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1.
Light Sci Appl ; 13(1): 74, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38485915

RESUMEN

Photonic quantum computation plays an important role and offers unique advantages. Two decades after the milestone work of Knill-Laflamme-Milburn, various architectures of photonic processors have been proposed, and quantum advantage over classical computers has also been demonstrated. It is now the opportune time to apply this technology to real-world applications. However, at current technology level, this aim is restricted by either programmability in bulk optics or loss in integrated optics for the existing architectures of processors, for which the resource cost is also a problem. Here we present a von-Neumann-like architecture based on temporal-mode encoding and looped structure on table, which is capable of multimode-universal programmability, resource-efficiency, phase-stability and software-scalability. In order to illustrate these merits, we execute two different programs with varying resource requirements on the same processor, to investigate quantum signature of chaos from two aspects: the signature behaviors exhibited in phase space (13 modes), and the Fermi golden rule which has not been experimentally studied in quantitative way before (26 modes). The maximal program contains an optical interferometer network with 1694 freely-adjustable phases. Considering current state-of-the-art, our architecture stands as the most promising candidate for real-world applications.

2.
Waste Manag ; 174: 320-327, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38091656

RESUMEN

Disposal of automobile shredder residue (ASR) via pyrolysis enables the recovery of valuable products; however, the production of hazardous pollutants and low-value products is inevitable due to its high chlorine content. In this work, chlorine evolution behavior and the conversion mechanism during ASR pyrolysis between 480 and 600 °C were systematically studied. The experimental results for organic chlorine (Org-Cl) showed that released chlorinated gases were complex, and HCl only accounted for 35% of the gas phase products, while short-chain hydrocarbons with carbon atoms between two and four accounted for 52%. Chlorine was predominantly retained in the char, and Org-Cl was the primary contributor to the residual chlorine, accounting for over 50% of the char. The content of inorganic chlorine (InO-Cl) was low in the raw sample but significantly increased in the char. Through the distinction between organic and inorganic chlorine content in char, it was confirmed that Org-Cl could be converted to InO-Cl due to complex secondary reactions with metallic compounds. The conversion was favored by increasing the Org-Cl content and the temperature. Our findings clarified the evolution mechanism of chlorine and the transformation from Org-Cl to InO-Cl, thus providing guidance for chlorine regulation and the efficient recycling of metal resources.


Asunto(s)
Automóviles , Cloro , Pirólisis , Reciclaje , Metales , Gases/química
3.
Int J Surg Case Rep ; 114: 109128, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38091707

RESUMEN

INTRODUCTION: Aspergillus endocarditis is a rare fungal infection associated with a poor prognosis. Most cases of Aspergillus endocarditis involve prosthetic valves, with native valve involvement being rarely reported. CASE PRESENTATION: A 53-year-old asian female patient presented with fever, chills, dyspnea, generalized fatigue, and significant weight loss one month after undergoing left lower lobectomy for a pulmonary abscess. Echocardiogram showed a large mobile vegetation with a broad base on the anterior leaflet of the mitral valve, resembling atrial myxoma. Despite negative blood cultures, circulating DNA of Aspergillus fumigatus was detected by metagenome Next Generation Sequencing, prompting the initiation of empiric antifungal therapy with voriconazole. Emergency surgery, involving thorough debridement and mitral valve replacement, was successfully performed. Indefinite fungal suppression therapy with oral voriconazole is continued to mitigate the risk of recurrence. The patient survived with no signs of Aspergillus disease recurrence for four years. CLINICAL DISCUSSION: Diagnosis of Aspergillus endocarditis requires a high index of suspicion and is often delayed due to consistently negative results from blood cultures. Non-culture-based methods, particularly metagenome Next-Generation Sequencing, play a crucial role in early diagnosis and therapeutic decision-making. Surgical debridement and valve replacement are imperative for survival in cases of Aspergillus endocarditis. Voriconazole should be considered the primary fungicidal agent for its treatment. Moreover, lifelong fungal suppression therapy is strongly recommended for all survivors to ensure long-term survival and minimize the risk of recurrence. CONCLUSION: Despite grim prognosis associated with Aspergillus endocarditis, patients can attain long-term survival through meticulous surgical debridement and lifelong antifungal therapy.

