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Nitroaromatic compounds are found in brown carbon aerosols emitted to the Earth's atmosphere by biomass burning, and are important organic chromophores for the absorption of solar radiation. Here, transient absorption spectroscopy spanning 100 fs-8 µs is used to explore the pH-dependent photochemical pathways for aqueous solutions of p-nitrophenol, chosen as a representative nitroaromatic compound. Broadband ultrafast UV-visible and infrared probes are used to characterize the excited states and intermediate species involved in the multistep photochemistry, and to determine their lifetimes under different pH conditions. The assignment of absorption bands, and the dynamical interpretation of our experimental measurements are supported by computational calculations. After 320 nm photoexcitation to the first bright state, which has 1ππ* character in the Franck-Condon region, and ultrafast (â¼200 fs) structural relaxation in the adiabatic S1 state to a region with 1nπ* electronic character, the S1 p-nitrophenol population decays on a time scale of â¼12 ps. This decay involves competition between direct internal conversion to the S0 state (â¼40%) and rapid intersystem crossing to the triplet manifold (â¼60%). Population in the T1-state decays by excited-state proton transfer (ESPT) to the surrounding water and relaxation of the resulting triplet-state p-nitrophenolate anion to its S0 electronic ground state in â¼5 ns. Reprotonation of the S0-state p-nitrophenolate anion recovers p-nitrophenol in its electronic ground state. Overall recovery of the S0 state of aqueous p-nitrophenol via these competing pathways is close to 100% efficient. The experimental observations help to explain why nitroaromatic compounds such as p-nitrophenol resist photo-oxidative degradation in the environment.
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Empyema necessitatis is a rare complication of an untreated or inadequately controlled empyema. We present the case of an 11-year-old female adolescent living in precarious conditions, overcrowding, incomplete vaccinations, irregular dental hygiene, and no significant family or personal medical history. The patient started with symptoms one week prior to her hospitalization, presenting a persistent sporadic dry cough, and was later diagnosed with complicated pneumonia, resulting in the placement of an endopleural tube. Vancomycin (40 mg/kg/day) and ceftriaxone (75 mg/kg/day) were administered. However, the clinical evolution was unfavorable, with fever and respiratory distress, so a right jugular catheter was placed. The CT scan showed a loculated collection that occupied the entire right lung parenchyma and pneumothorax at the right upper lobe level. After four days of treatment, the patient still presented purulent drainage with persistent right pleural effusion syndrome. P. melaninogenica and D. pneumosintes were identified from the purulent collection on the upper right lobe, so the antimicrobial treatment was adapted to a glycopeptide, Teicoplanin, at a weight-based dosing of 6 mg/kg/day and Metronidazole at a weight-based dosing of 30 mg/kg/day. In addition, VAC therapy was used for 26 days with favorable resolution.
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BACKGROUND: The primary objective of this study was to assess the frequency of body composition increases and their relationships to changes in body weight in two cohorts of real world, treatment-naïve, advanced non-small cell lung cancer (NSCLC) patients. One cohort received the current standard of care (CSOC), which consisted of immunotherapy and newer chemotherapy regimens, and the other cohort was treated with the former standard of care (FSOC), consisting only of older platinum-containing regimens. METHODS: CSOC (n = 106) and FSOC (n = 88) cohorts of advanced NSCLC patients were included in this study. Weights were collected at each clinical visit, and body composition analysis from routine chest computed tomography via automated segmentation software assessed at baseline and at 6 and 12 weeks. Standard statistical methods were used to calculate relationships between changes in weight and in body composition. RESULTS: The CSOC cohort contained 106 stage IV NSCLC patients treated between 16/12/2014 and 22/10/2020 while the FSOC cohort contained 88 stage III/IV NSCLC patients treated between 16/6/2006 and 18/11/2014. While each cohort exhibited decreases in median weight, body mass index (BMI), mean skeletal muscle index (SMI) and subcutaneous adipose tissue index (SATI) at the 6 and 12 week time points, a subset of patients experienced increases in these parameters. Using a threshold of ≥2.5% increase for weight, BMI, SMI, and SATI at the 12 week time point, both cohorts showed similar (20.5% and 27.3%) increases in these parameters. With a cut point of ≥5% increase at 12 weeks follow-up, 8.0% to 25.0% of the patients gained ≥5% in weight, BMI, SMI and SATI. Comparing these results in each cohort showed no significant differences. Pearson coefficients for weight change related to changes in SMI and SATI at 6 and 12 weeks ranged from 0.31 to 0.58 with all P values <0.02. Pearson coefficients for weight change at 12 weeks related to changes in VATI and IMATI ranged from 0.26 to 0.47 with all P values <0.05. Comparison of Pearson coefficients for each cohort showed no significant differences. CONCLUSIONS: Although decreases in median weight, BMI, SMI and SATI were observed in both cohorts, similar percentage of patients in each cohort experienced increases in these parameters. These findings, plus the positive correlations between longitudinal measurements of weight, muscle mass and adipose tissue, indicate that weight gain in these patients involves increases in both muscle mass and adipose tissue. Upon validation, these findings could have implications for clinical trial design and for translational research in cancer cachexia.
