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1.
Proc Natl Acad Sci U S A ; 121(4): e2309102121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38232287

RESUMO

Nonradicals are effective in selectively degrading electron-rich organic contaminants, which unfortunately suffer from unsatisfactory yield and uncontrollable composition due to the competitive generation of radicals. Herein, we precisely construct a local microenvironment of the carbon nitride-supported high-loading (~9 wt.%) Fe single-atom catalyst (Fe SAC) with sulfur via a facile supermolecular self-assembly strategy. Short-distance S coordination boosts the peroxymonosulfate (PMS) activation and selectively generates high-valent iron-oxo species (FeIV=O) along with singlet oxygen (1O2), significantly increasing the 1O2 yield, PMS utilization, and p-chlorophenol reactivity by 6.0, 3.0, and 8.4 times, respectively. The composition of nonradicals is controllable by simply changing the S content. In contrast, long-distance S coordination generates both radicals and nonradicals, and could not promote reactivity. Experimental and theoretical analyses suggest that the short-distance S upshifts the d-band center of the Fe atom, i.e., being close to the Fermi level, which changes the binding mode between the Fe atom and O site of PMS to selectively generate 1O2 and FeIV=O with a high yield. The short-distance S-coordinated Fe SAC exhibits excellent application potential in various water matrices. These findings can guide the rational design of robust SACs toward a selective and controllable generation of nonradicals with high yield and PMS utilization.

2.
Small ; : e2401658, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693074

RESUMO

The formation process of biofouling is actually a 4D process with both spatial and temporal dimensions. However, most traditional antifouling coatings, including slippery liquid-infused porous surface (SLIPS), are limited to performing antifouling process in the 2D coating plane. Herein, inspired by the defensive behavior of sea anemones' wielding toxic tentacles, a "4D SLIPS" (FSLIPS) is constructed with biomimetic cilia via a magnetic field self-assembly method for antifouling. The bionic cilia move in 3D space driven by an external magnetic field, thereby preventing the attachment of microorganisms. The FSLIPS releases the gaseous antifoulant (nitric oxide) at 1D time in response to light, thereby achieving a controllable biocide effect on microorganisms. The FSLIPS regulates the movement of cilia via the external magnetic field, and controls the release of NO overtime via the light response, so as to adjust the antifouling modes on demand during the day or night. The light/magnetic response mechanism endow the FSLIPS with the ability to adjust the antifouling effect in the 4D dimension of 1D time and 3D space, effectively realizing the intelligence, multi-dimensionality and precision of the antifouling process.

3.
Small ; 20(33): e2311477, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38554022

RESUMO

Seawater electrolysis is a promising but challenging strategy to generate carbon-neutral hydrogen. A grand challenge for hydrogen evolution reaction (HER) from alkaline seawater electrolysis is the development of efficient and stable electrocatalysts to overcome the limitation of sluggish kinetics. Here, a 3D nanorod hybrid catalyst is reported, which comprises heterostructure MoO2@NiMoO4 supported Ru nanoparticles (Ru/ MoO2@NiMoO4) with a size of ≈5 nm. Benefitting from the effect of strongly coupled interaction, Ru/MoO2@NiMoO4 catalyst exhibits a remarkable alkaline seawater hydrogen evolution performance, featured by a low overpotential of 184 mV at a current density of 1.0 A cm-2, superior to commercial Pt/C (338 mV). Experimental observations demonstrate that the heterostructure MoO2@NiMoO4 as an electron-accepting support makes the electron transfer from the Ru nanoparticles to MoO2, and thereby implements the electron redistribution of Ru site. Mechanistic analysis elucidates that the electron redistribution of active Ru site enhances the ability of hydrogen desorption, thereby promoting alkaline seawater HER kinetics and finally leading to a satisfactory catalysis performance at ampere-level current density of alkaline seawater electrolysis.

