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1.
Front Psychiatry ; 15: 1248424, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38726382

RESUMEN

Background: Coronary heart disease has a high incidence rate, a high mortality rate, a high recurrence rate, and a high medical cost. In addition, some patients need to undergo percutaneous coronary artery stent implantation (CASI), which is a kind of traumatic treatment. Patients can easily experience negative emotions such as anxiety and depression after surgery, which seriously affects quality of life. Objectives: The aim of this study was to evaluate the effectiveness of an empowerment-based telephone follow-up intervention on resilience and quality of life in patients who underwent CASI. Design: The design of the study is a randomized controlled trial. Methods: A total of 92 patients were recruited after CASI from the Internal Medicine Cardiovascular Department of a Grade A tertiary hospital in Xi'an, China. The patients were randomly divided into a control group and an intervention group. The control group performed routine care, whereas the intervention group developed a telephone follow-up program based on empowerment theory while carrying out routine care. Patients were investigated using the coronary heart disease-related knowledge questionnaire, the Connor-Davidson Resilience Scale (CD-RISC), and the 36-Item Short-Form Health Survey (SF-36) to compare the effects of the intervention before and after 1 month of intervention. Results: After a 1-month telephone follow-up intervention based on the empowerment theory for patients after CASI, the variations in knowledge related to coronary heart disease and all of its subscale scores were greater in the intervention group than in the control group. Except for the three dimensions of risk factor, induction factor, and rehabilitation-related knowledge, the variations in knowledge related to coronary heart disease and the other subscale scores were significantly different between the two groups (p < 0.05). The variations in resilience and scores on the three subscales in the intervention group were greater than those in the control group, and the difference between the two groups was statistically significant (p < 0.05). The variations in the quality of life and overall health, emotional functions, and social functions were significantly greater in the intervention group than in the control group (p < 0.05). Conclusions: A telephone follow-up intervention based on the empowerment theory can effectively improve the resilience and quality of life of patients after CASI. This follow-up approach can provide a theoretical basis and practical reference for hospitals and communities to carry out targeted continuing nursing for patients after CASI. The long-term effects of the intervention and its underlying mechanisms require further study. Clinical trial registration: http://www.chictr.org.cn/showproj.aspx?proj=173682, identifier ChiCTR2200064950.

2.
Radiology ; 311(2): e230750, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38713024

RESUMEN

Background Multiparametric MRI (mpMRI) improves prostate cancer (PCa) detection compared with systematic biopsy, but its interpretation is prone to interreader variation, which results in performance inconsistency. Artificial intelligence (AI) models can assist in mpMRI interpretation, but large training data sets and extensive model testing are required. Purpose To evaluate a biparametric MRI AI algorithm for intraprostatic lesion detection and segmentation and to compare its performance with radiologist readings and biopsy results. Materials and Methods This secondary analysis of a prospective registry included consecutive patients with suspected or known PCa who underwent mpMRI, US-guided systematic biopsy, or combined systematic and MRI/US fusion-guided biopsy between April 2019 and September 2022. All lesions were prospectively evaluated using Prostate Imaging Reporting and Data System version 2.1. The lesion- and participant-level performance of a previously developed cascaded deep learning algorithm was compared with histopathologic outcomes and radiologist readings using sensitivity, positive predictive value (PPV), and Dice similarity coefficient (DSC). Results A total of 658 male participants (median age, 67 years [IQR, 61-71 years]) with 1029 MRI-visible lesions were included. At histopathologic analysis, 45% (294 of 658) of participants had lesions of International Society of Urological Pathology (ISUP) grade group (GG) 2 or higher. The algorithm identified 96% (282 of 294; 95% CI: 94%, 98%) of all participants with clinically significant PCa, whereas the radiologist identified 98% (287 of 294; 95% CI: 96%, 99%; P = .23). The algorithm identified 84% (103 of 122), 96% (152 of 159), 96% (47 of 49), 95% (38 of 40), and 98% (45 of 46) of participants with ISUP GG 1, 2, 3, 4, and 5 lesions, respectively. In the lesion-level analysis using radiologist ground truth, the detection sensitivity was 55% (569 of 1029; 95% CI: 52%, 58%), and the PPV was 57% (535 of 934; 95% CI: 54%, 61%). The mean number of false-positive lesions per participant was 0.61 (range, 0-3). The lesion segmentation DSC was 0.29. Conclusion The AI algorithm detected cancer-suspicious lesions on biparametric MRI scans with a performance comparable to that of an experienced radiologist. Moreover, the algorithm reliably predicted clinically significant lesions at histopathologic examination. ClinicalTrials.gov Identifier: NCT03354416 © RSNA, 2024 Supplemental material is available for this article.