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An excellent agreement for simulated and measured absorption and emission spectra is found for four donor-acceptor aromatic molecules (tetraphenylpyrazine, tetraphenylethene, distirylanthracene and hexaphenylsilole) whose derivatives serve as solid state photosensitizers. After comparing several hybrid TDDFT functionals, EOM-CCSD, and experiments, the best agreement was found with TD-B3LYP and double zeta basis sets (6-31G** and def2-SVP) for one molecule in gas phase. A full characterisation of twelve to twenty electronic excited states was performed in every system. Symmetry-forbidden bands are found in the absorption spectra by sampling fifty to hundred geometries from a Wigner distribution. The density of states in the region 2-6â eV was also analysed, showing a very packed region of excited states and suggesting that dark electronic states may play a role in the dynamics of some of the photoexcited systems. Further calculations were done with QM/xTB at geometries extracted from previously published X-ray data to evaluate the influence of the environment on the excitations of the four aggregated molecular crystals.
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Background Gastrointestinal stromal tumors (GISTs) represent the most common mesenchymal neoplasms of the gastrointestinal tract, arising from the interstitial cells of Cajal. These tumors bridge the nervous system and muscular layers of the gastrointestinal tract, playing a crucial role in the digestive process. The incidence of GISTs demonstrates notable variations across different racial and ethnic groups, underscoring the need for in-depth analysis to understand the interplay of genetic, environmental, and socioeconomic factors behind these disparities. Linear regression analysis is a pivotal statistical tool in such epidemiological studies, offering insights into the temporal dynamics of disease incidence and the impact of public health interventions. Methodology This investigation employed a detailed dataset from 2009 to 2020, documenting GIST incidences across Asian, African American, Hispanic, and White populations. A meticulous preprocessing routine prepared the dataset for analysis, which involved data cleaning, normalization of racial terminologies, and aggregation by year and race. Linear regression models and Pearson correlation coefficients were applied to analyze trends and correlations in GIST incidences across the different racial groups, emphasizing an understanding of temporal patterns and racial disparities in disease incidence. Results The study analyzed GIST cases among four racial groups, revealing a male predominance (53.19%) and an even distribution of cases across racial categories: Whites (27.66%), Hispanics (25.53%), African Americans (24.47%), and Asians (22.34%). Hypertension was the most common comorbidity (32.98%), followed by heart failure (28.72%). The linear regression analysis for Asians showed a decreasing trend in GIST incidences with a slope of -0.576, an R-squared value of 0.717, and a non-significant p-value of 0.153. A significant increasing trend was observed for Whites, with a slope of 0.581, an R-squared value of 0.971, and a p-value of 0.002. African Americans exhibited a moderate positive slope of 0.277 with an R-squared value of 0.470 and a p-value of 0.201, indicating a non-significant increase. Hispanics showed negligible change over time with a slope of -0.095, an R-squared value of 0.009, and a p-value of 0.879, suggesting no significant trend. Conclusions This study examines GIST incidences across racial groups, revealing significant disparities. Whites show an increasing trend (p = 0.002), while Asians display a decreasing trend (p = 0.153), with stable rates in African Americans and Hispanics. Such disparities suggest a complex interplay of genetics, environment, and socioeconomic factors, highlighting the need for targeted research and interventions that address these differences and the systemic inequalities influencing GIST outcomes.
