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1.
Neuroradiology ; 66(3): 409-416, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38191867

RESUMO

PURPOSE: Endovascular reconstruction has emerged as a viable alternative for carotid artery dissections (CADs) that are unresponsive to antithrombotic therapy. However, high cervical and long-segment CADs pose challenges during endovascular treatment due to their distal location and tortuous anatomy. We presented our experiences using endovascular reconstruction with the Leo plus stent for this type of CAD. METHODS: We conducted a retrospective review of patients with high cervical and long-segment CADs treated using the Leo plus stent. We analyzed patient demographics, clinical presentations, procedural features, complications, and follow-up outcomes. RESULTS: A total of 17 patients (mean age, 48.1 years) with 17 CADs were identified. Seven of these dissections were accompanied by pseudoaneurysm. The mean length of the dissection was 5.7 cm, and the mean degree of stenosis was 92.3%. A single Leo plus stent was deployed in 15 patients, while another Wallstent carotid stent was used in 2 cases. All stents were successfully positioned in their intended sites. The average degree of residual stenosis was 22.2%. There were no perioperative complications. With a median follow-up duration of 29 months, no ischemic stroke events occurred. All but one Leo plus stent remained patent during follow-up, and all 7 pseudoaneurysms had disappeared at the last radiological assessment. CONCLUSION: Our experience in treating high cervical and long-segment CADs with the Leo plus stent demonstrates that this approach is practical, safe, and effective, as evidenced by long-term observations. The Leo Plus stent appears to be a suitable option for managing this type of CAD.


Assuntos
Dissecção Aórtica , Dissecação da Artéria Carótida Interna , Procedimentos Endovasculares , Humanos , Pessoa de Meia-Idade , Dissecação da Artéria Carótida Interna/diagnóstico por imagem , Dissecação da Artéria Carótida Interna/cirurgia , Constrição Patológica/complicações , Resultado do Tratamento , Stents , Estudos Retrospectivos , Artérias Carótidas
2.
Phys Rev Lett ; 131(8): 086501, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37683154

RESUMO

Strong electron correlation under two-dimensional limit is intensely studied in the transition metal dichalcogenides monolayers, mostly within their charge density wave (CDW) states that host a star of David period. Here, by using scanning tunneling microscopy and spectroscopy and density functional theory calculations with on-site Hubbard corrections, we study the VTe_{2} monolayer with a different 2sqrt[3]×2sqrt[3] CDW period. We find that the dimerization of neighboring Te-Te and V-V atoms occurs during the CDW transition, and that the strong correlation effect opens a Mott-like full gap at Fermi energy (E_{F}). We further demonstrate that such a Mott phenomenon is ascribed to the combination of the CDW transition and on-site Coulomb interactions. Our work provides a new platform for exploring Mott physics in 2D materials.

3.
Phys Rev Lett ; 131(25): 256002, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38181352

RESUMO

The Fe_{4}Se_{5} with a sqrt[5]×sqrt[5] Fe vacancy order is suggested to be a Mott insulator and the parent state of bulk FeSe superconductor. The iron vacancy ordered state has been considered as a Mott insulator and the parent compound of bulk FeSe-based superconductors. However, for the superconducting FeSe/SrTiO_{3} monolayer (FeSe/STO) with an interface-enhanced high transition temperature (T_{c}), the electronic evolution from its Fe vacancy ordered parent phase to the superconducting state, has not been explored due to the challenge to realize an Fe vacancy order in the FeSe/STO monolayer, even though important to the understanding of superconductivity mechanism. In this study, we developed a new method to generate Fe vacancies within the FeSe/STO monolayer in a tunable fashion, with the assistance of atomic hydrogen. As a consequence, an insulating sqrt[5]×sqrt[5] Fe vacancy ordered monolayer is realized as the parent state. By using scanning tunneling microscopy and scanning tunneling spectroscopy, the spectral evolution from superconductivity to insulator is fully characterized. Surprisingly, a prominent spectral weight transfer occurs, thus implying a strong electron correlation effect. Moreover, the Fe vacancy induced insulating gap exhibits no Mott gap-like features. This work provides new insights in understanding the high-T_{c} superconductivity in FeSe/STO monolayer.

