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Molecule-inclusive closed cage compounds present a unique platform for molecular motion in an isolated environment. This study showcases the incorporation of a tadpole-like polar molecule (1-propyl-1H-imidazole, PIm) into a supramolecular cage formed by duad semicage p-tert-butylcalix[4]arene. The ferroelectric phase transition as well as the cage-confined motion of encapsulated PIm was studied in detail. The unusual quadrastable state of the PIm in the paraelectric phase allows for the modulation of dipolar polarization over a broad temperature/frequency range. This compound represents the first example of a clathrate molecular ferroelectric featuring a molecule-inclusive supramolecular cage, and it also contributes to the understanding of cage-confined molecular dynamics.
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Background and objectives: The intercornual distance in the sacral hiatus has yet to be studied precisely in children. This age-stratified, observational study aimed to clarify the changes in sacral hiatus dimensions and to quantify the correlations between the intercornual distance of the sacral hiatus and age, height, weight, and head circumference by using real-time ultrasonography. Methods: The patients were stratified into three groups: neonates and infants, toddlers, and schoolchildren. In the operating room, the ultrasonic probe was placed at the sacral cornua to obtain a transverse view of the sacral hiatus, and the intercornual distance was measured three times in millimetres. Results: The study included a total of 156 patients. The mean ± SD (95%CI) of intercornual distance in neonates and infants (<12 months) was 11.58 ± 1.79 (11.11-12.04) mm, 13.29 ± 1.97 (12.71-13.86) mm in toddlers (13-36 months), and 13.36 ± 2.49 (12.64-14.08) mm in schoolchildren (>36 months).The mean values of neonates and infants were different from those of toddlers and schoolchildren (p < 0.001), but it was similar between toddlers and schoolchildren (p > 0.05, 95 % CI mean difference -1.10 to 0.95).Intercornual distance was correlated with age, height, weight, and head circumference before one year of age (Spearman's R values > 0.7), but there was no correlation thereafter (Spearman's p value > 0.05). Conclusion: In the first year after birth, the intercornual distance increases rapidly with body growth; after one year of age, the sacral hiatus dimension changes significantly. Ultrasound is superior for assessing the gradually ossified cartilage components in older children.
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BACKGROUND: The effects of heat acclimation (HA) on the hypothalamus after exertional heatstroke (EHS) and the specific mechanism have not been fully elucidated, and this study aimed to address these questions. METHODS: In the present study, rats were randomly assigned to the control, EHS, HA, or HA + EHS groups (n = 9). Hematoxylin and eosin (H&E) staining was used to examine pathology. Tandem mass tag (TMT)-based proteomic analysis was utilized to explore the impact of HA on the protein expression profile of the hypothalamus after EHS. Bioinformatics analysis was used to predict the functions of the differentially expressed proteins. The differential proteins were validated by western blotting. An enzyme-linked immunosorbent assay was used to measure the expression levels of inflammatory cytokines in the serum. RESULTS: The H&E staining (n = 5) results revealed that there were less structural changes in hypothalamus in the HA + EHS group compared with the EHS group. Proteomic analysis (n = 4) revealed that proinflammatory proteins such as argininosuccinate synthetase (ASS1), high mobility group protein B2 (HMGB2) and vimentin were evidently downregulated in the HA + EHS group. The levels of interleukin (IL)-1ß, IL-1, and IL-8 were decreased in the serum samples (n = 3) from HA + EHS rats. CONCLUSIONS: HA may alleviate hypothalamic damage caused by heat attack by inhibiting inflammatory activities, and ASS1, HMGB2 and vimentin could be candidate factors involved in the exact mechanism.