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A 26-year-old male with no significant medical history presented with hematochezia and was diagnosed with ulcerative colitis (UC) accompanied by immune thrombocytopenia (ITP) as an extraintestinal manifestation (EIM) of UC. This case report delves into the uncommon overlap between UC, a subtype of inflammatory bowel disease primarily affecting the colon and rectum, and ITP, an autoimmune condition leading to platelet destruction. The patient's atypical presentation and subsequent positive response to a treatment regimen targeting both UC and ITP underscores the necessity for a thorough and multifaceted diagnostic approach in individuals with UC, especially when faced with non-gastrointestinal symptoms like unexplained thrombocytopenia. The findings from this study enhance the understanding of UC's diverse manifestations and highlight its potential intersection with other autoimmune diseases, advocating for integrated care strategies in managing such intricate clinical cases.
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Background: Child maltreatment is associated with a higher probability of mental disorders and suicidal behavior in adolescence. Therefore, accurate psychometric instruments are essential to assess this. Objective: To validate the Spanish version of the Childhood Trauma Questionnaire-Short Form (CTQ-SF) in adolescents with suicide attempts. Methods: Multisite cohort study of 208 adolescents with suicide attempts using data from the following scales: Mini International Neuropsychiatric Interview (MINI), Columbia Suicide Severity Rating Scale (C-SSRS), Patient Health Questionnaire (PHQ-9), and CTQ-SF. Statistical analysis: CTQ-SF scores analyzed by descriptive statistics. Internal consistency: McDonald's omega and Cronbach's alpha. Concurrent validity with PHQ-9 and C-SSRS scores: Spearman correlation coefficient. Structural validity: Confirmatory factor analysis. Results: Floor and ceiling effects: Physical abuse and neglect as well as sexual abuse demonstrated high floor effects (50.0, 35.1, and 61.1% of adolescents, respectively). No ceiling effects were found. The CTQ-SF had excellent internal consistency (McDonald's omega = 0.94), as did the majority of its subscales (Cronbach's alpha 0.925-0.831) except for physical neglect (0.624). Its concurrent validity was modest, and the emotional neglect subscale had the lowest Spearman correlation coefficients (0.067-0.244). Confirmatory factor analysis: Compared with alternative factor structures, the original CTQ-SF model (correlated 5-factor) exhibited a better fit [S-B χ 2 = 676.653, p < 0; RMSEA (90% CI = 0.076-0.097) = 0.087; SRMR = 0.078; CFI = 0.980; TLI = 0.978]. Conclusion: The Spanish CTQ-SF is a reliable, valid instrument for assessing traumatic experiences in adolescents at high risk of suicide. It appears appropriate for use in routine clinical practice to monitor maltreatment in this group.
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Integrated treatments are often recommended for adolescents with substance use disorders (SUD) and comorbid pathologies. This study aims to compare the effectiveness of two different intervention programs (integrated and parallel) and to investigate treatment outcome predictors. Seventy-five adolescents (13-17 years old) with substance use and comorbid disorders referred to our outpatient program were randomized to integrated (n = 33) or parallel (n = 32) treatment groups. Their sociodemographic variables, psychopathology, substance use problems, and global functioning were assessed at baseline and 12 months after treatment initiation. Both treatments were associated with positive pre-post changes in several outcome variables (severity of school, family, and psychiatric problems; global functioning; and stage of change). Integrated treatment showed better outcome on adherence (χ2 = 14.328; p > .001) and a composite global measure based on the severity of drug-related problems (χ2 = 8.833, p = .003). Following an adaptive treatment strategy, we offered patients who dropped out of parallel treatment (n = 12) the possibility of entering integrated treatment. Eleven of them accepted and constituted a third comparison group (parallel-to-integrated). Multivariate logistic regression analysis showed that the likelihood of a positive global treatment outcome increased with integrated or parallel-to-integrated treatment, internalizing or mixed comorbid disorders, older age, and fewer legal issues. Integrated treatment showed better adherence and global treatment outcomes than parallel treatment in adolescent patients with dual disorders. Older age and fewer legal issues were also related to a positive global treatment outcome.
