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1.
Nanotechnology ; 35(4)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37669634

RESUMO

Two-dimensional transition metal dichalcogenides (TMDs), as flexible and stretchable materials, have attracted considerable attention in the field of novel flexible electronics due to their excellent mechanical, optical, and electronic properties. Among the various TMD materials, atomically thin MoS2has become the most widely used material due to its advantageous properties, such as its adjustable bandgap, excellent performance, and ease of preparation. In this work, we demonstrated the practicality of a stacked wafer-scale two-layer MoS2film obtained by transferring multiple single-layer films grown using chemical vapor deposition. The MoS2field-effect transistor cell had a top-gated device structure with a (PI) film as the substrate, which exhibited a high on/off ratio (108), large average mobility (∼8.56 cm2V-1s-1), and exceptional uniformity. Furthermore, a range of flexible integrated logic devices, including inverters, NOR gates, and NAND gates, were successfully implemented via traditional lithography. These results highlight the immense potential of TMD materials, particularly MoS2, in enabling advanced flexible electronic and optoelectronic devices, which pave the way for transformative applications in future-generation electronics.

2.
J Clin Lab Anal ; 36(1): e24099, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34788474

RESUMO

BACKGROUND: Lysophosphatidylcholine (LPC) plays pivotal roles in several physiological processes and their disturbances are closely associated with various disorders. In this study, we described the development and validation of a reliable and simple flow injection analysis-tandem mass spectrometry (FIA-MS/MS)-based method using dried blood spots (DBS) for quantification of four individual LPC (C20:0, C22:0, C24:0, and C26:0). METHODS: Lysophosphatidylcholines were extracted from 3.2 mm DBS with 85% methanol containing 60 ng/ml internal standard using a rapid (30 min) and simple procedure. The analytes and the internal standard were directly measured by triple quadrupole tandem mass spectrometry in multiple reactions monitoring mode via positive electrospray ionization. RESULTS: Method validation results showed good linearity ranging from 50 to 2000 ng/ml for each LPC. Intra- and inter-day precision and accuracy were within the acceptable limits at four quality control levels. Recovery was from 70.5% to 107.0%, and all analytes in DBS were stable under assay conditions (24 h at room temperature and 72 h in autosampler). The validated method was successfully applied to assessment of C20:0-C26:0LPCs in 1900 Chinese neonates. C26:0-LPC levels in this study were consistent with previously published values. CONCLUSION: We propose a simple FIA-MS/MS method for analyzing C20:0-C26:0LPCs in DBS, which can be used for first-tier screening.


Assuntos
Teste em Amostras de Sangue Seco/métodos , Análise de Injeção de Fluxo/métodos , Lisofosfatidilcolinas/sangue , Triagem Neonatal/métodos , Espectrometria de Massas em Tandem/métodos , Humanos , Recém-Nascido , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Echocardiography ; 39(5): 658-666, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35347747

RESUMO

BACKGROUND: Accurate, reproducible, noninvasive determination of left ventricular (LV) volumes and ejection fraction (EF) is important for clinical assessment, selection of therapy, and serial monitoring of patients with hypertrophic cardiomyopathy (HCM). Current clinical Two-dimensional echocardiography (2DE) may cause inaccurate measurements in patients with HCM because of their asymmetric ventricles and limitations of 2DE technology. Three-dimensional echocardiography (3DE) have demonstrated significantly greater accuracy. However, the time-consuming workflow limits the clinical utility of 3DE. AIM: We aim to compare the performance of a novel automated 3DE system (HeartModel, Philips Healthcare) with 2DE in a group of patients with HCM. Cardiac magnetic resonance (CMR) was reference standard. METHODS: Fifty-three patients with HCM were examined by automated 3DE (3DEA), two-dimensional biplane Simpson's method (2DBP), manual 3DE method, and CMR, respectively. For patients with poor automated quantification, manual correction was performed. The Pearson correlation coefficient and Bland-Altman analysis and paired Student t tests were used to assess inter-technique agreement. RESULTS: 3DEA measurements with contour editing correlate well with CMR and manual 2DE and 3DE measurements (r = .80-.96). The analysis time of 3DEA was shorter than that of 2DBP (3DEA, 141 ± 15s; 2DBP, 174 ± 17 s). Inter-observer variability was reduced significantly with use of 3DEA. CONCLUSION: Compared with current clinical 2DBP method, the analysis time of automated 3DE was much shorter with the added benefit of enhanced accuracy and reproducibility. Patients with asymmetric chamber may rely more on the timesaving automated 3DE quantification in the future.


