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1.
Cell Rep ; 43(4): 114054, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38578832

RESUMO

Cell fate conversion is associated with extensive post-translational modifications (PTMs) and architectural changes of sub-organelles, yet how these events are interconnected remains unknown. We report here the identification of a phosphorylation code in 14-3-3 binding motifs (PC14-3-3) that greatly stimulates induced cardiomyocyte (iCM) formation from fibroblasts. PC14-3-3 is identified in pivotal functional proteins for iCM reprogramming, including transcription factors and chromatin modifiers. Akt1 kinase and protein phosphatase 2A are the key writer and key eraser of the PC14-3-3 code, respectively. PC14-3-3 activation induces iCM formation with the presence of only Tbx5. In contrast, PC14-3-3 inhibition by mutagenesis or inhibitor-mediated code removal abolishes reprogramming. We discover that key PC14-3-3-embedded factors, such as histone deacetylase 4 (Hdac4), Mef2c, and Foxo1, form Hdac4-organized inhibitory nuclear condensates. PC14-3-3 activation disrupts Hdac4 condensates to promote cardiac gene expression. Our study suggests that sub-organelle dynamics regulated by a PTM code could be a general mechanism for stimulating cell reprogramming.


Assuntos
Proteínas 14-3-3 , Reprogramação Celular , Histona Desacetilases , Miócitos Cardíacos , Proteínas 14-3-3/metabolismo , Histona Desacetilases/metabolismo , Fosforilação , Animais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Camundongos , Humanos , Fibroblastos/metabolismo , Fatores de Transcrição MEF2/metabolismo , Motivos de Aminoácidos , Ligação Proteica
2.
Colloids Surf B Biointerfaces ; 237: 113838, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38484445

RESUMO

The emergence of nanotechnology has opened up a new way for tumor therapy. Among them, self-assembled nanotechnology has received extensive attention in medicine due to its simple preparation process, high drug-loading capacity, low toxicity, and low cost. This review mainly summarizes the preparation methods of self-assembled nano-delivery systems, as well as the self-assembled mechanism of carrier-free nanomedicine, polymer-carried nanomedicine, polypeptide, and metal drugs, and their applications in tumor therapy. In addition, we discuss the advantages and disadvantages, future challenges, and opportunities of these self-assembled nanomedicines, which provide important references for the development and application of self-assembled nanotechnology in the field of medical therapy.


Assuntos
Sistemas de Liberação de Medicamentos , Neoplasias , Humanos , Nanotecnologia , Nanomedicina , Peptídeos/uso terapêutico , Neoplasias/tratamento farmacológico
3.
Heliyon ; 10(1): e23223, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38148798

RESUMO

Macrophages play a crucial role in regulating inflammation and innate immune responses, and their polarization into distinct phenotypes, such as M1 and M2, is involved in various diseases. However, the specific role of CD163, a scavenger receptor expressed by macrophages, in the transformation of M2 to M1 macrophages remains unclear. Here, dexamethasone-induced M2 macrophages were treated with lipopolysaccharide (LPS) to induce the transformation of M2 to M1 macrophages. We found that treatment with lipopolysaccharide (LPS) induced the transformation of M2-like macrophages to an M1-like phenotype, as evidenced by increased mRNA levels of Il1b and Tnf, decreased mRNA levels of Cd206 and Il10, and increased TNF-α secretion. Knockdown of CD163 enhanced the phenotypic features of M1 macrophages, while treatment with recombinant CD163 protein (rmCD163) inhibited the LPS-induced M2-to-M1 transformation. Furthermore, LPS stimulation resulted in the activation of P38, ERK, JNK, and NF-κB P65 signaling pathways, and this activation was increased after CD163 knockdown and suppressed after rmCD163 treatment during macrophage transformation. Additionally, we observed that LPS treatment reduced the expression of CD163 in dexamethasone-induced M2 macrophages, leading to a decrease in the CD163-TWEAK complex and an increase in the interaction between TWEAK and Fn14. Overall, our findings suggest that rmCD163 can inhibit the LPS-induced transformation of M2 macrophages to M1 by disrupting the TWEAK-Fn14 interaction and modulating the MAPK-NF-κB pathway.

