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1.
Small Methods ; : e2400258, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38962863

ABSTRACT

Nanoengineering polar oxide films have attracted great attention in energy storage due to their high energy density. However, most of them are deposited on thick and rigid substrates, which is not conducive to the integration of capacitors and applications in flexible electronics. Here, an alternative strategy using van der Waals epitaxial oxide dielectrics on ultra-thin flexible mica substrates is developed and increased the disorder within the system through high laser flux. The introduction of defects can efficiently weaken or destroy the long-range ferroelectric ordering, ultimately leading to the emergence of a large numbers of weak-coupling regions. Such polarization configuration ensures fast polarization response and significantly improves energy storage characteristics. A flexible BiFeO3-BaTiO3 (BF-BT) capacitor exhibits a total energy density of 43.5 J cm-3 and an efficiency of 66.7% and maintains good energy storage performance over a wide temperature range (20-200 °C) and under large bending deformation (bending radii ≈ 2 mm). This study provides a feasible approach to improve the energy storage characteristics of dielectric oxide films and paves the way for their practical application in high-energy density capacitors.

2.
J Phys Chem A ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38954640

ABSTRACT

Machine learning is capable of effectively predicting the potential energies of molecules in the presence of high-quality data sets. Its application in the construction of ground- and excited-state potential energy surfaces is attractive to accelerate nonadiabatic molecular dynamics simulations of photochemical reactions. Because of the huge computational cost of excited-state electronic structure calculations, the construction of a high-quality data set becomes a bottleneck. In the present work, we first built two data sets. One was obtained from surface hopping dynamics simulations at the semiempirical OM2/MRCI level. Another was extracted from the dynamics trajectories at the CASSCF level, which was reported previously. The ground- and excited-state potential energy surfaces of ethylene-bridged azobenzene at the CASSCF computational level were constructed based on the former low-level data set. Although non-neural network machine learning methods can achieve good or modest performance during the training process, only neural network models provide reliable predictions on the latter external test data set. The BPNN and SchNet combined with the Δ-ML scheme and the force term in the loss functions are recommended for dynamics simulations. Then, we performed excited-state dynamics simulations of the photoisomerization of ethylene-bridged azobenzene on machine learning potential energy surfaces. Compared with the lifetimes of the first excited state (S1) estimated at different computational levels, our results on the E isomer are in good agreement with the high-level estimation. However, the overestimation of the Z isomer is unimproved. It suggests that smaller errors during the training process do not necessarily translate to more accurate predictions on high-level potential energies or better performance on nonadiabatic dynamics simulations, at least in the present case.

3.
Article in English | MEDLINE | ID: mdl-38957995

ABSTRACT

Background: The objective of this study was to investigate the association between pre-operative body mass index (BMI) and surgical infection in perihilar cholangiocarcinoma (pCCA) patients treated with curative resection. Methods: Consecutive pCCA patients were enrolled from four tertiary hospitals between 2008 and 2022. According to pre-operative BMI, the patients were divided into three groups: low BMI (≤18.4 kg/m2), normal BMI (18.5-24.9 kg/m2), and high BMI (≥25.0 kg/m2). The incidence of surgical infection among the three groups was compared. Multivariable logistic regression models were used to determine the independent risk factors associated with surgical infection. Results: A total of 371 patients were enrolled, including 283 patients (76.3%) in the normal BMI group, 30 patients (8.1%) in the low BMI group, and 58 patients (15.6%) in the high BMI group. The incidence of surgical infection was significantly higher in the patients in the low BMI and high BMI groups than in the normal BMI group. The multivariable logistic regression model showed that low BMI and high BMI were independently associated with the occurrence of surgical infection. Conclusions: The pCCA patients with a normal BMI treated with curative resection could have a lower risk of surgical infection than pCCA patients with an abnormal BMI.

