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1.
Small ; : e2404913, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235369

RESUMO

Materials with circularly polarized luminescence (CPL) exhibit great application potential in biological scenes such as cell imaging, optical probes, etc. However, most developed materials are non-aqueous and toxic, which seriously restricts their compatibility with the life systems. Thus, it is necessary to explore a water-based CPL system with high biocompatibility so that to promote the biologic application process. Herein, a facile and efficient route to achieve the CPL properties of a functional aqueous solution is demonstrated by the combination of 0D quantum dots (QDs) and 2D chiral nanosheets. Benefited by the specific absorption ability of nanosheets for left/right-handed CPL, the QDs adsorbed onto the surface of nanosheets through hydrogen bond interactions showed apparent CPL features. In addition, this system has a good extensibility as the CPL property can be effectively regulated by changing the kind of emissive QDs. More importantly, this water-based nano-composite with facile fabrication process (one-step mixing) is suitable for the real applications, which is undoubtedly beneficial for the further progress of functional CPL materials.

2.
Rev Cardiovasc Med ; 25(2): 69, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39077355

RESUMO

Background: Studies reporting the status of coronary microvascular function in the infarct-related artery (IRA) after primary percutaneous coronary intervention (PCI) remain limited. This study utilized the coronary angiography-derived index of microcirculatory resistance (caIMR) to assess coronary microvascular function in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI. Methods: We used the FlashAngio system to measure the caIMR after primary PCI in 157 patients with STEMI. The primary endpoint was the occurrence of a major adverse cardiovascular event (MACE), defined as a composite endpoint encompassing cardiac mortality, target vessel revascularization, and rehospitalization due to congestive heart failure (CHF), myocardial infarction (MI), or angina. Results: Approximately 30% of patients diagnosed with STEMI and who experienced successful primary PCI during the study period had a caIMR in the IRA of > 40. The caIMR in the IRA was significantly higher than in the reference vessel (32.9 ± 15.8 vs. 27.4 ± 11.1, p < 0.001). The caIMR in the reference vessel of the caIMR > 40 group was greater than in the caIMR ≤ 40 group (30.9 ± 11.3 vs. 25.9 ± 10.7, p = 0.009). Moreover, the caIMR > 40 group had higher incidence rates of MACEs at 3 months (25.5% vs. 8.3%, p = 0.009) and 1 year (29.8% vs. 13.9%, p = 0.04), than in the caIMR ≤ 40 group, which were mainly driven by a higher rate of rehospitalization due to CHF, MI, or angina. A caIMR in the IRA of > 40 was an independent predictor of a MACE at 3 months (hazard ratio (HR): 3.459, 95% confidence interval (CI): 1.363-8.779, p = 0.009) and 1 year (HR: 2.384, 95% CI: 1.100-5.166, p = 0.03) in patients with STEMI after primary PCI. Conclusions: Patients with STEMI after primary PCI often have coronary microvascular dysfunction, which is indicated by an increased caIMR in the IRA. An elevated caIMR of > 40 in the IRA was associated with an increased risk of adverse outcomes in STEMI patients undergoing primary PCI.

3.
Angew Chem Int Ed Engl ; 63(39): e202409782, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38888844

RESUMO

A stimuli-responsive multiple chirality switching material, which can regulate opposed chiral absorption characteristics, has great application value in the fields of optical modulation, information storage and encryption, etc. However, due to the rareness of effective functional systems and the complexity of material structures, developing this type of material remains an insurmountable challenge. Herein, a smart polymer film with multiple chirality inversion properties was fabricated efficiently based on a newly-designed acid & base-sensitive dye-grafted helical polymer. Benefited from the cooperative effects of various weak interactions (hydrogen bonds, electrostatic interaction, etc.) under the aggregated state, this polymer film exhibited a promising acid & base-driven multiple chirality inversion property containing record switchable chiral states (up to five while the solution showed three-state switching) and good reversibility. The creative exploration of such a multiple chirality switching material can not only promote the application progress of current chiroptical regulation technology, but also provide a significant guidance for the design and synthesis of future smart chiroptical switching materials and devices.