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Golpe de Calor , Hipotálamo , Proteómica , Ratas Sprague-Dawley , Animales , Hipotálamo/metabolismo , Golpe de Calor/metabolismo , Ratas , Masculino , Esfuerzo Físico/fisiología , Modelos Animales de EnfermedadRESUMEN
Hybrid ferroelastic crystals have emerged as a hot research topic in recent years owing to their prospective applications in piezoelectric sensors, mechanical switches, and optoelectronic devices. Nevertheless, most of the documented materials exhibit one-step or two-step ferroelastic phase transition(s), and those with multistep ferroelastic transitions are extremely scarce. We present a new hexagonal molecular perovskite based on a fluoro-substituted flexible cyclic ammonium cation, (1-fluoromethyl-1-methylpyrrolidine)[CdCl3] (1), undergoing unusual three-step ferroelastic phase transitions from hexagonal paraelastic phase to orthorhombic, monoclinic, and triclinic ferroelastic phases at 388, 376, and 311 K, respectively, with Aizu notation of 6/mmmFmmm, mmmF2/m, and 2/mF-1, featuring spontaneous strain of 0.002, 0.023, and 0.110, respectively. Furthermore, variable-temperature single-crystal diffraction reveals that the phase-transition mechanism in 1 principally originates from intriguing dynamic change of organic cations and synchronous displacement of inorganic chains. This scarce instance of multistep hybrid ferroelastic provides important clues for finding advanced ferroelastic materials.
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Thermal insulation materials with good flame-retardant properties have attracted widespread attention because of their huge application potential. Traditional petrochemical-based polymer insulation materials are flammable and have problems with environmental pollution. The microtubule structure is a perfect microstructure with excellent thermal insulation performance. In addition, the microtubule structure also has low density and high elasticity. Therefore, the microtubule structure is an important reference microstructure for the development of efficient thermal insulation materials. In this paper, a cellulose/SiO2 composite microtube thermal insulation superfoam has been successfully prepared. Cellulose microtubules were successfully prepared from poplar sawdust by chemical methods. The SiO2 aerogel precursor solution can be quickly adsorbed by the delignified cellulose microtubes. The SiO2 aerogel shells are evenly distributed only on the inner and outer walls of the delignified cellulose microtubes. The cellulose/SiO2 microtube composite (CSMC) superfoam exhibits low density, good mechanical properties, and low thermal conductivity (as low as 0.042 ± 0.0018 W m-1 K-1). The CSMC superfoam exhibits excellent self-extinguishing and flame-retardant properties. After being burned by a butane flame, the superfoam still has certain mechanical properties. The thermal conductivity of the B-CSMC superfoam (the CSMC superfoam burned by a butane flame) is about 0.050 W m-1 K-1. The B-CSMC superfoam remained almost unchanged after being continuously ablated by a butane flame for 3600 seconds.
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High-performance thermal insulation materials with broad application prospects have attracted great attention. The introduction of new microstructures into thermal protection materials can significantly improve the thermal insulation performance. The tubular microstructure has obvious advantages such as thermal insulation, lightweight, mechanical, and other properties. Therefore, the microtubular structure has become an important reference microstructure for the development of high-performance thermal insulation materials. In this paper, the carbon/ZrO2 aerogel composite microtube superfoams with excellent thermal protection properties were prepared by a vacuum filtration and high-temperature carbonization method. The ZrO2 aerogel precursor solution can be quickly and uniformly adsorbed on the inner and outer walls of cellulose microtubules. These adsorbed ZrO2 aerogel precursor solution films can be converted into ZrO2 alcohol gel shells under the acceleration and promotion effect of citric acid at 65 °C. The micromorphology of the ZrO2 aerogel shell on the inner and outer walls of the composite microtubes can be efficiently controlled by the concentration of the ZrO2 aerogel precursor solution and the carbonization temperature. The carbon/ZrO2 aerogel composite microtube superfoam exhibits a lower thermal conductivity, lower density, good mechanical properties, and high ablation resistance. The thermal conductivity of the carbon/ZrO2 aerogel composite microtube superfoam is as low as 0.040 ± 0.001 W m-1 K-1. The residual rate of the carbon/ZrO2 aerogel composite microtube superfoam is still as high as 84.33% after butane flame ablation for up to 3600 seconds.