Assuntos
Cardiomiopatia Hipertrófica , Ecocardiografia Tridimensional , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ecocardiografia/métodos , Ecocardiografia Tridimensional/métodos , Ventrículos do Coração , Humanos , Reprodutibilidade dos Testes , Volume Sistólico , Função Ventricular Esquerda
4.
Fetal Pediatr Pathol ; 41(3): 443-450, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33198547

RESUMO

Background: Phenylalanine-restricted diets have been the basis of therapy for phenylketonuria; however, little is known how this treatment effects homeostasis of other amino acids. This study aimed to assess blood amino acid alterations in phenylketonuric neonates before and after treatment to identify any residual amino acid alterations with phenylalanine restriction in these treated children. Methods: Concentrations of 11 amino acids were measured using liquid chromatography-tandem mass spectrometry performed on dried blood spots. Results: Elevated blood phenylalanine, arginine, citrulline, valine, methionine concentrations and decreased tyrosine, proline concentrations were observed in phenylketonuria neonates relative to controls, of which phenylalanine, arginine, methionine, tyrosine, and proline levels could be either partially or completely restored with dietary intervention, whereas citrulline and valine were not restored and remained higher. Conclusions: Blood amino acid homeostasis is disrupted in phenylketonuria. Although dietary intervention adjusts amino acid homeostasis in the direction of a healthy equilibrium, complete restoration is not achieved.


Assuntos
Fenilalanina , Fenilcetonúrias , Arginina , Benchmarking , Criança , Pré-Escolar , Citrulina , Dieta , Humanos , Recém-Nascido , Metionina , Fenilcetonúrias/metabolismo , Prolina , Tirosina , Valina
5.
J Clin Lab Anal ; 35(3): e23658, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33219583

RESUMO

BACKGROUND: To study the prevalence of the exposure of pregnant women to antimicrobials, a sensitive and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to determine nine antimicrobials, namely sulfadimidine, sulfapyridine, sulfadiazine, sulfathiazole, ofloxacin, ciprofloxacin, norfloxacin, tetracycline, and lincomycin, in human serum. METHODS: The sample preparation procedure included protein precipitation followed by a cleanup step with solid phase extraction (SPE). Separation was carried out using a CORTECS T3 column (100 × 2.1 mm, 2.7 µm) by gradient elution with a runtime of 8.0 min. Detection was performed on a triple quadruple tandem mass spectrometer with scheduled multiple reaction monitoring (sMRM) in positive ion scan mode. RESULTS: The calibration curves were linear over the concentration range of 0.5-50 ng/ml, and the limit of quantitation was between 0.01 and 0.2 ng/ml. For each level of quality control samples, the inter- and intra-assay precision values were less than 12.0%, and the accuracy ranged from 86.1% to 109.0%. No significant matrix effect or carryover was observed. The antimicrobials of interest were stable under all investigated conditions. The validated method was applied to analyze clinical samples from pregnant women in China, and 10 out of 500 samples showed the presence of antimicrobial residues. Moreover, compared with the time-resolved fluoro-immunoassay (TRFIA) method, the developed method showed greater sensitivity and specificity. CONCLUSION: This study provides a simple and rapid LC-MS/MS method for the simultaneous measurement of nine antimicrobials in serum samples, which could be a useful tool in clinical utilization.


Assuntos
Anti-Infecciosos/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Adolescente , Adulto , Calibragem , Feminino , Humanos , Gravidez , Sensibilidade e Especificidade , Adulto Jovem
6.
Fetal Pediatr Pathol ; 40(6): 707-716, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32202960

RESUMO

Background 6-Pyruvoyl-tetrahydropterin synthase (PTS) is the key enzyme in BH4 synthesis. PTS deficiency is classified as severe type and mild type, and the prognosis and treatment differ for these types. Distinguishing between two types in the early stage is difficult. Reference to reported cases is needed for interpretation of the correlation between genotype and prognosis. Case report: We report a full-term female newborn with mild PTS deficiency. On the day 21 after birth, the phenylalanine level was 859.6 mmol/L (reference range: 30-117 mmol/L). After 1 year of observation, the patient was found to be in a healthy condition without treatment. Conclusions: Although the phenylalanine level is high in mild PTS deficiency patients after birth, some of them may have few symptoms with no treatment. We review 19 cases and find 8 mutations of PTS that may be associated with mild PTS deficiency.