4.
Rev Cardiovasc Med ; 23(10): 330, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39077139

RESUMO

Background: There are scarce published data reporting the effect of rotational atherectomy (RA) on coronary microcirculation function. Objectives: We aimed to evaluate coronary microcirculation function indicated by the coronary angiography-derived index of microvascular resistance (caIMR) in patients undergoing RA. Methods: RA procedures between January 2013 and December 2021 were retrospectively analyzed. We investigated coronary microcirculation function indicated by caIMR as well as peri-procedural adverse events among the study population. All caIMR measurements were performed using a FlashAngio system. The primary outcome was a composite of post-RA thrombolysis in myocardial infarction (TIMI) flow grade < 3 in the target vessel, myocardial injury, procedure-related myocardial infarction, and cardiac death during hospitalization. Results: A total of 155 RA procedures were analyzed. The post-RA caIMRs were significantly higher than pre-RA caIMRs in the target vessels (16.0 ± 7.0 vs. 14.5 ± 7.5, p = 0.029). Patients with post-RA caIMR ≥ 25 accounted for nearly 12% of those with pre-RA caIMR < 25. Patients with post-RA thrombolysis in myocardial infarction (TIMI) flow grade < 3 had a significantly higher pre-RA caIMR (23.5 ± 10.2 vs. 13.7 ± 6.6, p = 0.005), and the proportion of patients with pre-RA caIMR ≥ 25 in the group with TIMI flow grade < 3 was greater (61.5% vs. 38.5%, p < 0.001) than that in the group with TIMI flow grade of 3. Maximum RA time of each pass (odds ratio: 1.127, 95% confidence interval: 1.025-1.239, p = 0.014) and pre-RA caIMR ≥ 25 (odds ratio: 3.254, 95% confidence interval: 1.054-10.048, p = 0.040) were identified to be the independent predictors of the primary outcome for patients who underwent RA. Conclusions: There were significant changes in the coronary microcirculation function of the target vessels after receiving RA as indicated by increased post-RA caIMR compared to pre-RA caIMR. Patients with baseline coronary microcirculatory dysfunction were more likely to have post-RA TIMI flow grade < 3, whereas those with pre-RA caIMR ≥ 25 experienced worse outcomes.

5.
BMC Cardiovasc Disord ; 21(1): 399, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34407770

RESUMO

OBJECTIVES: To evaluate the safety and efficacy of excimer laser coronary atherectomy (ELCA) in patients with in-stent restenosis chronic total occlusions (ISR CTOs). BACKGROUND: ISR CTOs are a challenge in percutaneous coronary intervention (PCI). Although they can be treated by ELCA, limited data are available on the effects of ELCA treatment in these patients. METHODS: Fifty-nine consecutive patients underwent PCI for ISR CTOs at Beijing Hospital between December 2017 and September 2020. According to whether or not ELCA was performed, they were divided into two groups. Quantitative coronary angiography (QCA) analyses were performed routinely, including measurement of the minimal lumen diameter and calculation of the percentage diameter stenosis. The procedural success rate, the frequency of peri-procedural complications, and the incidence rates of major adverse cardiac events (MACEs) over nine months were assessed. The primary endpoint in the study was the percentage diameter stenosis. RESULTS: Procedure success was achieved in most patients in both groups (75.9%). Patients in the ELCA group exhibited a lower percentage diameter stenosis (24.5 ± 9.09 vs. 35.1 ± 18.6, p = 0.048) and a larger minimal lumen diameter (2.36 ± 0.29 mm vs. 1.78 ± 0.64 mm, p < 0.001) than those in the control group and the 9-month incidence rates of MACEs did not differ (9.5% vs 15.8%, p = 0.699). CONCLUSIONS: This study demonstrated that ELCA may be a safe and effective technique in the treatment of ISR CTOs, and the use of ELCA can achieve good immediate angiographic results, as measured by QCA, without increasing peri-procedural complications or the incidence rates of 9-month MACEs.


Assuntos
Aterectomia Coronária/instrumentação , Oclusão Coronária/terapia , Reestenose Coronária/terapia , Lasers de Excimer/uso terapêutico , Intervenção Coronária Percutânea/efeitos adversos , Idoso , Aterectomia Coronária/efeitos adversos , Pequim , Doença Crônica , Angiografia Coronária , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/etiologia , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/etiologia , Feminino , Humanos , Lasers de Excimer/efeitos adversos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/instrumentação , Estudos Retrospectivos , Stents , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção
6.
Chem Soc Rev ; 49(23): 8687-8720, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33078186