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PURPOSE: This aim of this study was to compare two anesthetic regimens in terms of extubation time and postoperative recovery in children undergoing ambulatory adenoidectomy. DESIGN: A retrospective cohort study with propensity score matching. METHODS: The medical charts of 452 children aged between 3 and 8 years undergoing ambulatory adenoidectomy were retrieved for analysis, of which 438 were eligible to participate in this study. A majority (n = 327) were children exposed to a conventional propofol-pronounced general anesthetic regimen (high-dose propofol plus low-dose remifentanil, labeled as group P), while n = 111 were administered a modified remifentanil-pronounced anesthetic regimen (low-dose propofol plus high-dose remifentanil, namely group R). Propensity score matching was employed to adjust for confounders, resulting in 69 matched patients in each group. The primary endpoint of this study was extubation time. The secondary endpoints were total intraoperative fluid volume, length of stay in the postanesthesia care unit (PACU), postoperative pain rating, the incidence of emergence agitation, nausea and vomiting, as well as the level of consciousness (fully awake or waking by gentle patting) when transferred out of PACU, and any major complications (wound bleeding, reintubation, readmission, and overnight stay). FINDINGS: No major complications were observed in both groups. Compared to group P, group R had significantly shorter extubation time (8.2 ± 1.4 minutes vs 13.3 ± 2.4 minutes, P < .001), shorter length of stay in the PACU (14.1 ± 3.1 minutes vs 20.2 ± 3.4 minutes, P < .001), and a higher proportion of cases being fully awake when transferred out of the PACU (91% vs 46%, P < .001). Lastly, the pain rating, frequency of oropharyngeal airway usage, incidence of emergence agitation, and nausea and vomiting were comparable between the two groups (P > .05 for all). CONCLUSIONS: Remifentanil-pronounced anesthesia was superior to propofol-pronounced anesthesia in children undergoing ambulatory adenoidectomy, given that the former was associated with a faster recovery time from anesthesia without jeopardizing patient safety.
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Delirio del Despertar , Propofol , Niño , Humanos , Preescolar , Remifentanilo , Anestésicos Intravenosos , Estudios Retrospectivos , Adenoidectomía , Extubación Traqueal , Anestesia General , Vómitos , Náusea , Periodo de Recuperación de la AnestesiaRESUMEN
Sleep disturbance is a recognized risk factor for Alzheimer's disease (AD), but the underlying micro-pathological evidence remains limited. To bridge this gap, we established an amyloid-ß oligomers (AßO)-induced rat model of AD and subjected it to intermittent sleep deprivation (SD). Diffusion tensor imaging (DTI) and transmission electron microscopy were employed to assess white matter (WM) integrity and ultrastructural changes in myelin sheaths. Our findings demonstrated that SD exacerbated AßO-induced cognitive decline. Furthermore, we found SD aggravated AßO-induced asymmetrical impairments in WM, presenting with reductions in tract integrity observed in commissural fibers and association fasciculi, particularly the right anterior commissure, right corpus callosum, and left cingulum. Ultrastructural changes in myelin sheaths within the hippocampus and corpus callosum further confirmed a lateralized effect. Moreover, SD worsened AßO-induced lateralized disruption of the brain structural network, with impairments in critical nodes of the left hemisphere strongly correlated with cognitive dysfunction. This work represents the first identification of a lateralized impact of SD on the mesoscopic network and cognitive deficits in an AD rat model. These findings could deepen our understanding of the complex interplay between sleep disturbance and AD pathology, providing valuable insights into the early progression of the disease, as well as the development of neuroimaging biomarkers for screening early AD patients with self-reported sleep disturbances. Enhanced understanding of these mechanisms may pave the way for targeted interventions to alleviate cognitive decline and improve the quality of life for individuals at risk of or affected by AD.
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Enfermedad de Alzheimer , Sustancia Blanca , Humanos , Ratas , Animales , Sustancia Blanca/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Privación de Sueño/complicaciones , Privación de Sueño/patología , Calidad de VidaRESUMEN
BACKGROUND: The artificial anal sphincter (AAS) system has gained significant attention as a solution for treating fecal incontinence (FI). It relies on transcutaneous energy transfer (TET) as its primary energy source. However, changes in posture or biological tissue can cause misalignment of the coil, resulting in unstable power reception. Inadequate power affects charging efficiency, while excessive power leads to excessive heating at the receiver side. Consequently, achieving safe and constant voltage charging for the AAS becomes a complex challenge. METHODS: To maintain a consistent charging voltage and overcome the issue of variations in load and coil coupling strength, this article proposes a wireless charging control system that utilizes an LCC-S-type resonant network and phase shift to adjust the transmitting voltage based on feedback charging voltage in real time. In particular, the PI controller and neural network are introduced to change the phase-shift angle swiftly. The dynamic performance is then evaluated under different misalignments and presented with comparative results. RESULTS: The results indicate that the multilayer perceptron control system outperforms the PI. Under the complex misalignment disturbance, the average error of receiver side load voltage is only 0.007 V, with an average settling time of 960 ms. Additionally, the average temperature at the receiver side is 40.4°C. CONCLUSION: The experiments demonstrate that the proposed system effectively addresses the misalignment issue in TET during the charging, ensuring constant voltage charging at the receiver side and thermal safety.