Assuntos
Fenilcetonúrias , Feminino , Genótipo , Humanos , Recém-Nascido , Fósforo-Oxigênio Liases/deficiência , Fósforo-Oxigênio Liases/genética
7.
Opt Express ; 28(15): 22135-22143, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32752480

RESUMO

Two-dimensional van der Waals heterostructures (vdWHs) are drawing growing interest in the investigation of their valley polarization properties of localized excitons. However, most of the reported vdWHs were made by micro-mechanical peeling, limiting their large-scale production and practical applications. Furthermore, the circular polarization characters of localized excitons in WSe2/WS2 heterostructures remain elusive. Here, a bidirectional-flow physical vapor deposition technique was employed for the synthesis of the WSe2/WS2 type-II vertical heterostructures. The interfaces of such heterojunctions are sharp and clean, making the neutral excitons of the constituent layers quenched, which significantly highlights the luminescence of the local excitons. The circular polarization of localized excitons in this WSe2/WS2 heterostructure was demonstrated by circularly-polarized PL spectroscopy. The degree of the circular polarization of the localized excitons was determined as 7.17% for σ- detection and 4.78% for σ+ detection. Such local excitons play a critical role in a quantum emitter with enhanced spontaneous emission rate that could lead to the evolution of LEDs. Our observations provide valuable information for the exploration of intriguing excitonic physics and the applications of innovative local exciton devices.

8.
Opt Express ; 28(9): 13260-13268, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403803

RESUMO

Interlayer excitons (IX) are produced by the spatially separated electron-hole pairs due to the robust Coulomb interactions in van der Waals transition metal dichalcogenide (TMDC) heterostructures (HSS). IX is characterized by a larger binding energy, and its lifetime is orders of magnitude longer than that of the direct excitons, providing a significant platform for the manufacture of long-lived exciton devices and the exploration of exciton quantum gas. However, the studies are restricted to the single interlayer exciton, and the simultaneous capture and study of double IX remain challenging in the WSe2/WS2 HS. Here, we demonstrate the existence of double indirect IX in the WSe2/WS2 HS with the emission centers at 1.4585eV (∼25.9meV wide) and 1.4885 eV (∼14.4 meV wide) at cryogenic temperature. Interestingly, the intensities of the double IX emission peaks are almost equal, and the energy difference between them is in a good agreement with the cleavage value of the WS2 conduction band (CB). Additionally, diverse types of excitons in the individual materials were successfully observed in the PL spectra at 8 K. Such unique double IX features, in combination with excellent exciton identification, open up new opportunities for further investigations for new physical properties of TMDCs and explorations for the technological innovation of exciton devices.

9.
Cancer Imaging ; 24(1): 55, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725034

RESUMO

BACKGROUND: This study aimed to evaluate the efficacy of radiomics signatures derived from polyenergetic images (PEIs) and virtual monoenergetic images (VMIs) obtained through dual-layer spectral detector CT (DLCT). Moreover, it sought to develop a clinical-radiomics nomogram based on DLCT for predicting cancer stage (early stage: stage I-II, advanced stage: stage III-IV) in pancreatic ductal adenocarcinoma (PDAC). METHODS: A total of 173 patients histopathologically diagnosed with PDAC and who underwent contrast-enhanced DLCT were enrolled in this study. Among them, 49 were in the early stage, and 124 were in the advanced stage. Patients were randomly categorized into training (n = 122) and test (n = 51) cohorts at a 7:3 ratio. Radiomics features were extracted from PEIs and 40-keV VMIs were reconstructed at both arterial and portal venous phases. Radiomics signatures were constructed based on both PEIs and 40-keV VMIs. A radiomics nomogram was developed by integrating the 40-keV VMI-based radiomics signature with selected clinical predictors. The performance of the nomogram was assessed using receiver operating characteristic (ROC) curves, calibration curves, and decision curves analysis (DCA). RESULTS: The PEI-based radiomics signature demonstrated satisfactory diagnostic efficacy, with the areas under the ROC curves (AUCs) of 0.92 in both the training and test cohorts. The optimal radiomics signature was based on 40-keV VMIs, with AUCs of 0.96 and 0.94 in the training and test cohorts. The nomogram, which integrated a 40-keV VMI-based radiomics signature with two clinical parameters (tumour diameter and normalized iodine density at the portal venous phase), demonstrated promising calibration and discrimination in both the training and test cohorts (0.97 and 0.91, respectively). DCA indicated that the clinical-radiomics nomogram provided the most significant clinical benefit. CONCLUSIONS: The radiomics signature derived from 40-keV VMI and the clinical-radiomics nomogram based on DLCT both exhibited exceptional performance in distinguishing early from advanced stages in PDAC, aiding clinical decision-making for patients with this condition.