4.
Cardiovasc Diabetol ; 23(1): 191, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38835028

RESUMO

BACKGROUND: The purpose of this study was to explore the prognostic significance of the lesion-specific pericoronary fat attenuation index (FAI) in forecasting major adverse cardiovascular events (MACE) among patients with type 2 diabetes mellitus (T2DM). METHODS: This study conducted a retrospective analysis of 304 patients diagnosed with T2DM who underwent coronary computed tomography angiography (CCTA) in our hospital from December 2011 to October 2021. All participants were followed for a period exceeding three years. Detailed clinical data and CCTA imaging features were carefully recorded, encompassing lesion-specific pericoronary FAI, FAI of the three prime coronary arteries, features of high-risk plaques, and the coronary artery calcium score (CACS). The MACE included in the study comprised cardiac death, acute coronary syndrome (which encompasses unstable angina pectoris and myocardial infarction), late-phase coronary revascularization procedures, and hospital admissions prompted by heart failure. RESULTS: Within the three-year follow-up, 76 patients with T2DM suffered from MACE. The lesion-specific pericoronary FAI in patients who experienced MACE was notably higher compared to those without MACE (-84.87 ± 11.36 Hounsfield Units (HU) vs. -88.65 ± 11.89 HU, p = 0.016). Multivariate Cox regression analysis revealed that CACS ≥ 100 (hazard ratio [HR] = 4.071, 95% confidence interval [CI] 2.157-7.683, p < 0.001) and lesion-specific pericoronary FAI higher than - 83.5 HU (HR = 2.400, 95% CI 1.399-4.120, p = 0.001) were independently associated with heightened risk of MACE in patients with T2DM over a three-year period. Kaplan-Meier analysis showed that patients with higher lesion-specific pericoronary FAI were more likely to develop MACE (p = 0.0023). Additionally, lesions characterized by higher lesion-specific pericoronary FAI values were found to have a greater proportion of high-risk plaques (p = 0.015). Subgroup analysis indicated that lesion-specific pericoronary FAI higher than - 83.5 HU (HR = 2.017, 95% CI 1.143-3.559, p = 0.015) was independently correlated with MACE in patients with T2DM who have moderate to severe coronary calcification. Moreover, the combination of CACS ≥ 100 and lesion-specific pericoronary FAI>-83.5 HU significantly enhanced the predictive value of MACE in patients with T2DM within 3 years. CONCLUSIONS: The elevated lesion-specific pericoronary FAI emerged as an independent prognostic factor for MACE in patients with T2DM, inclusive of those with moderate to severe coronary artery calcification. Incorporating lesion-specific pericoronary FAI with the CACS provided incremental predictive power for MACE in patients with T2DM.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Valor Preditivo dos Testes , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/mortalidade , Diabetes Mellitus Tipo 2/diagnóstico , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Medição de Risco , Prognóstico , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/terapia , Fatores de Risco , Fatores de Tempo , Placa Aterosclerótica , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/mortalidade , Calcificação Vascular/epidemiologia , Adiposidade , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo Epicárdico
5.
J Magn Reson Imaging ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980200

RESUMO

BACKGROUND: Despite the advent of combination antiretroviral therapy, people living with human immunodeficiency virus (PLWH) are at an increased risk for cardiac disease. PURPOSE: To explore the presence and extent of diastolic atrial and left ventricular dysfunction in PLWH using cardiac MRI in correlation with clinical markers of disease activity. STUDY TYPE: Prospective. POPULATION: A total of 163 participants comprising 101 HIV-infected individuals (age: 52 years [42-62 years]; 92% male) and 62 age- and sex-matched healthy volunteers (age: 51 years [30-72 years]; 85% male). FIELD STRENGTH/SEQUENCE: 3.0 T, cardiac MRI including balanced steady-state free precession (SSFP) for the short-axis, two-, three-, and four-chamber views were performed. ASSESSMENT: Assessment of cardiac function and strain analysis were accomplished by CVI42 software. Blood samples for CD4+ T cells and cardiac risk factors were also collected before MRI. STATISTICAL TESTS: Independent t tests, Mann-Whitney U test, Pearson's correlation analysis, and multivariate linear analyses (significance level: P < 0.05). RESULTS: PLWH had a significantly larger left atrial volume maximum index (LAVImax: 32.6 ± 8.7 vs. 28.7 ± 8.1 mL/m2), minimum (LAVImin: 14.8 ± 5.5 vs. 11.5 ± 5.4 mL/m2,), and prior to atrial contraction (LAVIpre-a: 23.4 ± 6.7 vs. 19.7 ± 7.2 mL/m2) as compared to healthy volunteers. The LA reservoir (LAtEF: 55.0 ± 10.2 vs. 61.4 ± 10.4; Sls: 29.0 ± 8.1 vs. 33.8 ± 11.8), conduit (LApEF: 28.4 ± 8.2 vs. 32.3 ± 11.3, P = 0.01; Sle: 16.3 ± 6.5 vs. 18.9 ± 8.2), and booster pump function (LAaEF: 37.4 ± 12.4 vs. 42.7 ± 13.1, P = 0.01, Sla: 12.7 ± 5.1 vs. 14.9 ± 5.7) were all significant impaired in PLWH. Global circumferential left ventricular diastolic strain rate (LVGCS-d) was significantly lower in the HIV patients. Multivariate analysis results showed that Nadir CD4+ T cells had a significant adverse association with LVGCS-d (ß = 0.51). CONCLUSION: LA structure abnormalities and LV diastolic dysfunction were manifested in PLWH, with Nadir CD4+ T cell counts potentially serving as a risk factor for early cardiac diastolic dysfunction. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.