4.
bioRxiv ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38045244

RESUMO

Cell fate conversion is associated with extensive epigenetic and post translational modifications (PTMs) and architectural changes of sub-organelles and organelles, yet how these events are interconnected remains unknown. We report here the identification of a phosphorylation code in 14-3-3 binding motifs (PC14-3-3) that greatly stimulates induced cardiomyocyte (iCM) formation from fibroblasts. PC14-3-3 was identified in pivotal functional proteins for iCM reprogramming, including transcription factors and epigenetic factors. Akt1 kinase and PP2A phosphatase were a key writer and eraser of the PC14-3-3 code, respectively. PC14-3-3 activation induces iCM formation with the presence of only Tbx5. In contrast, PC14-3-3 inhibition by mutagenesis or inhibitor-mediated code removal abolished reprogramming. We discovered that key PC14-3-3 embedded factors, such as Hdac4, Mef2c, Nrip1, and Foxo1, formed Hdac4 organized inhibitory nuclear condensates. Notably, PC14-3-3 activation disrupted Hdac4 condensates to promote cardiac gene expression. Our study suggests that sub-organelle dynamics regulated by a post-translational modification code could be a general mechanism for stimulating cell reprogramming and organ regeneration. Highlights: A PC14-3-3 (phosphorylation code in 14-3-3 binding motifs) is identified in pivotal functional proteins, such as HDAC4 and Mef2c, that stimulates iCM formation.Akt1 kinase and PP2A phosphatase are a key writer and a key eraser of the PC14-3-3 code, respectively, and PC14-3-3 code activation can replace Mef2c and Gata4 in cardiac reprogramming.PC14-3-3 activation disrupts Hdac4 organized condensates which results in releasing multiple 14-3-3 motif embedded proteins from the condensates to stimulate cardiac reprogramming.Sub-organelle dynamics and function regulated by a post-translational modification code could be a general mechanism in stimulating cell reprogramming and organ regeneration.

5.
Front Cardiovasc Med ; 10: 1123385, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324634

RESUMO

A number of vaccines have been developed and deployed globally to restrain the spreading of the coronavirus disease 2019 (COVID-19). The adverse effect following vaccination is an important consideration. Acute myocardial infarction (AMI) is a kind of rare adverse event after COVID-19 vaccination. Herein, we present a case of an 83-year-old male who suffered cold sweat ten minutes after the first inactivated COVID-19 vaccination and AMI one day later. The emergency coronary angiography showed coronary thrombosis and underlying stenosis in his coronary artery. Type II Kounis syndrome might be a potential mechanism, which is manifested as coronary thrombosis secondary to allergic reactions in patients with underlying asymptomatic coronary heart disease. We also summarize the reported AMI cases post COVID-19 vaccination, as well as overview and discuss the proposed mechanisms of AMI after COVID-19 vaccination, thus providing insights for clinicians to be aware of the possibility of AMI following COVID-19 vaccination and potential underlying mechanisms.

6.
Heliyon ; 9(5): e16318, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37251884

RESUMO

The phosphorylation of 14-3-3 binding motif is involved in many cellular processes. A strategy that enables targeted degradation of 14-3-3-binding phosphoproteins (14-3-3-BPPs) for studying their functions is highly desirable for basic research. Here, we report a phosphorylation-induced, ubiquitin-proteasome-system-mediated targeted protein degradation (TPD) strategy that allows specific degradation of 14-3-3-BPPs. Specifically, by ligating a modified von Hippel-Lindau E3-ligase with an engineered 14-3-3 bait, we generated a protein chimera referred to as Targeted Degradation of 14-3-3-binding PhosphoProtein (TDPP). TDPP can serve as a universal degrader for 14-3-3-BPPs based on the specific recognition of the phosphorylation in 14-3-3 binding motifs. TDPP shows high efficiency and specificity to a difopein-EGFP reporter, general and specific 14-3-3-BPPs. TDPP can also be applied for the validation of 14-3-3-BPPs. These results strongly support TDPP as a powerful tool for 14-3-3 related research.

