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SIGNIFICANCE: Analyzing narratives in patients' medical records using a framework that combines natural language processing (NLP) and machine learning may help uncover the underlying patterns of patients' visual capabilities and challenges that they are facing and could be useful in analyzing big data in optometric research. PURPOSE: The primary goal of this study was to demonstrate the feasibility of applying a framework that combines NLP and machine learning to analyze narratives in patients' medical records. To test and validate our framework, we applied it to analyze records of low vision patients and to address two questions: Was there association between patients' narratives related to activities of daily living and the quality of their vision? Was there association between patients' narratives related to activities of daily living and their sentiments toward certain "assistive items"? METHODS: Our dataset consisted of 616 records of low vision patients. From patients' complaint history, we selected multiple keywords that were related to common activities of daily living. Sentences related to each keyword were converted to numerical data using NLP techniques. Machine learning was then applied to classify the narratives related to each keyword into two categories, labeled based on different "factors of interest" (acuity, contrast sensitivity, and sentiments of patients toward certain "assistive items"). RESULTS: Using our proposed framework, when patients' narratives related to specific keywords were used as input, our model effectively predicted the categories of different factors of interest with promising performance. For example, we found strong associations between patients' narratives and their acuity or contrast sensitivity for certain activities of daily living (e.g., "drive" in association with acuity and contrast sensitivity). CONCLUSIONS: Despite our limited dataset, our results show that the proposed framework was able to extract the semantic patterns stored in medical narratives and to predict patients' sentiments and quality of vision.
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Actividades Cotidianas , Aprendizaje Automático , Narración , Procesamiento de Lenguaje Natural , Humanos , Femenino , Masculino , Baja Visión/fisiopatología , Baja Visión/psicología , Baja Visión/rehabilitación , Agudeza Visual/fisiología , Anciano , Persona de Mediana EdadRESUMEN
Previous studies showed that elongation and symmetry (two ubiquitous aspects of natural stimuli) are important attributes in object perception and recognition, which in turn suggests that these geometrical factors may contribute to the selection of perceptual reference-frames. However, whether and how these attributes guide the selection of reference-frames is still poorly understood. The goal of this study was to examine systematically the roles of elongation and symmetry, as well as their combination, in the selection of reference axis and how these axes are developed for unfamiliar objects. We designed our experiments to eliminate two potential confounding factors: (i) extraneous environmental cues, such as edges of the screen, etc. (by using VR) and (ii) pre-learned cues for familiar objects and shapes (by using reinforcement learning of novel shapes). We used algorithmically generated textures with different orientations having specified levels of symmetry and elongation as the stimuli. In each trial, we presented only one stimulus and asked observers to report if the stimulus was in its original form or a flipped (mirror-image) one. Feedback was provided at the end of each trial. Based on previous studies on mental rotation, we hypothesized that the selection of a reference-frame defined by symmetry and/or elongation would be revealed by a linear relationship between reaction-times and the angular-deviation from either the most symmetrical or the most elongated orientation. Our results are consistent with this hypothesis. We found that subjects performed mental rotation to transform images to their reference axes and used the most symmetrical or elongated orientation as the reference axis when only one factor was presented, and they used a "winner-take-all" strategy when both factors were presented, with elongation being more dominant than symmetry. We discuss theoretical implications of these findings, in particular in the context of "canonical sensorimotor theory."
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High-performance catalysts sufficient to significantly reduce the energy barrier of water activation are crucial in facilitating reactions that are restricted by water dissociation. Herein we present a Cu-Co double-atom catalyst (CuCo-DAC), which possesses a uniform and well-defined CuCoN6 (OH) structure, and works together to promote water activation in silane oxidation. The catalyst achieves superior catalytic performance far exceeding that of single-atom catalysts (SACs). Various functional silanes are converted into silanols with up to 98 % yield and 99 % selectivity. Kinetic studies show that the activation energy of silane oxidation by CuCo-DAC is significantly lower than that of Cu single-atom catalyst (Cu-SAC) and Co single-atom catalyst (Co-SAC). Theoretical calculations demonstrate two different reaction pathways where water splitting is the rate-determining step and it is accelerated by CuCo-DAC, whereas H2 formation is key for its single-atom counterpart.