6.
Phys Chem Chem Phys ; 26(30): 20399-20408, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39016092

RESUMO

In carbon dioxide electrochemical reduction (CO2ER), since isolated catalysts encounter challenges in meeting the demands of intricate processes for producing multi-carbon (C2+) products, tandem catalysis is emerging as a promising approach. Nevertheless, there remains an insufficient theoretical understanding of designing tandem catalysts. Herein, we utilized density functional theory (DFT) to screen 80 tandem catalysts for efficient CO2ER to C2 products systematically, which combines the advantages of nitrogen-doped carbon-supported transition metal single-atom catalysts (M-N-C) and copper clusters. Three crucial criteria were designed to select structures for generation and transfer of *CO and facilitate C-C coupling. The optimal Cu/RuN4-pl catalyst exhibited an excellent ethanol production capacity. Additionally, the relationship between CO adsorption strength and transfer energy barrier was established, and the influence of the electronic structure on its adsorption strength was studied. This provided a novel and well-considered solution and theoretical guidance for the design of rational composition and structurally superior tandem catalysts.

7.
Neuroradiology ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39014270

RESUMO

PURPOSE: To evaluate nnU-net's performance in automatically segmenting and volumetrically measuring ocular adnexal lymphoma (OAL) on multi-sequence MRI. METHODS: We collected T1-weighted (T1), T2-weighted and T1-weighted contrast-enhanced images with/without fat saturation (T2_FS/T2_nFS, T1c_FS/T1c_nFS) of OAL from four institutions. Two radiologists manually annotated lesions as the ground truth using ITK-SNAP. A deep learning framework, nnU-net, was developed and trained using two models. Model 1 was trained on T1, T2, and T1c, while Model 2 was trained exclusively on T1 and T2. A 5-fold cross-validation was utilized in the training process. Segmentation performance was evaluated using the Dice similarity coefficient (DSC), sensitivity, and positive prediction value (PPV). Volumetric assessment was performed using Bland-Altman plots and Lin's concordance correlation coefficient (CCC). RESULTS: A total of 147 patients from one center were selected as training set and 33 patients from three centers were regarded as test set. For both Model 1 and 2, nnU-net demonstrated outstanding segmentation performance on T2_FS with DSC of 0.80-0.82, PPV of 84.5-86.1%, and sensitivity of 77.6-81.2%, respectively. Model 2 failed to detect 19 cases of T1c, whereas the DSC, PPV, and sensitivity for T1_nFS were 0.59, 91.2%, and 51.4%, respectively. Bland-Altman plots revealed minor tumor volume differences with 0.22-1.24 cm3 between nnU-net prediction and ground truth on T2_FS. The CCC were 0.96 and 0.93 in Model 1 and 2 for T2_FS images, respectively. CONCLUSION: The nnU-net offered excellent performance in automated segmentation and volumetric assessment in MRI of OAL, particularly on T2_FS images.

8.
Child Dev ; 95(4): 1237-1253, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38303138

RESUMO

This study examines social-cultural contributors and developmental outcomes of language brokers. From 2012 to 2020, three waves of data were collected from 604 Mexican-origin adolescent language brokers (Mage = 12.92, SD = 0.92, 54% girls). The study (1) identified four distinct subgroups of language brokers (efficacious, conservative, nonchalant, and burdened) who translated for mothers and fathers, after incorporating objective bilingual proficiency along with multiple dimensions of language brokering; (2) showed that early adolescents' Mexican, rather than U.S., cultural values and orientation were related to later language brokering profiles; and (3) showed that the efficacious group was the most resilient while burdened was the most vulnerable to developmental problems. Preservation of Mexican culture may facilitate language brokering experiences related to more positive developmental outcomes.