Los tratamientos integrados suelen recomendarse para adolescentes con trastornos por uso de sustancias (TUS) y patologías comórbidas. Este estudio compara la eficacia de dos programas de intervención (integrado y paralelo) e investiga factores predictores de resultados del tratamiento. Setenta y cinco adolescentes (13-17 años) con TUS y trastorno comórbido, remitidos a un programa ambulatorio, fueron asignados aleatoriamente a un tratamiento integrado (n = 33) o paralelo (n = 32). Se evaluaron variables sociodemográficas, psicopatología, consumo de sustancias y funcionamiento global al inicio del tratamiento y 12 meses después. Ambos tratamientos se asociaron con cambios positivos pre-post en diferentes variables (problemas escolares, familiares, psiquiátricos, funcionamiento global y estadio de cambio). El tratamiento integrado mostró mejores resultados en adherencia (χ2 = 14,328; p > ,001) y en una medida global compuesta basada en la gravedad de problemas relacionados con drogas (χ2 = 8,833; p = ,003). Siguiendo una estrategia de tratamiento adaptativa, ofrecimos a los pacientes que abandonaron el tratamiento paralelo (n = 12) la posibilidad de entrar en el integrado. Once aceptaron, constituyendo un tercer grupo de comparación («paralelo a integrado¼). El análisis de regresión logística multivariante mostró que la probabilidad de resultado global positivo aumentaba en los pacientes de los grupos integrado y «paralelo a integrado¼, con trastornos comórbidos internalizantes o mixtos, mayor edad y menores problemas legales. El tratamiento integrado mostró mejor adherencia y resultados globales que el paralelo en adolescentes con patología dual. Una mayor edad y menos problemas legales también se relacionaron con un resultado global positivo.
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Background: (1)Sarcopenia, or low skeletal mass index (SMI), contributes to higher lung cancer mortality. The SMI at third lumbar vertebrae (L3) is the reference standard for body composition analysis. However, there is a need to explore the validity of alternative landmarks in this population. We compared the agreement of sarcopenia identification at the first lumbar (L1) and second lumbar (L2) to L3 in non-Hispanic Black (NHB) and White (NHW) individuals with lung cancer. Methods: (2)This retrospective, cross-sectional study included 214 NHB and NHW adults with lung cancer. CT scans were analyzed to calculate the SMI at L1, L2, and L3. T-tests, chi-square, Pearson's correlation, Cohen's kappa, sensitivity, and specificity analysis were used. Results: (3)Subjects presented with a mean age of 68.4 ± 9.9 years and BMI of 26.3 ± 6.0 kg/m2. Sarcopenia prevalence varied from 19.6% at L1 to 39.7% at L3. Cohen's kappa coefficient was 0.46 for L1 and 0.64 for L2, indicating weak and moderate agreement for the identification of sarcopenia compared to L3. Conclusions: (4)Sarcopenia prevalence varied greatly depending on the vertebral landmark used for assessment. Using L2 or L1 alone resulted in a 16.8% and 23.8% misclassification of sarcopenia in this cohort of individuals with lung cancer.
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OBJECTIVES: To synthesise the dentoalveolar, periodontal and skeletal changes that occur when using maxillary expansion techniques assisted by temporary anchorage devices compared to conventional protocols. METHODS: Five databases and grey literature were consulted, up to December 2023, focusing on intervention designs and excluding other type of studies. The quality assessment was conducted by using the adaptation for orthodontics of the CONSORT statement, the guidelines for reporting non-randomised studies, the RoB-2 tool, and the ROBINS-I tool. A descriptive summary and meta-analysis using RevMan 5.4 were performed. RESULTS: Nine clinical trials were included (n=377 patients, mean age 13.2±0.6) with a diagnosis of transverse maxillary deficiency. The analysed studies showed qualitative dentoalveolar and periodontal changes after expansion, which were greater on the maxillary first premolars in tooth-borne appliances. Meta-analyses for some effects were included from two studies (n=64); patients who used tooth-borne appliances had greater effects of buccal intercoronal width between the premolars with statistically significant differences (Std Mean difference 2.34; 95% CI: 0.04-4.65 p=0.05). Conversely, those patients who used bone-borne or hybrid appliances had greater effects of buccal intercoronal width between molars with statistically significant differences (Std Mean difference -0.64; 95% CI: -1.38-0.10; p=0.09). CONCLUSIONS: According to the studies analysed, all measurements increased in the intervention groups after expansion. Quantitative analyses show different findings at dentoalveolar level when tooth-borne, bone-borne or hybrid appliances are considered. Nevertheless, the results should be taken with caution due to the heterogeneity of the studies. The protocol was registered at PROSPERO (CRD42021283170), with no funding to report.