4.
Neuroradiology ; 65(8): 1247-1254, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37237038

RESUMO

PURPOSE: The effect of pretreatment infarct location on clinical outcome after successful mechanical thrombectomy is not understood. Our aim was to evaluate the association between computed tomography perfusion (CTP)-based ischemic core location and clinical outcome following excellent reperfusion in late time windows. METHODS: We retrospectively reviewed patients who underwent thrombectomy for acute anterior circulation large vessel occlusion in late time windows from October 2019 to June 2021 and enrolled 65 patients with visible ischemic core on admission CTP who had received excellent reperfusion (modified thrombolysis in cerebral infarction grade 2c/3). Poor outcome was defined as a modified Rankin scale score of 3-6 at 90 days. The ischemic core infarct territories were classified into the cortical and subcortical areas. Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were used in this study. RESULTS: Of the 65 patients analyzed, 38 (58.5%) had a poor outcome. Multivariable logistic analysis showed that the subcortical infarcts (OR 11.75; 95% CI 1.79-77.32; P = 0.010) and their volume (OR 1.17; 95% CI 1.04-1.32; P = 0.011) were independently associated with poor outcome. The ROC curve indicated the capacity of the subcortical infarct involvement (areas under the curve (AUC) = 0.65; 95% CI, 0.53-0.77, P < 0.001) and subcortical infarct volume (AUC = 0.72; 95% CI, 0.60-0.83, P < 0.001) in predicting poor outcome accurately. CONCLUSION: Subcortical infarcts and their volume on admission CTP are associated with poor outcome after excellent reperfusion in late time windows, rather than cortical infarcts.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/cirurgia , Trombectomia/métodos , Reperfusão , Resultado do Tratamento
5.
J Comput Assist Tomogr ; 47(5): 806-810, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37707412

RESUMO

OBJECTIVES: A large quantity of ischemic stroke events occur in patients hospitalized for non-stroke-related reason. No scale has been developed to identify the large vessel occlusion (LVO) among inpatient stroke alerts. We aimed to develop a novel evaluation scale to predict LVO from in-hospital stroke alerts. METHODS: Data from consecutive in-hospital stroke alerts were analyzed at a single high volume stroke center between January 2016 and October 2020. We developed a predictive scale based on the first half of patients (training group) using multivariate logistic regression and evaluated it in the remaining half of patients (validation group) adopting receiver operating curve. Receiver operating characteristics of the scale were analyzed to evaluate its value for the detection of LVO. RESULTS: A total of 243 patients were enrolled for further study, among them, 94 (38.7%) had confirmed LVO. Three risk factors independently predicted the presence of LVO: recent cardiac or pulmonary procedure (1 point), neurological deficit scale (≥1: 2 points), and history of atrial fibrillation (1 point). The CAPS scale was generated based on predictive factors and demonstrated highly effective discrimination in identifying the presence of LVO in the training group (area under curve = 0.956) and the validation group (area under curve = 0.940). When the score ≥2, CAPS scale showed 97.9% sensitivity, 79.2% specificity, 74.8% positive predictive value, and 98.3% negative predictive value for discriminating LVO. CONCLUSIONS: CAPS scale was developed for identifying LVO among inpatient stroke alerts with high sensitivity and specificity, which may help to quickly prompt responses by appropriate stroke teams.