Assuntos
Carcinoma Ductal Pancreático , Estadiamento de Neoplasias , Nomogramas , Neoplasias Pancreáticas , Tomografia Computadorizada por Raios X , Humanos , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Idoso , Tomografia Computadorizada por Raios X/métodos , Adulto , Estudos Retrospectivos , Radiômica
10.
Adv Sci (Weinh) ; 11(22): e2400275, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38504472

RESUMO

Energy loss in perovskite grain boundaries (GBs) is a primary limitation toward high-efficiency perovskite solar cells (PSCs). Two critical strategies to address this issue are high-quality crystallization and passivation of GBs. However, the established methods are generally carried out discretely due to the complicated mechanisms of grain growth and defect formation. In this study, a combined method is proposed by introducing 3,4,5-Trifluoroaniline iodide (TFAI) into the perovskite precursor. The TFAI triggers the union of nano-sized colloids into microclusters and facilitates the complete phase transition of α-FAPbI3 at room temperature. The controlled chemical reactivity and strong steric hindrance effect enable the fixed location of TFAI and suppress defects at GBs. This combination of well-crystallized perovskite grains and effectively passivated GBs leads to an improvement in the open circuit voltage (Voc) of PSCs from 1.08 V to 1.17 V, which is one of the highest recorded Voc without interface modification. The TFAI-incorporated device achieved a champion PCE of 24.81%. The device maintained a steady power output near its maximum power output point, showing almost no decay over 280 h testing without pre-processing.

11.
ACS Appl Mater Interfaces ; 16(15): 19247-19253, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591143

RESUMO

Two-dimensional (2D) transitional metal dichalcogenides (TMDs) have garnered significant attention due to their potential for next-generation electronics, which require device scaling. However, the performance of TMD-based field-effect transistors (FETs) is greatly limited by the contact resistance. This study develops an effective strategy to optimize the contact resistance of WSe2 FETs by combining contact doping and 2D metallic electrode materials. The contact regions were doped using a laser, and the metallic TaSe2 flakes were stacked on doped WSe2 as electrodes. Doping the contact areas decreases the depletion width, while introducing the TaSe2 contact results in a lower Schottky barrier. This method significantly improves the electrical performance of the WSe2 FETs. The doped WSe2/TaSe2 contact exhibits an ultralow Schottky barrier height of 65 meV and a contact resistance of 11 kΩ·µm, which is a 50-fold reduction compared to the conventional Cr/Au contact. Our method offers a way on fabricating high-performance 2D FETs.

12.
RSC Adv ; 13(12): 7780-7788, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36909766

RESUMO

Two-dimensional InSe has been considered as a promising candidate for novel optoelectronic devices owing to large electron mobility and a near-infrared optical band gap. However, its widespread applications suffer from environmental instability. A lot of theoretical studies on the degradation mechanism of InSe have been reported whereas the experimental proofs are few. Meanwhile, the role of the extrinsic environment is still obscure during the degradation. As a common technique of studying the degradation mechanism of 2D materials, laser irradiation exhibits many unique advantages, such as being fast, convenient, and offering in situ compatibility. Here, we have developed a laser-treated method, which involves performing repeated measurements at the same point while monitoring the evolution of the resulting PL, to systematically study the photo-induced degradation process of InSe. Interestingly, we observe different evolution behavior of PL intensity under weak irradiation and strong irradiation. Our experimental results indicate the vacancy passivation and degrading effect simultaneously occurring in InSe under a weak laser irradiation, resulting in the PL increasing first and then decreasing during the measurement. Meanwhile we also notice that the passivation has a stronger effect on the PL than the degrading effect of weak oxidation. In contrast, under a strong laser irradiation, the InSe suffers serious destruction caused by excess heating and intense oxidation. This leads to a direct decrease of PL and corresponding oxidative products. Our work provides a reliable experimental supplement to the photo oxidation study of InSe and opens up a new avenue to regulate the PL of InSe.