7.
Biology (Basel) ; 11(10)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36290302

RESUMO

(1) Background: Galloway-Mowat syndrome (GAMOS) is a rare genetic disease, classically characterized by a combination of various neurological symptoms and nephrotic syndrome. WDR73 is the pathogenic gene responsible for GAMOS1. However, the pathological and molecular mechanisms of GAMOS1, especially nephrotic syndrome caused by WDR73 deficiency, remain unknown. (2) Methods and Results: In this study, we first observed remarkable cellular morphological changes including impaired cell adhesion, decreased pseudopodia, and G2/M phase arrest in WDR73 knockout (KO) HEK 293 cells. The differentially expressed genes in WDR73 KO cells were enriched in the focal adhesion (FA) pathway. Additionally, PIP4K2C, a phospholipid kinase also involved in the FA pathway, was subsequently validated to interact with WDR73 via protein microarray and GST pulldown. WDR73 regulates PIP4K2C protein stability through the autophagy-lysosomal pathway. The stability of PIP4K2C was significantly disrupted by WDR73 KO, leading to a remarkable reduction in PIP2 and thus weakening the FA formation. In addition, we found that podocyte-specific conditional knockout (Wdr73 CKO) mice showed high levels of albuminuria and podocyte foot process injury in the ADR-induced model. FA formation was impaired in primary podocytes derived from Wdr73 CKO mice. (3) Conclusions: Since FA has been well known for its critical roles in maintaining podocyte structures and function, our study indicated that nephrotic syndrome in GAMOS1 is associated with disruption of FA caused by WDR73 deficiency.

8.
Entropy (Basel) ; 24(9)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36141069

RESUMO

In order to solve the problems in fuzzy computation tree logic model checking with cost operator, we propose a fuzzy decision process computation tree logic model checking method with cost. Firstly, we introduce a fuzzy decision process model with cost, which can not only describe the uncertain choice and transition possibility of systems, but also quantitatively describe the cost of the systems. Secondly, under the model of the fuzzy decision process with cost, we give the syntax and semantics of the fuzzy computation tree logic with cost operators. Thirdly, we study the problem of computation tree logic model checking for fuzzy decision process with cost, and give its matrix calculation method and algorithm. We use the example of medical expert systems to illustrate the method and model checking algorithm.

9.
Electrophoresis ; 43(21-22): 2074-2092, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36030405

RESUMO

We introduce herein an effective way for continuous delivery and position-switchable trapping of nanoparticles via field-effect control on hybrid electrokinetics (HEK). Flow field-effect transistor exploiting HEK delicately combines horizontal linear electroosmosis and transversal nonlinear electroosmosis of a shiftable flow stagnation line (FSL) on gate terminals under DC-biased AC forcing. The microfluidic nanoparticle concentrator proposed herein makes use of a simple device geometry, in which an individual or a series of planar metal strips serving as gate electrode (GE) are subjected to a hybrid gate voltage signal and arranged in parallel between a pair of 3D driving electrodes. On the application of a DC-biased AC electric field across channel length direction, all the GE are electrochemically polarized, and the action of imposed hybrid electric field on the multiple-frequency bipolar counterions within the composite-induced double layer generates two counter-rotating induced-charge electroosmotic (ICEO) micro-vortices on top of each GE. Symmetry breaking in ICEO flow profile occurs once the gate voltage deviates from natural floating potential of corresponding GE. The gate voltage offset not only results in an additional pump motion of working fluid for enhanced electroosmotic transport but also directly changes the location of FSL where nanoparticles are preferentially collected by field-effect HEK. Our results of field-effect control on HEK are supposed to guide an elaborate design of flexible electrokinetic frameworks embedding coplanar metal strips for a high degree of freedom analyte manipulation in modern micro-total-analytical systems.