4.
Clin Chim Acta ; 552: 117698, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38072301

RESUMEN

BACKGROUND: Infective endocarditis is a life-threatening uncommon infectious disease, and we aimed to explore the clinical utility of venous or arterial blood-based metagenomic next-generation sequencing (mNGS) approaches to diagnose left-sided infective endocarditis (LSIE). METHODS: We prospectively studied 79 LSIE patients who received valvular surgery in our hospital. Results of blood culture, valve culture, venous blood-based mNGS, arterial blood-based mNGS, venous blood-based mNGS plus blood culture, and arterial blood-based mNGS plus blood culture were evaluated and compared. RESULTS: Both venous blood- and arterial blood-based mNGS methods displayed significantly higher positive detection rates than blood culture and valve culture (43.0 %, 49.4 % vs. 32.9 %, 19.0 %; P < 0.001). Strikingly, when combining blood-based mNGS and blood culture, the positive rate could be further improved to more than 60 %. Moreover, we found mNGS LSIE detection was closely associated with preoperative leukocyte (P = 0.027), neutrophil value (P = 0.018), vegetation ≥ 14 mm (P = 0.043), and vegetations in aortic valve (P = 0.048). In addition, we discovered that blood-based mNGS had a superir capacity over blood culture to detect gram-negative bacteria, fungi, Bartonella Quintana, and mixed infections than blood culture. CONCLUSION: This study indicates that venous blood- and arterial blood-based mNGS displayed high positive rate in the rapid detection of pathogens in high-risk LSIE patients.


Asunto(s)
Endocarditis , Venas , Humanos , Estudios Prospectivos , Endocarditis/diagnóstico , Leucocitos , Secuenciación de Nucleótidos de Alto Rendimiento , Sensibilidad y Especificidad
5.
Artículo en Inglés | MEDLINE | ID: mdl-38092988

RESUMEN

Extracellular vesicles (EVs) derived from mouse bone marrow mesenchymal stem cells (mBMSCs) convey the CAV1 protein, influencing the TGF-ß1/SMAD2/c-JUN pathway and thus the molecular mechanisms underlying myocardial fibrosis (MF) post-myocardial infarction (MI). Through various experimental methods, including transmission electron microscopy, Nanosight analysis, Western blot, ELISA, and qRT-PCR, we isolated, purified, and identified EVs originating from mBMSCs. Bioinformatics and experimental findings show a reduced expression of CAV1 in myocardial fibrosis tissue. Furthermore, our findings suggest that mBMSC-EVs can deliver CAV1 to cardiac fibroblasts (CFs) and that silencing CAV1 in mBMSC-EVs promotes CF fibrosis. In vivo studies further corroborated these findings. In conclusion, mBMSC-EVs mitigate myocardial fibrosis in MI mice by delivering the CAV1 protein, inhibiting the TGF-ß1/SMAD2/c-JUN pathway. Molecular mechanism of mBMSC-EVs-CAV1-mediated TGF-ß1/SMAD2/c-JUN axis in inhibiting cardiac fibroblast differentiation to improve MF after MI. mBMSC-EVs deliver CAV1 protein to CFs where the protein expression of CAV1 is upregulated upon hypoxia conditions. The TGF-ß1/SMAD2 signaling pathway downstream of CAV1 is consequently inactivated, the transcription of c-JUN is inhibited, and transcription of SMAD2/c-JUN transcription complex target genes α-SMA and Collagen I is reduced. By this mechanism, CF fibrosis and apoptosis are suppressed in vitro and MF is ameliorated in MI mice.

6.
Acta Pharm Sin B ; 13(11): 4578-4590, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37969732

RESUMEN

Biliary atresia is a rare infant disease that predisposes patients to liver transplantation and death if not treated in time. However, early diagnosis is challenging because the clinical manifestations and laboratory tests of biliary atresia overlap with other cholestatic diseases. Therefore, it is very important to develop a simple, safe and reliable method for the early diagnosis of biliary atresia. Herein, a novel NIR-II fluorescence probe, HZL2, with high quantum yield, excellent biocompatibility, low cytotoxicity and rapid excretion through the liver and gallbladder was developed based on the oil/water partition coefficient and permeability. A simple fecal sample after injection of HZL2 can be used to efficiently identify the success of the mouse model of biliary atresia for the first time, allowing for an early diagnosis of the disease. This study not only developed a simple and safe method for the early diagnosis of biliary atresia with great potential in clinical translation but also provides a research tool for the development of pathogenesis and therapeutic medicines for biliary atresia.