RESUMO

Electrochromic devices (ECDs) have been regarded as promising candidates for energy-saving smart windows, next-generation displays and wearable electronics due to their significant benefits of simple and adjustable structures, low power consumption, flexible and stretchable features, and eye-friendly modes for displays. However, there are many existing issues waiting to be solved such as durability, reversibility and inadequate switching performances. These insurmountable technical bottlenecks significantly slow down the commercialization of next-generation ECDs. Nanomaterials with superior active reaction surface area have played indispensable roles in optimizing heterogeneous electron transfer and homogeneous ion transfer for ECDs and other optoelectronic devices. In recent years, with the joint efforts of various outstanding research teams, new kinds and methods for nanomaterials to fabricate ECDs with excellent performances have been rapidly developing. This review highlights the latest exciting results regarding the design and application of new and unique nanomaterials for each layer of ECDs. Meanwhile, the structures, mechanisms, features and preparation of the reported nanomaterials to improve the electrochromic properties have been discussed in detail. In addition, the remaining challenges and corresponding strategies of this field are also proposed. Hopefully, this review can inspire more and more researchers to enrich the nanomaterials for ECDs and other related fields to overcome faced technical barriers by innovative means and promote industrialization of ECDs and other optoelectronic technologies.

7.
Angew Chem Int Ed Engl ; 60(4): 2018-2023, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-32885573

RESUMO

A new and simple strategy towards electric-field-driven multiple chirality switching device has been designed and fabricated by combining a newly synthesized base-responsive chiroptical polymer switch (R-FLMA) and p-benzoquinone (p-BQ) via proton-coupled electron transfer (PCET) mechanism. Clear and stable triple chirality states (silence, positive, negative) of this device in visible band can be regulated reversibly (>1000 cycles) by adjusting voltage programs. Furthermore, such chiral switching phenomena are also accompanied by apparent changes of color and fluorescence. More importantly, the potential application of this device for a spatial light modulator has also been demonstrated.

8.
Opt Express ; 27(5): 7384-7392, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876303

RESUMO

Adiabatic quantum control is a very important approach for quantum physics and quantum information processing (QIP). It holds the advantage with robustness to experimental imperfections but accumulates more decoherence due to the long evolution time. Here, we propose a universal protocol for fast and robust quantum control in multimode interactions of a quantum system by using shortcuts to adiabaticity. The results show this protocol can speed up the evolution of a multimode quantum system effectively, and it can also keep the robustness very good while adiabatic quantum control processes cannot. We apply this protocol for the quantum state transfer in QIP in the photon-phonon interactions in an optomechanical system, showing a perfect result. These good features make this protocol have the capability of improving effectively the feasibility of the practical applications of multimode interactions in QIP in experiment.

9.
Org Biomol Chem ; 16(12): 2114-2124, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29512675

RESUMO

Fully-conjugated styrylbenzoxazoles and styrylbenzothiazoles of BOAF24, BOACl24, BOACl35, BOABr24, BOABr35, BTAF24, BTACl24 and BTABr24 without traditional gelation groups could form organogels. It was found that introduction of chlorine atoms in the 2,4-positions of the phenyl group would improve gelation abilities, and benzothiazole derivatives exhibited better gelation abilities than benzoxazoles with a similar π-skeleton due to better π-electron delocalization. Interestingly, the organogel of BTACl24 could change into solution by UV light due to trans-cis isomerization, which could also induce morphological changes in xerogels. The smooth organogel nanofibers stretched out lots of thin 'arms' to hold together or to catch other nanofibers upon UV irradiation, so more entangled networks were generated. Moreover, TFA (trifluoroacetic acid) could induce a gel-sol transformation on account of the protonation of the benzoxazole or benzothiazole unit, accompanied by emission quenching. BTACl24 exhibited higher performance than BOACl24 in the detection of TFA because of its strong basicity. The decay time and the detection limit of BTACl24 in xerogel-based film towards TFA vapor were of 0.7 s and 0.3 ppm, respectively. Therefore, organogelation of non-traditional organogelators is a powerful approach to the fabrication of multi-stimuli-responsive soft materials, and provides a new method to generate more entangled 3D networks through photochemical reactions in xerogels.