Assuntos
Arteriopatias Oclusivas , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Pacientes Internados , Acidente Vascular Cerebral/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Retrospectivos
6.
J Comput Assist Tomogr ; 47(4): 671-676, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37365699

RESUMO

OBJECTIVE: To investigate whether truncal-type occlusion based on multiphase computed tomographic angiography (mpCTA) was more effective for predicting intracranial atherosclerotic stenosis-related occlusion (ICAS-O) than occlusion type based on single-phase computed tomographic angiography (spCTA) in patients with acute ischemic stroke with large-vessel occlusion (AIS-LVO) in the middle cerebral artery (MCA). METHODS: Data were retrospectively collected from 72 patients with AIS-LVO in the MCA between January 2018 and December 2019. The occlusion types included truncal-type and branching-site occlusions. The association between ICAS-O and occlusion type based on the 2 computed tomographic angiography patterns was analyzed, and receiver operating characteristic curves were plotted for assessment. The areas under the curve were compared to determine the difference between the predictive powers of truncal-type occlusion based on mpCTA and spCTA. RESULTS: Among the 72 patients, 16 were classified as having ICAS-O and 56 as having embolisms. In univariate analysis, truncal-type occlusion was significantly associated with ICAS-O ( P < 0.001 for mpCTA and P = 0.001 for spCTA). After multivariable analysis, truncal-type occlusion based on both mpCTA and spCTA remained independently associated with ICAS-O ( P = 0.002 for mpCTA and P = 0.029 for spCTA). The areas under the curve were 0.821 for mpCTA and 0.683 for spCTA; this difference was statistically significant ( P = 0.024). CONCLUSIONS: In patients with AIS-LVO in the MCA, truncal-type occlusion based on mpCTA enables more accurate detection of ICAS-O than that based on spCTA.


Assuntos
Arteriosclerose Intracraniana , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Estudos Retrospectivos , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/complicações , Angiografia Cerebral/métodos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem
7.
Acta Radiol ; 64(3): 1139-1147, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35575229

RESUMO

BACKGROUND: Intracranial atherosclerosis-related large vessel occlusion (ICAS+LVO) poses an important technical challenge for endovascular thrombectomy (EVT). PURPOSE: To evaluate the value of D-dimer in predicting ICAS+LVO alone and in combination with other clinical and imaging predictors. MATERIAL AND METHODS: Consecutive patients who underwent EVT at our center between January 2018 and June 2021 were retrospectively reviewed. Patients were classified to the ICAS+LVO or ICAS-LVO group according to angiographic findings. Collateral gradings were evaluated based on computed tomography angiography and categorized as follows: score 0-1 unfavorable collaterals and score 2-3 favorable collaterals. Receiver operating characteristic curve was analyzed to evaluate the predictive value of D-dimer and the combination of other predictors for ICAS+LVO. RESULTS: A total of 374 patients were enrolled, among them, 107 (28.6%) had an ICAS+LVO, while ICAS-LVO was determined in 267 (71.4%) patients. Median D-dimer levels were lower (0.36 vs. 1.18 mg/L; P < 0.001) while the proportion of favorable collaterals was higher (85.0% vs. 22.5%; P < 0.001) in the ICAS+LVO group than the ICAS-LVO group. After multivariable analysis, D-dimer (adjusted odds ratio [OR]=0.32, 95% confidence interval [CI]=0.21-0.50; P < 0.001) and collaterals (adjusted OR=16.25, 95% CI=7.58-34.84; P < 0.001) remained independent predictors of ICAS+LVO. The area under the curve of D-dimer, collaterals, and combination for identification of ICAS+LVO was 0.82, 0.85, and 0.92, respectively. CONCLUSION: Low early plasma D-dimer levels are a significant and independent predictor of ICAS+LVO, and predictive value strengthens when in a combined model using D-dimer and collateral grading.