13.
Front Oncol ; 13: 1193010, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645430

RESUMO

Objective: gastrointestinal stromal tumors (GISTs) with KIT exon 11 deletions have more malignant clinical outcomes. A radiomics model was constructed for the preoperative prediction of KIT exon 11 deletion in GISTs. Methods: Overall, 126 patients with GISTs who underwent preoperative enhanced CT were included. GISTs were manually segmented using ITK-SNAP in the arterial phase (AP) and portal venous phase (PVP) images of enhanced CT. Features were extracted using Anaconda (version 4.2.0) with PyRadiomics. Radiomics models were constructed by LASSO. The clinical-radiomics model (combined model) was constructed by combining the clinical model with the best diagnostic effective radiomics model. ROC curves were used to compare the diagnostic effectiveness of radiomics model, clinical model, and combined model. Diagnostic effectiveness among radiomics model, clinical model and combine model were analyzed in external cohort (n=57). Statistics were carried out using R 3.6.1. Results: The Radscore showed favorable diagnostic efficacy. Among all radiomics models, the AP-PVP radiomics model exhibited excellent performance in the training cohort, with an AUC of 0.787 (95% CI: 0.687-0.866), which was verified in the test cohort (AUC=0.775, 95% CI: 0.608-0.895). Clinical features were also analyzed. Among the radiomics, clinical and combined models, the combined model showed favorable diagnostic efficacy in the training (AUC=0.863) and test cohorts (AUC=0.851). The combined model yielded the largest AUC of 0.829 (95% CI, 0.621-0.950) for the external validation of the combined model. GIST patients could be divided into high or low risk subgroups of recurrence and mortality by the Radscore. Conclusion: The radiomics models based on enhanced CT for predicting KIT exon 11 deletion mutations have good diagnostic performance.

14.
Nanomaterials (Basel) ; 13(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36903711

RESUMO

Two-dimensional (2D) materials and their van der Waals stacked heterostructures (vdWH) are becoming the rising and glowing candidates in the emerging flexible nanoelectronics and optoelectronic industry. Strain engineering proves to be an efficient way to modulate the band structure of 2D materials and their vdWH, which will broaden understanding and practical applications of the material. Therefore, how to apply desired strain to 2D materials and their vdWH is of great importance to get the intrinsic understanding of 2D materials and their vdWH with strain modulation. Here, systematic and comparative studies of strain engineering on monolayer WSe2 and graphene/WSe2 heterostructure are studied by photoluminescence (PL) measurements under uniaxial tensile strain. It is found that contacts between graphene and WSe2 interface are improved, and the residual strain is relieved through the pre-strain process, which thus results in the comparable shift rate of the neutral exciton (A) and trion (AT) of monolayer WSe2 and graphene/WSe2 heterostructure under the subsequent strain release process. Furthermore, the PL quenching occurred when the strain is restored to the original position also indicates the pre-strain process to 2D materials, and their vdWH is important and necessary for improving the interface contacts and reducing the residual strain. Thus, the intrinsic response of the 2D material and their vdWH under strain can be obtained after the pre-strain treatment. These findings provide a quick, fast and efficient way to apply desired strain and also have important significance in guiding the use of 2D materials and their vdWH in the field of flexible and wearable devices.

