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1.
J Neurovirol ; 29(5): 555-563, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37400732

RESUMO

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic disabling disease. However, there is a lack of an adequate and specific health measurement instrument validated and with good performance to assess their degree of physical disability. This led us to carry out this study and to evaluate the performance of Fiocruz's National Institute of Infectious Diseases (IDS) disability scale, a specific instrument for HAM/TSP. Ninety-two HAM/TSP patients participated in the study. One researcher applied the IDS, IPEC scale, Disability Status Scale (DSS), Expanded DSS (EDSS), Osame scale, Beck Depression Inventory, and the WHOQOL-BREF questionnaire. In parallel, blindly, and separately, other researchers applied the IDS. An inter-rater reliability analysis of the IDS, correlation analysis with the other scales, and depression and quality of life questionnaires were performed. The applicability of the IDS was also evaluated. The IDS showed high reliability in all scores. The inter-rater reliability test for the total IDS score was 0.94 (0.82-0.98) on its four dimensions. The scale adequately indicated the different degrees of disability, presenting a distribution similar to normal. There was a high correlation with the other scales (Spearman coefficients > 0.80, p < 0.001). The scale had good acceptance among users and a short application time. IDS for HAM/TSP was reliable, consistent, easy, and fast to use. It can be used for both prospective evaluations and clinical trials. The present study supports the IDS as a valid instrument to measure disability in patients with HAM/TSP compared to previously used scales.


Assuntos
Doenças Transmissíveis , Vírus Linfotrópico T Tipo 1 Humano , Paraparesia Espástica Tropical , Humanos , Paraparesia Espástica Tropical/diagnóstico , Reprodutibilidade dos Testes , Qualidade de Vida
2.
J Chem Phys ; 159(19)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37966005

RESUMO

We report experimental differential cross sections (DCSs) for electron impact excitation of bands I to V of benzene at incident energies of 10, 12.5, 15, and 20 eV. They are compared to calculations using the Schwinger multichannel method while accounting for up to 437 open channels. For intermediate scattering angles, the calculations reveal that the most intense band (V) emerges from surprisingly similar contributions from all its underlying states (despite some preference for the dipole-allowed transitions). They further shed light on intricate multichannel couplings between the states of bands I to V and higher-lying Rydberg states. In turn, the measurements support a vibronic coupling mechanism for excitation of bands II and IV and also show an unexpected forward peak in the spin-forbidden transition accounting for band III. Overall, there is decent agreement between theory and experiment at intermediate angles and at lower energies and in terms of the relative DCSs of the five bands. Discrepancies between the present and previous experiment regarding bands IV and V draw attention to the need of additional experimental investigations. We also report measured DCSs for vibrational excitation of combined C-H stretching modes.

3.
Pract Neurol ; 21(3): 241-242, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33627490

RESUMO

Sporothrix brasiliensis usually causes infection limited to the skin, subcutaneous tissue and regional lymph nodes. Contamination occurs through inhalation or accidental inoculation from animal scratches and bites. Meningitis is rare and mostly occurs in immunosuppressed patients. Here, we describe an immunocompetent person who developed chronic meningitis and discuss the diagnosis, differential diagnosis and treatment of this rare condition.


Assuntos
Meningite , Sporothrix , Esporotricose , Animais , Humanos , Masculino , Pessoa de Meia-Idade , Pele , Esporotricose/diagnóstico
4.
J Neurovirol ; 26(6): 941-944, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33006717

RESUMO

COVID-19 pandemic revealed several neurological syndromes related to this infection. We describe the clinical, laboratory, and radiological features of eight patients with COVID-19 who developed peripheral facial palsy during infection. In three patients, facial palsy was the first symptom. Nerve damage resulted in mild dysfunction in five patients and moderate in three. SARS-Cov-2 was not detected in CSF by PCR in any of the samples. Seven out of eight patients were treated with steroids and all patients have complete or partial recovery of the symptoms. Peripheral facial palsy should be added to the spectrum of neurological manifestations associated with COVID-19.