Asunto(s)
Aprendizaje Profundo , Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Estudios Prospectivos , Imágenes de Resonancia Magnética Multiparamétrica/métodos , Persona de Mediana Edad , Algoritmos , Próstata/diagnóstico por imagen , Próstata/patología , Biopsia Guiada por Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos
3.
Artículo en Inglés | MEDLINE | ID: mdl-38706177

RESUMEN

Perovskite nanocrystal (PeNC) arrays are showing a promising future in the next generation of micro-light-emitting-diode (micro-LED) displays due to the narrow emission linewidth and adjustable peak wavelength. Electrohydrodynamic (EHD) inkjet printing, with merits of high resolution, uniformity, versatility, and cost-effectiveness, is among the competent candidates for constructing PeNC arrays. However, the fabrication of red light-emitting CsPbBrxI(3-x) nanocrystal arrays for micro-LED displays still faces challenges, such as low brightness and poor stability. This work proposes a design for a red PeNC colloidal ink that is specialized for the EHD inkjet printing of three-dimensional PeNC arrays with enhanced luminescence and stability as well as being adaptable to both rigid and flexible substrates. Made of a mixture of PeNCs, polymer polystyrene (PS), and a nonpolar xylene solvent, the PeNC colloidal ink enables precise control of array sizes and shapes, which facilitates on-demand micropillar construction. Additionally, the inclusion of PS significantly increases the brightness and environmental stability. By adopting this ink, the EHD printer successfully fabricated full-color 3D PeNC arrays with a spatial resolution over 2500 ppi. It shows the potential of the EHD inkjet printing strategy for high-resolution and robust PeNC color conversion layers for micro-LED displays.

4.
Vascular ; : 17085381241247613, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38631687

RESUMEN

OBJECTIVE: To review our multi-institutional experience with endovascular therapy for right subclavian artery occlusive disease and to evaluate the long-term outcomes. METHODS: We retrospectively evaluated all patients with right subclavian artery stenosis and occlusive disease who underwent endovascular therapy between March 2014 and September 2022 at two institutions. Patient baseline demographics, lesion characteristics, treatment strategies, and in-hospital and follow-up outcomes were prospectively collected and retrospectively analyzed. RESULTS: Between March 2014 and September 2022, 73 patients underwent endovascular treatment at the two institutions. The dominant cause of lesions in this cohort was atherosclerosis. Three different types of lesions were summarized, and the corresponding endovascular strategies were performed. 66 patients (90.4%) underwent successful endovascular treatment, and 62 patients (84.9%) underwent balloon-expandable stent deployment. The mean perioperative in-hospital stay was 4.0 days (range, 3-6 days). Two patients died due to myocardial infarction, and one died of cerebral hemorrhage resulting from a traffic accident within 30 days of the intervention. The median follow-up time was 31.6 months (range, 12-96 months). No complications, including death, stroke, stent fractures, or migration, were noted in any patient during the follow-up period. The overall complication rate was 7/73 (9.6%), and 5/7 (6.9%) of the complications required reintervention. CONCLUSIONS: Endovascular treatment of right subclavian artery lesions is safe, effective, and technically achievable. The reasonable use of balloon-expandable stents can achieve satisfactory outcomes with accurate orientation and promising patency.

5.
ACS Nano ; 18(15): 10454-10463, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38572806

RESUMEN

DNA isothermal amplification techniques have been applied extensively for evaluating nucleic acid inputs but cannot be implemented directly on other types of biomolecules. In this work, we designed a proximity activation mechanism that converts protein input into DNA barcodes for the DNA exponential amplification reaction, which we termed PEAR. Several design parameters were identified and experimentally verified, which included the choice of enzymes, sequences of proximity probes and template strand via the NUPACK design tool, and the implementation of a hairpin lock on the proximity probe structure. Our PEAR system was surprisingly more robust against nonspecific DNA amplification, which is a major challenge faced in existing formats of the DNA-based exponential amplification reaction. The as-designed PEAR exhibited good target responsiveness for three protein models with a dynamic range of 4-5 orders of magnitude down to femtomolar input concentration. Overall, our proposed protein-to-DNA converter module led to the development of a stable and robust configuration of the DNA exponential amplification reaction to achieve high signal gain. We foresee this enabling the use of protein inputs for more complex molecular evaluation as well as ultrasensitive protein detection.