Assuntos
Emigrantes e Imigrantes , Americanos Mexicanos , Humanos , Adolescente , Feminino , Masculino , Criança , Multilinguismo , Desenvolvimento do Adolescente/fisiologia
9.
Med Teach ; : 1-13, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38796737

RESUMO

PURPOSE: Radiology instruction focuses on cultivating medical students' diagnostic thinking skills and practical competence, and lecture-based learning (LBL) is the most commonly used teaching approach. While fact-based, this type of traditional instruction is often non-engaging, leading to a shift toward student-centered models, one of which is the flipped classroom (FC). However, studies involving a comprehensive evaluation of students' experiences using the FC approach and its effects on their learning are lacking. Therefore, this study analyzed the teaching efficacy of the FC approach based on data of large groups of radiology students, accumulated over time. METHODS: Data from 636 medical radiology students taught using the FC and LBL models from 2012 to 2021 were retrospectively collected and analyzed. RESULTS: The test scores of the FC group were significantly higher than those of the LBL group, and improvements in learning initiative and learning ability were notably higher in the FC than in the LBL group. The two groups showed no significant difference in the critical thinking disposition indicator, and the proportion of students with positive critical thinking tendencies was higher in the FC than in the LBL group. The academic and social self-perception scores of the FC group were significantly higher than those of the LBL group, and there was a significant difference in Kolb's learning style. CONCLUSIONS: Based on evidence of completing pre-, in-, and after-class work, the FC approach improved students' academic performance, learning initiative, diagnostic ability, and satisfaction with learning and the teaching institution. Our findings suggest that FC instruction promotes students' assimilation and convergence of learning styles, and cultivates positive critical thinking.

10.
Mikrochim Acta ; 191(6): 362, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822867

RESUMO

Rapid and accurate in situ determination of dopamine is of great significance in the study of neurological diseases. In this work, poly (3,4-ethylenedioxythiophene): poly (styrenesulfonic acid) (PEDOT: PSS)/graphene oxide (GO) fibers were fabricated by an effective method based on microfluidic wet spinning technology. The composite microfibers with stratified and dense arrangement were continuously prepared by injecting PEDOT: PSS and GO dispersion solutions into a microfluidic chip. PEDOT: PSS/GO fiber microelectrodes with high electrochemical activity and enhanced electrochemical oxidation activity of dopamine were constructed by controlling the structure composition of the microfibers with varying flow rate. The fabricated fiber microelectrode had a low detection limit (4.56 nM) and wide detection range (0.01-8.0 µM) for dopamine detection with excellent stability, repeatability, and reproducibility. In addition, the PEDOT: PSS/GO fiber microelectrode prepared was successfully used for the detection of dopamine in human serum and PC12 cells. The strategy for the fabrication of multi-component fiber microelectrodes is a new and effective approach for monitoring the intercellular neurotransmitter dopamine and has high potential as an implantable neural microelectrode.


Assuntos
Dopamina , Grafite , Microeletrodos , Poliestirenos , Células PC12 , Dopamina/sangue , Humanos , Ratos , Animais , Poliestirenos/química , Grafite/química , Limite de Detecção , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Tiofenos/química , Dispositivos Lab-On-A-Chip , Polímeros
11.
Behav Med ; : 1-12, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874131

RESUMO

Mexican-origin youth, as a large and growing population among U.S. youth, have been disproportionately affected by COVID-19. Understanding what, when, and how sociocultural factors may influence their COVID-19 vaccine uptake could inform current and future pandemic-response interventions promoting vaccination behaviors among Mexican-origin youth. The current study takes a developmental approach to reveal the long-term and short-term sociocultural antecedents of 198 Mexican-origin adolescents' COVID-19 vaccination uptake behaviors and explores the underlying mechanism of these associations based on the Knowledge-Attitude-Behavior model. The current study adopted Wave 1 (2012-2015) and Wave 4 (2021-2022) self-reported data from a larger study. Analyses were conducted to examine four mediation models for four sociocultural antecedents-daily discrimination, ethnic discrimination, foreigner stress, and family economic stress-separately. Consistent indirect effects of higher levels of concurrent sociocultural risk factors on a lower probability of COVID-19 vaccine uptake were observed to occur through less knowledge about the COVID-19 vaccines and less positive attitudes toward the COVID-19 vaccines at Wave 4. Significant direct effects, but in opposite directions, were found for the associations between Wave 1 ethnic discrimination/Wave 4 daily discrimination and the probability of COVID-19 vaccine uptake. The findings highlight the importance of considering prior and concurrent sociocultural antecedents and the Knowledge-Attitude-Behavior pathway leading to COVID-19 vaccination uptake among Mexican-origin youth and suggest that the impact of discrimination on COVID-19 vaccination uptake may depend on the type (e.g., daily or ethnic) and the context (e.g., during the COVID-19 pandemic or not) of discrimination experienced.