Assuntos
Arteriosclerose Intracraniana , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , AVC Isquêmico/diagnóstico por imagem , Estudos Retrospectivos , Trombectomia/métodos , Acidente Vascular Cerebral/diagnóstico por imagem
8.
Eur J Neurol ; 29(6): 1643-1651, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35143095

RESUMO

BACKGROUND AND PURPOSE: DIRECT-MT showed that endovascular thrombectomy was noninferior to thrombectomy preceded by intravenous alteplase with regard to functional outcome in patients with acute ischemic stroke. In this post hoc analysis, we examined whether infarct size modified the effect of alteplase. METHODS: All patients with baseline Alberta Stroke Program Early Computed Tomography Score (ASPECTS) grades were included. The primary outcome was the 90-day modified Rankin Scale (mRS) score. Multivariate ordinal logistic regression analysis was used to calculate the adjusted common odds ratio (OR) for better functional outcome based on the mRS for thrombectomy alone versus combination therapy. An interaction term was entered to test for an interaction with baseline ASPECTS subgroups: 0-4 versus 5-7 versus 8-10. RESULTS: Of 649 patients, 323 (49.8%) were in the thrombectomy-alone group and 326 (50.2%) in the combination-therapy group. There was no significant treatment-by-trichotomized ASPECTS interaction with alteplase prior to endovascular treatment for the primary endpoint of ordinal mRS (p-value interaction term relative to ASPECTS 8-10: ASPECTS 0-4, p = 0.386; ASPECTS 5-7, p = 0.936). Adjusted common ORs for improvement in the 90-day mRS with thrombectomy alone compared with combination therapy were 1.99 (95% confidence interval = 0.72-5.46) for ASPECTS 0-4, 1.07 (0.62-1.86) for ASPECTS 5-7, and 1.03 (0.74-1.45) for ASPECTS 8-10. There was no significant difference in the safety outcomes between the two groups. CONCLUSIONS: Baseline infarct size may not modify the effect of alteplase prior to endovascular thrombectomy with regard to favorable functional outcomes and adverse events.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/tratamento farmacológico , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Humanos , Infarto/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
9.
BMC Neurol ; 22(1): 380, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209054

RESUMO

BACKGROUND: Oculomotor nerve palsy (ONP) may result from posterior communicating artery (PcomA) aneurysms. We aimed to evaluate the resolution of ONP after endovascular treatment with the intention of clarifying predictors of nerve recovery in a relatively large series. METHODS: A total of 211 patients with ONP caused by PcomA aneurysms underwent endovascular coiling between May 2010 and December 2020 in four tertiary hospitals. We evaluated the demographics, clinical characteristics, aneurysm morphology parameters and ONP resolution to analyze the predictors of ONP recovery using univariate and multivariate analyses. RESULTS: At the last available clinical follow-up, ONP resolution was complete in 126 (59.7%) patients, partial in 73 (34.6%) patients, and no recovery in 12 (5.7%) patients. The median resolution time after endovascular treatment was 55 days (interquartile range: 40-90 days). In multivariate analysis, degree of ONP (incomplete palsy) on admission (OR 5.396; 95% CI 2.836-10.266; P < 0.001), duration of ONP (≤ 14 days) before treatment (OR 5.940; 95% CI 2.724-12.954; P < 0.001) were statistically significant predictors of complete recovery of ONP. In the subgroup analysis of patients with unruptured aneurysms, aspirin showed a higher complete recovery rate in univariate analysis (OR 2.652; 95% CI 1.057-6.656; P = 0.038). CONCLUSION: Initial incomplete ONP and early management might predict better recovery of ONP after endovascular treatment.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Doenças do Nervo Oculomotor , Aspirina/uso terapêutico , Embolização Terapêutica/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , Doenças do Nervo Oculomotor/etiologia , Doenças do Nervo Oculomotor/terapia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
10.
Acta Radiol ; 63(5): 658-663, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33827276

