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We present analytical results of the fundamental properties of the one-dimensional (1D) Hubbard model with a repulsive interaction. The new model results with arbitrary external fields include: (I) using the exact solutions of the Bethe ansatz equations of the Hubbard model, we first rigorously calculate the gapless spin and charge excitations, exhibiting exotic features of fractionalized spinons and holons. We then investigate the gapped excitations in terms of the spin string and thek-Λstring bound states at arbitrary driving fields, showing subtle differences in spin magnons and chargeη-pair excitations. (II) For a high-density and high spin magnetization region, i.e. near the quadruple critical point, we further analytically obtain the thermodynamic properties, dimensionless ratios and scaling functions near quantum phase transitions. (III) Importantly, we give the general scaling functions at quantum criticality for arbitrary filling and interaction strength. These can directly apply to other integrable models. (IV) Based on the fractional excitations and the scaling laws, the spin-incoherent Luttinger liquid (SILL) with only the charge propagation mode is elucidated by the asymptotic of the two-point correlation functions with the help of conformal field theory. We also, for the first time, obtain the analytical results of the thermodynamics for the SILL. (V) Finally, to capture deeper insights into the Mott insulator and interaction-driven criticality, we further study the double occupancy and propose its associated contact and contact susceptibilities, through which an adiabatic cooling scheme based upon quantum criticality is proposed. In this scenario, we build up general relations among arbitrary external- and internal-potential-driven quantum phase transitions, providing a comprehensive understanding of quantum criticality. Our methods offer rich perspectives of quantum integrability and offer promising guidance for future experiments with interacting electrons and ultracold atoms, both with and without a lattice.
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Strong near-field enhancements (NFEs) of nanophotonic structures are believed to be closely related to high Purcell factors (FP). Here, we theoretically show that the correlation is partially correct; the extinction cross section (σ) response is also critical in determining FP. The divergence between NFE and FP is especially pronounced in plasmonic-dielectric hybrid systems, where the plasmonic antenna supports dipolar plasmon modes and the dielectric cavity hosts Mie-like resonances. The cavity's enhanced-field environment can boost the antenna's NFEs, but the FP is not increased concurrently due to the larger effective σ that is intrinsic to the FP calculations. Interestingly, the peak FP for the coupled system can be predicted by using the NFE and σ responses. Furthermore, the limits for FP of coupled systems are considered; they are determined by the sum of the FP of a redshifted (or modified, if applicable) antenna and an individual cavity. This contrasts starkly with the behavior of NFE which is closely associated with the multiplicative effects of the NFEs provided by the antenna and the dielectric cavity. The differing behaviors of NFE and FP in hybrid cavities have varied impacts on relevant nanophotonic applications such as fluorescence, Raman scattering and enhanced light-matter interactions.
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Quantum many-body interactions can induce quantum entanglement among particles, rendering them valuable resources for quantum-enhanced sensing. In this work, we establish a link between the bound on the growth of the quantum Fisher information and the Lieb-Robinson bound, which characterizes the operator growth in locally interacting quantum many-body systems. We show that for initial separable states, despite the use of local many-body interactions, the precision cannot surpass the shot noise limit at all times. This conclusion also holds for an initial state that is the nondegenerate ground state of a local and gapped Hamiltonian. These findings strongly hint that when one can only prepare separable initial states, nonlocal and long-range interactions are essential resources for surpassing the shot noise limit. This observation is confirmed through numerical analysis on the long-range Ising model. Our results bridge the field of many-body quantum sensing and operator growth in many-body quantum systems and open the possibility to investigate the interplay between quantum sensing and control, many-body physics and information scrambling.
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This study reports a metal- and light-free decarboxylative C-H alkylation of heteroarenes at room temperature. The reaction generates various primary, secondary, and tertiary alkyl radicals and functionalizes seven different privileged scaffolds widely present in bioactive molecules. During this process, one equivalent of hypervalent iodine(III) carboxylates (HICs) plays dual roles as an alkyl radical precursor and an oxidant.