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Órganos Artificiales , Esfínter Urinario Artificial , Canal Anal/cirugía , Transferencia de Energía , Redes Neurales de la ComputaciónRESUMEN
BACKGROUND: Limited data exist regarding the use of the esketamine-propofol combination (esketofol) in pediatric surgery. This study aimed to investigate the effect of esketofol versus propofol alone on the perioperative characteristics of children undergoing minor surgery. METHODS: Eighty-four children aged two to six years were randomly assigned to either the propofol group or the esketofol group. Intraoperative outcomes included bispectral index, dosage of anesthetics, and extubation time. Postoperative outcomes comprised oropharyngeal airway usage, time to orientation, time to eye-opening, length of stay in the post-anesthesia care unit, the need for rescue opioids, pain rating using the Face, Legs, Activity, Cry, Consolability (FLACC) Scale, Pediatric Anesthesia Emergence Delirium Score, nausea and vomiting, and psychotomimetic symptoms. The FLACC pain score was the primary outcome, and the remaining parameters were considered secondary outcomes. RESULTS: The FLACC Score (2 [1, 3.3] vs. 4 [3, 5.3], P<0.001) and frequency of rescue opioids (14.3% vs. 33.3%, P=0.040) were significantly lower, while Bispectral Index (BIS) was higher (P<0.001) in the esketofol group compared with the propofol group. Moreover, the time to orientation and length of stay in the post-anesthesia care unit (PACU) were significantly longer in the esketofol group compared with the propofol group (P=0.029 and P=0.025, respectively). The other outcomes were similar between the two groups. CONCLUSIONS: Esketofol reduces postoperative pain and the need for rescue opioids, but it extends recovery time in the PACU and increases BIS without affecting other outcomes.
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Ketamina , Propofol , Humanos , Niño , Anestésicos Intravenosos , Estudios Prospectivos , Dolor Postoperatorio , Analgésicos OpioidesRESUMEN
Oscillations, commonly known as a universal, propagative, and intricate event in the new power system, often give rise to generator tripping and load shedding, not only adversely affecting the power flow limit and the power angle stability but also posing threats to the lines of defense for stability and protection. Traditionally, emphasis has been laid on post-fault oscillation management, an emergency measure to deal with the impact and damage that have already affected the power grid. As such, this paper focuses on an oscillation prediction technique to detect oscillation energy early and intervene proactively to prevent further faults. This technique effectively lessens the damage caused by impacts and disconnects to the power grid. Firstly, this paper proposes the concept of disturbance power density and establishes the correlation between disturbance energy and the time domain, thereby exploring a method for evaluating the pattern of electrical quantities before power system oscillation. Secondly, it speeds up the time it takes to detect faults by catching nuances of voltage-current phase angle and impedance. Lastly, it puts forward a technique to cope with the intricacy and variety of power grid equipment using the convolutional neural network (CNN). This technique incorporates an integrated attention mechanism within a one-dimensional CNN model to capture the implicit mapping between voltage, active power, and reactive power at any time in the power system. This enables the model to self-learn multi-device characteristics and enhances the possibility of using theory in practical ways. Moreover, practical case studies also show that the prediction technique proposed in this paper can effectively issue warnings eight minutes before the occurrence of oscillation.