Asunto(s)
Técnicas Biosensibles , ADN , ADN/genética , ADN/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Biosensibles/métodos
6.
Opt Express ; 32(6): 8929-8936, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571138

RESUMEN

A modified two-level model is proposed to study the spatially resolved current density distribution of GaN-based green miniaturized light-emitting diodes (mini-LEDs), combining with microscopic hyperspectral imaging. We found that the spatially resolved current density distribution reveals both the radiative and non-radiative recombination mappings, which can also be provided separately by this model. In addition, higher current density is not necessarily correlated with higher photon emission, especially for the regions around the electrode edges, where the high current density suggests current crowding and defect-related non-radiative recombination. The current density distribution of mini-LEDs is further verified by the laser-beam-induced current (LBIC) and the spatially resolved mappings of peak wavelength and FWHM. The modified two-level model also offers radiative/non-radiative mappings and is proved to be beneficial to determine the micro-zone current density distribution and to reveal the intrinsic radiative/non-radiative recombination mechanism of mini-LEDs.

7.
Environ Sci Technol ; 58(18): 8009-8019, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38557036

RESUMEN

With the increasing use of metal-organic frameworks (MOFs), they will inevitably enter the environment intentionally or unintentionally. However, the effects of MOFs on plant growth are poorly understood. Here, we investigated the effects of exposure of the rhizosphere to MOFs on plant growth. MIL-101(Cr) was selected as a research model due to its commercial availability and wide use. Soybean plants at the two-leaf stage were subjected to various durations (1-7 days) and concentrations (0-1000 mg/L) of exposure in hydroculture with a control group treated with ultrapure water. We found that MIL-101(Cr) had a positive effect on soybean growth at a lower dose (i.e., 200 mg/L); however, at higher doses (i.e., 500 and 1000 mg/L), it exhibited significant toxicity to plant growth, which is evidenced by leaf damage. To investigate the mechanism of this effect, we used Cr as an indicator to quantify, track, and image MIL-101(Cr) in the plant with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Results indicated that MIL-101(Cr) primarily accumulated in the cortex of roots (up to 40 times higher than that in stems), with limited translocation to stems and negligible presence in leaves and cotyledons. In addition, metabolomic analysis of soybeans indicated that low-dose MIL-101(Cr) could increase the sucrose content of soybean roots to promote plant growth, while a high dose could induce lipid oxidation in roots. This study provides valuable insights into the ecological toxicology of MOFs and underscores the importance of assessing their environmental impact for sustainable agricultural practices.


Asunto(s)
Glycine max , Estructuras Metalorgánicas , Glycine max/efectos de los fármacos , Glycine max/crecimiento & desarrollo , Desarrollo de la Planta/efectos de los fármacos
8.
J Org Chem ; 89(9): 6474-6488, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38607334

RESUMEN

We report a step-economic strategy for the direct synthesis of spiro polycyclic N-heterocycles and indolecarbazole-fused naphthoquinones by merging oxidative coupling and cascade palladium-catalyzed intramolecular oxidative cyclization. In the protocol, bi-indolylnaphthoquinones were first synthesized by oxidative coupling of indoles and naphthoquinones. Subsequent cascade palladium-catalyzed intramolecular oxidative cyclization of bi-indolylnaphthoquinones gave spiro polycyclic N-heterocycles and indolecarbazoles. The intramolecular oxidative cyclization approach could also be realized by the presence or absence of iron catalysts under standard conditions. This protocol is featured with moderate to excellent yields, a wide substrate scope, and divergent structures of products.