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Neuropathic pain is a common dose-limiting side effect of oxaliplatin, which hampers the effective treatment of tumors. Here, we found that upregulation of transcription factor NFATc2 decreased the expression of Beclin-1, a critical molecule in autophagy, in the spinal dorsal horn, and contributed to neuropathic pain following oxaliplatin treatment. Meanwhile, manipulating autophagy levels by intrathecal injection of rapamycin (RAPA) or 3-methyladenine (3-MA) differentially altered mechanical allodynia in oxaliplatin-treated or naïve rats. Utilizing chromatin immunoprecipitation-sequencing (ChIP-seq) assay combined with bioinformatics analysis, we found that NFATc2 negatively regulated the transcription of tuberous sclerosis complex protein 2 (TSC2), which contributed to the oxaliplatin-induced Beclin-1 downregulation. Further assays revealed that NFATc2 regulated histone H4 acetylation and methylation in the TSC2 promoter site 1 in rats' dorsal horns with oxaliplatin treatment. These results suggested that NFATc2 mediated the epigenetic downregulation of the TSC2/Beclin-1 autophagy pathway and contributed to oxaliplatin-induced mechanical allodynia, which provided a new therapeutic insight for chemotherapy-induced neuropathic pain.
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Neuralgia , Esclerosis Tuberosa , Animales , Ratas , Beclina-1/genética , Beclina-1/metabolismo , Beclina-1/farmacología , Modelos Animales de Enfermedad , Regulación hacia Abajo/genética , Epigénesis Genética , Hiperalgesia/inducido químicamente , Hiperalgesia/genética , Hiperalgesia/tratamiento farmacológico , Neuralgia/inducido químicamente , Neuralgia/genética , Neuralgia/tratamiento farmacológico , Oxaliplatino , Ratas Sprague-Dawley , Asta Dorsal de la Médula Espinal/metabolismo , Factores de Transcripción/metabolismo , Esclerosis Tuberosa/metabolismoRESUMEN
High glucose (HG) is one of the basic factors of diabetic nephropathy (DN), which leads to high morbidity and disability. During DN, the expression of glomerular glucose transporter 1 (GLUT1) increases, but the relationship between HG and GLUT1 is unclear. Glomerular mesangial cells (GMCs) have multiple roles in HG-induced DN. Here, we report prominent glomerular dysfunction, especially GMC abnormalities, in DN mice, which is closely related to GLUT1 alteration. In vivo studies have shown that BBR can alleviate pathological changes and abnormal renal function indicators of DN mice. In vitro, BBR (30, 60 and 90 µmol/L) not only increased the proportion of G1 phase cells but also reduced the proportion of S phase cells under HG conditions at different times. BBR (60 µmol/L) significantly reduced the expression of PI3K-p85, p-Akt, p-AS160, membrane-bound GLUT1 and cyclin D1, but had almost no effect on total protein. Furthermore, BBR significantly declined the glucose uptake and retarded cyclin D1-mediated GMC cell cycle arrest in the G1 phase. This study demonstrated that BBR can inhibit the development of DN, which may be due to BBR inhibiting the PI3K/Akt/AS160/GLUT1 signalling pathway to regulate HG-induced abnormal GMC proliferation and the cell cycle, supporting BBR as a potential therapeutic drug for DN.
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Berberina , Diabetes Mellitus , Nefropatías Diabéticas , Animales , Berberina/farmacología , Ciclo Celular , División Celular , Proliferación Celular , Diabetes Mellitus/patología , Nefropatías Diabéticas/patología , Glucosa/metabolismo , Transportador de Glucosa de Tipo 1/genética , Transportador de Glucosa de Tipo 1/metabolismo , Células Mesangiales/metabolismo , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
Over the past two decades quantum engineering has made significant advances in our ability to create genuine quantum many-body systems using ultracold atoms. In particular, some prototypical exactly solvable Yang-Baxter systems have been successfully realized allowing us to confront elegant and sophisticated exact solutions of these systems with their experimental counterparts. The new experimental developments show a variety of fundamental one-dimensional (1D) phenomena, ranging from the generalized hydrodynamics to dynamical fermionization, Tomonaga-Luttinger liquids, collective excitations, fractional exclusion statistics, quantum holonomy, spin-charge separation, competing orders with high spin symmetry and quantum impurity problems. This article briefly reviews these developments and provides rigorous understanding of those observed phenomena based on the exact solutions while highlighting the uniqueness of 1D quantum physics. The precision of atomic physics realizations of integrable many-body problems continues to inspire significant developments in mathematics and physics while at the same time offering the prospect to contribute to future quantum technology.