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In order to achieve goat localization to help prevent goats from wandering, we proposed an efficient target localization method based on machine vision. Albas velvet goats from a farm in Ertok Banner, Ordos City, Inner Mongolia Autonomous Region, China, were the main objects of study. First, we proposed detecting the goats using a shallow convolutional neural network, ShallowSE, with the channel attention mechanism SENet, the GeLU activation function and layer normalization. Second, we designed three fully connected coordinate regression network models to predict the spatial coordinates of the goats. Finally, the target detection algorithm and the coordinate regression algorithm were combined to localize the flock. We experimentally confirmed the proposed method using our dataset. The proposed algorithm obtained a good detection accuracy and successful localization rate compared to other popular algorithms. The overall number of parameters in the target detection algorithm model was only 4.5 M. The average detection accuracy reached 95.89% and the detection time was only 8.5 ms. The average localization error of the group localization algorithm was only 0.94 m and the localization time was 0.21 s. In conclusion, the method achieved fast and accurate localization, which helped to rationalize the use of grassland resources and to promote the sustainable development of rangelands.
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For quite a long time, researches on Alzheimer's disease (AD) primarily focused on the cortex and hippocampus, while the cerebellum has been ignored because of its abnormalities considered to appear in the late stage of AD. In recent years, increasing evidence suggest that the cerebellar pathological changes possibly occur in the preclinical phase of AD, which is also associated with sleep disorder. Sleep disturbance is a high risk factor of AD. However, the changes and roles of cerebellum has rarely been reported under conditions of AD accompanied with sleep disorders. In this study, using an amyloid-ß oligomers (AßO)-induced rat model of AD subjected to sleep deprivation, combining with a 7.0 T animals structural magnetic resonance imaging (MRI), we assessed structural changes of cerebellum in MRI. Our results showed that sleep deprivation combined with AßO led to an increased FA value in the anterior lobe of cerebellum, decreased ADC value in the cerebellar lobes and cerebellar nuclei, and increased cerebellum volume. Besides that, sleep deprivation exacerbated the damage of AßO to the cerebellar structural network. This study demonstrated that sleep deprivation could aggravate the damage to cerebellum induced by AßO. The present findings provide supporting evidence for the involvement of cerebellum in the early pathology of AD and sleep loss. Our data would contribute to advancing the understanding of the mysterious role of cerebellum in AD and sleep disorders, as well as would be helpful for developing non-invasive MRI biomarkers for screening early AD patients with self-reported sleep disturbances.
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OBJECTIVE: This study aimed to evaluate the visual performance and image quality of concentric dual-focus-designed contact lenses (CLs) compared with single-vision CLs in myopic Chinese people. METHODS: Twenty myopic volunteers aged between 18 and 26 years were recruited at a university eye hospital to wear both defocus-incorporated soft contact (DISC) lenses and single-vision CLs for 1 week in random order. High- and low-contrast visual acuity (VA), contrast sensitivity (CS), ocular higher-order aberrations (HOA), Strehl ratio and the Quality of Vision (QoV) questionnaire were assessed with each type of CL at weekly follow-up. RESULTS: Distance VA was not affected by DISC lenses compared to single-vision CLs in either high (p = 0.414) or low contrast (p = 0.431). However, there was a significant reduction in low-contrast near VA with DISC lenses compared with single-vision CLs (p = 0.011). The differences of CS between DISC lenses and single-vision CLs were significantly associated with lighting conditions and spatial frequencies (F = 128.81, P < 0.001). Compared with single-vision CLs, wavefront aberrations of DISC lenses were significantly increased in total HOA, trefoil, and spherical aberrations for either 3.0 mm or 6.0 mm pupil size. The Strehl ratio wearing DISC lenses reduced significantly compared to the single-vision CLs (p < 0.001) at a pupil diameter of 6.0 mm. QoV scores were higher overall (p = 0.026) and frequency (p = 0.019) with DISC lenses than with single-vision CLs, indicating poorer visual performance. CONCLUSION: DISC lenses provide satisfactory distance VA. However, the higher scores of the QoV questionnaire with DISC lenses may be related to decreased CS at medium or high spatial frequencies and increased higher-order aberrations.