9.
Abdom Radiol (NY) ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38512516

RESUMEN

OBJECTIVE: Automated methods for prostate segmentation on MRI are typically developed under ideal scanning and anatomical conditions. This study evaluates three different prostate segmentation AI algorithms in a challenging population of patients with prior treatments, variable anatomic characteristics, complex clinical history, or atypical MRI acquisition parameters. MATERIALS AND METHODS: A single institution retrospective database was queried for the following conditions at prostate MRI: prior prostate-specific oncologic treatment, transurethral resection of the prostate (TURP), abdominal perineal resection (APR), hip prosthesis (HP), diversity of prostate volumes (large ≥ 150 cc, small ≤ 25 cc), whole gland tumor burden, magnet strength, noted poor quality, and various scanners (outside/vendors). Final inclusion criteria required availability of axial T2-weighted (T2W) sequence and corresponding prostate organ segmentation from an expert radiologist. Three previously developed algorithms were evaluated: (1) deep learning (DL)-based model, (2) commercially available shape-based model, and (3) federated DL-based model. Dice Similarity Coefficient (DSC) was calculated compared to expert. DSC by model and scan factors were evaluated with Wilcox signed-rank test and linear mixed effects (LMER) model. RESULTS: 683 scans (651 patients) met inclusion criteria (mean prostate volume 60.1 cc [9.05-329 cc]). Overall DSC scores for models 1, 2, and 3 were 0.916 (0.707-0.971), 0.873 (0-0.997), and 0.894 (0.025-0.961), respectively, with DL-based models demonstrating significantly higher performance (p < 0.01). In sub-group analysis by factors, Model 1 outperformed Model 2 (all p < 0.05) and Model 3 (all p < 0.001). Performance of all models was negatively impacted by prostate volume and poor signal quality (p < 0.01). Shape-based factors influenced DL models (p < 0.001) while signal factors influenced all (p < 0.001). CONCLUSION: Factors affecting anatomical and signal conditions of the prostate gland can adversely impact both DL and non-deep learning-based segmentation models.

10.
Spine J ; 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38499068

RESUMEN

BACKGROUND CONTEXT: Long-segment pedicle screw instrumentation is widely used to treat complex spinal disorders. Rods are routinely precontoured to maximize assistance on the correcting side of the deformity, but there often exists a residual gap discrepancy between the precontoured rods and screw tulips. No previous research has investigated the diminished pullout strength of the most proximal or distal pedicle screw resulting from a mismatched rod in long-segment pedicle screw instrumentation. PURPOSE: The present study aimed to investigate the decreased pullout force of pedicle screws affected by the gap discrepancy when forcefully engaging a mismatched rod into a tulip in a normal-density porcine spine. STUDY DESIGN: The pedicle screw fixation strength under axial pullout force was compared among three different gap discrepancies between rods and tulips using long porcine spine segments. METHODS: Twelve porcine lumbar vertebrae (L3-L6) were implanted with pedicle screws and rods. Screws on one side had no gap between the tulip and rod (0-mm group), while the most proximal screw on the other side had an intentional gap of 3 mm (3-mm group) or 6 mm (6-mm group). Three hours after forcefully engaging the rod into the tulips at room temperature, the set screws in all specimens were loosened, and each specimen was dissected into individual vertebrae for subsequent pullout testing. RESULTS: The control group exhibited significantly greater pullout strength (1987.68 ± 126.80 N) than the groups from different rod-tulip configurations (p<.05), with significantly greater strength in the 3-mm group (945.62 ± 97.43 N) than the 6-mm group (655.30 ± 194.49 N) (p<.05). Only 47.6% and 33.0% of the pullout strength was retained in the 3-mm and 6-mm groups, respectively, compared to the control group. CONCLUSIONS: Gap discrepancies between rods and tulips can significantly reduce pedicle screw pullout strength, with a correlation between decreased strength and increased gaps. Surgeons should avoid forcefully engaging mismatched rods and consider well-fitted contoured rods in spinal surgery to minimize the risk of screw loosening. CLINICAL SIGNIFICANCE: The gap discrepancy between rod and tulip significantly affected pullout strength, with greater gaps leading to reduced strength. Forcefully engaging mismatched rods into tulips in degenerative spinal surgery should be avoided to minimize the risk of early screw pullout.

