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1.
J Neurosci ; 44(13)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38360748

RESUMEN

A prominent account of decision-making assumes that information is accumulated until a fixed response threshold is crossed. However, many decisions require weighting of information appropriately against time. Collapsing response thresholds are a mathematically optimal solution to this decision problem. However, our understanding of the neurocomputational mechanisms underlying dynamic response thresholds remains significantly incomplete. To investigate this issue, we used a multistage drift-diffusion model (DDM) and also analyzed EEG ß power lateralization (BPL). The latter served as a neural proxy for decision signals. We analyzed a large dataset (n = 863; 434 females and 429 males) from a speeded flanker task and data from an independent confirmation sample (n = 119; 70 females and 49 males). We showed that a DDM with collapsing decision thresholds, a process wherein the decision boundary reduces over time, captured participants' time-dependent decision policy more accurately than a model with fixed thresholds. Previous research suggests that BPL over motor cortices reflects features of a decision signal and that its peak, coinciding with the motor response, may serve as a neural proxy for the decision threshold. We show that BPL around the response decreased with increasing RTs. Together, our findings offer compelling evidence for the existence of collapsing decision thresholds in decision-making processes.


Asunto(s)
Toma de Decisiones , Masculino , Femenino , Humanos , Toma de Decisiones/fisiología , Tiempo de Reacción/fisiología
2.
Brain ; 147(1): 201-214, 2024 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-38058203

RESUMEN

Deficits in reward learning are core symptoms across many mental disorders. Recent work suggests that such learning impairments arise by a diminished ability to use reward history to guide behaviour, but the neuro-computational mechanisms through which these impairments emerge remain unclear. Moreover, limited work has taken a transdiagnostic approach to investigate whether the psychological and neural mechanisms that give rise to learning deficits are shared across forms of psychopathology. To provide insight into this issue, we explored probabilistic reward learning in patients diagnosed with major depressive disorder (n = 33) or schizophrenia (n = 24) and 33 matched healthy controls by combining computational modelling and single-trial EEG regression. In our task, participants had to integrate the reward history of a stimulus to decide whether it is worthwhile to gamble on it. Adaptive learning in this task is achieved through dynamic learning rates that are maximal on the first encounters with a given stimulus and decay with increasing stimulus repetitions. Hence, over the course of learning, choice preferences would ideally stabilize and be less susceptible to misleading information. We show evidence of reduced learning dynamics, whereby both patient groups demonstrated hypersensitive learning (i.e. less decaying learning rates), rendering their choices more susceptible to misleading feedback. Moreover, there was a schizophrenia-specific approach bias and a depression-specific heightened sensitivity to disconfirmational feedback (factual losses and counterfactual wins). The inflexible learning in both patient groups was accompanied by altered neural processing, including no tracking of expected values in either patient group. Taken together, our results thus provide evidence that reduced trial-by-trial learning dynamics reflect a convergent deficit across depression and schizophrenia. Moreover, we identified disorder distinct learning deficits.


Asunto(s)
Trastorno Depresivo Mayor , Esquizofrenia , Humanos , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico , Trastorno Depresivo Mayor/complicaciones , Depresión , Aprendizaje , Recompensa
3.
Sci Rep ; 13(1): 19180, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932359

RESUMEN

Performance monitoring (PM) is a vital component of adaptive behavior and known to be influenced by motivation. We examined effects of potential gain (PG) and loss avoidance (LA) on neural correlates of PM at different processing stages, using a task with trial-based changes in these motivational contexts. Findings suggest more attention is allocated to the PG context, with higher amplitudes for respective correlates of stimulus and feedback processing. The PG context favored rapid responses, while the LA context emphasized accurate responses. Lower response thresholds in the PG context after correct responses derived from a drift-diffusion model also indicate a more approach-oriented response style in the PG context. This cognitive shift is mirrored in neural correlates: negative feedback in the PG context elicited a higher feedback-related negativity (FRN) and higher theta power, whereas positive feedback in the LA context elicited higher P3a and P3b amplitudes, as well as higher theta power. There was no effect of motivational context on response-locked brain activity. Given the similar frequency of negative feedback in both contexts, the elevated FRN and theta power in PG trials cannot be attributed to variations in reward prediction error. The observed variations in the FRN indicate that the effect of outcome valence is modulated by motivational salience.


