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1.
Proc Natl Acad Sci U S A ; 120(50): e2312224120, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38051768

RESUMO

To master the activation law and mechanism of surface lattice oxygen for the oxygen evolution reaction (OER) is critical for the development of efficient water electrolysis. Herein, we propose a strategy for triggering lattice-oxygen oxidation and enabling non-concerted proton-electron transfers during OER conditions by substituting Al in La0.3Sr0.7CoO3-δ. According to our experimental data and density functional theory calculations, the substitution of Al can have a dual effect of promoting surface reconstruction into active Co oxyhydroxides and activating deprotonation on the reconstructed oxyhydroxide, inducing negatively charged oxygen as an active site. This leads to a significant improvement in the OER activity. Additionally, Al dopants facilitate the preoxidation of active cobalt metal, which introduces great structural flexibility due to elevated O 2p levels. As OER progresses, the accumulation of oxygen vacancies and lattice-oxygen oxidation on the catalyst surface leads to the termination of Al3+ leaching, thereby preventing further reconstruction. We have demonstrated a promising approach to achieving tunable electrochemical reconstruction by optimizing the electronic structure and gained a fundamental understanding of the activation mechanism of surface oxygen sites.

2.
BMC Musculoskelet Disord ; 24(1): 583, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37460932

RESUMO

PURPOSE: Humeral shaft fractures (HSFs) can be treated non-operatively (Non-OP), with open reduction and plate osteosynthesis (ORPO), minimally invasive plate osteosynthesis (MIPO), or with intramedullary nails (IMN). However, the best treatment for HSFs still remains controversial.We performed a network meta-analysis to explore which should be the best method for HSFs. METHODS: The computerized search had been conducted on electronic databases PubMed, EMBASE, Cochrane Library, and Medline from the establishment of the database to the end of December 2022. The quality evaluation of the included literature had been completed by Review Manager (version 5.4.1). Stata 17.0 software (Stata Corporation, College Station, Texas, USA)was used for network meta-analysis.We included randomized controlled trials (RCTs) comparing different treatments to treating HSFs. RESULTS: The pairwise comparison results demonstrated that there was no statistical difference between IMN, MIPO, Non-OP, and ORPO in terms of radial nerve injury and infection, and Non-OP presented significantly more nonunion than ORPO, IMN, and MIPO. However, no statistically significant difference between ORPO, IMN, and MIPO was discovered. The results of the network meta-analysis displayed that surface under the cumulative ranking curve (SUCRA) probabilities of IMN, MIPO, Non-OP, and ORPO in radial nerve injury were 46.5%, 66.9%, 77.3%, and 9.3%, respectively, in contrast, that in infection were 68.6%, 53.3%, 62.4%, and 15.4%, respectively, and that in nonunion were 51.7%, 93.1%, 0.7%, and 54.5%, respectively. CONCLUSION: We came to the conclusion that MIPO is currently the most effective way to treat HSFs. TRIAL REGISTRATION: Name of the registry: Prospero, 2. Unique Identifying number or registration ID: CRD42023411293.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Úmero , Humanos , Metanálise em Rede , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fixação Interna de Fraturas/métodos , Fixação Intramedular de Fraturas/métodos , Fraturas do Úmero/cirurgia , Placas Ósseas , Úmero , Resultado do Tratamento
3.
Int J Mol Sci ; 23(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36361524

RESUMO

Hyperphosphorylation and aggregation of the microtubule binding protein tau is a neuropathological hallmark of Alzheimer's disease/tauopathies. Tau neurotoxicity provokes alterations in brain-derived neurotrophic factor (BDNF)/tropomycin receptor kinase B (TRKB)/cAMP-response-element binding protein (CREB) signaling to contribute to neurodegeneration. Compounds activating TRKB may therefore provide beneficial effects in tauopathies. LM-031, a coumarin derivative, has demonstrated the potential to improve BDNF signaling in neuronal cells expressing pro-aggregated ΔK280 tau mutant. In this study, we investigated if LM-031 analogous compounds provide neuroprotection effects through interaction with TRKB in SH-SY5Y cells expressing ΔK280 tauRD-DsRed folding reporter. All four LMDS compounds reduced tau aggregation and reactive oxygen species. Among them, LMDS-1 and -2 reduced caspase-1, caspase-6 and caspase-3 activities and promoted neurite outgrowth, and the effect was significantly reversed by knockdown of TRKB. Treatment of ERK inhibitor U0126 or PI3K inhibitor wortmannin decreased p-CREB, BDNF and BCL2 in these cells, implying that the neuroprotective effects of LMDS-1/2 are via activating TRKB downstream ERK, PI3K-AKT and CREB signaling. Furthermore, LMDS-1/2 demonstrated their ability to quench the intrinsic fluorescence of tryptophan residues within the extracellular domain of TRKB, thereby consolidating their interaction with TRKB. Our results suggest that LMDS-1/2 exert neuroprotection through activating TRKB signaling, and shed light on their potential application in therapeutics of Alzheimer's disease/tauopathies.