4.
Int J Surg ; 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38980664

ABSTRACT

BACKGROUND: We aimed to use preoperative computed tomography images to develop a radiomic nomogram to select patients who would benefit from spleen-preserving splenic hilar (No.10) lymphadenectomy (SPSHL). METHODS: A pooled analysis of three distinct prospective studies was performed. The splenic hilar lymph node (SHLN) ratio (sLNR) was established as the quotient of the number of metastatic SHLN to the total number of SHLN. Radiomic features reflecting the phenotypes of the primary tumor (RS1) and SHLN region (RS2) were extracted and used as predictive factors for sLNR. RESULTS: This study included 733 patients: 301 in the D2 group and 432 in the D2+No.10 group. The optimal sLNR cutoff value was set at 0.4, and the D2+No.10 group was divided into three groups: sLNR=0, sLNR≤0.4, and sLNR>0.4. Patients in the D2+No. 10 group were randomly divided into the training (n=302) and validation (n=130) cohorts. The AUCs value of the nomogram, including RS1 and RS2, were 0.952 in the training cohort and 0.888 in the validation cohort. The entire cohort was divided into three groups based on the nomogram scores: low, moderate and high SHLN metastasis burden groups (LMB, MMB and HMB, respectively). A similar 5-year OS rate was found between the D2 and D2+No. 10 groups in the LMB and HMB groups. In the MMB group, the 5-year OS of the D2+No. 10 group (73.4%) was significantly higher than that of the D2 group (37.6%) (P<0.001). CONCLUSIONS: The nomogram showed good predictive ability for distinguishing patients with various SHLN metastasis burdens. It can accurately identify patients who would benefit from SPSHL.

5.
Phys Rev Lett ; 132(24): 246503, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38949334

ABSTRACT

Novel critical phenomena beyond the Landau-Ginzburg-Wilson paradigm have been long sought after. Among many candidate scenarios, the deconfined quantum critical point (DQCP) constitutes the most fascinating one, and its lattice model realization has been debated over the past two decades. Here we apply the spherical Landau level regularization upon the exact (2+1)D SO(5) nonlinear sigma model with a topological term to study the potential DQCP therein. We perform a density matrix renormalization group (DMRG) simulation with SU(2)_{spin}×U(1)_{charge}×U(1)_{angular-momentum} symmetries explicitly implemented. Using crossing point analysis for the critical properties of the DMRG data, accompanied by quantum Monte Carlo simulations, we accurately obtain the comprehensive phase diagram of the model and find various novel quantum phases, including Néel, ferromagnet (FM), valence bond solid (VBS), valley polarized (VP) states and a gapless quantum disordered phase occupying an extended area of the phase diagram. The VBS-disorder and Néel-disorder transitions are continuous with non-Wilson-Fisher exponents. Our results show the VBS and Néel states are separated by either a weakly first-order transition or the disordered region with a multicritical point in between, thus opening up more interesting questions on the two-decade long debate on the nature of the DQCP.

6.
World J Surg Oncol ; 22(1): 180, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38987785

ABSTRACT

PURPOSE: To address this evidence gap and validate short-term OS at less than 5 years as a reliable surrogate endpoint for 5-year OS. METHODS: We analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database, focusing on non-metastatic NPC patients diagnosed between 2010 and 2015. Patients were categorized into radiotherapy and chemoradiotherapy groups. RESULTS: This retrospective study examined 2,047 non-metastatic NPC patients. Among them, 217 received radiotherapy, and 1,830 received chemoradiotherapy. Our analysis results indicated that the 4-year OS may serve as a reliable surrogate endpoint for patients with AJCC clinical stage I (80 vs. 78%, P = 0.250), regardless of the treatment received. Specifically, in the radiotherapy group, patients with stage I, T0-T1, and N0 NPC showed similar OS rates at 4 and 5 years (83 vs. 82%, P = 1.000; 78 vs. 76%, P = 0.250; 78 vs. 77%, P = 0.500, respectively). Similarly, patients with stage II-IV, T2-T4, and N1-3 NPC showed no significant difference in OS rates between 3 and 5 years (57 vs. 51%, P = 0.063; 52 vs. 46%, P = 0.250; 54 vs. 46%, P = 0.125, respectively) in the radiotherapy group. In the chemoradiotherapy group, only the 3-year OS rate did not significantly differ from that at 5 years in stage I patients (79vs. 72%, P = 0.063). CONCLUSIONS: Our study suggests that short-term surrogate endpoints may be valuable for evaluating 5-year OS outcomes in NPC patients in non-endemic areas.