11.
Clin Breast Cancer ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38494415

RESUMEN

OBJECTIVES: To develop predictive nomograms based on clinical and ultrasound features and to improve the clinical strategy for US BI-RADS 4A lesions. METHODS: Patients with US BI-RADS 4A lesions from 3 hospitals between January 2016 and June 2020 were retrospectively included. Clinical and ultrasound features were extracted to establish nomograms CE (based on clinical experience) and DL (based on deep-learning algorithm). The performances of nomograms were evaluated by receiver operator characteristic curves, calibration curves and decision curves. Diagnostic performances with DL of radiologists were analyzed. RESULTS: 1616 patients from 2 hospitals were randomly divided into training and internal validation cohorts at a ratio of 7:3. Hundred patients from another hospital made up external validation cohort. DL achieved more optimized AUCs than CE (internal validation: 0.916 vs. 0.863, P < .01; external validation: 0.884 vs. 0.776, P = .05). The sensitivities of DL were higher than CE (internal validation: 81.03% vs. 72.41%, P = .044; external validation: 93.75% vs. 81.25%, P = .4795) without losing specificity (internal validation: 84.91% vs. 86.47%, P = .353; external validation: 69.14% vs. 71.60%, P = .789). Decision curves indicated DL adds more clinical net benefit. With DL's assistance, both radiologists achieved higher AUCs (0.712 vs. 0.801; 0.547 vs. 0.800), improved specificities (70.93% vs. 74.42%, P < .001; 59.3% vs. 81.4%, P = .004), and decreased unnecessary biopsy rates by 6.7% and 24%. CONCLUSION: DL was developed to discriminate US BI-RADS 4A lesions with a higher diagnostic power and more clinical net benefit than CE. Using DL may guide clinicians to make precise clinical decisions and avoid overtreatment of benign lesions.

12.
J Am Chem Soc ; 146(11): 7858-7867, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38457662

RESUMEN

Developing efficient bifunctional materials is highly desirable for overall proton membrane water splitting. However, the design of iridium materials with high overall acidic water splitting activity and durability, as well as an in-depth understanding of the catalytic mechanism, is challenging. Herein, we successfully developed subnanoporous Ir3Ni ultrathin nanocages with high crystallinity as bifunctional materials for acidic water splitting. The subnanoporous shell enables Ir3Ni NCs optimized exposure of active sites. Importantly, the nickel incorporation contributes to the favorable thermodynamics of the electrocatalysis of the OER after surface reconstruction and optimized hydrogen adsorption free energy in HER electrocatalysis, which induce enhanced intrinsic activity of the acidic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Together, the Ir3Ni nanocages achieve 3.72 A/mgIr(η=350 mV) and 4.47 A/mgIr(η=40 mV) OER and HER mass activity, which are 18.8 times and 3.3 times higher than that of commercial IrO2 and Pt, respectively. In addition, their highly crystalline identity ensures a robust nanostructure, enabling good catalytic durability during the oxygen evolution reaction after surface oxidation. This work provides a new revenue toward the structural design and insightful understanding of metal alloy catalytic mechanisms for the bifunctional acidic water splitting electrocatalysis.

13.
Front Immunol ; 15: 1358719, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38533497

RESUMEN

Neuroinflammation is a common pathological process in various neurological disorders, including stroke, Alzheimer's disease, Parkinson's disease, and others. It involves the activation of glial cells, particularly astrocytes, and the release of inflammatory mediators. Lipocalin-2 (Lcn-2) is a secretory protein mainly secreted by activated astrocytes, which can affect neuroinflammation through various pathways. It can also act as a pro-inflammatory factor by modulating astrocyte activation and polarization through different signaling pathways, such as NF-κB, and JAK-STAT, amplifying the inflammatory response and aggravating neural injury. Consequently, Lcn-2 and astrocytes may be potential therapeutic targets for neuroinflammation and related diseases. This review summarizes the current knowledge on the role mechanisms, interactions, and therapeutic implications of Lcn-2 and astrocytes in neuroinflammation.