Asunto(s)
Electroencefalografía , Fenómenos Fisiológicos del Sistema Nervioso , Potenciales Evocados/fisiología , Motivación , Retroalimentación Psicológica/fisiología , Recompensa
4.
European J Pediatr Surg Rep ; 11(1): e15-e19, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37051184

RESUMEN

Both congenital diaphragmatic hernias (CDHs) and omphaloceles show relevant overall mortality rates as individual findings. The combination of the two has been described only sparsely in the literature and almost always with a fatal course. Here, we describe a term neonate with a rare high-risk constellation of left-sided CDH and a large omphalocele who was successfully treated on extracorporeal life support (ECLS). Prenatally, the patient was diagnosed with a large omphalocele and a left CDH with a lung volume of ∼27% and an observed to expected lung-to-head ratio of 30%. Due to respiratory insufficiency, an ECLS device was implanted. As weaning from ECLS was not foreseeable, the female infant underwent successful surgery on ECLS on the ninth day of life. Perioperative high-frequency oscillatory ventilation and circulatory and coagulation management under point-of-care monitoring were the main anesthesiological challenges. Over the following 3 days, ECLS weaning was successful, and the patient was extubated after another 43 days. Surgical treatment on ECLS can expand the spectrum of therapy in high-risk constellations if potential risks are minimized and there is close interdisciplinary cooperation.

5.
Children (Basel) ; 10(3)2023 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-36980100

RESUMEN

Resection of lung metastases in children with solid tumors is regularly hampered by limited intraoperative detectability and relevant operative trauma of the open surgical access. The aim of this study was to analyze thoracoscopic resection of lung metastases in children following CT-guided labeling with coil wires. We retrospectively analyzed data of children and adolescents undergoing this approach at our institution between 2010 and 2022 with regard to technical aspects as well as surgical and oncological data. Within this period, we performed this procedure on 12 patients wherein we resected 18 lesions (1-5 per patient). The median age of patients was 178 months (51-265). The median duration of coil wire placement was 41 min (30-173) and the median surgery time was 53 min (11-157). No conversions were necessary and no intraoperative complications occurred. Complete microscopic resection (R0) was achieved in all labeled lesions and malignant tumor components were found in 5/12 patients. Our study shows that with a careful patient selection, thoracoscopic resection of lung metastases after coil wire labeling is a safe and reproducible procedure in children. Using this approach, lesions that are expected to have a reduced intraoperative detectability during open surgery become resectable. Patients benefit from the minimally invasive surgical access and reduced operative trauma.

6.
ACS Nano ; 16(10): 17435-17443, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36239301

RESUMEN

Polycyclic aromatic compounds with fused benzene rings offer an extraordinary versatility as next-generation organic semiconducting materials for nanoelectronics and optoelectronics due to their tunable characteristics, including charge-carrier mobility and optical absorption. Nonplanarity can be an additional parameter to customize their electronic and optical properties without changing the aromatic core. In this work, we report a combined experimental and theoretical study in which we directly observe large, geometry-induced modifications in the frontier orbitals of a prototypical dye molecule when adsorbed on an atomically thin dielectric interlayer on a metallic substrate. Experimentally, we employ angle-resolved photoemission experiments, interpreted in the framework of the photoemission orbital tomography technique. We demonstrate its sensitivity to detect geometrical bends in adsorbed molecules and highlight the role of the photon energy used in experiment for detecting such geometrical distortions. Theoretically, we conduct density functional calculations to determine the geometric and electronic structure of the adsorbed molecule and simulate the photoemission angular distribution patterns. While we found an overall good agreement between experimental and theoretical data, our results also unveil limitations in current van der Waals corrected density functional approaches for such organic/dielectric interfaces. Hence, photoemission orbital tomography provides a vital experimental benchmark for such systems. By comparison with the state of the same molecule on a metallic substrate, we also offer an explanation why the adsorption on the dielectric induces such large bends in the molecule.