15.
BMJ Open ; 13(10): e076219, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37879697

RESUMO

OBJECTIVES: This study aims to assess the relative of social support and psychological distress in disease activity among patients with Crohn's disease (CD) in China, and explore whether sex moderates the relationship between disease activity and social support and psychological distress in CD. DESIGN: Our study has a cross-sectional design. SETTING: This was a single-centre study, which was conducted in Wuhan, China. PARTICIPANTS: A total of 184 patients with CD at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were enrolled in this study; of these,162 patients were included in the final analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: The main study outcome was the CD patients' clinical and questionnaire data. The association of disease activity, social support and psychological distress with patients with CD was also evaluated based on the collected data. RESULTS: A total of 162 patients with CD were enrolled. Compared with patients with CD in remission (CD-R), the patients with CD in activity (CD-A) had higher C reactive protein (CRP) (p=0.001), anaemia (p<0.001) and relapse rates in the last year (p<0.001). Independent samples t-tests indicated that the CD-A group reported lower Social Support Rating Scale scores and higher Symptom Checklist-90 scores than the CD-R group. Moreover, men with CD had lower somatisation (p=0.030) and anxiety (p=0.050) scores than women. In binary logistic regression models, the subjective support (beta=0.903, p=0.013), the clinical factors of CRP (beta=1.038, p=0.001) and psychological distress factors of anxiety (beta=1.443, p=0.008) and other (beta=1.235, p=0.042) were disease activity predictors. CONCLUSION: The findings highlight the importance of the psychological distress and social support factors that may play a role in CD patients' health. Interventions to address these issues should be part of management in CD.


Assuntos
Doença de Crohn , Angústia Psicológica , Masculino , Humanos , Feminino , Doença de Crohn/complicações , Doença de Crohn/psicologia , Estudos Transversais , Estresse Psicológico/epidemiologia , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia , Proteína C-Reativa , Hospitais , Apoio Social
16.
Adv Sci (Weinh) ; 10(5): e2205879, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36494090

RESUMO

Realization of remote wearable health monitoring (RWHM) technology for the flexible photodiodes is highly desirable in remote-sensing healthcare systems used in space stations, oceans, and forecasting warning, which demands high external quantum efficiency (EQE) and detectivity in NIR region. Traditional inorganic photodetectors (PDs) are mechanically rigid and expensive while the widely reported solution-processed mixed tin-lead (MSP) perovskite photodetectors (PPDs) exhibit a trade-off between EQE and detectivity in the NIR region. Herein, a novel functional passivating antioxidant (FPA) strategy has been introduced for the first time to simultaneously improve crystallization, restrain Sn2+ oxidization, and reduce defects in MSP perovskite films by multiple interactions between thiophene-2-carbohydrazide (TAH) molecules and cations/anions in MSP perovskite. The resultant solution-processed rigid mixed Sn-Pb PPD simultaneously achieves high EQE (75.4% at 840 nm), detectivity (1.8 × 1012 Jones at 840 nm), ultrafast response time (trise /tfall = 94 ns/97 ns), and improved stability. This work also highlights the demonstration of the first flexible photodiode using MSP perovskite and FPA strategy with remarkably high EQE (75% at 840 nm), and operational stability. Most importantly, the RWHM is implemented for the first time in the PIN MSP perovskite photodiodes to remotely monitor the heart rate of humans at rest and after-run conditions.

17.
RSC Adv ; 13(26): 18099-18107, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37323440

RESUMO

Interlayer excitons (ILEs) in the van der Waals (vdW) heterostructures of type-II band alignment transition metal dichalcogenides (TMDCs) have attracted significant interest owing to their unique exciton properties and potential in quantum information applications. However, the new dimension that emerges with the stacking of structures with a twist angle leads to a more complex fine structure of ILEs, presenting both an opportunity and a challenge for the regulation of the interlayer excitons. In this study, we report the evolution of interlayer excitons with the twist angle in the WSe2/WS2 heterostructure and identify the direct (indirect) interlayer excitons by combining photoluminescence (PL) and density functional theory (DFT) calculations. Two interlayer excitons with opposite circular polarization assigned to the different transition paths of K-K and Q-K were observed. The nature of the direct (indirect) interlayer exciton was confirmed by circular polarization PL measurement, excitation power-dependent PL measurement and DFT calculations. Furthermore, by applying an external electric field to regulate the band structure of the WSe2/WS2 heterostructure and control the transition path of the interlayer excitons, we could successfully realize the regulation of interlayer exciton emission. This study provides more evidence for the twist-angle-based control of heterostructure properties.