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BACKGROUND: Glioma is the most common brain malignant tumor, with a high morbidity rate and a mortality rate of more than three percent, which seriously endangers human health. The main method of acquiring brain tumors in the clinic is MRI. Segmentation of brain tumor regions from multi-modal MRI scan images is helpful for treatment inspection, post-diagnosis monitoring, and effect evaluation of patients. However, the common operation in clinical brain tumor segmentation is still manual segmentation, lead to its time-consuming and large performance difference between different operators, a consistent and accurate automatic segmentation method is urgently needed. With the continuous development of deep learning, researchers have designed many automatic segmentation algorithms; however, there are still some problems: (1) The research of segmentation algorithm mostly stays on the 2D plane, this will reduce the accuracy of 3D image feature extraction to a certain extent. (2) MRI images have gray-scale offset fields that make it difficult to divide the contours accurately. METHODS: To meet the above challenges, we propose an automatic brain tumor MRI data segmentation framework which is called AGSE-VNet. In our study, the Squeeze and Excite (SE) module is added to each encoder, the Attention Guide Filter (AG) module is added to each decoder, using the channel relationship to automatically enhance the useful information in the channel to suppress the useless information, and use the attention mechanism to guide the edge information and remove the influence of irrelevant information such as noise. RESULTS: We used the BraTS2020 challenge online verification tool to evaluate our approach. The focus of verification is that the Dice scores of the whole tumor, tumor core and enhanced tumor are 0.68, 0.85 and 0.70, respectively. CONCLUSION: Although MRI images have different intensities, AGSE-VNet is not affected by the size of the tumor, and can more accurately extract the features of the three regions, it has achieved impressive results and made outstanding contributions to the clinical diagnosis and treatment of brain tumor patients.
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Neoplasias Encefálicas/diagnóstico por imagen , Glioma/diagnóstico por imagen , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Neoplasias Encefálicas/patología , Aprendizaje Profundo , Glioma/patología , HumanosRESUMEN
Recent experiments on quantum walks (QWs) demonstrated a full control over the statistics-dependent walks of single particles and two particles in one-dimensional lattices. However, little is known about the general characterization of QWs at the many-body level. Here, we rigorously study QWs, Bloch oscillations, and the quantum Fisher information for three indistinguishable bosons and fermions in one-dimensional lattices using a time-evolving block decimation algorithm and many-body perturbation theory. We show that such strongly correlated QWs not only give rise to statistics-and-interaction-dependent ballistic transports of scattering states and of two- and three-body bound states but also allow a quantum enhanced precision measurement of the gravitational force. In contrast to the QWs of the fermions, the QWs of three bosons exhibit strongly correlated Bloch oscillations, which present a surprising time scaling t^{3} of the Fisher information below a characteristic time t_{0} and saturate to the fundamental limit of t^{2} for t>t_{0}.
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At low temperature, collective excitations of one-dimensional (1D) interacting fermions exhibit spin-charge separation, a unique feature predicted by the Tomonaga-Luttinger liquid (TLL) theory, but a rigorous understanding remains challenging. Using the thermodynamic Bethe ansatz (TBA) formalism, we analytically derive universal properties of a 1D repulsive spin-1/2 Fermi gas with arbitrary interaction strength. We show how spin-charge separation emerges from the exact TBA formalism, and how it is disrupted by the interplay between the two degrees of freedom that brings us beyond the TLL paradigm. Based on the exact low-lying excitation spectra, we further evaluate the spin and charge dynamical structure factors (DSFs). The peaks of the DSFs exhibit distinguishable propagating velocities of spin and charge as functions of interaction strength, which can be observed by Bragg spectroscopy with ultracold atoms.