Assuntos
COVID-19/complicações , Paralisia Facial/virologia , Adulto , Anti-Inflamatórios/uso terapêutico , Nervo Facial/patologia , Paralisia Facial/tratamento farmacológico , Feminino , Humanos , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Prednisona/uso terapêutico , SARS-CoV-2
5.
Chemphyschem ; 21(16): 1814-1825, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32579732

RESUMO

In this study, a homogeneous thin film growth of pentacene onto indium tin oxide (ITO) coated glass surfaces is explored using a high-resolution and reproducible vapor deposition methodology. Moreover, vacuum thermal evaporation of ionic liquids (ILs) ([C2 C1 im][NTf2 ] and [C2 C1 im][OTF]) onto ITO, gold/palladium (AuPd) and pentacene surfaces were performed. A greater wettability behavior of ILs is observed for surfaces containing AuPd. Sequential and simultaneous depositions of ILs and pentacene were explored. Simultaneous depositions lead to the formation of nanocomposites films, consisting of IL micro- and nanodroplets covered by pentacene layers. Plasma surface treatment was used to induce the ILs droplets coalescence and explore the dynamics and phase separation of the nanocomposites. The [C2 C1 im][OTF] droplets were found to be completely covered with pentacene, which suggests a great affinity between cation-anion pairs and the aromatic moiety. Pentacene films and their nanocomposites with ILs exhibit a typical optical band gap of Egap =1.77 eV, indicating that the nanocomposite phase domains are large enough to behavior as the bulk.

6.
Cephalalgia ; 40(13): 1452-1458, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33146040

RESUMO

BACKGROUND: Headache is a frequent complaint in COVID-19 patients. However, no detailed information on headache characteristics is provided in these reports. Our objective is to describe the characteristics of headache and the cerebrospinal fluid (CSF) profile in COVID-19 patients, highlighting the cases of isolated intracranial hypertension. METHODS: In this cross-sectional study, we selected COVID-19 patients who underwent lumbar puncture due to neurological complaints from April to May 2020. We reviewed clinical, imaging, and laboratory data of patients with refractory headache in the absence of other encephalitic or meningitic features. CSF opening pressures higher than 250 mmH2O were considered elevated, and from 200 to 250 mmH2O equivocal. RESULTS: Fifty-six COVID-19 patients underwent lumbar puncture for different neurological conditions. A new, persistent headache that prompted a CSF analysis was diagnosed in 13 (23.2%). The pain was throbbing, holocranial or bilateral in the majority of patients. All patients had normal CSF analysis and RT-qPCR for SARS-CoV-2 was negative in all samples. Opening pressure >200 mmH2O was present in 11 patients and, in six of these, > 250 mmH2O. 6/13 patients had complete improvement of the pain, five had partial improvement, and two were left with a daily persistent headache. CONCLUSIONS: In a significant proportion of COVID-19 patients, headache was associated to intracranial hypertension in the absence of meningitic or encephalitic features. Coagulopathy associated with COVID-19 could be an explanation, but further studies including post-mortem analysis of areas of production and CSF absorption (choroid plexuses and arachnoid granulations) are necessary to clarify this issue.


Assuntos
Infecções por Coronavirus/complicações , Hipertensão Intracraniana/virologia , Pneumonia Viral/complicações , Adulto , Idoso , Betacoronavirus , COVID-19 , Pressão do Líquido Cefalorraquidiano , Infecções por Coronavirus/líquido cefalorraquidiano , Estudos Transversais , Feminino , Cefaleia/líquido cefalorraquidiano , Cefaleia/etiologia , Humanos , Hipertensão Intracraniana/líquido cefalorraquidiano , Hipertensão Intracraniana/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/líquido cefalorraquidiano , Estudos Retrospectivos , SARS-CoV-2 , Punção Espinal
7.
J Chem Phys ; 152(24): 244302, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32610975