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Surface molecular imprinting (MI) is one of the most efficient techniques to improve selectivity in a catalytic reaction. Heretofore, a prerequisite to fabricating selective catalysts by MI strategies is to sacrifice the number of surface-active sites, leading to a remarkable decrease of activity. Thus, it is highly desirable to design molecular imprinting catalysts (MICs) in which both the catalytic activity and selectivity are significantly enhanced. Herein, a series of MICs are prepared by sequentially adsorbing imprinting molecules (nitro compounds, N) and imprinting ligand (1,10-phenanthroline, L) over the copper surface of Cu/Al2O3. The resulting Cu/Al2O3-N-L MICs not only offer promoted catalytic selectivity but also enhance catalytic activity for nitro compounds hydrogenation by an creating imprinting cavity derived from the presorption of N and forming new active Cu-N sites at the interface of the copper sites and L. Characterizations by means of various experimental investigations and DFT calculations disclose that the molecular imprinting effect (promoted activity and selectivity) originates from the formation of new active Cu-N sites and precise imprinting cavities, endowing promoted catalytic selectivity and activity on the hydrogenation of nitro compounds.
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Our brain employs mechanisms to adapt to changing visual conditions. In addition to natural changes in our physiology and those in the environment, our brain is also capable of adapting to "unnatural" changes, such as inverted visual-inputs generated by inverting prisms. In this study, we examined the brain's capability to adapt to hyperspaces. We generated four spatial-dimensional stimuli in virtual reality and tested the ability to distinguish between rigid and non-rigid motion. We found that observers are able to differentiate rigid and non-rigid motion of hypercubes (4D) with a performance comparable to that obtained using cubes (3D). Moreover, observers' performance improved when they were provided with more immersive 3D experience but remained robust against increasing shape variations. At this juncture, we characterize our findings as "3 1/2 D perception" since, while we show the ability to extract and use 4D information, we do not have yet evidence of a complete phenomenal 4D experience.
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Heterogeneously catalyzed N-formylation of amines to formamide with CO2 /H2 is highly attractive for the valorization of CO2 . However, the relationship of the catalytic performance with the catalyst structure is still elusive. Herein, mixed valence catalysts containing Cu2 O/Cu interface sites were constructed for this transformation. Both aliphatic primary and secondary amines with diverse structures were efficiently converted into the desired formamides with good to excellent yields. Combined ex and in situ catalyst characterization revealed that the presence of Cu2 O/Cu interface sites was vital for the excellent catalytic activity. Density functional theory (DFT) calculations demonstrated that better catalytic activity of Cu2 O/Cu(111) than Cu(111) is attributed to the assistance of oxygen at the Cu2 O/Cu interface (Ointer ) in formation of Ointer -H moieties, which not only reduce the apparent barrier of HCOOH formation but also benefit the desorption of the desired N-formylated amine, leading to high activity and selectivity.
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The perception of motion not only depends on the detection of motion signals but also on choosing and applying reference-frames according to which motion is interpreted. Here we propose a neural model that implements the common-fate principle for reference-frame selection. The model starts with a retinotopic layer of directionally-tuned motion detectors. The Gestalt common-fate principle is applied to the activities of these detectors to implement in two neural populations the direction and the magnitude (speed) of the reference-frame. The output activities of retinotopic motion-detectors are decomposed using the direction of the reference-frame. The direction and magnitude of the reference-frame are then applied to these decomposed motion-vectors to generate activities that reflect relative-motion perception, i.e., the perception of motion with respect to the prevailing reference-frame. We simulated this model for classical relative motion stimuli, viz., the three-dot, rotating-wheel, and point-walker (biological motion) paradigms and found the model performance to be close to theoretical vector decomposition values. In the three-dot paradigm, the model made the prediction of perceived curved-trajectories for the target dot when its horizontal velocity was slower or faster than the flanking dots. We tested this prediction in two psychophysical experiments and found a good qualitative and quantitative agreement between the model and the data. Our results show that a simple neural network using solely motion information can account for the perception of group and relative motion.