10.
Front Cardiovasc Med ; 9: 913437, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35656392

RESUMO

Background: Serum uric acid (SUA) levels was associated with cardiovascular diseases and cardiovascular events. However, the relationship between SUA levels and traditional cardiovascular risk factors has not been well-established among Xiamen residents. Our study aimed to estimate the relationship between SUA levels and cardiovascular risk factors among Xiamen residents using real-world data. Methods: Participants were enrolled from eight community health service centers in Xiamen, China. Participants were divided into four groups according to quartiles of the SUA levels. The history of diseases, the use of medications and the levels of laboratory parameters were collected. The China-PAR equation was used to evaluate the 10-year atherosclerotic cardiovascular disease (ASCVD) risk. Results: A total of 1,322 participants were enrolled. About 568 (43.0%) were men and 754 (57.0%) were women. The prevalences of hypertension, elderly, current smokers, and obesity were higher in the quartile 4 (Q4) group than the quartile 1 (Q1) group (all p < 0.001). Multivariable logistic regression analysis showed the OR for hypertension was 2.671 (95% CI 1.777-4.015, p < 0.001) in the Q4 group compared with that in the Q1 group. Further logistic regression showed the OR for hypertension was 3.254 (95% CI 1.756-6.031, p < 0.001) in men and 2.314 (95% CI 1.354-3.955, p = 0.002) in women in the Q4 group compared with that in the Q1 group, respectively. In addition, the percentage of participants with low 10-year ASCVD risk calculated by China-PAR was higher in the Q1 group than that in the Q4 group (55.86 vs. 31.82%, p < 0.001). The percentage of participants with high 10-year ASCVD risk was lower in the Q1 group compared with the Q4 group (15.32 vs. 25.45%, p < 0.001). Multiple linear logistic regression showed the 10-year China-PAR ASCVD risk scores was positively correlated with SUA after adjusting for various factors (ß = 0.135, p = 0.001). Conclusion: Serum uric acid was associated with several cardiovascular risk factors in Xiamen residents. The percentage of high 10-year ASDVD risk was higher in participants with hyperuricemia. Participants with hyperuricemia may experience cardiovascular benefit from uric acid-lowering therapy.

11.
J Vis Exp ; (180)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35285824

RESUMO

Cardiac reprogramming has become a potentially promising therapy to repair a damaged heart. By introducing multiple transcription factors, including Mef2c, Gata4, Tbx5 (MGT), fibroblasts can be reprogrammed into induced cardiomyocytes (iCMs). These iCMs, when generated in situ in an infarcted heart, integrate electrically and mechanically with the surrounding myocardium, leading to a reduction in scar size and an improvement in heart function. Because of the relatively low reprogramming efficiency, purity, and quality of the iCMs, characterization of iCMs remains a challenge. The currently used methods in this field, including flow cytometry, immunocytochemistry, and qPCR, mainly focus on cardiac-specific gene and protein expression but not on the functional maturation of iCMs. Triggered by action potentials, the opening of voltage-gated calcium channels in cardiomyocytes leads to a rapid influx of calcium into the cell. Therefore, quantifying the rate of calcium influx is a promising method to evaluate cardiomyocyte function. Here, the protocol introduces a method to evaluate iCM function by calcium (Ca2+) flux. An αMHC-Cre/Rosa26A-Flox-Stop-Flox-GCaMP3 mouse strain was established by crossing Tg(Myh6-cre)1Jmk/J (referred to as Myh6-Cre below) with Gt(ROSA)26Sortm38(CAG-GCaMP3)Hze/J (referred to as Rosa26A-Flox-Stop-Flox-GCaMP3 below) mice. Neonatal cardiac fibroblasts (NCFs) from P0-P2 neonatal mice were isolated and cultured in vitro, and a polycistronic construction of MGT was introduced to NCFs, which led to their reprogramming to iCMs. Because only successfully reprogrammed iCMs will express GCaMP3 reporter, the functional maturation of iCMs can be visually assessed by Ca2+ flux with fluorescence microscopy. Compared with un-reprogrammed NCFs, NCF-iCMs showed significant calcium transient flux and spontaneous contraction, similar to CMs. This protocol describes in detail the mouse strain establishment, isolation and selection of neonatal mice hearts, NCF isolation, production of retrovirus for cardiac reprogramming, iCM induction, the evaluation of iCM Ca2+ flux using our reporter line, and related statistical analysis and data presentation. It is expected that the methods described here will provide a valuable platform to assess the functional maturation of iCMs for cardiac reprogramming studies.