7.
Geohealth ; 7(10): e2023GH000887, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37885913

RESUMEN

The increasing prevalence of warmer trends and climate extremes exacerbate the population's exposure to urban settlements. This work investigated population exposure changes to mean and extreme climate events in different Agro-Ecological Zones (AEZs) of Pakistan and associated mechanisms (1979-2020). Spatiotemporal trends in mean and extreme temperatures revealed significant warming mainly over northern, northeastern, and southern AEZs. In contrast, mean-to-extreme precipitation changes showed non-uniform patterns with a significant increase in the northeast AEZs. Population exposure to mean (extreme) temperature and precipitation events increased two-fold during 2000-2020. The AEZs in urban settlements (i.e., Indus Delta, Northern Irrigated Plain, and Barani/Rainfall) show a maximum exposure to extreme temperatures of about 70-100 × 106 (person-days) in the reference period (1979-1999), which increases to 140-200 × 106 person-days in the recent period (2000-2020). In addition, the highest exposure to extreme precipitation days also increases to 40-200 × 106 person-days during 2000-2020 than 1979-1999 (20-100 × 106) person-days. Relative changes in exposure are large (60%-90%) for the AEZs across northeast Pakistan, justifying the spatial population patterns over these zones. Overall, the observed changes in exposure are primarily attributed to the climate effect (50%) over most AEZs except Northern Irrigated Plain for R10 and R20 events, where the interaction effect takes the lead. The population exposure rapidly increased over major AEZs of Pakistan, which could be more vulnerable to extreme events due to rapid urbanization and population growth in the near future.

8.
Nanoscale ; 15(36): 15000-15007, 2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37665054

RESUMEN

Among the various kinds of spin defects in hexagonal boron nitride (hBN), the negatively charged boron vacancy (VB-) spin defect that can be site-specifically generated is undoubtedly a potential candidate for quantum sensing, but its low quantum efficiency restricts its practical applications. Here, we demonstrate a robust enhancement structure called reflective dielectric cavity (RDC) with advantages including easy on-chip integration, convenient processing, low cost and suitable broad-spectrum enhancement for VB- defects. In the experiment, we used a metal reflective layer under the hBN flakes, filled with a transition dielectric layer in the middle, and adjusted the thickness of the dielectric layer to achieve the best coupling between RDC and spin defects in hBN. A remarkable 11-fold enhancement in the fluorescence intensity of VB- spin defects in hBN flakes can be achieved. By designing the metal layer into a waveguide structure, high-contrast optically detected magnetic resonance (ODMR) signal (∼21%) can be obtained. The oxide layer of the RDC can be used as the integrated material to implement secondary processing of micro-nano photonic devices, which means that it can be combined with other enhancement structures to achieve stronger enhancement. This work has guiding significance for realizing the on-chip integration of spin defects in two-dimensional materials.

9.
Langmuir ; 39(29): 10189-10198, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37432677

RESUMEN

Electrowetting-on-dielectric (EWOD) technology has been considered as a promising candidate for digital microfluidic (DMF) applications due to its outstanding flexibility and integrability. The dielectric layer with a hydrophobic surface is the key element of an EWOD device, determining its driving voltage, reliability, and lifetime. Hereby, inspired by the ionic-liquid-filled structuring polymer with high capacitance independent on thickness, namely ion gel (IG), we develop a polymer (P)-ion gel-amorphous fluoropolymer, namely, PIGAF, composite film as a replaceable hydrophobic dielectric layer for fabrication of a high-efficiency and stable EWOD-DMF device at relatively low voltage. The results show that the proposed EWOD devices using the PIGAF-based dielectric layer can achieve a large contact angle (θ) change of ∼50° and excellent reversibility with a contact angle hysteresis of ≤5° at a relatively low voltage of 30 Vrms. More importantly, the EWOD actuation voltage did not change obviously with the PIGAF film thickness in the range of several to tens of microns, enabling the thickness of the film to be adjusted according to the demand within a certain range while keeping the actuation voltage low. An EWOD-DMF device can be prepared by simply stacking a PIGAF film onto a PCB board, demonstrating stable droplet actuation (motion) at 30 Vrms and 1 kHz as well as a maximum moving velocity of 69 mm/s at 140 Vrms and 1 kHz. The PIGAF film was highly stable and reliable, maintaining excellent EWOD performance after multiple droplet manipulations (≥50 cycles) or long-term storage of 1 year. The proposed EWOD-DMF device has been demonstrated for digital chemical reactions and biomedical sensing applications.