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Percepción de Movimiento , Humanos , Movimiento (Física) , Redes Neurales de la ComputaciónRESUMEN
The plasma scalpel is an application of gas discharges in electrosurgery. This paper introduces the device structure and physicochemical parameters of the two types of plasma scalpels, namely, a single-electrode Ar discharge device (argon plasma coagulation) and a two-electrode discharge device in normal saline. The diagnostic methods, including the voltage and current characteristics, optical emission spectroscopy, electron spin resonance, and high-speed imaging, are introduced to determine the critical process parameters, such as the plasma power, the gas temperature, the electron density, and the density of active species, and study the ignition dynamics of the plasma discharges in water. The efficacy of the plasma scalpel is mainly based on the physical effects of the electric current and electric field, in addition to the chemical effects of high-density energetic electrons and reactive species. These two effects can be adjusted separately to increase the treatment efficacy of the plasma scalpel. Specific guidance on further improvements of the plasma scalpel devices is also provided.
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BACKGROUND: Cervical cancer is a common gynecological cancer among women worldwide. OBJECTIVE: To determine the effects of 6 MV and 10 MV volumetric-modulated arc therapy (VMAT) photon beams on the target volume (TV) planning and critical organs in cases of cervical cancer. METHODS: Fifty patients with carcinoma of the cervix who underwent radiotherapy were selected. The transverse diameter (T) of the cross section of the upper edge of the sacroiliac joint on computerized tomography (CT) images of the patients was measured, and the mean value was calculated as 34 cm. All patients were divided into two groups: Group A (T < 34 cm) and Group B (T > 34 cm). The VMAT plans were generated using 6 MV and 10 MV plans separately. The prescription dose was 47.5 Gy, and the daily dose was 1.9 Gy. RESULTS: In Group A, the planning target volume (PTV) dose assessment parameters of 6 MV and 10 MV plans and their homogeneity and conformity indices were not statistically significantly different. A significant difference was observed between the 6 MV and 10 MV plans for the PTV dose assessment parameters and the homogeneity index of the plans for Group B. The monitor units (MUs) of the 10 MV plans were lower than in the 6 MV plans in both Groups A and B, and the difference was statistically significant. The assessment parameter V40 Gy of both the rectum and bladder in the 6 MV plans was smaller than the corresponding parameter in the 10 MV plans in Group A; in Group B, the assessment parameter V50 Gy of the rectum in the 10 MV plans was smaller than in the 6 MV plans. CONCLUSION: When T < 34 cm, 6 MV energy is more suitable for the external irradiation of cervical cancer. When T > 34 cm, 10 MV energy is more suitable for cervical cancer radiotherapy. Therefore, 10 MV should be considered for patients with a large abdominal size.
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Radioterapia de Intensidad Modulada , Neoplasias del Cuello Uterino , Humanos , Femenino , Radioterapia de Intensidad Modulada/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias del Cuello Uterino/radioterapia , Fotones/uso terapéuticoRESUMEN
To further improve the intrinsic reactivity of single-atom catalysts (SACs), the controllable modification of a single site by coordinating with a second neighboring metal atom, developing double-atom catalysts (DACs), affords new opportunities. Here we report a catalyst that features two bonded Fe-Co double atoms, which is well represented by an FeCoN6(OH) ensemble with 100% metal dispersion, that work together to switch the reaction mechanism in alcohol dehydrogenation under oxidant-free conditions. Compared with Fe-SAC and Co-SAC, FeCo-DAC displays higher activity performance, yielding the desired products in up to 98% yields. Moreover, a broad diversity of benzyl alcohols and aliphatic alcohols convert into the corresponding dehydrogenated products with excellent yields and high selectivity. The kinetic reaction results show that lower activation energy is obtained by FeCo-DAC than that by Fe-SAC and Co-SAC. Moreover, computational studies demonstrate that the reaction path by DACs is different from that by SACs, providing a rationale for the observed enhancements.