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Maxilar , Métodos de Anclaje en Ortodoncia , Técnica de Expansión Palatina , Humanos , Técnica de Expansión Palatina/instrumentación , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Diente Premolar , AdolescenteRESUMEN
Streptococcus intermedius is an inhabitant of the oral cavity and gastrointestinal tract, known to cause deep-seated abscesses. Thereby, we present a previously healthy adolescent with esophageal perforation (EP) and secondary mediastinal and brain abscesses due to Streptococcus intermedius. EP is a potentially life-threatening condition that requires a prompt diagnosis.
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An inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal neoplasm of borderline malignant potential. Nearly half of all IMTs have rearrangement of anaplastic lymphoma kinase (ALK) locus on chromosome 2p23 which can be treated with targeted therapy. Herein, we describe an unusual presentation of IMT involving an anatomical region rarely implicated in this disease process. A 15-year-old male patient came to the ER with dysphagia and coffee ground emesis. On esophagogastroscopy, a nodular luminal obstructing 30 × 50 mm mass in the lower esophagus was found, which was continuous with a large, partially circumferential gastric mass extending from the mid-body to the proximal antrum. Biopsies from esophageal and gastric masses revealed submucosal lesions composed of cytologically bland spindle and epithelioid cells, intermingled with inflammatory infiltrate, for which several immunohistochemical (IHC) stains were performed. The molecular study demonstrated ATIC::ALK fusion. Based on morphological, IHC, and molecular study findings, the diagnosis of ALK-positive IMT was rendered. Because surgical excision was deemed infeasible, the patient was started on ALK-inhibiting therapy with crizotinib. The patient responded well with no evidence of residual or recurrent disease on follow-up imaging or surveillance esophagogastroduodenoscopy. Crizotinib was ultimately discontinued after 10 months of therapy, and the patient continues to undergo surveillance imaging for monitoring of disease burden.
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Retrotransposons are viral-like DNA sequences that constitute approximately 41% of the human genome. Studies in Drosophila, mice, cultured cells, and human brain indicate that retrotransposons are activated in settings of tauopathy, including Alzheimer's disease, and causally drive neurodegeneration. The anti-retroviral medication 3TC (lamivudine), a nucleoside analog reverse transcriptase inhibitor, limits retrotransposon activation and suppresses neurodegeneration in tau transgenic Drosophila, two mouse models of tauopathy, and in brain assembloids derived from patients with sporadic Alzheimer's disease. We performed a 24-week phase 2a open-label clinical trial of 300 mg daily oral 3TC (NCT04552795) in 12 participants aged 52-83 years with a diagnosis of mild cognitive impairment due to suspected Alzheimer's disease. Primary outcomes included feasibility, blood brain barrier penetration, effects of 3TC on reverse transcriptase activity in the periphery, and safety. Secondary outcomes included changes in cognition and fluid-based biomarkers of neurodegeneration and neuroinflammation. All participants completed the six-month trial; one event of gastrointestinal bleeding due to a peptic ulcer was reported. 3TC was detected in blood and cerebrospinal fluid (CSF) of all participants, suggestive of adherence to study drug and effective brain penetration. Cognitive measures remained stable throughout the study. Glial fibrillary acidic protein (GFAP) (P=0.03) and Flt1 (P=0.05) were significantly reduced in CSF over the treatment period; Aß42/40 (P=0.009) and IL-15 (P=0.006) were significantly elevated in plasma. While this is an open label study of small sample size, the significant decrease of some neurodegeneration- and neuroinflammation-related biomarkers in CSF, significantly elevated levels of plasma Aß42/40, and a trending decrease of CSF NfL after six months of 3TC exposure suggest a beneficial effect on subjects with mild cognitive impairment due to suspected Alzheimer's disease. Feasibility, safety, tolerability, and central nervous system (CNS) penetration assessments further support clinical evaluation of 3TC in a larger placebo-controlled, multi-dose clinical trial.