Asunto(s)
Astrocitos , Enfermedades Neuroinflamatorias , Humanos , Astrocitos/metabolismo , Lipocalina 2/metabolismo , Inflamación/metabolismo , Neuroglía/metabolismo
14.
Comput Biol Med ; 173: 108292, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38513387

RESUMEN

Lung cancer is one of the most common malignant tumors around the world, which has the highest mortality rate among all cancers. Traditional Chinese medicine (TCM) has attracted increased attention in the field of lung cancer treatment. However, the abundance of ingredients in Chinese medicines presents a challenge in identifying promising ingredient candidates and exploring their mechanisms for lung cancer treatment. In this work, two network-based algorithms were combined to calculate the network relationships between ingredient targets and lung cancer targets in the human interactome. Based on the enrichment analysis of the constructed disease module, key targets of lung cancer were identified. In addition, molecular docking and enrichment analysis of the overlapping targets between lung cancer and ingredients were performed to investigate the potential mechanisms of ingredient candidates against lung cancer. Ten potential ingredients against lung cancer were identified and they may have similar effect on the development of lung cancer. The results obtained from this study offered valuable insights and provided potential avenues for the development of novel drugs aimed at treating lung cancer.


Asunto(s)
Medicamentos Herbarios Chinos , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Algoritmos , Tórax , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China
15.
Anal Chem ; 96(13): 5251-5257, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38512289

RESUMEN

The electrochemiluminescence (ECL) intensity can be regulated by ionic current passing through the microchannel, which broadened the regulation of the ECL sensors. But in the early reported sensors, the electrostatic repulsion and steric hindrance caused few targets to approach the interface of the microchannel driven by concentration difference, which reduced the detection efficiency and prolonged the detection period. In this study, different accumulation strategies, such as a positive electric field and different polarity electric fields, were designed to accumulate targets in the microchannel. The interaction of azide groups and hydrogen sulfide served as a research model. Hydrogen sulfide can react with the negatively charged azide groups in the microchannel surface to produce positively charged amino groups, decreasing the negative charge density of the microchannel and thus altering the ionic current and ECL intensity. The accumulation of hydrogen sulfide at the microchannel tip can increase the collision probability with azide groups to improve the detection efficiency, and the integration of accumulation and reaction can shorten the detection period to 28 min. The hydrogen sulfide concentration on the microchannel tip accumulated by applying different polarity electric fields was 22.3-fold higher than that accumulated by applying a positive electric field. The selected research model broadened the application range of a microchannel-based ECL sensor and confirmed the universality of the microchannel-based ECL sensor.

16.
Sci Total Environ ; 926: 171820, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38513857

RESUMEN

Atmospheric brown carbon (BrC) aerosols were investigated at two urban sites in southern (Hefei) and northern (Shijiazhuang) China during summer and winter of 2019-2020 to explore regional variability in their compositional and optical properties. Organic matter in ambient PM2.5 samples were characterized at molecular level using ultrahigh performance liquid chromatography coupled with a diode array detector and an Orbitrap mass spectrometer. Although the molecular composition of organic aerosols varied substantially over different ambient environments, they were mainly composed by CHO and CHON species in positive ionization mode while CHO and CHOS species in negative mode. The mass absorption coefficients of BrC aerosols at wavelength range 250-450 nm were relatively higher for winter samples in both cities and for Shijiazhuang samples in both seasons, partly attributed to the higher concentration levels of anthropogenic air pollutants in these environments. The absorption Ångström exponents further revealed that BrC aerosols in winter seasons and in Shijiazhuang had a greater capacity of absorption at shorter wavelengths. A total of 26 BrC species with strong absorption were unambiguously identified from different environments, which mainly consisted of CHO, CHON, and CHN species and had higher degrees of unsaturation and lower degrees of oxidation. The presence and abundance of these BrC species varied dynamically across the seasons and cities, with a greater number of species presented in the winter of Shijiazhuang. The BrC species together contributed 12-26 % in the total absorbance of light-absorbing organic components at 250-450 nm. This study highlights the regional differences in BrC properties influenced by the sources and atmospheric processes, which should be taken into account to assess their climate impacts.