Subject(s)
Chemoradiotherapy , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms , Neoplasm Staging , Humans , Female , Male , Retrospective Studies , Middle Aged , Nasopharyngeal Carcinoma/therapy , Nasopharyngeal Carcinoma/pathology , Nasopharyngeal Carcinoma/mortality , Survival Rate , Chemoradiotherapy/methods , Chemoradiotherapy/mortality , Nasopharyngeal Neoplasms/therapy , Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/mortality , Follow-Up Studies , Prognosis , Adult , SEER Program/statistics & numerical data , Aged , Young Adult
7.
Pestic Biochem Physiol ; 202: 105952, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38879306

ABSTRACT

The citrus red mite, Panonychus citri, is one of the most notorious and devastating citrus pests around the world that has developed resistance to multiple chemical acaricides. In previous research, we found that spirodiclofen-resistant is related to overexpression of P450, CCE, and ABC transporter genes in P. citri. However, the regulatory mechanisms of these detoxification genes are still elusive. This study identified all hormone receptor 96 genes of P. citri. 8 PcHR96 genes contained highly conserved domains. The expression profiles showed that PcHR96h was significantly upregulated in spirodiclofen resistant strain and after exposure to spirodiclofen. RNA interference of PcHR96h decreased expression of detoxification genes and increased spirodiclofen susceptibility in P. citri. Furthermore, molecular docking, heterologous expression, and drug affinity responsive target stability demonstrated that PcHR96h can interact with spirodiclofen in vitro. Our research results indicate that PcHR96h plays an important role in regulating spirodiclofen susceptibility and provides theoretical support for the resistance management of P. citri.


Subject(s)
Spiro Compounds , Animals , Spiro Compounds/pharmacology , Spiro Compounds/metabolism , Acaricides/pharmacology , Propionates/pharmacology , Propionates/metabolism , Tetranychidae/drug effects , Tetranychidae/genetics , Tetranychidae/metabolism , Molecular Docking Simulation , Arthropod Proteins/genetics , Arthropod Proteins/metabolism , Drug Resistance/genetics , 4-Butyrolactone/analogs & derivatives
9.
Huan Jing Ke Xue ; 45(6): 3352-3362, 2024 Jun 08.
Article in Chinese | MEDLINE | ID: mdl-38897757

ABSTRACT

This study explored the characteristics of spatial and temporal changes in drought in the Yellow River Basin from 2001 to 2020 based on TVPDI, surface runoff, vegetation net primary productivity, and grain yield data. Further, the effects of drought on water resources, grain resources, and vegetation resources were also analyzed using data spatialization methods, slope trend analysis, and Pearson correlation analysis. The results showed that:① The spatial distribution of drought in the Yellow River basin was stepped from southeast to northwest, and 60.6 % of the basin was in drought. The overall trend of drought in the basin was decreasing annually, and 94 % of the basin was gradually changing from drought to wet conditions, and the trend of drought from spring to winter decreased first and then increased. ② From the spatial and temporal changes in important resources in the basin, 53 % of the key surface runoff areas showed an increasing trend and were mainly located in the southwest of the basin; the net primary productivity (NPP) of vegetation and grain yield of food resources also showed an increasing trend. ③ Drought and the three types of resources showed significant spatial correlations, and the higher the degree of drought, the more significant the effects on surface runoff, vegetation productivity, and grain yield. However, the important resources in areas that had become wetter in recent years had not increased significantly, which indicated that the effects of drought on the three types of important resources had a time lag, and their lags had significant differences in spatial distribution and geographical differentiation patterns. This study has important theoretical implications for agricultural production, drought mitigation, and ecological conservation in the Yellow River Basin.