Assuntos
Cálcio , Reprogramação Celular , Animais , Cálcio/metabolismo , Fibroblastos/metabolismo , Camundongos , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo
12.
Front Cardiovasc Med ; 9: 991521, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36704464

RESUMO

Background: Cardiac rehabilitation (CR) is an essential intervention after acute myocardial infarction (MI). However, it is still unclear whether patients with left ventricular aneurysm (LVA) formation after anterior MI would benefit from CR programs. This clinical trial is designed to assess the role of CR in patients with LVA formation after anterior MI. Trial design: The GRACE study is a single-center, single-blind, prospective, randomized controlled clinical trial in China. 100 subjects aged 18-75 years with LVA formation after anterior MI will be recruited and randomized 1:1 to the CR or control group. Both groups will receive standard drug treatment and routine health education according to the guidelines. Participants in the CR group will additionally receive tailored CR programs delivered over a period of 36 sessions. These participants will then be followed up for 1-year. The primary outcome is peak oxygen uptake measured by cardiopulmonary exercise testing after CR programs. The secondary outcomes are cardiac function and EuroQol 5-Dimension-3 Level index scores after CR program and 1-year and major adverse cardiac cerebrovascular events, a composite of cardiovascular mortality, non-fatal MI, non-fatal stroke, malignant arrhythmia or hospitalization for heart failure during the follow-up period. Conclusions: This single-center, single-blind, prospective, randomized controlled clinical trial will determine whether CR improves physical capacity and clinical outcomes in patients with LVA formation after anterior MI. Trial registration: Chinese Clinical Trial Registry ChiCTR2200058852. Registered on 18 April 2022.

13.
Cells ; 10(12)2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34943805

RESUMO

Direct reprogramming of fibroblasts into CM-like cells has emerged as an attractive strategy to generate induced CMs (iCMs) in heart regeneration. However, low conversion rate, poor purity, and the lack of precise conversion of iCMs are still present as significant challenges. In this review, we summarize the recent development in understanding the molecular mechanisms of cardiac reprogramming with various strategies to achieve more efficient iCMs. reprogramming. Specifically, we focus on the identified critical roles of transcriptional regulation, epigenetic modification, signaling pathways from the cellular microenvironment, and cell cycling regulation in cardiac reprogramming. We also discuss the progress in delivery system optimization and cardiac reprogramming in human cells related to preclinical applications. We anticipate that this will translate cardiac reprogramming-based heart therapy into clinical applications. In addition to optimizing the cardiogenesis related transcriptional regulation and signaling pathways, an important strategy is to modulate the pathological microenvironment associated with heart injury, including inflammation, pro-fibrotic signaling pathways, and the mechanical properties of the damaged myocardium. We are optimistic that cardiac reprogramming will provide a powerful therapy in heart regenerative medicine.