11.
Opt Express ; 23(3): A51-61, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25836253

RESUMO

In present study, the intense sensitized three photon near-infrared quantum cutting luminescence of Tm(3+) ion activator in Tm(3+)Bi(3+):YNbO(4) powder phosphor is reported. It is induced both by [{(1)G(4)→(3)H(4), (3)H(6)→(3)H(5)} or {(1)G(4)→(3)H(5), (3)H(6)→(3)H(4)}] and {(3)H(4)→(3)F(4), (3)H(6)→(3)F(4)} cross-energy transfer. We found that the 1820.0 nm (3)F(4)→(3)H(6) luminescence intensity of Tm(0.08)Bi(0.01)Y(0.91)NbO(4) powder phosphor excited by 302.0 nm is 151 and 8.38 times larger, compared to Tm(0.005)Y(0.995)NbO(4) excited by 302.0 and 468.0 nm, in which the quantum cutting takes place between Tm(3+) ions and Bi(3+) ion only acts as sensitizer. To the knowledge of the authors, it is the first time that the effective Bi(3+) sensitized near-infrared quantum cutting of Tm(3+) ion activator has been reported. It can facilitate the probing of the next-generation environmentally friendly germanium solar cell.

12.
Opt Express ; 22(20): 23897-911, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25321967

RESUMO

Atomic ensembles are effective memory nodes for quantum communication network due to the long coherence time and the collective enhancement effect for the nonlinear interaction between an ensemble and a photon. Here we investigate the possibility of achieving the entanglement distillation for nonlocal atomic ensembles by the input-output process of a single photon as a result of cavity quantum electrodynamics. We give an optimal entanglement concentration protocol (ECP) for two-atomic-ensemble systems in a partially entangled pure state with known parameters and an efficient ECP for the systems in an unknown partially entangled pure state with a nondestructive parity-check detector (PCD). For the systems in a mixed entangled state, we introduce an entanglement purification protocol with PCDs. These entanglement distillation protocols have high fidelity and efficiency with current experimental techniques, and they are useful for quantum communication network with atomic-ensemble memories.

13.
Adv Mater ; 36(37): e2312948, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38813832

RESUMO

Colloidal quantum dots (QDs), as a class of 0D semiconductor materials, have generated widespread interest due to their adjustable band gap, exceptional color purity, near-unity quantum yield, and solution-processability. With decades of dedicated research, the potential applications of quantum dots have garnered significant recognition in both the academic and industrial communities. Furthermore, the related quantum dot light-emitting diodes (QLEDs) stand out as one of the most promising contenders for the next-generation display technologies. Although QD-based color conversion films are applied to improve the color gamut of existing display technologies, the broader application of QLED devices remains in its nascent stages, facing many challenges on the path to commercialization. This review encapsulates the historical discovery and subsequent research advancements in QD materials and their synthesis methods. Additionally, the working mechanisms and architectural design of QLED prototype devices are discussed. Furthermore, the review surveys the latest advancements of QLED devices within the display industry. The narrative concludes with an examination of the challenges and perspectives of QLED technology in the foreseeable future.

14.
Sci Data ; 11(1): 985, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256394

RESUMO

Accurately predicting ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) properties early in drug development is essential for selecting compounds with optimal pharmacokinetics and minimal toxicity. Existing ADMET-related benchmark sets are limited in utility due to their small dataset sizes and the lack of representation of compounds used in drug discovery projects. These shortcomings hinder their application in model building for drug discovery. To address this issue, we propose a multi-agent data mining system based on Large Language Models that effectively identifies experimental conditions within 14,401 bioassays. This approach facilitates merging entries from different sources, culminating in the creation of PharmaBench. Additionally, we have developed a data processing workflow to integrate data from various sources, resulting in 156,618 raw entries. Through this workflow, we constructed PharmaBench, a comprehensive benchmark set for ADMET properties, which comprises eleven ADMET datasets and 52,482 entries. This benchmark set is designed to serve as an open-source dataset for the development of AI models relevant to drug discovery projects.