10.
World J Clin Cases ; 12(16): 2713-2721, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38899303

ABSTRACT

BACKGROUND: Photoaging, a result of chronic sun exposure, leads to skin damage and pigmentation changes. Traditional treatments may have limitations in high-altitude areas like Yunnan Province. Intradermal Col Ι injections stimulate collagen production, potentially improving skin quality. This study aims to assess the efficacy and safety of this treatment for photoaging. AIM: To evaluate the efficacy and safety of intradermal type Ι collagen (Col Ι) injection for treating photoaging. METHODS: This prospective, self-controlled study investigated the impact of intradermal injections of Col Ι on skin photodamage in 20 patients from the Yunnan Province. Total six treatment sessions were conducted every 4 wk ± 3 d. Before and after each treatment, facial skin characteristics were quantified using a VISIA skin detector. Skin thickness data were assessed using the ultrasound probes of the Dermalab skin detector. The Face-Q scale was used for subjective evaluation of the treatment effect by the patients. RESULTS: The skin thickness of the right cheek consistently increased after each treatment session compared with baseline. The skin thickness of the left cheek significantly increased after the third through sixth treatment sessions compared with baseline. The skin thickness of the right zygomatic region increased after the second to sixth treatment sessions, whereas that of the left zygomatic region showed a significant increase after the fourth through sixth treatment sessions. The skin thickness of both temporal regions significantly increased after the fifth and sixth treatment sessions compared with baseline (P < 0.05). These findings were also supported by skin ultrasound images. The feature count for the red areas and wrinkle feature count decreased following the treatment (P < 0.05). VISIA assessments also revealed a decrease in the red areas after treatment. The Face-Q-Satisfaction with Facial Appearance Overall and Face-Q-Satisfaction with Skin scores significantly increased after each treatment session. The overall appearance of the patients improved after treatment. CONCLUSION: Intradermal Col Ι injection improves photoaging, with higher patient satisfaction and fewer adverse reactions, and could be an effective treatment method for populations residing in high-altitude areas.

11.
PhytoKeys ; 242: 161-227, 2024.
Article in English | MEDLINE | ID: mdl-38854497

ABSTRACT

This study addresses the longstanding absence of a comprehensive phylogenetic backbone for the apple tribe Maleae, a deficiency attributed to limited taxon and marker sampling. We conducted an extensive taxon sampling, incorporating 563 plastomes from a diverse range of 370 species encompassing 26 presently recognized genera. Employing a range of phylogenetic inference methods, including RAxML and IQ-TREE2 for Maximum Likelihood (ML) analyses, we established a robust phylogenetic framework for the Maleae tribe. Our phylogenomic investigations provided compelling support for three major clades within Maleae. By integrating nuclear phylogenetic data with morphological and chromosomal evidence, we propose an updated infra-tribal taxonomic system, comprising subtribe Malinae Reveal, subtribe Lindleyinae Reveal, and subtribe Vauqueliniinae B.B.Liu (subtr. nov.). Plastid phylogenetic analysis also confirmed the monophyly of most genera, except for Amelanchier, Malus, Sorbus sensu lato, and Stranvaesia. In addition, we present a comprehensive taxonomic synopsis of Photinia and its morphological allies in the Old World, recognizing 27 species and ten varieties within Photinia, three species and two varieties within Stranvaesia, and two species and three varieties within Weniomeles. Furthermore, we also lectotypified 12 names and made two new combinations, Photiniamicrophylla (J.E.Vidal) B.B.Liu and Weniomelesatropurpurea (P.L.Chiu ex Z.H.Chen & X.F.Jin) B.B.Liu.

12.
Anal Chim Acta ; 1312: 342780, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38834272

ABSTRACT

BACKGROUND: The convenient preparation and application of functionalized organic-inorganic hybrid monolithic materials have obtained substantial interest in the pretreatment of complex samples by solid-phase extraction (SPE). Compared to the in-tube solid-phase microextraction in fused-silica capillaries, micro SPE in plastic pipette tips have fascinating merits for the easily operated enrichment of trace target analytes from biological samples. However, the poor compatibility of organic-inorganic hybrid monoliths with plastics leads to the rare appearance of commercial hybrid monolithic pipette tips (HMPTs). Therefore, how to synthesize the organic-inorganic hybrid monolithic materials with better extraction performance in plastic pipette tips becomes a challenge. RESULTS: We develop a facile and cheap strategy to immobilize organic-inorganic hybrid monoliths in pipette tips. Melamine sponge was employed as the supporting skeleton to in situ assemble amine- and thiol-bifunctionalized hybrid monolithic material via "one pot" in a pipette tip, and gold nanoparticles (GNPs) and thiol-modified aptamer against human α-thrombin were sequentially attached to the hybrid monolith within the HMPTs. The average coverage density of the aptamer with GNPs as an intermediary reached as high as 818.5 pmol µL-1. The enriched thrombin concentration was determined by a sensitive enzymatic chromogenic assay with the limit of detection of 2 nM. The extraction recovery of thrombin at 10 nM in human serum was 86.1 % with a relative standard deviation of 6.1 %. This proposed protocol has been applied to the enrichment and determination of thrombin in real serum sample with strong anti-interference ability, low limit of detection and high recovery. SIGNIFICANCE: The amine- and thiol-bifunctionalized HMPTs prepared with sponge as the skeleton frame provided a novel substrate material to decorate aptamers for efficient enrichment of proteins. This enlightens us that we can take advantage of the tunability of sponge assisted HMPTs to produce and tailor a variety of micro SPE pipette tips for broader applications on the analysis of trace targets in complex biological, clinic and environmental samples.