12.
Angew Chem Int Ed Engl ; : e202406030, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020457

RESUMO

Single Fe sites have been explored as promising catalysts for the CO2 reduction reaction to value-added CO. Herein, we introduce a novel molten salt synthesis strategy for developing axial nitrogen-coordinated Fe-N5 sites on ultrathin defect-rich carbon nanosheets, aiming to modulate the reaction pathway precisely. This distinctive architecture weakens the spin polarization at the Fe sites, promoting a dynamic equilibrium of activated intermediates and facilitating the balance between *COOH formation and *CO desorption at the active Fe site. Notably, the synthesized FeN5, supported on defect-rich in nitrogen-doped carbon (FeN5@DNC), exhibits superior performance in CO2RR, achieving a Faraday efficiency of 99% for CO production (-0.4 V vs. RHE) in an H-cell, and maintaining a Faraday efficiency of 98% at a current density of 270 mA cm-2 (-1.0 V vs. RHE) in the flow cell. Furthermore, the FeN5@DNC catalyst is assembled as a reversible Zn-CO2 battery with a cycle durability of 24 hours. In-situ IR spectroscopy and density functional theory (DFT) calculations reveal that the axial N coordination traction induces a transformation in the crystal field and local symmetry, therefore weakening the spin polarization of the central Fe atom and lowering the energy barrier for *CO desorption.

13.
J Early Adolesc ; 42(1): 58-88, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38343898

RESUMO

The current study investigates how and under what conditions family obligation benefits Mexican American adolescents' adjustment. The study used two waves of data from 604 Mexican American adolescents (54.3% female, Mage.wave1 = 12.41 years, SD = 0.97) and their parents. Structural equation modeling revealed that both adolescents' and parents' sense of family obligation related to more supportive parenting (i.e., parental monitoring, warmth, and inductive reasoning), which linked to better adolescent adjustment (i.e., sense of life meaning, resilience, and grades). There were parent gender differences: Adolescents' family obligation was more strongly related to their reports of maternal (vs. paternal) parenting. The links also varied across informants for parenting: (a) individuals' sense of family obligation related only to their own perceptions of parenting and (b) there were more evident associations between adolescent-reported (vs. parent-reported) parenting and adolescent outcomes.

14.
J Early Adolesc ; 40(2): 249-272, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38343652

RESUMO

The current study investigated early adolescents' experiences of friend-related stress across middle school and its developmental consequences following the transition to high school. Using a sample of approximately 1,000 middle school students, four unique friend-related stress trajectories were observed across middle school: consistently low friend-related stress (57% of the sample), consistently high friend-related stress (7%), moderate and increasing friend-related stress (22%), and moderate but decreasing friend-related stress (14%). Groups characterized by higher levels of friend-related stress across middle school were linked to subsequent poorer socioemotional well-being, lower academic engagement, and greater involvement in and expectancies around risky behaviors following the transition to high school. Increased friend-related stress across the high school transition was also linked to poorer outcomes, even after taking into account earlier stress trajectories. Gender differences highlighted the particular struggles girls experience both in friend stress and in the links between friend stress and subsequent well-being.

16.
Front Pharmacol ; 15: 1181183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464717

RESUMO

Traditional Chinese medicine (TCM) is the practical experience and summary of the Chinese nation for thousands of years. It shows great potential in treating various chronic diseases, complex diseases and major infectious diseases, and has gradually attracted the attention of people all over the world. However, due to the complexity of prescription and action mechanism of TCM, the development of TCM industry is still in a relatively conservative stage. With the rise of artificial intelligence technology in various fields, many scholars began to apply artificial intelligence technology to traditional Chinese medicine industry and made remarkable progress. This paper comprehensively summarizes the important role of artificial intelligence in the development of traditional Chinese medicine industry from various aspects, including new drug discovery, data mining, quality standardization and industry technology of traditional Chinese medicine. The limitations of artificial intelligence in these applications are also emphasized, including the lack of pharmacological research, database quality problems and the challenges brought by human-computer interaction. Nevertheless, the development of artificial intelligence has brought new opportunities and innovations to the modernization of traditional Chinese medicine. Integrating artificial intelligence technology into the comprehensive application of Chinese medicine industry is expected to overcome the major problems faced by traditional Chinese medicine industry and further promote the modernization of the whole traditional Chinese medicine industry.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38637024