Assuntos
Doença de Alzheimer , Neuroblastoma , Fármacos Neuroprotetores , Tauopatias , Humanos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas tau/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Neuroproteção , Doença de Alzheimer/tratamento farmacológico , Cumarínicos/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Neuroblastoma/metabolismo , Receptor trkB/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Caspases
4.
Phys Rev Lett ; 123(1): 016601, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31386403

RESUMO

An explicit spatial localization of a hole is shown in a two-leg t-J ladder in the presence of a staggered chemical potential, which still retains translational symmetry, by the density matrix renormalization group method. Delocalization can be recovered in the following cases, where either the hidden phase string effect is turned off or a finite next-nearest-neighbor hopping t^{'} is added to sufficiently weaken the phase string effect. In addition, two holes are always delocalized by forming a mobile bound pair, in contrast to the localized single holes, which points to a novel pairing mechanism as one of the essential properties of a doped Mott insulator.

5.
Adv Mater ; 36(13): e2311102, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38100677

RESUMO

The electronic structure and geometric configuration of catalysts play a crucial role to design novel perovskite-type catalysts for oxygen reduction reaction (ORR). Nowadays, many studies are more concerned with the influence of electronic structure and ignore the geometric effect, which plays a nonnegligible role in enhancing catalytic performances. Herein, this work regulates the MnO6 octahedral tilting degree of LaMnO3 by modulating the concentration of Y3+, excluding the electronic effect from the valence state of manganese. Plotting the MnO6 octahedral tilting degree as a function of concentration of Y3+ produces a volcano-shaped plot. The octahedral tilting can reduce the Mn-O covalency, generating more highly active Mn3+ and oxygen vacancies during ORR process. The specific activity has a positive correlation with octahedral tilting degree. Meanwhile, the octahedral tilting stabilizes Mn-O interactions during ORR process and promote stability. Based on experimental results and DFT calculations, octahedral tilting alters the rate-determining step (RDS) and decrease the energy barrier. Subsequent extended experiment confirms that octahedral tilting is the key factor to affect the catalytic performances.

6.
Aging (Albany NY) ; 15(20): 11489-11507, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37870753

RESUMO

Osteosarcoma (OS) is a multifactorial bone malignancy that accounts for most cancers in children and adolescents. Formononetin has been proven to exhibit various pharmacological effects including anti-tumor, anti-obesity, anti-inflammation, and neuroprotective effects. Few studies have examined the pharmacological activities of formononetin in OS treatment, but the mechanism has not yet been completely elucidated. Network pharmacology is a new method based on the theory of system biology for analyzing the network of biological systems and selecting specific signal nodes for multi-target drug molecular design. Here, we used network pharmacology to explore the possible mechanism of formononetin in OS treatment. Human OS cell line MG63 was processed with four concentrations (0, 2, 5, 8 µg/mL) of formononetin. Subsequently, an MTT assay was performed to test cell proliferation and a scratch test was used to evaluate the migration ability of cancer cells. Caspase-3, p53, p21, and bcl-2 expression levels incubated with different concentrations of formononetin in MG63 cells were determined using Western blotting. After treated with formononetin for 48 h, MG63 cells exhibited marked apoptosis. The results revealed that certain concentrations of formononetin significantly exerted inhibitory effects on MG63 cell proliferation. Furthermore, formononetin decreased the bcl-2 level in MG63 cells but increased caspase-3, p21, and p53 levels in a concentration-dependent manner. Additionally, formononetin suppressed the expression of SATB2. Therefore, formononetin could dose-dependently inhibit MG63 cell proliferation and induce apparent cell apoptosis, providing a candidate treatment for OS, whereas SATB2 could be a potential prognostic biomarker for screening OS and therapeutic target of formononetin.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Adolescente , Caspase 3/metabolismo , Proteína Supressora de Tumor p53 , Farmacologia em Rede , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
7.
ACS Appl Mater Interfaces ; 15(29): 34852-34861, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37459587