RESUMO

We report computed differential cross sections (DCSs) for electron impact excitation of the lower-lying states of both trans and gauche tautomers of ethanol, as well as total cross sections for the 15 eV-50 eV energy range. The Schwinger multichannel (SMC) method with pseudopotentials has been employed, and in our most sophisticated calculation in terms of multichannel coupling, 431 open target states have been considered. We found an overall good agreement with the available experimental data at intermediate scattering angles and at higher impact energies. Although we have used a Born-closure scheme for the higher partial waves, we have found discrepancies in the forward direction that were assigned to a poor description of the long-range component of the lower partial waves. Meanwhile, the lack of more Rydberg states could be related to the overestimated DCSs at lower energies. Missing open channels are usually evoked to explain the remaining discrepancies to experiment, but here, we argue that other factors should also be involved. Aiming at an improved description of the target states, we have proposed a simple procedure for selecting the pairs of hole and particle orbitals while keeping the single excitation prescription of the current SMC implementation. A quantitative assessment of the collision process should further consider the individual contribution of each tautomer, which presented quite distinct DCSs in some cases. Our computed excitation energies also support that the second absorption band of ethanol is comprised of three singlet states of each tautomer, rather than the previously suggested two or four states.

9.
J Chem Phys ; 144(12): 124310, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-27036451

RESUMO

We report on integral-, momentum transfer- and differential cross sections for elastic and electronically inelastic electron collisions with furfural (C5H4O2). The calculations were performed with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (N(open)) at either the static-exchange (N(open) ch-SE) or the static-exchange-plus-polarisation (N(open) ch-SEP) approximation was employed to calculate the scattering amplitudes at impact energies lying between 5 eV and 50 eV, using a channel coupling scheme that ranges from the 1ch-SEP up to the 63ch-SE level of approximation depending on the energy considered. For elastic scattering, we found very good overall agreement at higher energies among our SMCPP cross sections, our IAM-SCAR+I cross sections and the experimental data for furan (a molecule that differs from furfural only by the substitution of a hydrogen atom in furan with an aldehyde functional group). This is a good indication that our elastic cross sections are converged with respect to the multichannel coupling effect for most of the investigated intermediate energies. However, although the present application represents the most sophisticated calculation performed with the SMCPP method thus far, the inelastic cross sections, even for the low lying energy states, are still not completely converged for intermediate and higher energies. We discuss possible reasons leading to this discrepancy and point out what further steps need to be undertaken in order to improve the agreement between the calculated and measured cross sections.

10.
J Chem Phys ; 142(10): 104304, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-25770537

RESUMO

We report theoretical and experimental total cross sections for electron scattering by phenol (C6H5OH). The experimental data were obtained with an apparatus based in Madrid and the calculated cross sections with two different methodologies, the independent atom method with screening corrected additivity rule (IAM-SCAR), and the Schwinger multichannel method with pseudopotentials (SMCPP). The SMCPP method in the Nopen-channel coupling scheme, at the static-exchange-plus-polarization approximation, is employed to calculate the scattering amplitudes at impact energies ranging from 5.0 eV to 50 eV. We discuss the multichannel coupling effects in the calculated cross sections, in particular how the number of excited states included in the open-channel space impacts upon the convergence of the elastic cross sections at higher collision energies. The IAM-SCAR approach was also used to obtain the elastic differential cross sections (DCSs) and for correcting the experimental total cross sections for the so-called forward angle scattering effect. We found a very good agreement between our SMCPP theoretical differential, integral, and momentum transfer cross sections and experimental data for benzene (a molecule differing from phenol by replacing a hydrogen atom in benzene with a hydroxyl group). Although some discrepancies were found for lower energies, the agreement between the SMCPP data and the DCSs obtained with the IAM-SCAR method improves, as expected, as the impact energy increases. We also have a good agreement among the present SMCPP calculated total cross section (which includes elastic, 32 inelastic electronic excitation processes and ionization contributions, the latter estimated with the binary-encounter-Bethe model), the IAM-SCAR total cross section, and the experimental data when the latter is corrected for the forward angle scattering effect [Fuss et al., Phys. Rev. A 88, 042702 (2013)].