7.
Neuroimage ; 259: 119437, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35788041

RESUMEN

Optimal decision making in complex environments requires dynamic learning from unexpected events. To speed up learning, we should heavily weight information that indicates state-action-outcome contingency changes and ignore uninformative fluctuations in the environment. Often, however, unrelated information is hard to ignore and can potentially bias our learning. Here we used computational modelling and EEG to investigate learning behaviour in a modified probabilistic choice task that introduced two task-irrelevant factors that were uninformative for optimal task performance, but nevertheless could potentially bias learning: pay-out magnitudes were varied randomly and, occasionally, feedback presentation was enhanced by visual surprise. We found that participants' overall good learning performance was biased by distinct effects of these non-normative factors. On the neural level, these parameters are represented in a dynamic and spatiotemporally dissociable sequence of EEG activity. Later in feedback processing the different streams converged on a central to centroparietal positivity reflecting a signal that is interpreted by downstream learning processes that adjust future behaviour.


Asunto(s)
Toma de Decisiones , Electroencefalografía , Sesgo , Retroalimentación , Humanos , Recompensa
8.
Sci Adv ; 8(29): eabn0819, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35867796

RESUMEN

Tracing the modifications of molecules in surface chemical reactions benefits from the possibility to image their orbitals. While delocalized frontier orbitals with π character are imaged routinely with photoemission orbital tomography, they are not always sensitive to local chemical modifications, particularly the making and breaking of bonds at the molecular periphery. For such bonds, σ orbitals would be far more revealing. Here, we show that these orbitals can indeed be imaged in a remarkably broad energy range and that the plane wave approximation, an important ingredient of photoemission orbital tomography, is also well fulfilled for these orbitals. This makes photoemission orbital tomography a unique tool for the detailed analysis of surface chemical reactions. We demonstrate this by identifying the reaction product of a dehalogenation and cyclodehydrogenation reaction.

9.
Eur J Trauma Emerg Surg ; 48(5): 3393-3399, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35639113

RESUMEN

PURPOSE: Nonsurgical management has been identified as the treatment of choice for femoral shaft fractures in children below four years of age. For various reasons, the surgical approach has become increasingly popular in recent years. The aim of this study is to report results after vertical skin traction and analyze the benefits of this technique as well as to point out advantages compared with surgery in this age group. METHODS: The authors performed a retrospective data analysis, including all patients with femoral shaft fractures below the age of four who were treated with vertical skin traction at our institution between January 2006 and December 2016. RESULTS: Skin traction for a femoral shaft fracture was performed for 36 patients (mean age 1.6 years; 1 day-3.5 years). The mean duration of traction was 18.5 days (14-30). Complications included soft tissue affections (n = 5), which all healed spontaneously. Consolidation was observed in all fractures. Initial axial deviations and shortening did not change during traction until consolidation (p > 0.05), and no relevant torsion deformity occurred (p = 0.01). Patients gained full weight-bearing within 12.3 days (7-40) following end of traction. At the final follow-up, after a mean of 29.3 months (12-192), leg-length discrepancy (mean 7.1 mm; 5-20) was found on radiograms in nine cases, and axial deviations (mean 7.7°; 5-25) were documented in seven cases. None of the patients had limitations in daily activities or sports. CONCLUSION: Skin traction is a technically easy, safe, and non-invasive treatment modality for femoral shaft fractures in children below the age of four years. Strong results are obtained benefited from a high potential of growth-related correction, and in principle no anesthesia is needed. A prolonged hospitalization and socio-economic factors maintain the ongoing debate in comparison with the surgical approach. LEVEL OF EVIDENCE: Level III, retrospective.


Asunto(s)
Fracturas del Fémur , Tracción , Niño , Preescolar , Diáfisis , Fracturas del Fémur/cirugía , Fémur/cirugía , Humanos , Lactante , Estudios Retrospectivos , Tracción/métodos , Resultado del Tratamiento
10.
Neuroimage ; 257: 119322, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35577025