RESUMO

BACKGROUND AND PURPOSE: Reliable preoperative visualization of facial nerve morphology and understanding the spatial relationship between the facial nerve and tumors in the parotid gland can help clinicians perform safe and effective surgeries. Hence, this study aimed to compare the image quality of extracranial facial nerves obtained by using double-echo steady state with water excitation (DESS-WE) and CISS sequences and evaluate their diagnostic efficacy in the localization of parotid tumors. MATERIALS AND METHODS: In total, 32 facial nerves of 16 healthy volunteers and 25 facial nerves of 25 patients with parotid tumors were included in this retrospective study. All participants underwent noncontrast-enhanced extracranial facial nerve MR imaging with DESS-WE and CISS with a 3T MR scanner equipped with a 64-channel head and neck coil. Image quality was subjectively evaluated by using a 5-point Likert scale by 2 radiologists. Inter- and intrarater agreements were assessed by using the Cohen κ coefficient. Receiver operating characteristic analysis was performed, and the diagnostic efficacies of DESS-WE and CISS images in localizing parotid tumors were calculated. RESULTS: For healthy volunteers (11 men and 5 women; median age, 26 years), image quality scores for CISS were significantly higher than those for DESS-WE for the discrimination of the temporofacial and cervicofacial trunks (both, P < .001). In patients with parotid tumors (12 men and 13 women; median age, 58 years), CISS performed better than DESS-WE in terms of visualizing the spatial relationship of the facial nerve to the tumor and diagnostic confidence (both, P < .001). Regarding the localization of parotid tumors, CISS showed excellent performance, comparable to that of DESS-WE (area under the curve, 0.981 versus 0.942, P = .1489). CONCLUSIONS: CISS achieved diagnostic performance comparable to DESS-WE in parotid tumor localization, with favorable image quality and more reliable morphologic visualization of the facial nerve.

18.
Comput Biol Med ; 172: 108261, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508056

RESUMO

Whole heart segmentation (WHS) has significant clinical value for cardiac anatomy, modeling, and analysis of cardiac function. This study aims to address the WHS accuracy on cardiac CT images, as well as the fast inference speed and low graphics processing unit (GPU) memory consumption required by practical clinical applications. Thus, we propose a multi-residual two-dimensional (2D) network integrating spatial correlation for WHS. The network performs slice-by-slice segmentation on three-dimensional cardiac CT images in a 2D encoder-decoder manner. In the network, a convolutional long short-term memory skip connection module is designed to perform spatial correlation feature extraction on the feature maps at different resolutions extracted by the sub-modules of the pre-trained ResNet-based encoder. Moreover, a decoder based on the multi-residual module is designed to analyze the extracted features from the perspectives of multi-scale and channel attention, thereby accurately delineating the various substructures of the heart. The proposed method is verified on a dataset of the multi-modality WHS challenge, an in-house WHS dataset, and a dataset of the abdominal organ segmentation challenge. The dice, Jaccard, average symmetric surface distance, Hausdorff distance, inference time, and maximum GPU memory of the WHS are 0.914, 0.843, 1.066 mm, 15.778 mm, 9.535 s, and 1905 MB, respectively. The proposed network has high accuracy, fast inference speed, minimal GPU memory consumption, strong robustness, and good generalization. It can be deployed to clinical practical applications for WHS and can be effectively extended and applied to other multi-organ segmentation fields. The source code is publicly available at https://github.com/nancy1984yan/MultiResNet-SC.