RESUMO

BACKGROUND: Patients with acute ischemic stroke (AIS) caused by large vessel occlusion (LVO) were usually transferred from a primary stroke center (PSC) to a comprehensive stroke center (CSC) for endovascular treatment (drip-and-ship [DS]), while driving the doctor from a CSC to a PSC to perform a procedure is an alternative strategy (drip-and-drive [DD]). PURPOSE: To compare the efficacy and prognosis of the two strategies. MATERIAL AND METHODS: From February 2017 to June 2019, 62 patients with LVO received endovascular treatment via the DS and DD models and were retrospectively analyzed from the stroke alliance based on our CSC. Primary endpoint was door-to-reperfusion (DTR) time. Secondary endpoints included puncture-to-recanalization (PTR) time, modified Thrombolysis in Cerebral Infarction (mTICI) rates at the end of the procedure, and modified Rankin Scale (mRS) at 90 days. RESULTS: Forty-one patients received the DS strategy and 21 patients received the DD strategy. The DTR time was significantly longer in the DS group compared to the DD group (315.5 ± 83.8 min vs. 248.6 ± 80.0 min; P < 0.05), and PTR time was shorter (77.2 ± 35.9 min vs. 113.7 ± 69.7 min; P = 0.033) compared with the DD group. Successful recanalization (mTICI 2b/3) was achieved in 89% (36/41) of patients in the DS group and 86% (18/21) in the DD group (P = 1.000). Favorable functional outcomes (mRS 0-2) were observed in 49% (20/41) of patients in the DS group and 71% (15/21) in the DD group at 90 days (P = 0.089). CONCLUSION: Compared with the DS strategy, the DD strategy showed more effective and a trend of better clinical outcomes for AIS patients with LVO.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/métodos , Humanos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Transferência de Pacientes , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia , Terapia Trombolítica/métodos , Resultado do Tratamento
11.
Acta Radiol ; 63(3): 393-400, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33541090

RESUMO

BACKGROUND: Higher baseline Alberta Stroke Program Early Computed Tomography Score (ASPECTS) was associated with a lower probability of hemorrhagic transformation in patients with acute ischemic stroke (AIS). PURPOSE: To investigate the predictive value of cerebral blood volume (CBV)-ASPECTS of intracranial hemorrhage (ICH) in AIS treated with thrombectomy selected by computed tomographic perfusion (CTP) in an extended time window. MATERIAL AND METHODS: A total of 91 consecutive patients with AIS with large vessel occlusion in the anterior circulation after thrombectomy in an extended time window were enrolled between January 2018 and September 2019. ICH was diagnosed according to Heidelberg Bleeding Classification. CBV-ASPECTS was assessed by evaluating each ASPECTS region for relatively low CBV value compared with the mirror region in the contralateral hemisphere. Demographic characteristics, clinical data, CBV-ASPECTS, and procedure process and results were compared between patients with ICH and those without. RESULTS: ICH occurred in 31/91 (34.1%) patients with AIS. Symptomatic ICH (sICH) was observed in 4 (4.4%) patients, while asymptomatic ICH (aICH) was seen in 27 (29.7%). In univariate analysis, both ICH and aICH were associated with high admission NIHSS score (P<0.001 and P<0.001, respectively), more passes of retriever (P = 0.007 and P = 0.019, respectively), low NCCT-ASPECTS (P = 0.013 and P = 0.034, respectively), and low CBV-ASPECTS (P < 0.001 and P < 0.001, respectively). After multivariable analysis, low CBV-ASPECTS remained an independent predictor of ICH (odds ratio [OR] 0.521, 95% confidence interval [CI] 0.371-0.732, P < 0.001) and aICH (OR 0.532, 95% CI 0.376-0.752, P < 0.001), respectively. CONCLUSION: Low CBV-ASPECTS independently predicts ICH in patients with AIS treated with thrombectomy selected by CTP in an extended time window.


Assuntos
Volume Sanguíneo Cerebral , Hemorragias Intracranianas/diagnóstico , AVC Isquêmico/cirurgia , Trombólise Mecânica/métodos , Tomografia Computadorizada Multidetectores , Complicações Pós-Operatórias/diagnóstico , Doença Aguda , Idoso , Análise de Variância , Doenças Assintomáticas/epidemiologia , Circulação Cerebrovascular , Intervalos de Confiança , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/cirurgia , Hemorragias Intracranianas/epidemiologia , AVC Isquêmico/diagnóstico por imagem , Masculino , Complicações Pós-Operatórias/epidemiologia , Valor Preditivo dos Testes , Proteínas Recombinantes/administração & dosagem , Estudos Retrospectivos , Fatores de Tempo , Ativador de Plasminogênio Tecidual/administração & dosagem , Tomografia Computadorizada Espiral/métodos
12.
Neuroradiology ; 63(9): 1521-1530, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33630124