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Conditioned place preference (CPP) is a learned behavior, in which animals learn to associate environmental contexts with rewarding effects. The formation of CPP is an integrated outcome of multiple learning processes. Although multiple anatomical substrates underlying this contextual learning have been proposed, it remains unknown whether a specific molecular signaling pathway within CA1 mediates context learning associated with morphine conditioning. Here, we showed that repeated context learning associated with morphine conditioning significantly increased CXCL12 levels in hippocampal CA1 neurons, and the inhibition of CXCL12 expression ameliorated the CPP behavior following context exposure with morphine conditioning. Additionally, repeated context exposure with morphine conditioning increased the phosphorylation of STAT3 and the acetylation of histone H4 in CXCL12-expressing neurons in CA1. Immunoprecipitation and chromatin immunoprecipitation assays demonstrated that repeated context exposure with morphine conditioning increased the binding of STAT3 to the CXCL12 gene promoter and the interaction between STAT3 and p300, which contributed to the enhanced transcription of CXCL12 by increasing the acetylation of histone H4 in the CXCL12 gene promoter. The inhibition of STAT3 by intrathecal injection of S3I-201 suppressed the acetylation of histone H4. These data demonstrated the epigenetic upregulation of CXCL12 following repeated context exposure with morphine conditioning, which potentially contributed to the spatial memory consolidation associated with conditioned place preference induced by morphine conditioning.
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Quimiocina CXCL12/genética , Condicionamiento Psicológico , Epigénesis Genética , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Morfina/farmacología , Memoria Espacial/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Animales , Quimiocina CXCL12/biosíntesis , Quimiocina CXCL12/metabolismo , Masculino , Narcóticos/farmacología , Ratas , Ratas Sprague-DawleyRESUMEN
A large number of symmetry-protected topological (SPT) phases have been hypothesized for strongly interacting spin-1/2 systems in one dimension. Realizing these SPT phases, however, often demands fine-tunings hard to reach experimentally. And the lack of analytical solutions hinders the understanding of their many-body wave functions. Here we show that two kinds of SPT phases naturally arise for ultracold polar molecules confined in a zigzag optical lattice. This system, motivated by recent experiments, is described by a spin model whose exchange couplings can be tuned by an external field to reach parameter regions not studied before for spin chains or ladders. Within the enlarged parameter space, we find the ground state wave function can be obtained exactly along a line and at a special point, for these two phases, respectively. These exact solutions provide a clear physical picture for the SPT phases and their edge excitations. We further obtain the phase diagram by using infinite time-evolving block decimation and discuss the phase transitions between the two SPT phases and their experimental signatures.
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Lung adenocarcinoma (LUAD) is the most frequent pathological type of lung cancer that has a poor prognosis and high mortality rate. DNA methylation plays a critical role in various biological processes during development, while dysregulation results in pathological consequences. Thus, this study aimed to identify DNA methylation-regulated genes involved in LUAD occurrence. Initially, 300 downregulated and 168 upregulated mRNA expression levels were identified in two databases: Gene Expression Omnibus (GEO) and The Cancer Genome Atlas. In addition, GEO was utilized to detect 243 DNA hyper-methylated sites. Based on our observations, it was possible to correlate downregulation of mRNA expression and DNA hyper-methylation of six genes (ABCA3, COX7A1, HOXA5, SLIT3, SOX17, and SPARCL1). Functional analysis of the six genes indicated that these genes are predominantly enriched in cancer-related pathways and may promote carcinogenesis by regulating epithelialmesenchymal transition processes. In conclusion, our study identified a panel of DNA methylation-regulated genes involved in LUAD and may serve as potential epigenetic markers for this type of carcinoma.