RESUMEN

The feedback-related negativity (FRN) is a well-established electrophysiological correlate of feedback-processing. However, there is still an ongoing debate whether the FRN is driven by negative or positive reward prediction errors (RPE), valence of feedback, or mere surprise. Our study disentangles independent contributions of valence, surprise, and RPE on the feedback-related neuronal signal including the FRN and P3 components using the statistical power of a sample of N = 992 healthy individuals. The participants performed a modified time-estimation task, while EEG from 64 scalp electrodes was recorded. Our results show that valence coding is present during the FRN with larger amplitudes for negative feedback. The FRN is further modulated by surprise in a valence-dependent way being more positive-going for surprising positive outcomes. The P3 was strongly driven by both global and local surprise, with larger amplitudes for unexpected feedback and local deviants. Behavioral adaptations after feedback and FRN just show small associations. Results support the theory of the FRN as a representation of a signed RPE. Additionally, our data indicates that surprising positive feedback enhances the EEG response in the time window of the P3. These results corroborate previous findings linking the P3 to the evaluation of PEs in decision making and learning tasks.


Asunto(s)
Potenciales Evocados , Retroalimentación Psicológica , Electroencefalografía/métodos , Potenciales Evocados/fisiología , Retroalimentación , Retroalimentación Psicológica/fisiología , Humanos , Recompensa
11.
J Phys Chem C Nanomater Interfaces ; 126(10): 5036-5045, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35330758

RESUMEN

Hexacene, composed of six linearly fused benzene rings, is an organic semiconductor material with superior electronic properties. The fundamental understanding of the electronic and chemical properties is prerequisite to any possible application in devices. We investigate the orientation and interface properties of highly ordered hexacene monolayers on Ag(110) and Cu(110) with X-ray photoemission spectroscopy (XPS), photoemission orbital tomography (POT), X-ray absorption spectroscopy (XAS), low-energy electron diffraction (LEED), scanning tunneling microscopy (STM), and density functional theory (DFT). We find pronounced differences in the structural arrangement of the molecules and the electronic properties at the metal/organic interfaces for the two substrates. While on Cu(110) the molecules adsorb with their long molecular axis parallel to the high symmetry substrate direction, on Ag(110), hexacene adsorbs in an azimuthally slightly rotated geometry with respect to the metal rows of the substrate. In both cases, molecular planes are oriented parallel to the substrate. A pronounced charge transfer from both substrates to different molecular states affects the effective charge of different C atoms of the molecule. Through analysis of experimental and theoretical data, we found out that on Ag(110) the LUMO of the molecule is occupied through charge transfer from the metal, whereas on Cu(110) even the LUMO+1 receives a charge. Interface dipoles are determined to a large extent by the push-back effect, which are also found to differ significantly between 6A/Ag(110) and 6A/Cu(110).

12.
Neonatology ; 119(2): 238-245, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35235935

RESUMEN

BACKGROUND: Gastric transposition (GT) is a possible option for esophageal replacement in long-gap esophageal atresia (LGEA). The present study aims to report and compare indications and outcome of laparoscopic-assisted GT (LAGT) versus open (OGT) GT for LGEA repair. METHODS: Retrospective single-center analysis of all LGEA patients undergoing GT between 2002 and 2021. RESULTS: Thirty-one children with LGEA underwent GT. Of these, 19 underwent LAGT (mean weight at surgery 5.6 kg; mean age 167 days) and 12 underwent OGT (6.1 kg; 233 days). Indications for OGT were previous surgery (n = 7), associated severe cardiac malformations (n = 4), and a simultaneous resection of a choledochal cyst (n = 1). The conversion rate was 1. The two procedures (LAGT/OGT) differed in anesthetic time (308/350 min), duration of ventilation (5.1/5.3 days), hospital stay (34/32 days), and complications (22/15). None of the differences reached statistical significance. Outcome was also comparable: completely oral nutrition uptake in 66%/73%, slow weight gain in the low centiles in both groups, no patient developed dumping syndrome, symptomatic reflux was seen in 1 patient after OGT. CONCLUSION: In our cohort, LAGT for repair of LGEA provided similar outcomes as open surgery. The minimally invasive approach preserves thoracal structures, prevents additional thoracotomy or laparotomy, and is faster. To realize LAGT, a postpartal treatment concept including gastrostomy placement via a microincision to minimize adhesions is essential. The open surgical approach should be considered in cases of previous extensive surgical attempts of EA correction causing severe adhesions as well as associated anomalies or genetic syndromes causing hemodynamic instability.