11.
J Chem Phys ; 141(5): 051105, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25106562

RESUMO

We report on the shape resonance spectra of phenol-water clusters, as obtained from elastic electron scattering calculations. Our results, along with virtual orbital analysis, indicate that the well-known indirect mechanism for hydrogen elimination in the gas phase is significantly impacted on by microsolvation, due to the competition between vibronic couplings on the solute and solvent molecules. This fact suggests how relevant the solvation effects could be for the electron-driven damage of biomolecules and the biomass delignification [E. M. de Oliveira et al., Phys. Rev. A 86, 020701(R) (2012)]. We also discuss microsolvation signatures in the differential cross sections that could help to identify the solvated complexes and access the composition of gaseous admixtures of these species.


Assuntos
Gases/química , Hidrogênio/química , Modelos Químicos , Modelos Moleculares , Fenol/química , Solventes/química , Água/química , Ânions/química , Sítios de Ligação , Simulação por Computador , Ligação de Hidrogênio
12.
Phys Chem Chem Phys ; 15(5): 1682-9, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23247550

RESUMO

We report elastic integral, differential and momentum transfer cross sections for low-energy electron scattering by the cellulose components ß-D-glucose and cellobiose (ß(1 → 4) linked glucose dimer), and the hemicellulose component ß-D-xylose. For comparison with the ß forms, we also obtain results for the amylose subunits α-D-glucose and maltose (α(1 → 4) linked glucose dimer). The integral cross sections show double peaked broad structures between 8 eV and 20 eV similar to previously reported results for tetrahydrofuran and 2-deoxyribose, suggesting a general feature of molecules containing furanose and pyranose rings. These broad structures would reflect OH, CO and/or CC σ* resonances, where inspection of low-lying virtual orbitals suggests significant contribution from anion states. Though we do not examine dissociation pathways, these anion states could play a role in dissociative electron attachment mechanisms, in case they were coupled to the long-lived π* anions found in lignin subunits [de Oliveira et al., Phys. Rev. A, 2012, 86, 020701(R)]. Altogether, the resonance spectra of lignin, cellulose and hemicellulose components establish a physical-chemical basis for electron-induced biomass pretreatment that could be applied to biofuel production.


Assuntos
Celulose/química , Polissacarídeos/química , Biomassa , Desoxirribose/química , Elétrons , Furanos/química , Modelos Químicos
14.
Lancet Oncol ; 12(13): 1229-39, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22094004

RESUMO

BACKGROUND: The epidemiological, prognostic, and therapeutic features of child and adolescent meningioma are poorly defined. Clinical knowledge has been drawn from small case series and extrapolation from adult studies. This study was done to pool and analyse the clinical evidence on child and adolescent meningioma. METHODS: Searches of PubMed, Medline, and Embase identified 35 case series of child and adolescent meningioma completed over the past 21 years. Individual patient data were obtained from 30 studies via direct communication with investigators. Primary outcomes were relapse-free survival (RFS) and overall survival. Prognostic variables were extent of initial surgery, use of upfront radiotherapy, age, sex, presence of neurofibromatosis, tumour location, and tumour grade. RFS and overall survival were analysed using Kaplan-Meier survival curves and multivariable Cox regression models. FINDINGS: From a total of 677 children and adolescents with meningioma, 518 were eligible for RFS analysis and 547 for overall survival analysis. Multivariable analysis showed that patients who underwent initial gross-total resection had better RFS (hazard ratio 0·16, 95% CI 0·10-0·25; p<0·0001) and overall survival (0·21, 0·11-0·39; p<0·0001) than those who had subtotal resection. No significant benefit was seen for upfront radiotherapy in terms of RFS (0·59, 0·30-1·16; p=0·128) or overall survival (1·10, 0·53-2·28; p=0·791). Patients with neurofibromatosis type 2 (NF2) had worse RFS than those without neurofibromatosis (2·36, 1·23-4·51; p=0·010). There was a significant change in overall survival with time between patients with NF2 compared with those without neurofibromatosis (1·45, 1·09-1·92; p=0·011); although overall survival was initially better for patients with NF2 than for those without neurofibromatosis, overall survival at 10 years was worse for patients with NF2. Patients with WHO grade III tumours had worse RFS than those with WHO grade I (3·90, 2·10-7·26; p<0·0001) and grade II tumours (2·49, 1·11-5·56; p=0·027). INTERPRETATION: Extent of initial surgical resection is the strongest independent prognostic factor for child and adolescent meningioma. No benefit for upfront radiotherapy was noted. Hence, aggressive surgical management, to achieve gross-total resection, is the initial treatment of choice. In the event of a subtotal resection, repeat resection is recommended to achieve maximum extirpation. Close observation is warranted for patients who have a subtotal resection or who have WHO grade III tumours. Patients without neurofibromatosis should have a minimum 10-year follow-up, whereas patients with NF2 should be considered a special risk category, necessitating life-long follow-up. FUNDING: None.