10.
Front Psychol ; 14: 1170656, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37228337

RESUMEN

This research examined the relationships between students' academic performance and their social and emotional skills in China, as well as the mediation pathways from the perspective of connectedness and social cognitive theory. A sample of 5,703 fourth to sixth graders from less affluent areas was investigated in a large-scale survey. The results indicated that students' academic performance had salient positive connections with their socio-emotional skills. Structural equation modeling results revealed that both students' perception of themselves (self-efficacy) and their relation with key persons (teacher-student relationship) played mediated roles in the association between academic achievement and social and emotional skills with the indirect path accounting for 66.66% of the total effect. This study highlights the important role of socioemotional skills in academic performance and suggests the need for further research to develop effective strategies and interventions for socioemotional development in Chinese students.

11.
Nat Commun ; 14(1): 2893, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37210408

RESUMEN

Hexagonal boron nitride (hBN) is a remarkable two-dimensional (2D) material that hosts solid-state spins and has great potential to be used in quantum information applications, including quantum networks. However, in this application, both the optical and spin properties are crucial for single spins but have not yet been discovered simultaneously for hBN spins. Here, we realize an efficient method for arraying and isolating the single defects of hBN and use this method to discover a new spin defect with a high probability of 85%. This single defect exhibits outstanding optical properties and an optically controllable spin, as indicated by the observed significant Rabi oscillation and Hahn echo experiments at room temperature. First principles calculations indicate that complexes of carbon and oxygen dopants may be the origin of the single spin defects. This provides a possibility for further addressing spins that can be optically controlled.

12.
Biol Psychol ; 179: 108565, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37062354

RESUMEN

The relationship between number and space is an important issue in numerical cognition. The spatial-numerical association of response codes (SNARC) effect is a classic example of the association between numbers and spaces. It refers to the phenomenon whereby left-handed responses occur faster to small number and right-handed responses occur faster to large number. The current study explored the shared and distinct neural correlates of the SNARC effect considering numbers in eye and numbers in mind, by using event-related potentials (ERPs) technology. In each trial of the task, participants were asked to press freely one of two keys as a response to a number presented visually (numbers in eye) or via imagination (numbers in mind). The behavioral results indicated that the free-choice key presses were affected by the magnitudes of the numbers either in eye or in mind. Electrophysiological results observed that the SNARC effect appeared only in the 110-140 ms time window for numbers in eye. In contrast, for numbers in mind, the SNARC effect appeared during a longer time window (110-330 ms). These results suggest that both, numbers in eye and numbers in mind, can induce spatial bias at the early stimulus-representation stage, but the time duration of the spatial bias is longer for numbers in mind than numbers in eye. This may reflect a closer connection between numbers in mind and mental number line.


Asunto(s)
Cognición , Percepción Espacial , Humanos , Tiempo de Reacción/fisiología , Percepción Espacial/fisiología , Cognición/fisiología , Imaginación , Potenciales Evocados
13.
Opt Lett ; 48(3): 731-734, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723575

RESUMEN

A scheme to investigate nonlocal effects in metal using the coupling between localized graphene plasmons (GPs) and acoustic plasmons (APs) is proposed. Because of the extremely strong field confinement property, the APs on a configuration consisting of monolayer graphene and a metal film have different dispersions when the nonlocal response is considered or not. A graphene nanoribbon array can efficiently couple incident light to the localized GPs on the ribbons and subsequently the APs. The strong coupling between the two kinds of plasmon, equivalent to electric field dipole interaction, is highly related to the acoustic plasmonic dispersion and induces different absorption spectra, depending on the dispersion. Using a very simple model, nonlocal effects can be extracted from the spectra. The investigation provides a promising platform to manipulate nanophotonics and study nonlocal effects.

14.
Biology (Basel) ; 11(12)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36552203

RESUMEN

Terrestrial net primary production (NPP) is a key carbon flux that changes with rising atmospheric CO2 and CO2-induced climate change. Earth system models are commonly used to investigate these NPP changes because of their fundamentally trustworthy ability to simulate physical climate systems and terrestrial biogeochemical processes. However, many uncertainties remain in projecting NPP responses, due to their complex processes and divergent model characteristics. This study estimated NPP responses to elevated CO2 and CO2-induced climate change using the Chinese Academy of Sciences Earth System Model version 2 (CAS-ESM2), as well as 22 CMIP6 models. Based on CMIP6 pre-industrial and abruptly quadrupled CO2 experiments, the analysis focused on a comparison of the CAS-ESM2 with the multi-model ensemble (MME), and on a detection of underlying causes of their differences. We found that all of the models showed an overall enhancement in NPP, and that CAS-ESM2 projected a slightly weaker NPP enhancement than MME. This weaker NPP enhancement was the net result of much weaker NPP enhancement over the tropics, and a little stronger NPP enhancement over northern high latitudes. We further report that these differences in NPP responses between the CAS-ESM2 and MME resulted from their different behaviors in simulating NPP trends with modeling time, and are attributed to their different projections of CO2-induced climatic anomalies and different climate sensitivities. These results are favorable for understanding and further improving the performance of the CAS-ESM2 in projecting the terrestrial carbon cycle, and point towards a need for greater understanding and improvements for both physical climatic processes and the terrestrial carbon cycle.