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Etanol , Metales , CatálisisRESUMEN
PURPOSE: To compare the dosimetric differences between intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) in the treatment of male and female thymoma. MATERIAL AND METHODS: This single-institutional analysis included 20 patients with thymoma treated with RT between January 2017 and December 2020. Twenty patients were retrospectively planned for IMRT (IMRT1 with an average field angle of 216°, 288°, 0°, 72°,and 144°; IMRT2 with fan-shaped field angles of 280°, 320°, 0°, 40°, and 80°) and VMAT (VMAT1 with two arcs ranging form 280° to 80°,clockwise and then counterclockwise; VMAT2 with two 360° arcs). The plans for all investigated RT modalities were optimized for a prescriptional dose of 50Gy and fractional dose of 2.0Gy. Planning target volume (PTV) and organs-at-risk (OARs: heart, breasts, lungs, spinal cord, and esophagus) dosimetric parameters were compared. RESULTS: All plans met the preparation aims for all the included metrics. There was little difference in the median values of PTV parameters (D2%, D98%, Dmean, homogeneity index[HI], and conformity index [CI]). The CI of the VMAT2 plan was the closest to 1 in both therapy groups. The monitor unit (MU) of IMRT2 and the estimated total delivery time of VMAT1 were the lowest in both therapy groups and were statistically significant. In the male group, the lung parameters (Dmean, V5Gy, V10Gy, and V20Gy) for VMAT1 were the lowest and showed statistical significance. In the female group, the lung parameters (Dmean, V5Gy, V10Gy, and V20Gy) and bilateral breast parameters (Dmean, V5Gy, V10Gy, and V20Gy) of IMRT2 were the lowest and showed statistical significance. CONCLUSIONS: In male thymoma patients undergoing postoperative RT (PORT) treatment, the choice of fan-shaped VMAT may be a better option for protecting the lungs. For female thymoma patients receiving PORT, fan-shaped IMRT can better protect the lungs and breasts. The fan-shaped field performed better than the average and the full arc fields in PORT for thymoma.
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Radioterapia de Intensidad Modulada , Timoma , Neoplasias del Timo , Femenino , Humanos , Masculino , Órganos en Riesgo , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/efectos adversos , Estudios Retrospectivos , Timoma/radioterapia , Timoma/cirugía , Neoplasias del Timo/radioterapia , Neoplasias del Timo/cirugíaRESUMEN
Newborns demonstrate innate abilities in coordinating their sensory and motor systems through reflexes. One notable characteristic is circular reactions consisting of self-generated motor actions that lead to correlated sensory and motor activities. This paper describes a model for goal-directed reaching based on circular reactions and exocentric reference-frames. The model is built using physiologically plausible visual processing modules and arm-control neural networks. The model incorporates map representations with ego- and exo-centric reference frames for sensory inputs, vector representations for motor systems, as well as local associative learning that result from arm explorations. The integration of these modules is simulated and tested in a three-dimensional spatial environment using Unity3D. The results show that, through self-generated activities, the model self-organizes to generate accurate arm movements that are tolerant with respect to various sources of noise.