Asunto(s)
Atresia Esofágica , Laparoscopía , Niño , Atresia Esofágica/cirugía , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Estudios Retrospectivos , Estómago , Resultado del Tratamiento
13.
Arch Orthop Trauma Surg ; 142(8): 1903-1910, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33974141

RESUMEN

INTRODUCTION: Pediatric radial neck and head fractures are rare, accounting for only 1% of all fractures in children. The aim of this study is to describe the management and results of the respective fracture types and different injury characteristics. MATERIALS AND METHODS: This study performs a retrospective data analysis of 100 consecutive patients with a fracture of the proximal radius treated in a single high-volume pediatric trauma center. RESULTS: One hundred patients [mean age 7.5 years (1-15)] were documented with a fracture of the proximal radius between 3/2011 and 12/2019. The gender distribution was 62 girls and 38 boys. Twenty-seven patients had concomitant injuries. Conservative treatment was performed in 63 patients (Judet I = 27; II = 30; III = 6; Mason I = 2) using an above-the-elbow cast for 21 days (6-35). Surgical treatment was performed in 37 patients (Judet II = 3; III = 22; IV = 5; V = 7) using elastic stable intramedullary nailing (ESIN). Open reduction was necessary in five cases, and additional immobilization was performed in 32 cases. Six complications occurred: loss of implant stability (n = 2), healing in malalignment, pseudarthrosis, radioulnar synostosis, and a persisting hypoesthesia at the thumb. As a result, two ESIN osteosynthesis were revised, and one radial head resection was performed. Loss of movement was seen in 11% of cases, overall Mayo elbow performance index (MEPI) was 99.8 (90-100), and none of the patients experienced negative impacts on activities of daily life. CONCLUSIONS: Proximal radial fractures occur predominately without dislocation. Good results are obtained with conservative treatment throughout. In cases with displacement exceeding growth-related correction, ESIN is the undisputed treatment of choice. Open surgery and long immobilization periods should be avoided whenever possible.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas del Radio , Clavos Ortopédicos , Niño , Codo , Femenino , Fijación Intramedular de Fracturas/efectos adversos , Humanos , Masculino , Radio (Anatomía)/cirugía , Fracturas del Radio/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
14.
Eur J Trauma Emerg Surg ; 48(5): 3471-3478, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34338820

RESUMEN

PURPOSE: ESIN (elastic stable intramedullary nailing) is considered the gold standard for various pediatric fractures. The aim of this study was to analyze the incidence and type of complications during or after TEN (titanium elastic nail) removal. METHODS: A retrospective data analysis was performed. Metal removal associated complications and preoperative extraosseous length/outlet angle of TENs as possible causes of complications were assessed. RESULTS: The complication rate in 384 TEN removals was 3.1% (n = 12). One major complication (rupture of M. extensor pollicis brevis) was documented. One refracture at the forearm occurred, however, remodeling prior TEN removal was completed. Ten minor complications were temporary or without irreversible restrictions (3 infections, 5 scaring/granuloma, 2 temporary paraesthesia). In 38 cases (16 forearms, 10 femora, 9 humeri, 3 lower legs), intra-operative fluoroscopy had to be used to locate the implants. In patients with forearm fractures, extraosseous implant length was relatively shorter than in cases without fluoroscopy (p = 0.01), but outlet angle of TENs was not significantly different in these two groups (28.5° vs 25.6°). In patients with femur fractures, extraosseous implant length and outlet angle were tendentially shorter, respectively, lower, but this did not reach statistical significance. CONCLUSION: Removal of TENs after ESIN is a safe procedure with a low complication rate. Technically inaccurate TEN implantation makes removal more difficult and complicated. To prevent an untimely removal and patient discomfort, nail ends must be exactly positioned and cut. Intraoperative complications may be minimized with removal of TENs before signs of overgrowth. EVIDENCE: Level III, retrospective.