Assuntos
Benchmarking , Descoberta de Drogas , Mineração de Dados , Farmacocinética , Preparações Farmacêuticas , Humanos
15.
Nat Commun ; 15(1): 5166, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886345

RESUMO

Boron-doped polycyclic aromatic hydrocarbons exhibit excellent optical properties, and regulating their photophysical processes is a powerful strategy to understand the luminescence mechanism and develop new materials and applications. Herein, an electrochemically responsive B-O dynamic coordination bond is proposed, and used to regulate the photophysical processes of boron-nitrogen-doped polyaromatic hydrocarbons. The formation of the B-O coordination bond under a suitable voltage is confirmed by experiments and theoretical calculations, and B-O coordination bond can be broken back to the initial state under opposite voltage. The whole process is accompanied by reversible changes in photophysical properties. Further, electrofluorochromic devices are successfully prepared based on the above electrochemically responsive coordination bond. The success and harvest of this exploration are beneficial to understand the luminescence mechanism of boron-nitrogen-doped polyaromatic hydrocarbons, and provide ideas for design of dynamic covalent bonds and broaden material types and applications.

16.
Aging Med (Milton) ; 7(4): 463-471, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39234198

RESUMO

Objectives: Patients undergoing a prior failed attempt of chronic total occlusion-percutaneous coronary intervention (CTO-PCI) represent a challenging subgroup across all patients undergoing CTO-PCI. There are limited data on the effects of a prior failed attempt on the outcomes of subsequent CTO-PCI. We aimed to compare the procedural results and 24-month outcomes of prior-failed-attempt CTO-PCI with those of initial-attempt CTO-PCI. Methods: Patients who underwent attempted CTO-PCI between January 2017 and December 2019 were prospectively enrolled. We analyzed the procedural results and 24-month major adverse cardiac events (MACE) between patients who underwent prior-failed-attempt and initial-attempt CTO-PCI. MACE was defined as a composite of cardiac death, target vessel-related myocardial infarction, and ischemia-driven target vessel revascularization (TVR) during follow-up. Results: In total, 484 patients who underwent CTO-PCI (prior-failed-attempt, n = 49; initial-attempt, n = 435) were enrolled during the study period. After propensity score matching (1:3), 147 patients were included in the initial-attempt group. The proportion of the Japanese-CTO (J-CTO) score ≥2 was higher in the patients who underwent prior failed attempt than in those who underwent initial attempt (77.5% vs. 38.8%, p < 0.001). The retrograde approach was more often adopted in the prior-failed-attempt group than in the initial-attempt group (32.7% vs. 3.4%, [P< 0.001). Successful CTO revascularization rates were significantly lower in the prior-failed attempt-group than in the initial attempt group (53.1% vs. 83.3%, P < 0.001). The multivariate analysis revealed that J-CTO score ≥2 [odds ratio (OR), 0.359; 95% confidence interval (CI), 0.159-0.812; P = 0.014], intravascular ultrasound procedure (OR, 4.640; 95% CI, 1.380-15.603; P = 0.013), and prior failed attempt (OR, 0.285; 95% CI, 0.125-0.648; P = 0.003) were the independent predictors for successful CTO revascularization. There were no significant differences in major procedural complications (2.0% vs. 0.7%, p = 0.438) and MACE rates (4.1% vs. 8.8%, p = 0.438) between the groups, mainly due to the TVR rate (4.1% vs. 8.2%, P = 0.522). Conclusions: Compared with initial-attempt CTO-PCI, prior-failed-attempt CTO-PCI deserves more attention, since it is associated with a lower successful CTO revascularization rate. Prior failed attempt, J-CTO score ≥2, and IVUS procedure are the determining factors for predicting successful CTO revascularization. There are no significantly different unfavorable outcomes between patients who undergo prior-failed-attempt and initial-attempt CTO-PCI.