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Adenocarcinoma del Pulmón/genética , Metilación de ADN/genética , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias Pulmonares/genética , Perfilación de la Expresión Génica , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Análisis por Matrices de ProteínasRESUMEN
Asprellosides A-K, nine new ursane-type triterpenoid glycosides (1-9), and two new oleanane-type triterpenoid glycosides (10 and 11), including six rare sulfated triterpenoid glycosides, were isolated from the roots of Ilex asprella. Their structures were determined on the basis of comprehensive spectroscopic analysis and chemical methods. Among these compounds, asprelloside B (2) and asprelloside C (3) are the first examples of triterpenoid glycosides bearing a rare 3,4-O-disulfo-xylopyranosyl residue. All the saponins isolated showed no significant effects against respiratory syncytial virus (RSV) and lipopolysaccharide-induced nitric oxide production in Raw264.7 macrophages.
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Antivirales/farmacología , Glicósidos/farmacología , Ilex/química , Óxido Nítrico/antagonistas & inhibidores , Virus Sincitiales Respiratorios/efectos de los fármacos , Triterpenos/farmacología , Animales , Antivirales/química , Antivirales/aislamiento & purificación , Glicósidos/química , Glicósidos/aislamiento & purificación , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Óxido Nítrico/biosíntesis , Raíces de Plantas/química , Células RAW 264.7 , Triterpenos/química , Triterpenos/aislamiento & purificaciónRESUMEN
We experimentally investigate the quantum criticality and Tomonaga-Luttinger liquid (TLL) behavior within one-dimensional (1D) ultracold atomic gases. Based on the measured density profiles at different temperatures, the universal scaling laws of thermodynamic quantities are observed. The quantum critical regime and the relevant crossover temperatures are determined through the double-peak structure of the specific heat. In the TLL regime, we obtain the Luttinger parameter by probing sound propagation. Furthermore, a characteristic power-law behavior emerges in the measured momentum distributions of the 1D ultracold gas, confirming the existence of the TLL.
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A new δ-oleanane-type triterpenoid glycoside, 3-O-(3-O-sulfo)-ß-D-glucopyranosiduronic acid 3ß-hydroxy-13(18)-oleanen- 28-oic acid 28-ß-D-glucopyranosyl ester (1), along with ten known triterpenoid glycosides, rotundinoside A (2), oblonganoside M (3), 3-O-ß-D-glucopyranosyl-(1â2)-α-L-arabinopyranosyl 3ß,19α-dihydroxy-20α- urs-12-en-28-oic acid 28-O-ß-D- glucopyranosyl ester (4), ilexsaponin B2 (5), ilexside â ¡ (6), rotundinoside B (7), ilekudinoside B (8), ilexpublesnin E (9), ilekudinoside D (10) and ilexpernoside D (11), was isolated from the 75% ethanol extract of the roots of Ilex asprella by various chromatographic separation. Their structures were identified on the basis of MS, NMR spectroscopic analysis and chemical methods. In addition, 2-11 were isolated from I. asprella for the first time.
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Ilex/química , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/aislamiento & purificación , Raíces de Plantas/química , Glicósidos , Estructura MolecularRESUMEN
A new flavonoid glycoside, (-)-2S-8-methyl-5,7,4'-trihydroxyflavanone-7-O-ß-D-glucopyranoside (1), along with five known ones, quercetin-3-O-(2"-galloyl)-α-L-arabinoside (2), kaempferol-3-O-α-L-arabinoside (3), guaijaverin (4), trifolin (5) and hyperin (6), was isolated from the leaves of Eucalyptus robusta. Their structures with absolute configurations were elucidated by NMR, HR-ESI-MS, CD spectra data and physicochemical methods. In addition, 2-6 were isolated from E. robusta for the first time.