RESUMO

PURPOSE: Before we enter the era of flow diverter stents (FDS), the standard stent-assisted coiling technique is a well-established treatment option for routine paraclinoid aneurysms. We assess the clinical safety and efficacy of stent-assisted coiling with open-cell stent in the treatment of paraclinoid aneurysms and evaluate the association between clinical factors and follow-up aneurysm occlusion. METHODS: The clinical and radiographic data of 110 consecutive patients with 122 paraclinoid aneurysms treated with open-cell stent between April 2015 and April 2019 were analyzed retrospectively at our center. We assessed the immediate and progressive occlusion rates, complications, and clinical outcome. Multivariate analysis was performed to investigate the risk factors of angiographic incomplete occlusion. RESULTS: Among 110 patients, stent-assisted coiling was successfully performed in all cases. Four (3.6%) thromboembolic events were reported during the procedure, which resulted in transient morbidity. Immediate angiography demonstrated complete occlusion in 64 (52.5%) aneurysms and no occlusion of ophthalmic artery. Angiographic follow-up at 6 months demonstrated an increase in the complete occlusion rate to 92.9%. No delayed in-stent stenosis was observed, and three aneurysms recurred. Clinical follow-up was completed in 102 patients (92.7%), and favorable outcomes were achieved in 101 (99%) patients at 6 months. Multivariate analysis showed that aneurysm size (p < 0.001) was associated with incomplete aneurysm occlusion at follow-up. CONCLUSION: Stent-assisted coil embolization with open-cell stents is safe and effective for the treatment of paraclinoid aneurysms and provides progressive occlusion without significant in-stent stenosis events.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Prótese Vascular , Angiografia Cerebral , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Estudos Retrospectivos , Stents , Resultado do Tratamento
13.
Nano Lett ; 20(11): 8408-8414, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33064495

RESUMO

The interfacial charge transfer from the substrate may influence the electronic structure of the epitaxial van der Waals (vdW) monolayers and, thus, their further technological applications. For instance, the freestanding Sb monolayer in the puckered honeycomb phase (α-antimonene), the structural analogue of black phosphorene, was predicted to be a semiconductor, but the epitaxial one behaves as a gapless semimetal when grown on the Td-WTe2 substrate. Here, we demonstrate that interface engineering can be applied to tune the interfacial charge transfer and, thus, the electron band of the epitaxial monolayer. As a result, the nearly freestanding (semiconducting) α-antimonene monolayer with a band gap of ∼170 meV was successfully obtained on the SnSe substrate. Furthermore, a semiconductor-semimetal crossover is observed in the bilayer α-antimonene. This study paves the way toward modifying the electron structure in two-dimensional vdW materials through interface engineering.