17.
Int J Infect Dis ; 147: 107198, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39117174

RESUMO

OBJECTIVE: To investigate the effects of repeated vaccination with ancestral SARS-CoV-2 (Wuhan-hu-1)-based inactivated, recombinant protein subunit or vector-based vaccines on the neutralizing antibody response to Omicron subvariants. METHODS: Individuals who received four-dose vaccinations with the Wuhan-hu-1 strain, individuals who were infected with the BA.5 variant alone without prior vaccination, and individuals who experienced a BA.5 breakthrough infection (BTI) following receiving 2-4 doses of the Wuhan-hu-1 vaccine were enrolled. Neutralizing antibodies against D614G, BA.5, XBB.1.5, EG.5.1, and BA.2.86 were detected using a pseudovirus-based neutralization assay. Antigenic cartography was used to analyze cross-reactivity patterns among D614G, BA.5, XBB.1.5, EG.5.1, and BA.2.86 and sera from individuals. RESULTS: The highest neutralizing antibody titers against D614G were observed in individuals who only received four-dose vaccination and those who experienced BA.5 BTI, which was also significantly higher than the antibody titers against XBB.1.5, EG.5.1, and BA.2.86. In contrast, only BA.5 infection elicited comparable neutralizing antibody titers against the tested variants. While neutralizing antibody titers against D614G or BA.5 were similar across the cohorts, the neutralizing capacity of antibodies against XBB.1.5, EG.5.1, and BA.2.86 was significantly reduced. BA.5 BTI following heterologous booster induced significantly higher neutralizing antibody titers against the variants, particularly against XBB.1.5 and EG.5.1, than uninfected vaccinated individuals, only BA.5 infected individuals, or those with BA.5 BTI after primary vaccination. CONCLUSIONS: Our findings suggest that repeated vaccination with the Wuhan-hu-1 strain imprinted a neutralizing antibody response toward the Wuhan-hu-1 strain with limited effects on the antibody response to the Omicron subvariants.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , SARS-CoV-2/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , COVID-19/imunologia , COVID-19/prevenção & controle , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Adulto , Feminino , Masculino , Pessoa de Meia-Idade , Vacinação , Glicoproteína da Espícula de Coronavírus/imunologia , Imunização Secundária , Reações Cruzadas/imunologia , Testes de Neutralização
18.
Cell Rep ; 43(7): 114387, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38896777

RESUMO

The ongoing emergence of SARS-CoV-2 variants poses challenges to the immunity induced by infections and vaccination. We conduct a 6-month longitudinal evaluation of antibody binding and neutralization of sera from individuals with six different combinations of vaccination and infection against BA.5, XBB.1.5, EG.5.1, and BA.2.86. We find that most individuals produce spike-binding IgG or neutralizing antibodies against BA.5, XBB.1.5, EG.5.1, and BA.2.86 2 months after infection or vaccination. However, compared to ancestral strain and BA.5 variant, XBB.1.5, EG.5.1, and BA.2.86 exhibit comparable but significant immune evasion. The spike-binding IgG and neutralizing antibody titers decrease in individuals without additional antigen exposure, and <50% of individuals neutralize XBB.1.5, EG.5.1, and BA.2.86 during the 6-month follow-up. Approximately 57% of the 107 followed up individuals experienced an additional infection, leading to improved binding IgG and neutralizing antibody levels against these variants. These findings provide insights into the impact of SARS-CoV-2 variants on immunity following repeated exposure.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunoglobulina G , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinação , Humanos , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Vacinas contra COVID-19/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Glicoproteína da Espícula de Coronavírus/imunologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Formação de Anticorpos/imunologia
19.
Opt Express ; 21(9): 11457-64, 2013 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-23670002

RESUMO

We experimentally demonstrate and characterize an organic octagonal quasicrystal slab with a single-defect microcavity at low-index contrast. The gain medium is the conjugated-polymer, composed by two PPV derivatives, a BEHP-PPV and a MEH-PPV. By optical pumping, the lasing action is achieved at 607 nm with a FWHM of 1 nm. The threshold of lasing is 9 µJ/cm(2). The intensity of the lasing peak depends linearly on the pump energy above the threshold.


Assuntos
Lasers de Estado Sólido , Compostos Orgânicos/química , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização
20.
Opt Express ; 21 Suppl 5: A829-40, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24104578

RESUMO

In the present study, the multiphoton near-infrared downconversion quantum cutting luminescence phenomena of Tm3+ ion in (Y(1-x)Tm(x))(3)Al(5)O(12) powder phosphor, which is currently a hot research topic throughout the world, is reported. The x-ray diffraction spectra, the visible to near-infrared excitation and emission spectra, and fluorescence lifetimes are measured. It is found that Tm:YAG powder phosphor has intense two-photon quantum cutting luminescence, and, for the first time, it is found that Tm:YAG powder phosphor has strong four-photon near-infrared quantum cutting luminescence of 1788 nm (3)F4 → (3)H6 fluorescence of Tm(3+) ion. It is also found that the theoretical up-limit of four-photon near-infrared quantum cutting efficiency is about 282.12%, which results from both the {(1)D2 → (3)F2, (3)H6 → (3)H4} and {(3)H4 → (3)F4, (3)H6 → (3)F4} cross-energy transfers.


Assuntos
Medições Luminescentes/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Túlio/química , Teste de Materiais , Pós , Teoria Quântica
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