Assuntos
Reprogramação Celular , Coração/fisiologia , Regeneração , Ciência Translacional Biomédica , Animais , Microambiente Celular/genética , Reprogramação Celular/genética , Epigênese Genética , Humanos , Regeneração/genética
14.
Sci Adv ; 7(34)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34407942

RESUMO

Principal component analysis (PCA) has been widely adopted to reduce the dimension of data while preserving the information. The quantum version of PCA (qPCA) can be used to analyze an unknown low-rank density matrix by rapidly revealing the principal components of it, i.e., the eigenvectors of the density matrix with the largest eigenvalues. However, because of the substantial resource requirement, its experimental implementation remains challenging. Here, we develop a resonant analysis algorithm with minimal resource for ancillary qubits, in which only one frequency-scanning probe qubit is required to extract the principal components. In the experiment, we demonstrate the distillation of the first principal component of a 4 × 4 density matrix, with an efficiency of 86.0% and a fidelity of 0.90. This work shows the speedup ability of quantum algorithm in dimension reduction of data and thus could be used as part of quantum artificial intelligence algorithms in the future.

15.
Sci Bull (Beijing) ; 66(1): 23-28, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36654308

RESUMO

An important task for quantum cloud computing is to make sure that there is a real quantum computer running, instead of classical simulation. Here we explore the applicability of a cryptographic verification scheme for verifying quantum cloud computing. We provided a theoretical extension and implemented the scheme on a 5-qubit NMR quantum processor in the laboratory and a 5-qubit and 16-qubit processors of the IBM quantum cloud. We found that the experimental results of the NMR processor can be verified by the scheme with about 1.4% error, after noise compensation by standard techniques. However, the fidelity of the IBM quantum cloud is currently too low to pass the test (about 42% error). This verification scheme shall become practical when servers claim to offer quantum-computing resources that can achieve quantum supremacy.

16.
Clin Oral Implants Res ; 30(12): 1190-1199, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31506979

RESUMO

OBJECTIVES: To evaluate the peri-implant trabecular bone volume and architecture changes with 6-month follow-up after local application of platelet-rich plasma (PRP) and platelet-poor plasma (PPP) using high-resolution micro-CT. MATERIAL AND METHODS: Seventy-two dental implants were placed into healed mandibular sites of 9 beagle dogs. Implants were randomly divided into 4 groups following a split-mouth design: control I; control II; PPP; and PRP. Primary and secondary stabilities were assessed using resonance frequency analyses. At 1, 3, and 6 months after implant loading, trabecular structural parameters were evaluated at 0.5, 1, and 1.5 mm away from implants using micro-CT (voxel = 20 µm). RESULTS: Primary and secondary stabilities were equivalent in all conditions. PPP and PRP groups showed higher bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) but lower trabecular separation (Tb.Sp) and total porosity percentage (Po (tot)) at all 3 time points. A significant decrease in BV/TV and Tb.Th was found for the control groups after 3 months of healing, while this was not observed in both the PPP and PRP groups. However, no distinct difference was found between the PRP and PPP groups over time. Moreover, as the investigated distance from the implant surface increased, BV/TV and Po (tot) within the same group and time point stayed the same, yet Tb.Th and Tb.Sp continued to increase. CONCLUSIONS: Platelet-rich plasma and PPP with conventional implant placement lead to similar primary and secondary implant stability, but improved peri-implant bone volume and structural integration. The present research does not seem to suggest a different bone remodeling pattern when using PRP or PPP.


Assuntos
Implantes Dentários , Plasma Rico em Plaquetas , Animais , Cães , Mandíbula , Cicatrização , Microtomografia por Raio-X
17.
Phys Rev Lett ; 122(9): 090504, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932514

RESUMO

It is difficult to calculate the energy levels and eigenstates of a large physical system on a classical computer because of the exponentially growing size of the Hilbert space. In this work, we experimentally demonstrate a quantum algorithm which could solve this problem via simulated resonant transitions. Using a four-qubit quantum simulator in which two qubits are used as ancillas for control and measurement, we obtain the energy spectrum of a 2-qubit low-energy effective Hamiltonian of the water molecule. The simulated transitions allow the state of the quantum simulator to transform and access large regions of the Hilbert space, including states that have no overlap with the initial state. Furthermore, we make use of this algorithm to efficiently prepare specific eigenstates on the simulator according to the measured eigenenergies.