Subject(s)
Aptamers, Nucleotide , Thrombin , Triazines , Triazines/chemistry , Triazines/isolation & purification , Aptamers, Nucleotide/chemistry , Humans , Thrombin/analysis , Thrombin/isolation & purification , Gold/chemistry , Metal Nanoparticles/chemistry , Solid Phase Extraction/methods
13.
Phys Rev Lett ; 132(23): 236502, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38905653

ABSTRACT

Integer and fractional Chern insulators have been extensively explored in correlated flat band models. Recently, the prediction and experimental observation of fractional quantum anomalous Hall (FQAH) states with spontaneous time-reversal symmetry breaking have garnered attention. While the thermodynamics of integer quantum anomalous Hall (IQAH) states have been systematically studied, our theoretical knowledge on thermodynamic properties of FQAH states has been severely limited. Here, we delve into the general thermodynamic response and collective excitations of both IQAH and FQAH states within the paradigmatic flat Chern-band model with remote band considered. Our key findings include (i) in both ν=1 IQAH and ν=1/3 FQAH states, even without spin fluctuations, the charge-neutral collective excitations would lower the onset temperature of these topological states, to a value significantly smaller than the charge gap, due to band mixing and multiparticle scattering; (ii) by employing large-scale thermodynamic simulations in FQAH states in the presence of strong interband mixing between C=±1 bands, we find that the lowest collective excitations manifest as the zero-momentum excitons in the IQAH state, whereas in the FQAH state, they take the form of magnetorotons with finite momentum; (iii) the unique charge oscillations in FQAH states are exhibited with distinct experimental signatures, which we propose to detect in future experiments.

14.
Oncologist ; 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38907674

ABSTRACT

BACKGROUND: Tumor microenvironment (TME) characteristics including tumor stroma ratio (TSR), tumor budding (TB), and tumor-infiltrating lymphocytes (TILs) were examined in resected gastric cancer. These TME features have been shown to indicate metastatic potential in colon cancer, and intestinal-type gastric cancer (IGC) has pathological similarities with that malignancy. METHODS: TSR, TB, and TILs were quantified in routine histological sections from 493 patients with IGC who underwent radical resection at 2 university hospitals in China from 2010 to 2016. TME variables were dichotomized as follows: TSR (50%), TILs (median), TB per international guidelines (4 buds/0.785mm2), and platelet-lymphocyte ratio (PLR) per survival ROC. Association of TME features with patient clinicopathological characteristics, time-to-recurrence (TTR), and cancer-specific-survival (CSS) were examined using univariate and multivariate analysis, including a relative contribution analysis by Cox regression. RESULTS: Patients whose tumors showed high TSR or high TB or low TILs were each significantly associated with increased T and N stage, higher histological grade, and poorer TTR and CSS at 5 years. Only TSR and N stage were independently associated with TTR and CSS after adjustment for covariates. PLR was only independently associated with TTR after adjustment for covariates. Among the variables examined, only TSR was significantly associated with both TTR (HR 1.72, 95% CI, 1.14-2.60, P = .01) and CSS (HR 1.62, 95% CI, 1.05-2.51, P = .03) multivariately. Relative contribution to TTR revealed that the top 3 contributors were N stage (45.1%), TSR (22.5%), and PLR (12.9%), while the top 3 contributors to CSS were N stage (59.9%), TSR (14.7%), and PLR (10.9%). CONCLUSIONS: Among the examined TME features, TSR was the most robust for prognostication and was significantly associated with both TTR and CSS. Furthermore, the relative contribution of TSR to patient TTR and CSS was second only to nodal status.