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To simulate a 200 nm photoexcitation in cyclobutanone to the n-3s Rydberg state, classical trajectories were excited from a Wigner distribution to the singlet state manifold based on excitation energies and oscillator strengths. Twelve singlet and 12 triplet states are treated using TD-B3LYP-D3/6-31+G** for the electronic structure, and the nuclei are propagated with the Tully surface hopping method. Using time-dependent density functional theory, we are able to predict the bond cleavage that takes place on the S1 surface as well as the ultrafast deactivation from the Rydberg n-3s state to the nπ*. After showing that triplet states and higher-lying singlet states do not play any crucial role during the early dynamics (i.e., the first 300 fs), the SA(6)-CASSCF(8,11)/aug-cc-pVDZ method is used as an electronic structure and the outcome of the non-adiabatic dynamic simulations is recomputed. Gas-phase ultrafast electron diffraction spectra are computed for both electronic structure methods, showing significantly different results.
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PURPOSE: To provide information about which pneumococcal vaccine could have greater coverage in Colombia. METHODS: This is a retrospective analysis of patients diagnosed with invasive pneumococcal disease (IPD) between 2015 and 2019 in Bogotá, Colombia. We compared the theoretical serotype coverage of the available anti-pneumococcal vaccines (i.e., PCV-10, PCV-10 SII, PCV-13, PCV-15, PCV-20, PCV-21, PCV24, PPSV-23) and the non-vaccine-covered serotypes stratified by age. RESULTS: 690 IPD cases were included. In children ≤5 y/o, of the approved vaccines PCV-20 showed the most theoretical protection (71.3 % [149/209]), while in adults aged 18-64 y/o was PCV-20 (61.8 % [164/265]), and in those ≥65 y/o was PPSV-23 (58.1 % [100/172]) followed by PCV-20 (55.2 % [95/172]). The non-covered serotypes represented one-third of the cohort (33.9 % [234/690]), being 6C (20.5 % [48/234]), 15A (12.8 % [30/234]), and 23A (11.5 % [27/234]) the most prevalent. CONCLUSION: Introducing PCV-20 for children and PCV-20 along with a PPSV-23 booster in adults may reduce IPD frequency in all ages in Colombia. The inclusion of non-covered serotypes is required for future vaccines.
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Infecciones Neumocócicas , Streptococcus pneumoniae , Adulto , Niño , Humanos , Lactante , Colombia/epidemiología , Estudios Retrospectivos , Vacunación , Vacunas Conjugadas/uso terapéutico , Vacunas Neumococicas/uso terapéutico , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/prevención & control , SerogrupoRESUMEN
Electrodes with nanostructured surface have emerged as promising low-impedance neural interfaces that can avoid the charge-injection restrictions typically associated to microelectrodes. In this work, we propose a novel approximation, based on a two-step template assisted electrodeposition technique, to obtain flexible nanostructured electrodes coated with core-shell Ni-Au vertical nanowires. These nanowires benefit from biocompatibility of the Au shell exposed to the environment and the mechanical properties of Ni that allow for nanowires longer and more homogeneous in length than their only-Au counterparts. The nanostructured electrodes show impedance values, measured by electrochemical impedance spectroscopy (EIS), at least 9 times lower than those of flat reference electrodes. This ratio is in good accordance with the increased effective surface area determined both from SEM images and cyclic voltammetry measurements, evidencing that only Au is exposed to the medium. The observed EIS profile evolution of Ni-Au electrodes over 7 days were very close to those of Au electrodes and differently from Ni ones. Finally, the morphology, viability and neuronal differentiation of rat embryonic cortical cells cultured on Ni-Au NW electrodes were found to be similar to those on control (glass) substrates and Au NW electrodes, accompanied by a lower glial cell differentiation. This positive in-vitro neural cell behavior encourages further investigation to explore the tissue responses that the implantation of these nanostructured electrodes might elicit in healthy (damaged) neural tissues in vivo, with special emphasis on eventual tissue encapsulation.