RESUMO

The high specific capacity and relatively low volume expansion of silicon suboxide (SiOx) highlight its potential as one of the most promising anode materials for lithium-ion batteries. Nevertheless, the traditional binder of polyacrylic acid (PAA) still cannot adapt to enormous stress during the repeated volume expansion/contraction owing to its intrinsic rigid backbone. Inspired by the "soft and hard composite body armor", we herein design a double-wrapped binder consisting of PAA with a high internal Young's modulus (hard part) and polyurethane (DOU) with a low external Young's modulus (soft part). When the SiOx particle expands during lithiation, the rigid PAA firstly accommodates the volume change to dissipate most of the inner stress, and the elastic DOU with triple dynamic bonds serves as a buffer layer to absorb the residual stress via the breakage/formation of dynamic bonds. By optimizing the PAA/DOU ratio, the SiOx anode can maintain the integrity during long-term cycling and deliver a relatively high reversible capacity of 1064.1 mAh g-1 with a preeminent capacity retention of 83.7% at 0.5C after 300 cycles. Such a double-wrapped binder can provide a novel design strategy for multicomponent functional polymer binders toward high-performance SiOx anodes.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36762457

RESUMO

Li metal is the ultimate anode material for next-generation high-energy-density rechargeable batteries. However, the uncontrollable growth of Li dendrites and low Coulombic efficiency (CE) prevent it from practical applications in Li metal batteries (LMBs). Here, a facile and low-cost strategy is developed to decorate a Cu current collector with a self-assembled γ-aminopropyltrimethoxysilane (γ-APS) film. The thin polymer film with nanopores promotes the formation of cobblestone-like Li deposition and suppresses Li-dendrite formation due to its low surface energy. The protecting layer not only increases the lithiophilicity of the Cu current collector but also alleviates the ambient corrosion and galvanic corrosion in practical use. Owing to these advantages, the half cell using γ-APS-Cu collectors exhibits a high average CE value of 99.2% for 100 cycles. The symmetric cell of γ-APS-Cu@Li shows an improved lifespan of 1400 h with a small voltage hysteresis of 12 mV at 0.5 mA cm-2. The full cell assembled with LiFePO4 (LFP) cathodes and γ-APS-Cu@Li anodes delivers a high capacity of 136 mAh g-1 after 600 cycles at 0.5C.

9.
Biomolecules ; 13(2)2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36830589

RESUMO

Misfolded aggregation of the hyperphosphorylated microtubule binding protein Tau in the brain is a pathological hallmark of Alzheimer's disease (AD). Tau aggregation downregulates brain-derived neurotrophic factor (BDNF)/tropomycin receptor kinase B (TRKB) signaling and leads to neurotoxicity. Therefore, enhancement of BDNF/TRKB signaling could be a strategy to alleviate Tau neurotoxicity. In this study, eight compounds were evaluated for the potential of inhibiting Tau misfolding in human neuroblastoma SH-SY5Y cells expressing the pro-aggregator Tau folding reporter (ΔK280 TauRD-DsRed). Among them, coumarin derivative ZN-015 and quinoline derivatives VB-030 and VB-037 displayed chemical chaperone activity to reduce ΔK280 TauRD aggregation and promote neurite outgrowth. Studies of TRKB signaling revealed that ZN-015, VB-030 and VB-037 treatments significantly increased phosphorylation of TRKB and downstream Ca2+/calmodulin-dependent protein kinase II (CaMKII), extracellular signal-regulated kinase 1/2 (ERK) and AKT serine/threonine kinase (AKT), to activate ribosomal S6 kinase (RSK) and cAMP response element-binding protein (CREB). Subsequently, p-CREB enhanced the transcription of pro-survival BDNF and BCL2 apoptosis regulator (BCL2), accompanied with reduced expression of anti-survival BCL2-associated X protein (BAX) in ΔK280 TauRD-DsRed-expressing cells. The neurite outgrowth promotion effect of ZN-015, VB-030 and VB-037 was counteracted by a RNA interference-mediated knockdown of TRKB, suggesting the role of these compounds acting as TRKB agonists. Tryptophan fluorescence quenching analysis showed that ZN-015, VB-030 and VB-037 interacted directly with a Pichia pastoris-expressed TRKB extracellular domain, indirectly supporting the role through TRKB signaling. The results of up-regulation in TRKB signaling open up the therapeutic potentials of ZN-015, VB-030 and VB-037 for AD.