Assuntos
Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Procedimentos Neurocirúrgicos , Adolescente , Fatores Etários , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Neoplasias Meníngeas/mortalidade , Neoplasias Meníngeas/patologia , Meningioma/mortalidade , Meningioma/patologia , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/mortalidade , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Reoperação , Medição de Risco , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
15.
J Fungi (Basel) ; 9(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36675837

RESUMO

Meningeal sporotrichosis is rare and occurs predominantly in immunosuppressed individuals. This retrospective study explored clinical and laboratory characteristics, treatment, and prognosis of patients with disseminated sporotrichosis who underwent lumbar puncture (LP) at a Brazilian reference center from 1999 to 2020. Kaplan-Meier and Cox regression models were used to estimate overall survival and hazard ratios. Among 57 enrolled patients, 17 had meningitis. Fifteen (88.2%) had HIV infection, and in 6 of them, neurological manifestations occurred because of the immune reconstitution inflammatory syndrome (IRIS). The most frequent symptom was headache (88.2%). Meningeal symptoms at first LP were absent in 7/17 (41.2%) patients. Sporothrix was diagnosed in cerebrospinal fluid either by culture or by polymerase chain reaction in seven and four patients, respectively. All but one patient received prolonged courses of amphotericin B formulations, and seven received posaconazole, but relapses were frequent. Lethality among patients with meningitis was 64.7%, with a higher chance of death compared to those without meningitis (HR = 3.87; IC95% = 1.23;12.17). Meningeal sporotrichosis occurs mostly in people with HIV and can be associated with IRIS. Screening LP is indicated in patients with disseminated disease despite the absence of neurological complaints. Meningitis is associated with poor prognosis, and better treatment strategies are needed.

16.
Phys Rev Lett ; 107(10): 103201, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21981501

RESUMO

The mechanisms for multimode vibrational couplings in resonant positron annihilation are not well understood. We show that these resonances can arise from positron-induced distortions of the potential energy surface (target response to the positron field). Though these distortions can transfer energy into single- and multiquantum vibrations, they have so far been disregarded as a pathway to resonant annihilation. We also compare the existing annihilation theories and show that the currently accepted model can be cast as a special case of the Feshbach annihilation theory.