15.
Ying Yong Sheng Tai Xue Bao ; 33(3): 638-647, 2022 Mar.
Artículo en Chino | MEDLINE | ID: mdl-35524514

RESUMEN

Multiple ecosystems (grassland, desert and shrubs) always coexist in ecologically fragile areas. Influence by external environmental conditions and human activities, one ecosystem in ecologically fragile areas would be changed into another, called abrupt change. It is important to analyze the stability of each ecosystem in ecologically fragile areas under the condition of multiple ecosystems coexistence for understanding ecosystem changes. In this article, we reviewed several mathematical models that can describe the dynamic system and stability of multiple ecosystems in ecologically fragile areas. The dynamic system described by differential equations included the uniform and non-uniform ecosystems, as well as multi-ecosystems with the existence of forests, grasses, and deserts. There were three types of methods for analyzing the stability of the ecosystem. One type was the analysis method of ecosystem stability caused by the initial perturbation that could represent human activities, and the other type was the analysis method of ecosystem stability caused by the model perturbation that can represent the changes of environmental factors (precipitation, temperature, etc.), and the third type was the analysis method of ecosystem stability caused by the combination of initial perturbation and model perturbation. Finally, we introduced how to analyze the stabilities of ecosystem in ecologically fragile areas with those methods. These mathematical methods not only help us understand the stability of the ecosystems in the ecologically fragile area, but also provide theoretical guidance for the abrupt change of the ecological system, future prediction, and management.


Asunto(s)
Ecosistema , Bosques , Actividades Humanas , Humanos , Modelos Teóricos , Poaceae
16.
Front Cardiovasc Med ; 9: 811492, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35369282

RESUMEN

Objective: The present study aimed to prospectively evaluate the role of metagenomic next-generation sequencing (mNGS) in the etiological diagnosis of patients with perioperative infective endocarditis (IE). Methods: From May 1st, 2019 to December 31st, 2020, a total of 99 patients with IE were enrolled in the present study according to the modified Duke criteria, etiological, and pathological results. 11 non-IE patients undergoing heart valve surgery in the same period were selected as the control group. A blood culture test was performed immediately after admission, and the valves harvested operatively were examined by blood culture and mNGS. Results: In the IE group, there were 29 cases (29.3%) with positive blood culture, 16 cases (16.2%) with positive valve culture, and 85 cases (85.9%) with positive valve mNGS. Compared to culture-based detection, mNGS achieved better performance with a sensitivity, specificity, area under the curve (AUC) of 0.859, 0.727, and 0.793, respectively. The combined approach using culture and mNGS further improved the diagnostic accuracy (sensitivity 89.9%, specificity 72.7%, AUC 0.813). Preoperative white blood cell (P = 0.029) and neutrophils (P = 0.046) were identified as independent factors affecting the detection rate of mNGS. In the mNGS-positive group, 95 strains of pathogens were found and 10 cases were identified with mixed infection. There were 72 gram-positive bacteria and 14 gram-negative bacteria. mNGS positive group displayed higher species richness than mNGS negative group with enrichment of Streptococcus sanguis, Streptococcus buccalis, and Streptococcus griseus. Proteobacteria and Actinomycetes were enriched in mNGS negative group. Notably, six patients showed disconcordant results between culture and mNGS. Rothia aeria was identified in the blood culture, valve culture, and valve mNGS in one patient. Bartonella Quintana and Coxiella burnetii, which were fastidious intracellular bacteria, were found in two blood and valve culture-negative cases. Conclusions: mNGS outperformed the conventional culture method and displayed high accuracy in detecting pathogens in IE patients. This study provided support for the use of mNGS in the etiological diagnosis of IE.