Asunto(s)
Fracturas del Fémur , Fijación Intramedular de Fracturas , Clavos Ortopédicos/efectos adversos , Niño , Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Fijación Intramedular de Fracturas/métodos , Curación de Fractura , Humanos , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Titanio , Resultado del Tratamiento
15.
Injury ; 52(8): 2257-2264, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34148654

RESUMEN

Purpose The optimal management of medial humeral epicondyle fractures continues to be debated since decades. This single center study analyzes changes and optimizations of treatment over an observation period of 16 years and reports the results. Materials and Methods Retrospective analysis of all patients treated with a medial humeral epicondyle fracture between 2005 and 2020 at our institution. Results Ninety-six patients (mean 9.3 years, range 1 - 15) were included in the study. In 25 cases (26 %), the fracture was associated with an elbow dislocation. Most patients received surgical treatment (83.3 %), whereas 17.7 % were treated nonoperatively. Surgical treatment consisted of open reduction and fixation with compression screw (n = 44 steel, n = 2 absorbable), K-wire (n = 30), a combination of screw/K-wire (n = 2), or a PDS suture (n = 1). Compression screws have been used significantly more often in the latter half of the study period (p = 0.006). Patients were immobilized in a long arm cast for 29 days (range 11 - 50). Eleven surgically treated patients were early mobilized in an elbow orthosis. After a mean follow up of 7.6 months [2 - 61), Mayo elbow performance index (MEPI) outcome was excellent in all 96 patients. Loss of elbow movement (LOM) was found to be mild in 30 and moderate in 15 patients. LOM was found to be associated with surgical treatment (p = 0.001), and with concomitant elbow dislocations (p = 0.29). One pseudarthrosis occurred after conservative treatment. A persistence of ulnar nerve palsy or recurrent joint instability has not been described. Conclusion Most children with medial humeral epicondyle fractures nowadays undergo surgery. Screw osteosynthesis represents the increasingly preferred method in order to prevent joint instability or non-union, and to allow shorter immobilization duration. Overall results after medial epicondyle fractures are good.


Asunto(s)
Articulación del Codo , Fracturas del Húmero , Luxaciones Articulares , Niño , Codo , Articulación del Codo/diagnóstico por imagen , Articulación del Codo/cirugía , Fijación Interna de Fracturas , Humanos , Fracturas del Húmero/diagnóstico por imagen , Fracturas del Húmero/cirugía , Húmero , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del Tratamiento
16.
J Phys Chem C Nanomater Interfaces ; 125(5): 2918-2925, 2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33603943

RESUMEN

Longer acenes such as heptacene are promising candidates for optoelectronic applications but are unstable in their bulk structure as they tend to dimerize. This makes the growth of well-defined monolayers and films problematic. In this article, we report the successful preparation of a highly oriented monolayer of heptacene on Ag(110) by thermal cycloreversion of diheptacenes. In a combined effort of angle-resolved photoemission spectroscopy and density functional theory (DFT) calculations, we characterize the electronic and structural properties of the molecule on the surface in detail. Our investigations allow us to unambiguously confirm the successful fabrication of a highly oriented complete monolayer of heptacene and to describe its electronic structure. By comparing experimental momentum maps of photoemission from frontier orbitals of heptacene and pentacene, we shed light on differences between these two acenes regarding their molecular orientation and energy-level alignment on the metal surfaces.

17.
Cogn Affect Behav Neurosci ; 21(3): 573-591, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33025512

RESUMEN

Monitoring for errors and behavioral adjustments after errors are essential for daily life. A question that has not been addressed systematically yet, is whether consciously perceived errors lead to different behavioral adjustments compared to unperceived errors. Our goal was to develop a task that would enable us to study different commonly observed neural correlates of error processing and post-error adjustments in their relation to error awareness and accuracy confidence in a single experiment. We assessed performance in a new number judgement error awareness task in 70 participants. We used multiple, robust, single-trial EEG regressions to investigate the link between neural correlates of error processing (e.g., error-related negativity (ERN) and error positivity (Pe)) and error awareness. We found that only aware errors had a slowing effect on reaction times in consecutive trials, but this slowing was not accompanied by post-error increases in accuracy. On a neural level, error awareness and confidence had a modulating effect on both the ERN and Pe, whereby the Pe was most predictive of participants' error awareness. Additionally, we found partial support for a mediating role of error awareness on the coupling between the ERN and behavioral adjustments in the following trial. Our results corroborate previous findings that show both an ERN/Pe and a post-error behavioral adaptation modulation by error awareness. This suggests that conscious error perception can support meta-control processes balancing the recruitment of proactive and reactive control. Furthermore, this study strengthens the role of the Pe as a robust neural index of error awareness.