14.
J Stroke Cerebrovasc Dis ; 30(8): 105872, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34153591

RESUMO

PURPOSE: To compare the ischemic core volume estimated by CT Perfusion 4D and Vue PACS with that estimated by RAPID software in acute ischemic stroke (AIS). MATERIALS AND METHODS: CT perfusion data from AIS patients were retrospectively post-processed with RAPID, CT Perfusion 4D and Vue PACS software. The Vue PACS application included three different settings: method A (Circular Singular Value Decomposition), method B (Oscillating index Singular Value Decomposition) and method C (Standard Singular Value Decomposition). Bland-Altman analysis, intraclass correlation coefficients (ICCs) and Kappa analysis were used to evaluate concordance between estimated ischemic core values. Final infarct volume (FIV) was measured by follow-up non-contrast CT or MRI 5-7 days after mechanical thrombectomy (MT) in patients with successful recanalization. RESULTS: A total of 82 patients were included in the study. Concordance with RAPID ranged from good (method B: ICC 0.780; method C: ICC 0.852) to excellent (CT perfusion 4D: ICC 0.950; method A: ICC 0.954). The limits of agreement (-32.3, 41.8 mL) were the narrowest with method A. For detecting core volumes ≤ 70 ml, method A and CT perfusion 4D showed almost perfect concordance with RAPID (CT perfusion 4D, kappa=0.87; method A, kappa=0.87), whereas methods B and C showed substantial concordance with RAPID (method B, kappa=0.77; method C, kappa =0.73). Thirty-two patients had good reperfusion after MT. RAPID showed the highest accuracy for predicting FIV, followed by method A. CONCLUSION: CT perfusion 4D and Vue PACS method A showed excellent concordance with RAPID for quantifying ischemic core volume, which can be considered as alternatives in selecting patients for MT in clinical practice.


Assuntos
Circulação Cerebrovascular , AVC Isquêmico/diagnóstico por imagem , Imagem de Perfusão , Interpretação de Imagem Radiográfica Assistida por Computador , Software , Tomografia Computadorizada por Raios X , Idoso , Tomada de Decisão Clínica , Feminino , Humanos , AVC Isquêmico/fisiopatologia , AVC Isquêmico/terapia , Imageamento por Ressonância Magnética , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Trombectomia , Resultado do Tratamento
15.
Angew Chem Int Ed Engl ; 60(21): 11702-11706, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33694297

RESUMO

A facile method for the quantitative preparation of silver dibenzo-fused corrole Ag-1 is described. In contrast to the saddle conformation resolved by single-crystal X-ray analysis for Ag-1, it adopts an unprecedented domed geometry, with up and down orientations, when adsorbed on an Ag(111) surface. Sharp Kondo resonances near Fermi level, both at the corrole ligand and the silver center were observed by cryogenic STM, with relatively high Kondo temperature (172 K), providing evidence for a non-innocent AgII -corrole.2- species. Further investigation validates that benzene ring fusion and molecule-substrate interactions play pivotal roles in enhancing Ag(4d(x2 -y2 ))-corrole (π) orbital interactions, thereby stabilizing the open-shell singlet AgII -corrole.2- on Ag(111) surface. Moreover, this strategy used for constructing metal-free benzene-ring fused corrole ligand gives rise to inspiration of designing novel metal-corrole compound for multichannel molecular spintronics devices.

17.
Phys Rev Lett ; 123(20): 206405, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31809103

RESUMO

Metallization of 1T-TaS_{2} is generally initiated at the domain boundary of a charge density wave (CDW), at the expense of its long-range order. However, we demonstrate in this study that the metallization of 1T-TaS_{2} can be also realized without breaking the long-range CDW order upon surface alkali doping. By using scanning tunneling microscopy, we find the long-range CDW order is always persisting, and the metallization is instead associated with additional in-gap excitations. Interestingly, the in-gap excitation is near the top of the lower Hubbard band, in contrast to a conventional electron-doped Mott insulator where it is beneath the upper Hubbard band. In combination with the numerical calculations, we suggest that the appearance of the in-gap excitations near the lower Hubbard band is mainly due to the effectively reduced on-site Coulomb energy by the adsorbed alkali ions.

18.
Nano Lett ; 18(10): 6585-6590, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30226053

RESUMO

To realize a topological superconductor is one of the most attracting topics because of its great potential in quantum computation. In this study, we successfully intercalate potassium (K) into the van der Waals gap of type II Weyl semimetal WTe2 and discover the superconducting state in K xWTe2 through both electrical transport and scanning tunneling spectroscopy measurements. The superconductivity exhibits an evident anisotropic behavior. Moreover, we also uncover the coexistence of superconductivity and the positive magnetoresistance state. Structural analysis substantiates the negligible lattice expansion induced by the intercalation, therefore suggesting K-intercalated WTe2 still hosts the topological nontrivial state. These results indicate that the K-intercalated WTe2 may be a promising candidate to explore the topological superconductor.