17.
Nat Commun ; 13(1): 758, 2022 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-35140208

RESUMEN

Immunotherapy with immune checkpoint blockade (ICB) has shown limited benefits in hepatocellular carcinoma (HCC) and other cancers, mediated in part by the immunosuppressive tumor microenvironment (TME). As p53 loss of function may play a role in immunosuppression, we herein examine the effects of restoring p53 expression on the immune TME and ICB efficacy. We develop and optimize a CXCR4-targeted mRNA nanoparticle platform to effectively induce p53 expression in HCC models. Using p53-null orthotopic and ectopic models of murine HCC, we find that combining CXCR4-targeted p53 mRNA nanoparticles with anti-PD-1 therapy effectively induces global reprogramming of cellular and molecular components of the immune TME. This effect results in improved anti-tumor effects compared to anti-PD-1 therapy or therapeutic p53 expression alone. Thus, our findings demonstrate the reversal of immunosuppression in HCC by a p53 mRNA nanomedicine when combined with ICB and support the implementation of this strategy for cancer treatment.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , ARN Mensajero/farmacología , Microambiente Tumoral/inmunología , Proteína p53 Supresora de Tumor , Animales , Carcinoma Hepatocelular/inmunología , Línea Celular Tumoral , Femenino , Humanos , Inhibidores de Puntos de Control Inmunológico/inmunología , Terapia de Inmunosupresión , Inmunoterapia/métodos , Neoplasias Hepáticas/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Nanomedicina , Receptores CXCR4/genética , Proteína p53 Supresora de Tumor/inmunología
18.
ACS Omega ; 7(2): 1733-1739, 2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35071868

RESUMEN

Optically addressable spin defects in wide-band-gap semiconductors as promising systems for quantum information and sensing applications have recently attracted increased attention. Spin defects in two-dimensional materials are expected to show superiority in quantum sensing due to their atomic thickness. Here, we demonstrate that an ensemble of negatively charged boron vacancies (VB -) with good spin properties in hexagonal boron nitride (hBN) can be generated by ion implantation. We carry out optically detected magnetic resonance measurements at room temperature to characterize the spin properties of ensembles of VB - defects, showing a zero-field splitting frequency of ∼3.47 GHz. We compare the photoluminescence intensity and spin properties of VB - defects generated using different implantation parameters, such as fluence, energy, and ion species. With the use of the proper parameters, we can successfully create VB - defects with a high probability. Our results provide a simple and practicable method to create spin defects in hBN, which is of great significance for realizing integrated hBN-based devices.

19.
Appl Opt ; 60(16): 4871-4877, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34143048

RESUMEN

In this paper, we propose a radio-over-fiber system with no filters and generate 80 and 160 GHz millimeter (mm) waves via two Mach-Zehnder modulators (MZMs). The two MZMs, biased at the maximum transmission point, are used to suppress odd-order sidebands. By controlling the phase difference between the RF driving signal of the two MZMs, the $\pm({4}{n - 2})$-order is canceled. By adjusting the optical attenuator and phase shifter, the 0-order sideband is canceled, so only the $\pm 4{n}$-order sidebands are left. The simulation results show that using a 10 GHz RF signal to drive the MZMs, we obtain an 80 GHz mm wave signal with a 36.59 dB optical sideband suppression ratio (OSSR), a 30.27 dB radio frequency sideband suppression ratio (RFSSR), and a 160 GHz mm wave signal with a 30.34 dB OSSR and 24.77 dB RFSSR. The results are consistent with the theoretical analysis. Because no optical filter is employed and only two MZMs are used, the system exhibits a simple structure, good performance and is low cost.

20.
ACS Omega ; 6(13): 9196-9203, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33842788

RESUMEN

Transient receptor potential canonical channel 6 (TRPC6) has been implicated in many kinds of malignant tumors, but very few potent TRPC6 antagonists are available. In this study, a benzothiazole amide derivative 1a was discovered as a TRPC6 activator in a cell-based high-throughput screening. A series of benzothiazole amide derivatives were designed and synthesized. The docking analyses indicated that the conformations of the compounds bound to TRPC6 determined the agonistic or antagonistic activity of the compounds against TRPC6, and compound 1s with the tetrahydronaphthalene group in R1 position fit well into the binding pocket of the antagonist-bound conformation of TRPC6. Compound 1s showed an inhibitory potency order of TRPC3 (IC50 3.3 ± 0.13 µM) ≈ C6 (IC50 4.2 ± 0.1 µM) > C7 with good anti-gastric cancer activity in a micromolecular range against AGS and MKN-45, respectively. In addition, 1s inhibited the invasion and migration of MKN-45 cells in vitro.

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