17.
Anal Chem ; 96(10): 4290-4298, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38427621

RESUMEN

Halide perovskites have emerged as a highly promising class of photoelectric materials. However, the application of lead-based perovskites has been hindered by their toxicity and relatively weak stability. In this work, a composite material comprising a lead-free perovskite cesium copper iodide (CsCu2I3) nanocrystal and a metal-organic framework (MOF-801) has been synthesized through an in situ growth approach. The resulting composite material, denoted as CsCu2I3/MOF-801, demonstrates outstanding stability and exceptional optoelectronic characteristics. MOF-801 may serve a dual role by acting as a protective barrier between CsCu2I3 nanocrystals and the external environment, as well as promoting the efficient transfer of photogenerated charge carriers, thereby mitigating their recombination. Consequently, CsCu2I3/MOF-801 demonstrates its utility by providing both stability and a notably high initial photocurrent. Leveraging the inherent reactivity between H2S and the composite material, which results in the formation of Cu2S and structural alteration, an exceptionally sensitive photoelectrochemical sensor for H2S detection has been designed. This sensor exhibits a linear detection range spanning from 0.005 to 100 µM with a remarkable detection limit of 1.67 nM, rendering it highly suitable for precise quantification of H2S in rat brains. This eco-friendly sensor significantly broadens the application horizon of perovskite materials and lays a robust foundation for their future commercialization.

18.
Chem Sci ; 15(10): 3698-3706, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38455012

RESUMEN

The widespread application of metal-organic frameworks (MOFs) is seriously hindered by their structural instability and it is still very challenging to probe the stability of MOFs during application by current techniques. Here, we report a novel structure-responsive mass spectrometry (SRMS) imaging technique to probe the stability of MOFs. We discovered that intact CuBTC (as a model of MOFs) could generate the characteristic peaks of organic ligands and carbon cluster anions in laser desorption/ionization mass spectrometry, but these peaks were significantly changed when the structure of CuBTC was dissociated, thus enabling a label-free probing of the stability. Furthermore, SRMS can be performed in imaging mode to visualize the degradation kinetics and reveal the spatial heterogeneity of the stability of CuBTC. This technique was successfully applied in different application scenarios (in water, moist air, and CO2) and also validated with different MOFs. It thus provides a versatile new tool for better design and application of environment-sensitive materials.

19.
Nano Lett ; 24(12): 3661-3669, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38408021

RESUMEN

The lack of stability of red perovskite nanocrystals (PeNCs) remains the main problem that restricts their patterning application. In this work, the dual-ligand passivation strategy was introduced to stabilize PeNCs and inhibit their halogen ion migration during high-voltage electrohydrodynamic (EHD) inkjet printing. The as-printed red arrays exhibit the highest emisson intensity and least blue shift compared with samples with other passivation strategies under a high electric field during EHD inkjet printing. Combining with blue and green PeNC inks, single-color and tricolor color conversion layer arrays were successfully printed, with minimum pixel size of 5 µm and the highest spatial resolution of 2540 dpi. The color coordinate of CsPbBrI2 NCs arrays are located close to the red point, with a color gumat of 97.28% of Rec. 2020 standard. All of these show great potential in the application of color conversion layers in a near-eye micro-LED display.

20.
Indian J Ophthalmol ; 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317325

RESUMEN

PURPOSE: To evaluate regional changes in the posterior corneal elevation after three laser refractive surgeries for correction of myopia of different degrees. SETTINGS AND DESIGN: Retrospective, comparative, and non-randomized study. METHODS: Two hundred patients (200 eyes) who underwent laser epithelial keratoplasty (LASEK), femtosecond-assisted laser in-situ keratomileusis (FS-LASIK), and small-incision lenticule extraction (SMILE) were included in this study. According to preoperative spherical equivalent (SE), each surgical group was divided into two refractive subgroups: low-to-moderate myopia (LM group) and high myopia (H group). The posterior corneal elevation from Pentacam Scheimpflug tomography was analyzed preoperatively and at 1 month, 3 months, 6 months, and 12 months postoperatively. Three subregions of the posterior cornea were divided in this study as the central, paracentral, and peripheral regions. STATISTICAL ANALYSIS USED: Generalized Estimating Equations (GEE). RESULTS: For all three surgical groups, similar changing trends were seen in the two refractive subgroups. H group presented a larger changing magnitude than the LM group in FS-LASIK over time (P < 0.05), whereas no significant difference was noted in the two refractive subgroups of LASEK or SMILE (P > 0.05). At 12 months postoperatively, the central posterior corneal elevation returned to the preoperative level in LASEK (P > 0.05) but shifted forward significantly in FS-LASIK and SMILE (P < 0.05). CONCLUSION: Different posterior corneal regions respond differently to corneal refractive surgeries. LASEK, FS-LASIK, and SMILE demonstrate different trends in the regional changes in posterior corneal elevation. The corneal shape seems more stable in LASEK than in FS-LASIK and SMILE.

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