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Nanoestructuras , Nanocables , Ratas , Animales , Electrodos , Microelectrodos , Neuronas/fisiología , Impedancia EléctricaRESUMEN
On-the-fly non-adiabatic dynamics methods are becoming more important as tools to characterise the time evolution of a system after absorbing light. These methods, which calculate quantities such as state energies, gradients and interstate couplings at every time step, circumvent the requirement for pre-computed potential energy surfaces. There are a number of different algorithms used, the most common being Tully Surface Hopping (TSH), but all are approximate solutions to the time-dependent Schrödinger equation and benchmarking is required to understand their accuracy and performance. For this, a common set of systems and observables are required to compare them. In this work, we validate the on-the-fly direct dynamics variational multi-configuration Gaussian (DD-vMCG) method using three molecular systems recently suggested by Ibele and Curchod as molecular versions of the Tully model systems used to test one-dimensional non-adiabatic behaviour [Ibele et al., Phys. Chem. Chem. Phys. 2020, 22, 15183-15196]. Parametrised linear vibronic potential energy surfaces for each of the systems were also tested and compared to on-the-fly results. The molecules, which we term the Ibele-Curchod models, are ethene, DMABN and fulvene and the authors used them to test and compare several versions of the Ab Initio Multiple Spawning (AIMS) method alongside TSH. The three systems present different deactivation pathways after excitation to their ππ* bright states. When comparing DD-vMCG to AIMS and TSH, we obtain crucial differences in some cases, for which an explanation is provided by the classical nature and the chosen initial conditions of the TSH simulations.
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OBJECTIVE: This study aims to utilize the finite element method (FEM) to compare the dentoalveolar and mandibular effects associated with anterior mandibular repositioning using AdvanSync® (ADV) and Twin Block (TB). METHODS: A patient with Class II skeletal malocclusion and mandibular retrognathism was selected. A TB appliance was subsequently applied. Computed Tomography (CT) scans were acquired at the beginning of treatment (T1) and 8 months later (T2). Concurrently, a numerical TB model was validated through FEM simulations, which were compared with the T2 results. The ADV appliance was virtually simulated to evaluate stress and deformation on the condyle, symphysis, first lower molar and lower central incisors. RESULTS: Both simulations demonstrated significant mandibular advancement. However, ADV led to less incisor proclination and more molar intrusion compared to TB. ADV exhibited increased stress in the lower molar area, while TB had higher stress in the lower incisor region. Stress and deformations in the condyle and mandibular symphysis were similar in both simulations, with the highest stress observed at the condylar neck and the lowest at the upper pole of the condylar head. CONCLUSIONS: Both appliances achieved similar levels of mandibular advancement, with greater proclination of the lower central incisors and more widespread distribution of stress and molar intrusion when using ADV compared to TB.
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The structural, vibrational, and electronic properties of new inorganic X-phosphide nanotubes (ch-XPNT), with X = Al, Ga, or In and chirality of (5,5), are investigated. These new NTs display cap-hole ends, with the cap-hole features induced by the nonpassivated ends. Studies are based on density functional theory (DFT) using the M06-2X, PBE, and B3LYP functionals together with the LanL2DZ basis set. All nanostructures have been relaxed by minimizing the total energy, assuming a nonmagnetic nature and a total neutral charge. Note that the cap-hole NTs are terminated by a 10-atom ring, which in turn favors the geometrical ordering and yields stable structures. The (5,5) ch-XPNT are highly electrophilic and nonpolar, in addition to having high solvation energy values. Let us remark that solvation energies are produced by the intermolecular forces that involve the induced dipoles. Structural and vibrational results show that the X-P bonds are single bonds. Finally, results suggest that the inorganic nanotubes are structurally stable with semiconductor features, which means that their functionalization may yield interesting future applications.