18.
J Cancer Res Clin Oncol ; 149(12): 10453-10463, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37278828

RESUMO

OBJECTIVE: To assess the diagnostic value of spectral parameters in differentiating adrenal adenomas from metastases based on dual-layer detector spectral CT (DLSCT). MATERIALS AND METHODS: Patients with adenomas or metastases who underwent enhanced DLSCT of the adrenals were enrolled. The CT values of virtual non-contrast images (CTVNC), iodine density (ID) values, and Z-effective (Z-eff) values, the normalized iodine density (NID) values, slopes of spectral HU curves (s-SHC), and iodine-to-CTVNC ratios of the tumors were measured in each phase. Receiver operating characteristic (ROC) curves were used to compare the diagnostic values. RESULTS: Ninety-nine patients with 106 adrenal lesions (63 adenomas, 43 metastases) were included. In the venous phase, all spectral parameters were significantly different between adenomas and metastases (all p < 0.05). The combined spectral parameters showed a better diagnostic performance in the venous phase than in other phase (p < 0.05). The iodine-to-CTVNC value had a larger area under the ROC curve (AUC) than the other spectral parameters in the differential diagnosis of adenomas and metastases, with a diagnostic sensitivity and specificity of 74.4% and 91.9%, respectively. In the differential diagnosis of lipid-rich adenomas, lipid-poor adenomas and metastases, the CTVNC value and s-SHC value also had a larger AUC than the other spectral parameters, with a diagnostic sensitivity of 97.7%, 79.1% and specificity of 91.2%, 93.1%, respectively. CONCLUSION: On DLSCT, the combined spectral parameters in the venous phase could help better distinguish adrenal adenomas from metastases. The iodine-to-CTVNC, CTVNC and s-SHC values had the highest AUC values in differentiating adenomas, lipid-rich adenomas and lipid-poor adenomas from metastases, respectively.


Assuntos
Adenoma , Iodo , Humanos , Diagnóstico Diferencial , Tomografia Computadorizada por Raios X/métodos , Adenoma/diagnóstico por imagem , Adenoma/patologia , Sensibilidade e Especificidade , Lipídeos , Estudos Retrospectivos
19.
ACS Appl Mater Interfaces ; 15(30): 36447-36456, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37485977

RESUMO

Preferred crystalline orientation at the surface of quasi-2D organic-inorganic halide perovskites is crucial to promote vertical carrier transport and interface carrier extraction, which further contribute to device efficiency and stability in photovoltaic applications. However, loose unoriented and defective surfaces are inevitably formed in the crystallization process, especially with the introduction of bulky organic cations into the quasi-2D perovskites. Here, a facile and effective surface polishing method using a natural-friendly green solvent, 2,2,2-trifluoroethanol, is proposed to reconstruct the surface. After solvent polishing, the randomly oriented phases containing trap sites on the surface are successfully removed, and the compact vertical-oriented phases underneath are revealed with less defectiveness and better smoothness, which greatly facilitates carrier transport and interfacial charge extraction. Consequently, the green solvent polished devices show a boosting efficiency of 18.38% with a high open-circuit voltage of 1.21 V. The devices also show improved storage and operational stability.

20.
Adv Mater ; 35(46): e2302298, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37578639

RESUMO

Perovskite single-crystal redissolution (PSCR) strategy is highly desired for efficient formamidinium lead triiodide (FAPbI3 ) perovskite photovoltaics with enhanced phase purity, improved film quality, low trap-state density, and good stability. However, the phase transition and crystallization dynamics of FAPbI3 remain unclear in the PSCR process compared to the conventional fabrication from the mixing of precursor materials. In this work, a green-solvent-assisted (GSA) method is employed to synthesize centimeter-sized α-FAPbI3 single crystals, which serve as the high-purity precursor to fabricate perovskite films. The α-FAPbI3 PSCR strategy facilitates direct α-phase formation and inhibits the complex intermediate phases monitored by in situ grazing-incidence wide-angle X-ray scattering. Moreover, the α-phase stability is prolonged due to the relaxation of the residual lattice strain through the isotropic orientation phase growth. Consequently, the GSA-assisted PSCR strategy effectively promotes crystallization and suppresses non-radiative recombination in perovskite solar cells, which boosts the device efficiency from 22.08% to 23.92% with significantly enhanced open circuit voltage. These findings provide deeper insight into the PSCR process in terms of its efficacy in phase formation and lattice strain release. The green low-cost solvent may also offer a new and ideal solvent candidate for large-scale production of perovskite photovoltaics.

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