Assuntos
Coração , Software , Coração/diagnóstico por imagem , Tomografia Computadorizada por Raios X
19.
Quant Imaging Med Surg ; 14(8): 5983-6001, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39144026

RESUMO

Background: Programmed death ligand-1 (PD-L1) expression serves a predictive biomarker for the efficacy of immune checkpoint inhibitors (ICIs) in the treatment of patients with early-stage lung adenocarcinoma (LA). However, only a limited number of studies have explored the relationship between PD-L1 expression and spectral dual-layer detector-based computed tomography (SDCT) quantification, qualitative parameters, and clinical biomarkers. Therefore, this study was conducted to clarify this relationship in stage I LA and to develop a nomogram to assist in preoperative individualized identification of PD-L1-positive expression. Methods: We analyzed SDCT parameters and PD-L1 expression in patients diagnosed with invasive nonmucinous LA through postoperative pathology. Patients were categorized into PD-L1-positive and PD-L1-negative expression groups based on a threshold of 1%. A retrospective set (N=356) was used to develop and internally validate the radiological and biomarker features collected from predictive models. Univariate analysis was employed to reduce dimensionality, and logistic regression was used to establish a nomogram for predicting PD-L1 expression. The predictive performance of the model was evaluated using receiver operating characteristic (ROC) curves, and external validation was performed in an independent set (N=80). Results: The proportions of solid components and pleural indentations were higher in the PD-L1-positive group, as indicated by the computed tomography (CT) value, CT at 40 keV (CT40keV; a/v), electron density (ED; a/v), and thymidine kinase 1 (TK1) exhibiting a positive correlation with PD-L1 expression. In contrast, the effective atomic number (Zeff; a/v) showed a negative correlation with PD-L1 expression [r=-0.4266 (Zeff.a), -0.1131 (Zeff.v); P<0.05]. After univariate analysis, 18 parameters were found to be associated with PD-L1 expression. Multiple regression analysis was performed on significant parameters with an area under the curve (AUC) >0.6, and CT value [AUC =0.627; odds ratio (OR) =0.993; P=0.033], CT40keV.a (AUC =0.642; OR =1.006; P=0.025), arterial Zeff (Zeff.a) (AUC =0.756; OR =0.102; P<0.001), arterial ED (ED.a) (AUC =0.641; OR =1.158, P<0.001), venous ED (ED.v) (AUC =0.607; OR =0.864; P<0.001), TK1 (AUC =0.601; OR =1.245; P=0.026), and diameter of solid components (Dsolid) (AUC =0.632; OR =1.058; P=0.04) were found to be independent risk factors for PD-L1 expression in stage I LA. These seven predictive factors were integrated into the development of an SDCT parameter-clinical nomogram, which demonstrated satisfactory discrimination ability in the training set [AUC =0.853; 95% confidence interval (CI): 0.76-0.947], internal validation set (AUC =0.824; 95% CI: 0.775-0.874), and external validation set (AUC =0.825; 95% CI: 0.733-0.918). Decision curve analyses also revealed the highest net benefit for the nomogram across a broad threshold probability range (20-80%), with a clinical impact curve (CIC) indicating its clinical validity. Comparisons with other models demonstrated the superior discriminatory accuracy of the nomogram over any individual variable (all P values <0.05). Conclusions: Quantitative parameters derived from SDCT demonstrated the ability to predict for PD-L1 expression in early-stage LA, with Zeff.a being notably effective. The nomogram established in combination with TK1 showed excellent predictive performance and good calibration. This approach may facilitate the improved noninvasive prediction of PD-L1 expression.

20.
Comput Methods Programs Biomed ; 255: 108366, 2024 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-39126912

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors, after they reported methodological errors that compromise the accuracy of the results and the conclusion drawn from their findings. Specifically, the authors have reported an improvement in the accuracy of fractional flow reserve (FFR) estimation by improving the accuracy of coronary blood flow calculation in the resting state. This was later identified by the authors to be due to an error in their methodology when setting the CTA image grayscale threshold to 100 in the software MIMICS, which was reported to the journal. This value is too large, resulting in the coronary branches model with sizes between 1 and 1.7 mm not being displayed, and thus, overestimating the accuracy of the FFR estimation. Further evaluation of the method with a more appropriate parameter value led to a decrease in the accuracy of their FFR predictions from 91.74 % to 77.69 %, which is lower than Taylor's method (82.64 %). This contradicted the conclusion drawn from the paper. The Editors understand the significance of retracting a published paper and its potential impact on the authors, the readership, and the scientific community. However, the Editors firmly believe in upholding the highest standards of scientific rigor and accuracy, and therefore, a retraction of this paper is necessary to overcome the inaccurate information that has been disseminated and maintain the trust and credibility of the journal.

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