinical questions, covering what was previously established by the GDG in the scope document of the guidelines. Scientific evidence answering each of these clinical questions was identified and critically evaluated. The GDG agreed on the final wording of the clinical recommendations using the modified Delphi panel technique. Specialists and patient representatives conducted an external validation. CONCLUSIONS: This Clinical Practice Guideline presents clinical recommendations for the prevention, diagnosis, and management of AOM to assist shared decision-making among physicians, patients, and caregivers and improve the quality of clinical care.


INTRODUCCIÓN: La otitis media aguda (OMA) es uno de los padecimientos agudos más prevalentes en la población pediátrica a escala global. El objetivo de este trabajo fue elaborar una guía de práctica clínica con recomendaciones para asistir la toma de decisiones de médicos especialistas, pacientes, cuidadores de pacientes y elaboradores de políticas públicas involucrados en el manejo de la OMA en niños. MÉTODOS: El documento ha sido desarrollado por parte del Colegio de Otorrinolaringología y Cirugía de Cabeza y Cuello Pediátricas de México (COPEME) en cumplimiento con los estándares internacionales. Se empleó la clasificación de calidad de la evidencia de SIGN. En representación del COPEME, se integró el Grupo de Desarrollo de la Guía (GDG), que incluyó otorrinolaringólogos, infectólogos, pediatras, médicos generales y metodólogos con experiencia en revisiones sistemáticas de la literatura y el desarrollo de guías de práctica clínica. RESULTADOS: Se consensuaron 18 preguntas clínicas que abarcaron lo establecido previamente por el GDG en el documento de alcances de la Guía. Se identificó la evidencia científica que responde a cada una de estas preguntas clínicas y se evaluó críticamente. El GDG acordó la redacción final de las recomendaciones clínicas mediante la técnica Delphi de panel. Se llevó a cabo una validación externa por colegas especialistas y representantes de pacientes. CONCLUSIONES: En esta Guía de Práctica Clínica se presentan recomendaciones clínicas para la prevención, el diagnóstico y el manejo de la OMA, con el fin de asistir la toma de decisiones compartidas entre médicos, pacientes y cuidadores con la intención de contribuir a mejorar la calidad de la atención clínica.


Assuntos
Otite Média , Doença Aguda , Criança , Humanos , México , Otite Média/diagnóstico
17.
Bol. méd. Hosp. Infant. Méx ; 79(supl.1): 1-31, jul. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1429933

RESUMO

Resumen Introducción: La otitis media aguda (OMA) es uno de los padecimientos agudos más prevalentes en la población pediátrica a escala global. El objetivo de este trabajo fue elaborar una guía de práctica clínica con recomendaciones para asistir la toma de decisiones de médicos especialistas, pacientes, cuidadores de pacientes y elaboradores de políticas públicas involucrados en el manejo de la OMA en niños. Métodos: El documento ha sido desarrollado por parte del Colegio de Otorrinolaringología y Cirugía de Cabeza y Cuello Pediátricas de México (COPEME) en cumplimiento con los estándares internacionales. Se empleó la clasificación de calidad de la evidencia de SIGN. En representación del COPEME, se integró el Grupo de Desarrollo de la Guía (GDG), que incluyó otorrinolaringólogos, infectólogos, pediatras, médicos generales y metodólogos con experiencia en revisiones sistemáticas de la literatura y el desarrollo de guías de práctica clínica. Resultados: Se consensuaron 18 preguntas clínicas que abarcaron lo establecido previamente por el GDG en el documento de alcances de la Guía. Se identificó la evidencia científica que responde a cada una de estas preguntas clínicas y se evaluó críticamente. El GDG acordó la redacción final de las recomendaciones clínicas mediante la técnica Delphi de panel. Se llevó a cabo una validación externa por colegas especialistas y representantes de pacientes. Conclusiones: En esta Guía de Práctica Clínica se presentan recomendaciones clínicas para la prevención, el diagnóstico y el manejo de la OMA, con el fin de asistir la toma de decisiones compartidas entre médicos, pacientes y cuidadores con la intención de contribuir a mejorar la calidad de la atención clínica.


Abstract Background: Acute otitis media (AOM) is one of the most prevalent acute conditions in the pediatric population worldwide. This work aimed to elaborate a Clinical Practice Guideline with clinical recommendations systematically developed to assist decision-making of specialists, patients, caregivers, and public policymakers involved in managing patients with AOM in children. Methods: This document was developed by the College of Pediatric Otorhinolaryngology and Head, and Neck Surgery of Mexico (COPEME) in compliance with international standards. The SIGN quality of evidence classification was used. On behalf of the COPEME, the Guideline Development Group (GDG) was integrated, including otolaryngologists, infectologists, pediatricians, general practitioners, and methodologists with experience in systematic literature reviews and the development of clinical practice guidelines. Results: A consensus was reached on 18 clinical questions, covering what was previously established by the GDG in the scope document of the guidelines. Scientific evidence answering each of these clinical questions was identified and critically evaluated. The GDG agreed on the final wording of the clinical recommendations using the modified Delphi panel technique. Specialists and patient representatives conducted an external validation. Conclusions: This Clinical Practice Guideline presents clinical recommendations for the prevention, diagnosis, and management of AOM to assist shared decision-making among physicians, patients, and caregivers and improve the quality of clinical care.

20.
J Phys Chem A ; 125(41): 9226-9241, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34613734

RESUMO

In this work, we calculate the partition functions and thermodynamic quantities of molecular hydrogen isotopologues using the rovibrational energy levels provided by the highly accurate ab initio adiabatic potential energy functions recently determined by Pachucki and Komasa (Pachucki, K.; Komasa, J. J. Chem. Phys. 2014, 141, 224103). The partition functions are calculated by including all bound energy levels of the isotopologues, up to their dissociation limits, plus the quasi-bound levels lying below the centrifugal potential barriers. For the homonuclear isotopologues, H2, D2, and T2, we also determine the partition functions and thermodynamic quantities of the normal mixtures using the statistical treatment recently proposed by Colonna et al. (Colonna, G.; D'Angola, A.; Capitelli, M. Int. J. Hydrogen Energy 2012, 37, 9656) based on the definition of the partition function of the mixture, which avoids inconsistencies in the values of the thermodynamic quantities depending directly on the internal partition function, in the high-temperature limit.

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