18.
J Chem Phys ; 132(12): 124309, 2010 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-20370125

RESUMO

The development of new alternative routes for production of second generation ethanol from sugarcane biomass poses a challenge to the scientific community. Current research in this field addresses the use of a plasma-based pretreatment of the lignocellulosic raw material. With the aim to provide a theoretical background for this experimental technique we investigate the role of low-energy electrons from the plasma in the rupture of the matrix of cellulosic chains. In this paper, we report calculated cross sections for elastic scattering of low-energy electrons by the alpha- and beta-D-glucose monomers. The calculations employed the Schwinger multichannel method with pseudopotentials and were carried out at the static-exchange and static-exchange plus polarization levels of approximation. Through the comparison of the results obtained with inclusion of polarization effects we discuss the influence of the different conformations of the hydroxyl group linked to the anomeric carbon on the resonance spectra of these molecules. Resonant structures appearing at different energies for alpha- and beta-glucose at the low-energy regime of impact energies can be understood as a fingerprint of an "isomeric effect" and suggest that distinct fragmentation mechanisms proceeding via sigma* shape resonances may become operative depending on the glucose anomer under consideration. For energies above 15 eV the integral elastic cross sections are very similar for both monomers. Differential cross sections for the glucopyranose anomers considered in this work are typically dominated by a strong forward scattering due to the molecules' large electric dipole moments and, for energies close to the resonances' positions, they display particular features at the intermediate angular region, notably a pronounced f-wave scattering pattern, that are probably associated with the presence of those structures.


Assuntos
Elétrons , Glucose/química , Carbono/química , Transferência de Energia , Isomerismo , Modelos Químicos , Análise Espectral , Termodinâmica
19.
J Chem Phys ; 132(20): 204301, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20515089

RESUMO

We report cross sections for low-energy elastic electron scattering by pyrrole, obtained with the Schwinger multichannel method implemented with pseudopotentials. Our calculations indicate pi( *) shape resonances in the B(1) and A(2) symmetries, and two sigma( *) resonances in the A(1) symmetry (the system belongs to the C(2v) point group). The present assignments of pi( *) resonances are very close to those previously reported for the isoelectronic furan molecule, in agreement with electron transmission spectra. The lowest-lying sigma( *) anion is localized on the N-H bond and provides a dissociation coordinate similar to those found in the hydroxyl groups of organic acids and alcohols. This sigma(NH) ( *) resonance overlaps the higher-lying pi( *) resonance (possibly both pi( *) states) and could give rise to direct and indirect dissociation pathways, which arise from electron attachment to sigma( *) and pi( *) orbitals, respectively. The photochemistry of pyrrole and 9-H adenine is similar, in particular with respect to the photostability mechanism that allows for the dissipation of the photon energy, and we believe pyrrole would also be a suitable prototype for studies of dissociative electron attachment (DEA) to DNA bases. We point out the connection between the mechanisms of photostability and DEA since both arise from the occupation of sigma( *) and pi( *) orbitals in neutral excited states and in anion states, respectively.


Assuntos
Elétrons/uso terapêutico , Fotoquímica/métodos , Pirróis/química , Simulação por Computador , DNA/química , Metabolismo Energético , Fótons/efeitos adversos , Fótons/uso terapêutico
20.
RSC Adv ; 10(20): 11766-11776, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35496587

RESUMO

The impact of structural differentiation between phenylcarbazoles (PhC, mCP, CBP, TCB) and phenylamines (TPA, BDB, TPB, TDAB) on the phase equilibria, optical spectrum, band gap, and thin-film morphology is evaluated and discussed. The carbazolyl units lead to a lower electronic conjugation contributing to a wide band gap when compared with the diphenylamine analogs. The fusion and sublimation equilibria indicate that entropic contribution is the key factor for the distinguished melting behavior and solid-phase volatility between phenylcarbazole derivatives and phenylamine analogs. The molecular differentiation between the two classes of compounds is not reflected in the crystal packing and intermolecular interactions. However, compared with the diphenylamino groups, the incorporation of carbazolyl moieties contributes to a less flexible molecule. Moreover, the results evidence that intermolecular bonding disruption along the fusion transition is more extensive for phenylamine derivatives. Due to the asymmetric nonplanar structure, mCP is characterized by a ratio of {T g/T m ≈ 3/4} while the more symmetric CBP and TCB molecules display ratios closer to {T g/T m ≈ 2/3}. Vapor-deposited thin films of mCP, CBP, and TCB are amorphous and their morphology is highly dependent on the substrate roughness. The lower flexibility of nonplanar phenylcarbazoles induces the formation of a glassy state due to the harder packing mechanism leading to the lower ability of the crystallization process.

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