17.
Int J Med Sci ; 21(6): 1079-1090, 2024.
Article in English | MEDLINE | ID: mdl-38774751

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a rare, chronic and progressively worsening lung disease that poses a significant threat to patient prognosis, with a mortality rate exceeding that of some common malignancies. Effective methods for early diagnosis and treatment remain for this condition are elusive. In our study, we used the GEO database to access second-generation sequencing data and associated clinical information from IPF patients. By utilizing bioinformatics techniques, we identified crucial disease-related genes and their biological functions, and characterized their expression patterns. Furthermore, we mapped out the immune landscape of IPF, which revealed potential roles for novel kinase 1 and CD8+T cells in disease progression and outcome. These findings can aid the development of new strategies for the clinical diagnosis and treatment of IPF.


Subject(s)
CD8-Positive T-Lymphocytes , Idiopathic Pulmonary Fibrosis , Humans , Idiopathic Pulmonary Fibrosis/genetics , Idiopathic Pulmonary Fibrosis/immunology , Idiopathic Pulmonary Fibrosis/pathology , Idiopathic Pulmonary Fibrosis/drug therapy , CD8-Positive T-Lymphocytes/immunology , Computational Biology , Disease Progression , Prognosis
18.
Int J Surg ; 2024 May 22.
Article in English | MEDLINE | ID: mdl-38775618

ABSTRACT

BACKGROUND: Learning curves have been used in the field of RG. However, it should be noted that the previous study did not comprehensively investigate all changes related to the learning curve.This study aims to establish a learning curve for radical robotic gastrectomy (RG) and evaluate its effect on the short-term outcomes of patients with gastric cancer. METHODS: The clinicopathological data of 527 patients who underwent RG between August 2016 and June 2021 were retrospectively analyzed. Learning curves related to the operation time and postoperative hospital stay were determined separately using cumulative sum (CUSUM) analysis. Then, the impact of the learning curve on surgical efficacy was analyzed. RESULTS: Combining the CUSUM curve break points and technical optimization time points, the entire cohort was divided into three phases (patients 1-100, 101-250, and 251-527). The postoperative complication rate and postoperative recovery time tended to decrease significantly with phase advancement (P<0.05). More extraperigastric examined lymph nodes (LN) were retrieved in phase III than in phase I (I vs. III, 15.12±6.90 vs. 17.40±7.05, P=0.005). The rate of LN noncompliance decreased with phase advancement. Textbook outcome (TO) analysis showed that the learning phase was an independent factor in TO attainment (P<0.05). CONCLUSION: With learning phase advancement, the short-term outcomes were significantly improved. It is possible that our optimization of surgical procedures could have contributed to this improvement. The findings of this study facilitate the safe dissemination of RG in the minimally invasive era.

20.
J Comput Chem ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38742401

ABSTRACT

We show herein that 1,10-dicyano substitution restricts the paragon fluxionality of bullvalene to just 14 isomers which isomerize along a single cycle. The restricted fluxionality of 1,10-dicyanobullvalene (DCB) is investigated by means of: (i) Bonding analyses of the isomer structures using the adaptive natural density partitioning (AdNDP). (ii) Quantum dynamical simulations of the isomerizations along the cyclic intrinsic reaction coordinate of the potential energy surface (PES). The PES possesses 14 equivalent potential wells supporting 14 isomers which are separated by 14 equivalent potential barriers supporting 14 transition states. Accordingly, at low temperatures, DCB appears as a hindered molecular rotor, without any delocalization of the wavefunction in the 14 potential wells, without any nuclear spin isomers, and with completely negligible tunneling. These results are compared and found to differ from those for molecular boron rotors. (iii) Born-Oppenheimer molecular dynamics (BOMD) simulations of thermally activated isomerizations. (iv) Calculations of the rate constants in the frame of transition state theory (TST) with reasonable agreement achieved with the BOMD results. (v) Simulations of the equilibration dynamics using rate equations for the isomerizations with TST rate coefficients. Accordingly, in the long-time limit, isomerizations of the 14 isomers, each with Cs symmetry, approach the "14 Cs → C7v" thermally averaged structure. This is a superposition of the 14 equally populated isomer structures with an overall C7v symmetry. By extrapolation, the results for DCB yield working hypotheses for so far un-explored properties e.g. for the equilibration dynamics of C10H10.

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