19.
Acta Neurochir (Wien) ; 160(9): 1755-1760, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30056517

RESUMO

BACKGROUND: Although paraclinoid aneurysms do not exhibit a high risk of rupture, coil embolization is not always easy because of unstable microcatheter position. We present a technique that allows a stable microcatheter position for coil embolization of paraclinoid aneurysms. METHODS: We enrolled 34 consecutive patients who underwent coil embolization for paraclinoid aneurysms. A loop of distal microcatheter was shaped based on three-dimensional rotational angiography. The basic concept is to keep the proximal loop abutting the opposite wall of the aneurysm while using the distal loop for coiling. Then, a proximal curve was made to accommodate the shape of the carotid siphon, which may decide the direction of the loop. Stent-assisted coil embolization was performed in 19 wide-necked aneurysms. Immediate radiological outcomes were analyzed with Raymond classification and clinical outcomes were evaluated with modified Rankin Scale (mRS) scores. RESULTS: Satisfactory occlusion of aneurysm was achieved in 94.1% (32/34) of patients with a Raymond score of 1 or 2. Packing density of ≥ 31% was achieved in 71% (24/34) of patients. No significant differences were observed between stent-assisted coiling and coiling-only groups. Follow-up magnetic resonance angiography and/or angiogram showed stable coil position, except in one patient with tiny recurrence (from Raymond scores 1 to 2) that did not require retreatment at the 6-month follow-up. mRS scores of 0-1 were obtained in all patients at 6 months. CONCLUSIONS: Loop microcatheter technique allowed safe and stable coil packing for paraclinoid aneurysms. The same procedural concept is also being used for aneurysms in other vascular territories.


Assuntos
Embolização Terapêutica/métodos , Aneurisma Intracraniano/terapia , Idoso , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/patologia , Angiografia Cerebral/métodos , Embolização Terapêutica/efeitos adversos , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
20.
Knee Surg Sports Traumatol Arthrosc ; 26(10): 2997-3003, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29404654

RESUMO

PURPOSE: The aim of this study is to obtain a translation and adaptation of the anterior cruciate ligament-return to sport after injury (ACL-RSI) into simplified Chinese and validate the simplified Chinese version. METHODS: Translation and adaptation were performed according to the guidelines of the American Academy of Orthopaedic Surgeons Outcome Committee. A total of 122 patients who were diagnosed with an ACL injury and underwent primary arthroscopic anterior cruciate ligament reconstruction (ACLR) between 2015 and 2016 were included in this study. The simplified Chinese version of the ACL-RSI (SC-ACL-RSI), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm score and International Knee Documentation Committee (IKDC) subjective knee form were completed. Psychometric evaluations included score distribution, internal consistency, test-retest reliability, and construct and discriminant validity. RESULTS: SC-ACL-RSI scores exhibited a normal distribution without ceiling and floor effects. Internal consistency was high (Cronbach's alpha = 0.94). The intraclass correlation coefficient was 0.98, indicating excellent test-retest reliability. SC-ACL-RSI scores were correlated with all KOOS subscales (r = 0.30 to 0.69, p < 0.001), the IKDC subjective knee form (r = 0.46, p < 0.001) and the Lysholm score (r = 0.56, p < 0.001). The mean scores between patients who returned to the same preinjury level of sport (65.1 ± 14.3) and those who could not return to the same level (51.0 ± 15.0) were significantly different (p < 0.001). CONCLUSIONS: The SC-ACL-RSI is a reliable and valid instrument to evaluate the psychological impact of a patient returning to sport after ACLR. It is important to evaluate patients' ability to return to sport after an ACL injury. The information provided by the SC-ACL-RSI will affect decisions regarding treatment and rehabilitation plans, which are more likely to influence clinical outcomes. LEVEL OF EVIDENCE: II.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Volta ao Esporte , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Artroscopia , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Traduções , Adulto Jovem
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