Assuntos
Doença de Alzheimer , Neuroblastoma , Humanos , Doença de Alzheimer/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas Proto-Oncogênicas c-akt , Neuroblastoma/metabolismo , Proteínas tau/metabolismo , Receptor trkB/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2
10.
Biomol Ther (Seoul) ; 31(1): 127-138, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35790892

RESUMO

Glycogen synthase kinase-3ß (GSK-3ß) is an important serine/threonine kinase that implicates in multiple cellular processes and links with the neurodegenerative diseases including Alzheimer's disease (AD). In this study, structure-based virtual screening was performed to search database for compounds targeting GSK-3ß from Enamine's screening collection. Of the top-ranked compounds, 7 primary hits underwent a luminescent kinase assay and a cell assay using human neuroblastoma SH-SY5Y cells expressing Tau repeat domain (TauRD) with pro-aggregant mutation ΔK280. In the kinase assay for these 7 compounds, residual GSK-3ß activities ranged from 36.1% to 90.0% were detected at the IC50 of SB-216763. In the cell assay, only compounds VB-030 and VB-037 reduced Tau aggregation in SH-SY5Y cells expressing ΔK280 TauRD-DsRed folding reporter. In SH-SY5Y cells expressing ΔK280 TauRD, neither VB-030 nor VB-037 increased expression of GSK-3α Ser21 or GSK-3ß Ser9. Among extracellular signal-regulated kinase (ERK), AKT serine/threonine kinase 1 (AKT), mitogen-activated protein kinase 14 (P38) and mitogen-activated protein kinase 8 (JNK) which modulate Tau phosphorylation, VB-037 attenuated active phosphorylation of P38 Thr180/Tyr182, whereas VB-030 had no effect on the phosphorylation status of ERK, AKT, P38 or JNK. However, both VB-030 and VB-037 reduced endogenous Tau phosphorylation at Ser202, Thr231, Ser396 and Ser404 in neuronally differentiated SH-SY5Y expressing ΔK280 TauRD. In addition, VB-030 and VB-037 further improved neuronal survival and/or neurite length and branch in mouse hippocampal primary culture under Tau cytotoxicity. Overall, through inhibiting GSK-3ß kinase activity and/or p-P38 (Thr180/Tyr182), both compounds may serve as promising candidates to reduce Tau aggregation/cytotoxicity for AD treatment.

11.
Phys Rev Lett ; 109(3): 037002, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22861886

RESUMO

We report the doping, temperature, and spatial evolutions of the electronic structure of NaFe(1-x)Co(x)As studied by scanning tunneling microscopy. In the parent state we directly observe the spin density wave gap, which exhibits unconventional features that are incompatible with simple Fermi surface nesting. The optimally doped sample has a single superconducting gap, but in the overdoped regime a novel pseudogaplike feature emerges. The pseudogaplike phase coexists with superconductivity in the ground state, persists well into the normal state, and shows strong spatial variations. The characteristics of the three distinct electronic states revealed here shed important new lights on the microscopic models for the iron-based superconductors.

12.
ACS Appl Mater Interfaces ; 14(37): 42494-42503, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36073747

RESUMO

Silicon suboxides (SiOx) have been widely concerned as a practical anode material for the next-generation lithium-ion batteries due to their relatively high theoretical capacity and lower volume change compared to silicon (Si). Nevertheless, traditional binder poly(vinylidene difluoride) (PVDF) still cannot hold the integrity of the SiOx particle due to its weak van der Waals force. Herein, a copolymer binder for SiOx microparticles is synthesized through a facile method of free radical polymerization between acrylamide (AM) and acrylic acid (AA). By adjusting the mass ratio of the AM/AA monomer, the copolymer binder can generate a covalent-noncovalent network with superior elastic properties from the synergistic effect. During electrochemical testing, the SiOx anode with the optimal copolymer binder (AM/AA = 3:1) delivered a reversible capacity of 734 mAh g-1 (two times that of commercial graphite) at 0.5C after 300 cycles. Thus, this work developed a green and effective strategy for synthesizing a water-soluble binder for Si-based anodes.