18.
Sci Bull (Beijing) ; 64(13): 888-895, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36659752

RESUMO

Quantum state transfer between two distant parties is at the heart of quantum computation and quantum communication. Among the various protocols, the counterdiabatic driving (CD) method, by suppressing the unwanted transitions with an auxiliary Hamiltonian Hcd(t), offers a fast and robust strategy to transfer quantum states. However, Hcd(t) term often takes a complicated form in higher-dimensional systems and is difficult to realize in experiment. Recently, the Floquet-engineered method was proposed to emulate the dynamics induced by Hcd(t) without the need for complex interactions in multi-qubit systems, which can accelerate the adiabatic process through the fast-oscillating control in the original Hamiltonian H0(t). Here, we apply this method in the Heisenberg spin chains, with only control of the two marginal couplings, to achieve the fast, high-fidelity, and robust quantum state transfer. Then we report an experimental implementation of our scheme using a nuclear magnetic resonance simulator. The experimental results demonstrate the feasibility of this method in complex many-body system and thus provide a new alternative to realize the high-fidelity quantum state manipulation in practice.

19.
Sci Bull (Beijing) ; 63(8): 469-476, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36658807

RESUMO

Nonlinear quantum metrology may exhibit better precision scalings. For example, the uncertainty of an estimated phase may scale as Δϕ∝1/N2 under quadratic phase accumulation, which is 1/N times smaller than the linear counterpart, where N is probe number. Here, we experimentally demonstrate the nonlinear quantum metrology by using a spin-I (I>1/2) nuclear magnetic resonance (NMR) ensemble that can be mapped into a system of N=2I spin-1/2 particles and the quadratic interaction can be utilized for the quadratic phase accumulation. Our experimental results show that the phase uncertainty can scale as Δϕ∝1/(N2-1) by optimizing the input states, when N is an odd number. In addition, the interferometric measurement with quadratic interaction provides a new way for estimating the quadrupolar coupling strength in an NMR system. Our system may be further extended to exotic nonlinear quantum metrology with higher order many-body interactions.

20.
J Craniomaxillofac Surg ; 45(8): 1287-1292, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28684075

RESUMO

PURPOSE: The soft-tissue pogonion closely follows changes of the bony pogonion, but it is unknown how often an augmented bony pogonion reaches the intended position. Here we assessed the agreement between planned surgical changes and achieved results in chin surgery. MATERIALS AND METHODS: Surgical treatment was planned based on clinical examination, cast model analysis, and cephalometric image analysis. The mobile chin segment was stabilized using one chin plate. Preoperative and postoperative cephalometric X-ray images were digitized, and cephalometric tracing was performed. We calculated and analyzed the changes between the preoperative and postoperative images as well as between planned genioplasty movements and actual surgical changes in the horizontal and vertical directions. RESULTS: This study included 36 patients. In 34 patients, the absolute mean horizontal difference was less than 2 mm. We found a higher range of absolute error in vertical (0.00-5.60) compared to horizontal (0.01-3.64) movement. There was no significant difference between the mean planned chin movement and the mean achieved position with regard to the horizontal and vertical movement (p = 0.97 and 0.79, respectively). CONCLUSIONS: The mean values for linear difference in both the horizontal and vertical directions were in line with the acceptable mean of ≤2 mm proposed in the literature.


Assuntos
Queixo/anatomia & histologia , Queixo/cirurgia , Mentoplastia , Adolescente , Adulto , Cefalometria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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