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Lentes de Contacto Hidrofílicos , Miopía , Humanos , Sensibilidad de Contraste , Miopía/terapia , Trastornos de la Visión , Visión Ocular , Agudeza Visual , Adolescente , Adulto Joven , AdultoRESUMEN
Organic-inorganic hybrid metal halides for high-temperature phase transition have become increasingly popular owing to their wide operating temperature range in practical applications, e.g., energy storage, permittivity switches and opto-electronic devices. This paper describes the subtle assembly of two new hybrid perovskite crystals, [Cl-C6H4-(CH2)2NH3]2CdX4 (X = Br 1; Cl 2), undergoing high-T reversible phase transformations around 335 K/356 K. Differential scanning calorimetry (DSC), differential thermal analysis (DTA) and VT PXRD tests uncover their reversible first-order phase transition behaviors. Furthermore, the compounds exhibit switchable dielectricity near T, making them potential dielectric switching materials. Hirshfeld surface analysis well discloses a distinct difference in hydrogen-bonding interaction between 1 and 2. UV spectra and computational analysis demonstrate that the compounds are a type of direct-band-gap semiconductor. This research will contribute an effective approach to the structure and development of multifunctional molecular hybrid crystals.
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With the advancement of deep learning technology, the importance of utilizing deep learning for livestock management is becoming increasingly evident. goat face detection provides a foundation for goat recognition and management. In this study, we proposed a novel neural network specifically designed for goat face object detection, addressing challenges such as low image resolution, small goat face targets, and indistinct features. By incorporating contextual information and feature-fusion complementation, our approach was compared with existing object detection networks using evaluation metrics such as F1-Score (F1), precision (P), recall (R), and average precision (AP). Our results show that there are 8.07%, 0.06, and 6.8% improvements in AP, P, and R, respectively. The findings confirm that the proposed object detection network effectively mitigates the impact of small targets in goat face detection, providing a solid basis for the development of intelligent management systems for modern livestock farms.
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BACKGROUND: Exertional heatstroke (EHS) is an emergency with a high mortality rate, characterized by central nervous system dysfunctions. This study aims to establish a Heat acclimation/acclimatization (HA) rat model in locomotion to recapitulate the physical state of human in severe environment of high temperature and humidity, and investigate the mechanism of organism protection in HA. (2) Methods: Wistar rats were exposed to 36 °C and ran 2 h/d for 21 days, acquired thermal tolerance test was conducted to assess the thermotolerance and exercise ability. Core temperature and consumption of water and food were observed. Expression of HSP70 and HSP90 of different tissues were determined by WB. Pathological structure of brain tissue was detected with HE staining. Proteomics was used to identify the differently expressed proteins in cerebral cortex of different groups. And key molecules were identified by RT-PCR and WB. (3) Results: HA rats displayed stronger thermotolerance and exercised ability on acquired thermal tolerance test. Brain water content of HA + EHS group reduced compared with EHS group. HE staining revealed slighter brain injuries of HA + EHS group than that of EHS. Proteomics focused on cell death-related pathways and key molecules Aquaporin 4 (AQP4) related to cell edema. Identification results showed HA increased AQP4, Bcl-xl, ratio of p-Akt/AKT and Bcl-xl/Bax, down-regulated Cleaved Caspase-3. (4) Conclusions: This HA model can ameliorate brain injury of EHS by reducing cerebral edema and cell apoptosis, offering experimental evidence for EHS prophylaxis.
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Lesiones Encefálicas , Golpe de Calor , Humanos , Ratas , Animales , Proteínas Proto-Oncogénicas c-akt , Ratas Wistar , Respuesta al Choque Térmico , Aclimatación/fisiología , Ejercicio Físico/fisiologíaAsunto(s)
Tubos Torácicos , Bloqueo Neuromuscular , Humanos , Sugammadex , Rocuronio , Cirugía Torácica Asistida por Video , Neostigmina , DrenajeRESUMEN
Due to the fascinating features, pulsating solitons attract much attention in the field of nonlinear soliton dynamics and ultrafast lasers. So far, most of the investigations on pulsating soliton are conducted in Er-doped fiber lasers. In this work, we reported the periodic transition between two evolving pulsating soliton states in an Yb-doped fiber laser. By using the real-time measurement techniques, the spectral and temporal characteristics of this transition state were investigated. Two evolving soliton pulsation states have similar evolution process, i.e., from pulsating towards quasi-stable mode-locked states. However, the details of the two processes are different, such as the pulse energy levels, pulsating modulation depths, duration of quasi-stable mode-locked states. The transition between two evolving soliton pulsation states could be attributed to the interaction of the polarizer and the varying polarization states of the pulse inside the laser cavity. The experimental results will contribute to the further understanding of soliton pulsating dynamics in dissipative optical systems.