13.
Orthop Surg ; 14(9): 2391-2395, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35913195

RESUMO

BACKGROUND: Complete discoid medial meniscus is an extremely rare abnormality of the knee joint whose meniscus has a discoid shape rather than a normal semilunar one. Several medial meniscus anomalies including anomalous insertion have been reported in the literature. This report presents a rare case of symptomatic complete discoid medial meniscus whose anterolateral (apical) portion was completely coalesced with the ACL. MRI, radiographic, and arthroscopic findings in the medial compartment are to be submitted. CASE PRESENTATION: A 29-year-old male presented with intermittent pain and swelling of the right knee for 2 years. Based on radiographic, MRI, and physical examination findings, he was diagnosed with discoid medial meniscus tears. Arthroscopic saucerization was performed for the torn discoid medial meniscus of the right knee. Arthroscopic examination revealed a complete discoid medial meniscus and the anterolateral (apical) portion of which was completely coalesced with the ACL. Careful Probing of the meniscal surface revealed there was a longitudinal tear extending from the tibial spine to the midportion of the meniscus. Arthroscopic saucerization of the discoid meniscus was performed after closely cutting the meniscus around the ACL. The patient reported no symptoms, and he had returned to his daily and sports activities, including football, basketball, and jogging, at the 12-month follow-up. CONCLUSION: Complete discoid medial meniscus is an extremely rare abnormality, and this case presents the third complete discoid medial meniscus whose anterolateral (apical) portion was completely coalesced with the ACL. The current case we present strongly supports the hypothesis that ACL and meniscus were differentiated from the same mesenchyme.


Assuntos
Lesões do Ligamento Cruzado Anterior , Artropatias , Adulto , Ligamento Cruzado Anterior , Artroscopia , Humanos , Artropatias/diagnóstico , Articulação do Joelho/cirurgia , Imageamento por Ressonância Magnética , Masculino , Meniscos Tibiais/diagnóstico por imagem , Meniscos Tibiais/cirurgia
14.
Phys Rev Lett ; 107(16): 167001, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22107420

RESUMO

We propose a theoretical description of the phase diagram and physical properties in A(2)Fe(4)Se(5)-type (A=K, Tl) compounds based on a coexistent local moment and itinerant electron picture. Using neutron scattering and angle-resolved photoemission spectroscopy measurements to fix the general structure of the local moment and itinerant Fermi pockets, we find a superconducting phase with s-wave pairing at the M pockets and an incipient sign-change s wave near the Γ point, which is adjacent to the insulating phases. The uniform susceptibility and resistivity are found to be consistent with the experiment. The main distinction with iron pnictide superconductors is also discussed.

15.
Phys Rev Lett ; 106(14): 147002, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21561214

RESUMO

In the t-J model, the electron fractionalization is dictated by the phase string effect. We find that in the underdoped regime, the antiferromagnetic and superconducting phases are dual: in the former, holons are confined while spinons are deconfined, and vice versa in the latter. These two phases are separated by a novel phase, the so-called Bose-insulating phase, where both holons and spinons are deconfined. A pair of Wilson loops was found to constitute a complete set of order parameters determining this zero-temperature phase diagram. The quantum phase transitions between these phases are suggested to be of non-Landau-Ginzburg-Wilson type.

16.
Small Methods ; 5(6): e2100012, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34927915

RESUMO

The oxygen-related electrochemical process, including the oxygen evolution reaction and oxygen reduction reaction, is usually a kinetically sluggish reaction and thus dominates the whole efficiency of energy storage and conversion devices. Owing to the dominant role of the oxygen-related electrochemical process in the development of electrochemical energy, an abundance of oxygen-related electrocatalysts is discovered. Among them, perovskite-type materials with flexible crystal and electronic structures have been researched for a long time. However, most perovskite materials still show low intrinsic activity, which highlights the importance of activation strategies for perovskite-type structures to improve their intrinsic activity. In this review, the recent progress of the activation strategies for perovskite-type structures is summarized and their related applications in oxygen-related electrocatalysis reactions, including electrochemistry water splitting, metal-air batteries, and solid oxide fuel cells are discussed. Furthermore, the existing challenges and the future perspectives for the designing of ideal perovskite-type structure catalysts are proposed and discussed.