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BACKGROUND: Sarcopenia has been associated with treatment-related toxicities and poor survival in cancer patients. Our aim was to investigate the prevalence of sarcopenia in postoperative recurrent esophageal squamous cell carcinoma (ESCC) patients receiving chemoradiotherapy (CRT) and evaluate associations with treatment-related toxicity and prognosis. METHODS: One hundred and eighty-four patients with postoperative locoregional recurrent ESCC receiving CRT between January 2014 and December 2016 were included. The skeletal muscle area (SMA) was measured at the third lumbar vertebra level. Sarcopenia was defined as skeletal muscle index (SMI = SMA/height2) less than 47.24/cm2/m2 for men and 36.92/cm2/m2 for women. Association of sarcopenia with overall survival (OS) was analyzed using univariate and multivariate cox regression models. RESULTS: Sarcopenia was observed in 94 of 184 (51.1%) patients. Sarcopenic patients had significantly higher rates of grade 3-4 toxicities compared to those without sarcopenia (36.2% vs 21.1%, p = 0.034). The survival rate at 12 and 24 months was 36.2% and 3.2% in the sarcopenic patients and 57.8% and 17.8% in the non-sarcopenic patients (p < 0.001). Multivariate cox regression analysis showed that sarcopenia was significantly associated with decreased OS (HR = 1.729, 95% CI 1.231-2.428, p = 0.002). CONCLUSIONS: Sarcopenia is an independent indicator of poor survival in postoperative locoregional recurrent ESCC patients treated with CRT. Early nutritional interventions before treatment may improve the prognosis.
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Cancer-associated fibroblasts (CAFs), an activated subpopulation of fibroblasts, occupy a central position in the tumor microenvironment and have been shown to promote chemoresistance in multiple cancer types by secreting inflammatory cytokines. Herein, we report that tumor-secreted exosomal long non-coding RNAs (lncRNAs) can regulate cisplatin resistance in esophageal squamous cell carcinoma (ESCC) through transformation of normal fibroblasts (NFs) to CAFs. Primary CAFs and matched NFs were isolated from tumor tissues and matched normal esophageal epithelial tissues of ESCC patients. Fluorescence microscopy and qRT-PCR were used to investigate the transportation of exosomal lncRNAs from ESCC cells to NFs. To identify the specific lncRNAs involved, 14 ESCC-related lncRNAs were measured in NFs after incubation with exosomes from ESCC cells. We demonstrated that lncRNA POU3F3 can be transferred from ESCC cells to NFs via exosomes and that it mediated fibroblast activation. Activated fibroblasts further promoted proliferation and cisplatin resistance of ESCC cells through secreting interleukin 6 (IL-6). Moreover, our clinical data showed that high levels of plasma exosomal lncRNA POU3F3 correlated significantly with lack of complete response and poor survival in ESCC patients. Therefore, these data demonstrate that lncRNA POU3F3 is involved in cisplatin resistance in ESCC and that this effect is mediated through exosomal lncRNA POU3F3-induced transformation of NFs to CAFs.
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The present study evaluated the clinical and prognostic value of neutrophil-to-lymphocyte ratio (NLR) in patients with locally advanced esophageal squamous cell carcinoma (ESCC) treated with definitive chemoradiotherapy (dCRT). A total of 517 patients with ESCC were enrolled and analysed retrospectively. The NLR was calculated at three time points: baseline, post-treatment, and at the time of tumor progression. Elevated NLR was defined as a ratio ≥5. High NLR at baseline was present in 204 (39%) patients and was significantly correlated with larger tumour size, advanced TNM stage, worse ECOG performance status, and dCRT response (p < 0.05). At a median follow-up of 17 months, patients with higher NLR at baseline had poorer progression-free survival (PFS) and overall survival (OS). On multivariate analysis, elevated NLR at baseline was independently associated with PFS and OS (HR = 1.529, p < 0.001 for PFS; HR = 1.856, p < 0.001 for OS). In addition, patients with high pre- and post-treatment NLR demonstrated worse clinical outcomes than other groups. Our results suggest that NLR is an independent prognostic indicator for patients with ESCC undergoing dCRT and changes in NLR level with treatment may indicate therapeutic benefit.