Asunto(s)
Electroencefalografía , Potenciales Evocados , Concienciación , Humanos , Procesos Mentales , Desempeño Psicomotor , Tiempo de Reacción
18.
ACS Nano ; 14(11): 15766-15775, 2020 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-33186031

RESUMEN

We revisit the question of kekulene's aromaticity by focusing on the electronic structure of its frontier orbitals as determined by angle-resolved photoemission spectroscopy. To this end, we have developed a specially designed precursor, 1,4,7(2,7)-triphenanthrenacyclononaphane-2,5,8-triene, which allows us to prepare sufficient quantities of kekulene of high purity directly on a Cu(111) surface, as confirmed by scanning tunneling microscopy. Supported by density functional calculations, we determine the orbital structure of kekulene's highest occupied molecular orbital by photoemission tomography. In agreement with a recent aromaticity assessment of kekulene based solely on C-C bond lengths, we conclude that the π-conjugation of kekulene is better described by the Clar model rather than a superaromatic model. Thus, by exploiting the capabilities of photoemission tomography, we shed light on the question which consequences aromaticity holds for the frontier electronic structure of a π-conjugated molecule.

19.
J Pediatr Surg ; 55(11): 2335-2341, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32646666

RESUMEN

BACKGROUND/PURPOSE: Among the options for esophageal replacement in long-gap esophageal atresia (LGEA), gastric transposition (GT) is accessible for an endoscopic approach. Here we report a novel technique and functional results after laparoscopic-assisted gastric transposition (LAGT), including pyloric dilatation in patients with LGEA. METHODS: Retrospective analysis of 14 children undergoing LAGT. Surgical steps included the release of the gastrostomy, transumbilical ante-situ section of the stomach including pyloric balloon-dilation, and laparoscopically controlled transhiatal retromediastinal blunt dissection followed by LAGT for cervical anastomosis to the proximal esophagus. RESULTS: The median age at LAGT was 110 days (33-327 days), bodyweight 5.3 kg (3.1-8.3 kg). Operation time was 255 min (180-436 min); one conversion was necessary. The duration of ventilation was 4 days (1-14 days). Postpyloric feeding was started after 2 days, and oral feeding after 13 days. Complications were recurrent pleural effusion or pneumothorax and transient Horner syndrome or transient incomplete paresis of the recurrence nerve. After a median follow-up of 60 months (13-240 months), all children have a patent upper GI tract, show weight gain, and are fed without delayed gastric emptying, dumping, or reflux. Severe (n = 1) or mild (n = 2) anastomotic or pyloric (n = 5) stenosis was resolved with endoscopic dilatations. CONCLUSIONS: Functional outcome after LAGT in patients with LGEA is good. The laparoscopic retromediastinal dissection preserves thoracal structures and increases patients' safety. The technique of pyloric dilatation might also prevent dumping syndrome. TYPE OF STUDY: Case Series with no Comparison Group. LEVEL OF EVIDENCE: Level IV.


Asunto(s)
Dilatación , Atresia Esofágica , Laparoscopía , Anastomosis Quirúrgica , Atresia Esofágica/cirugía , Humanos , Lactante , Estudios Retrospectivos , Resultado del Tratamiento
20.
Clin Psychol Sci ; 7(3): 545-565, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-32655984

RESUMEN

Self-compassion and its cultivation in psychological interventions are associated with improved mental health and well-being. However, the underlying processes for this are not well understood. We randomly assigned 135 participants to study the effect of two short-term self-compassion exercises on self-reported-state mood and psychophysiological responses compared to three control conditions of negative (rumination), neutral, and positive (excitement) valence. Increased self-reported-state self-compassion, affiliative affect, and decreased self-criticism were found after both self-compassion exercises and the positive-excitement condition. However, a psychophysiological response pattern of reduced arousal (reduced heart rate and skin conductance) and increased parasympathetic activation (increased heart rate variability) were unique to the self-compassion conditions. This pattern is associated with effective emotion regulation in times of adversity. As predicted, rumination triggered the opposite pattern across self-report and physiological responses. Furthermore, we found partial evidence that physiological arousal reduction and parasympathetic activation precede the experience of feeling safe and connected.

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