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Eucalyptus/química , Flavonoides/aislamiento & purificación , Glicósidos/aislamiento & purificación , Flavonoides/química , Glicósidos/química , Hojas de la Planta/químicaRESUMEN
RATIONALE: Aggressive vertebral hemangiomas (AVHs) destroy continuous vertebral bodies and intervertebral discs and resulting in spinal kyphosis is extremely rare. The very aggressive behavior was attributable to its significant vascular component and contained no adipose tissue. PATIENT CONCERNS: We report a case of thoracic spine kyphosis of AVHs with multiple vertebral bodies and intervertebral disc destruction in a 45-year-old woman. DIAGNOSES: Based on the imaging studies, the patient underwent surgical removal of this lesion and spinal reconstruction. Histopathology consistent with vertebral hemangioma and contained no adipose. INTERVENTIONS: The patient underwent surgical removal of the lesion and spinal reconstruction. After subperiosteal dissection of the paraspinal muscles and exposure of the laminae, the laminae of the T5-7 vertebrae were removed and exposing the lesion. The lesion was soft and showed cystic changes, completely curetted and autogenous bone was implanted. Vertebroplasty was performed through T3-T9 pedicles bilaterally. Pedicle screw fixation was performed for segmental fixation and fusion. OUTCOMES: After 9 days of operation, the incision healed cleanly and free of pain. She was discharged in good general condition. The patient remained asymptomatic after follow-up 6 months of postoperative. LESSONS: AVHs destroy multiple vertebral bodies and intervertebral discs and resulting in spinal kyphosis is extremely rare.
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Hemangioma , Cifosis , Tornillos Pediculares , Fracturas de la Columna Vertebral , Femenino , Humanos , Persona de Mediana Edad , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Cifosis/etiología , Cifosis/cirugía , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía , Vértebras Torácicas/lesiones , Hemangioma/complicaciones , Hemangioma/cirugía , Hemangioma/patología , Resultado del Tratamiento , Fracturas de la Columna Vertebral/cirugíaRESUMEN
In this study, we successfully synthesize cationic/neutral/anionic inverse-Hofmann-type spin crossover (SCO) frameworks with 1,1,2,2-tetrakis(4-(pyridine-4-yl)phenyl)-ethene ligand by means of cyanometallic charge engineering strategy. The cationic and neutral frameworks exhibit single-step thermally induced spin transition behaviors, while the SCO capability of anionic framework can be aroused by partial desolvation. This strategy provides a new idea to construct ionic SCO frameworks and extends the toolkit for SCO materials.
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BACKGROUND: The Ozaki technique demonstrated promising results in adults, but few studies reported on pediatric patients with limited follow-up time. This study aimed to evaluate the mid-term results of Ozaki technique compared with Ross operation for complex aortic valve (AV) diseases in children. MATERIALS AND METHODS: One hundred and seventeen children underwent either Ozaki (n = 64) or Ross (n = 53) operation from January 2017 to December 2023. The primary endpoint was incidence of moderate or severe regurgitation/stenosis (AR/AS) post procedure. RESULTS: No significant difference was observed in age (6.5±3.4 vs. 7.9±4.3 years) and weight (25.9±15.5 vs. 31.0±25.9 kgs) at surgery. The Ozaki group had significantly more patients in heart failure (20.3% vs. 1.9%, P = 0.003) before surgery and more patients needed ECMO installation (6.3% vs. 0, P = 0.125) after surgery. The Ozaki group were in worse status with more patients occurred heart failure (20.3% vs. 1.9%, P = 0.003) before surgery and needed ECMO installation (6.3% vs. 0, P = 0.125) after surgery. During follow up (20.4±17.3 vs. 22.7±22.8 months, P = 0.526), five patients (7.8%) in Ozaki group but no patients in Ross group required reoperations. The incidence of moderate or severe AR (28.1% vs. 3.1%) and AS (31.3% vs. 5.7%) were significantly higher than Ross group. Multivariate analysis identified lower age [HR:1.282 (95%CI:1.075-1.529), P = 0.006] and ECMO installation [HR:0.126 (0.018-0.887), P = 0.037] to be risk factors for moderate or severe AR, and higher aortic transvalvular gradient before discharge was confirmed as the only risk factor for moderate or severe AS (≥36 mmHg) at follow up in Ozaki group. CONCLUSION: Ozaki technique may be used as a palliative procedure for complex AV diseases in children, but its' mid-term results were not durable as Ross surgery, especially younger patients.