17.
Cell Transplant ; 29: 963689720966980, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33073597

RESUMO

The αß T-cell-depleted hematopoietic stem cell transplantation (HSCT) leads to lower relapse and better outcome, and may correlate strongly with expansion of donor-derived γδ T cells. γδ T cells play an important role in immune reconstitution and can exert a graft-versus-leukemia effect after HSCT. This review showed the recent literature on immune functions of γδ T cells after HSCT. The discrepancies between studies of γδ T cells in graft-versus-host disease may cause by its heterogeneous and various distinct subsets. And reconstitution of γδ T cells may play a potential immunoregulatory role in the infections after HSCT.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/metabolismo , Transplante de Células-Tronco Hematopoéticas/métodos , Linfócitos T/metabolismo , Transplante Homólogo/efeitos adversos , Humanos , Linfócitos T/imunologia
18.
Adv Mater ; 31(4): e1805976, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30457681

RESUMO

As one of the most widely discussed fields, the assembly of nanomaterials has always been extensively studied. However, its inverse process, namely disassembly, is still limited in the ambit of biomolecules. Specifically, in the emerging 2D research field, disassembly still remains unexplored. Inspired by the disassembly of DNA molecules via breaking intermolecular hydrogen bonds, the disassembly of 2D vertical heterostructures (2DVHs) is first achieved through the weakening of the interlayer van der Waals interactions. As a demonstration, ReS2 /WS2 VHs is successfully disassembled into individual building blocks. Density functional theory calculations are performed to study the disassembly of the 2DVHs, which simulate that 2DVHs are first activated by the disassembly promoters and then disassembled with weakened interlayer van der Waals interactions. Such a disassembly process demonstrates that it has great potential to be expanded as a general strategy to achieve the disassembly of other 2D superstructures.

19.
Sci Rep ; 8(1): 3612, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29483605

RESUMO

We investigate the ground state and excitations of finite-size Heisenberg loops doped with one hole as the simplest example to illustrate the nature of strong correlations in a doped Mott insulator. We show that the doped hole form a peculiar long-range entanglement with the surrounding spins as revealed by inspecting the mutual correlations between the charge and spin using exact diagonalization (ED). In particular, the one-hole ground state acquires a series of non-trivial total momenta depending on the ratio J/t (J and t denote the superexchange coupling and hopping integral, respectively), which gives rise to distinct quantum phases separated by critical points (CPs). Interestingly the novel total momentum and correlations completely disappear once a singular sign structure is turned off in the t-J model, indicating the latter is the true original source for strong correlation via many-body quantum interference. We emphasize that the novelties discovered here are not restricted to the one-dimensional loop. We introduce a new charge-spin mutual entanglement that can well characterize these exotic properties, which can be then easily generalized to more realistic situations like two dimensions.

20.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(3): 288-92, 2007 Jun.
Artigo em Zh | MEDLINE | ID: mdl-17557239

RESUMO

OBJECTIVE: To find out association mapping of loci related to schizophrenia on chromosome 1 with microsatellite markers in DNA pooling samples from schizophrenic cases and normal controls in Shandong peninsula. METHODS: A total of 31 microsatellite markers on chromosome 1 spaced at approximately 10 cM were scanned to two separated DNA pooling samples consisting of 119 schizophrenic cases and 119 normal controls respectively. Statistic analysis was performed by Chi-square test method to compare the difference between the ratio of each allele between the two pooling samples. RESULTS: Significant statistic difference was found at D1S2878 between cases and controls, and P< 0.01 at this loci. CONCLUSION: D1S2878 locus on chromosome 1 associates with schizophrenia in Shandong peninsula. Fine mapping and searching for candidate genes are warranted in this region.


Assuntos
Cromossomos Humanos Par 1/genética , DNA/genética , Genômica , Esquizofrenia/genética , Adulto , Estudos de Casos e Controles , China , Mapeamento Cromossômico , Feminino , Humanos , Masculino , Repetições de Microssatélites/genética , Esquizofrenia/patologia
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