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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 ; : e2311477, 2024 Mar 30.
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 ; 59(2): 613-625, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37199241

RESUMO

BACKGROUND: Radiomics has been applied for assessing lymphovascular invasion (LVI) in patients with breast cancer. However, associations between features from peritumoral regions and the LVI status were not investigated. PURPOSE: To investigate the value of intra- and peritumoral radiomics for assessing LVI, and to develop a nomogram to assist in making treatment decisions. STUDY TYPE: Retrospective. POPULATION: Three hundred and sixteen patients were enrolled from two centers and divided into training (N = 165), internal validation (N = 83), and external validation (N = 68) cohorts. FIELD STRENGTH/SEQUENCE: 1.5 T and 3.0 T/dynamic contrast-enhanced (DCE) and diffusion-weighted imaging (DWI). ASSESSMENT: Radiomics features were extracted and selected based on intra- and peritumoral breast regions in two magnetic resonance imaging (MRI) sequences to create the multiparametric MRI combined radiomics signature (RS-DCE plus DWI). The clinical model was built with MRI-axillary lymph nodes (MRI ALN), MRI-reported peritumoral edema (MPE), and apparent diffusion coefficient (ADC). The nomogram was constructed with RS-DCE plus DWI, MRI ALN, MPE, and ADC. STATISTICAL TESTS: Intra- and interclass correlation coefficient analysis, Mann-Whitney U test, and least absolute shrinkage and selection operator regression were used for feature selection. Receiver operating characteristic and decision curve analyses were applied to compare performance of the RS-DCE plus DWI, clinical model, and nomogram. RESULTS: A total of 10 features were found to be associated with LVI, 3 from intra- and 7 from peritumoral areas. The nomogram showed good performance in the training (AUCs, nomogram vs. clinical model vs. RS-DCE plus DWI, 0.884 vs. 0.695 vs. 0.870), internal validation (AUCs, nomogram vs. clinical model vs. RS-DCE plus DWI, 0.813 vs. 0.695 vs. 0.794), and external validation (AUCs, nomogram vs. clinical model vs. RS-DCE plus DWI, 0.862 vs. 0.601 vs. 0.849) cohorts. DATA CONCLUSION: The constructed preoperative nomogram might effectively assess LVI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Radiômica , Estudos Retrospectivos , Imagem de Difusão por Ressonância Magnética , Mama , Imageamento por Ressonância Magnética
6.
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.

7.
Eur Radiol ; 34(3): 1667-1676, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37672057

RESUMO

OBJECTIVES: The study aims to evaluate the incremental predictive value of pericarotid fat density (PFD) on head and neck computed tomography angiography (CTA) for the obstructive coronary artery disease (CAD) (≥ 50% stenosis) relative to a clinical risk model (Framingham risk score (FRS)) and the degree of carotid artery stenosis and plaque type in acute ischemic stroke (AIS) or transient ischemic attack (TIA) patients without a known history of CAD. METHODS: In a cohort of 134 consecutive stable patients diagnosed with AIS or TIA undergoing head and neck CTA between January 2010 and December 2021, pericarotid adipose tissue density (PFD) was quantified using a dedicated software. We collected demographic and clinical data, assessed the risk of CAD using the FRS, and analyzed coronary and carotid artery CTA images. Univariate and multivariate logistic regression analyses were performed to assess associations between FRS, PFD, CTA variables, and obstructive CAD risk. Four prediction models were established to evaluate the incremental predictive value of PFD relative to FRS, stenosis degree, and plaque types. Receiver operating characteristic (ROC) curves were generated, and the areas under the curves (AUC) were compared. RESULTS: Increasing FRS, stenosis degree, and PFD values were positively correlated with obstructive CAD (all p < 0.05). In the predictive models for obstructive CAD, the model incorporating carotid stenosis exhibited superior predictive performance compared to FRS alone (p < 0.05). Moreover, the predictive model integrating PFD demonstrated enhanced performance and yielded the highest AUC of the receiver operator characteristic curve (AUC = 0.783), with sensitivity and specificity values of 86.89% and 65.75%, respectively. CONCLUSION: CTA-derived PFD measurements offer supplementary predictive value for obstructive CAD beyond FRS and stenosis, thereby facilitating improved risk stratification of TIA or stroke patients without a history of CAD history. CLINICAL RELEVANCE STATEMENT: CTA-derived PFD provides incremental predictive value for obstructive coronary artery disease in acute ischemic stroke or transient ischemic attack patients without CAD history, beyond Framingham risk score and carotid artery stenosis degree, improving risk stratification. KEY POINTS: • Pericarotid fat density is associated with obstructive coronary artery disease in acute ischemic stroke or transient ischemic attack patients. • Higher pericarotid fat density corresponds to an increased risk of obstructive coronary artery disease. • Estimation of pericarotid fat density using computed tomography angiography imparts additional predictive value for obstructive CAD in risk stratification of acute ischemic stroke or transient ischemic attack patients.


Assuntos
Estenose das Carótidas , Doença da Artéria Coronariana , Estenose Coronária , Ataque Isquêmico Transitório , AVC Isquêmico , Placa Aterosclerótica , Humanos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/diagnóstico por imagem , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Constrição Patológica , Angiografia Coronária/métodos , Valor Preditivo dos Testes , Angiografia por Tomografia Computadorizada/métodos , Fatores de Risco , Tecido Adiposo/diagnóstico por imagem
8.
Phys Chem Chem Phys ; 2024 Jul 17.
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.

9.
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.

10.
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
11.
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.

12.
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
13.
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.

14.
Chem Soc Rev ; 52(6): 2193-2237, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36806286

RESUMO

Electrochemical C-N coupling reactions based on abundant small molecules (such as CO2 and N2) have attracted increasing attention as a new "green synthetic strategy" for the synthesis of organonitrogen compounds, which have been widely used in organic synthesis, materials chemistry, and biochemistry. The traditional technology employed for the synthesis of organonitrogen compounds containing C-N bonds often requires the addition of metal reagents or oxidants under harsh conditions with high energy consumption and environmental concerns. By contrast, electrosynthesis avoids the use of other reducing agents or oxidants by utilizing "electrons", which are the cleanest "reagent" and can reduce the generation of by-products, consistent with the atomic economy and green chemistry. In this study, we present a comprehensive review on the electrosynthesis of high value-added organonitrogens from the abundant CO2 and nitrogenous small molecules (N2, NO, NO2-, NO3-, NH3, etc.) via the C-N coupling reaction. The associated fundamental concepts, theoretical models, emerging electrocatalysts, and value-added target products, together with the current challenges and future opportunities are discussed. This critical review will greatly increase the understanding of electrochemical C-N coupling reactions, and thus attract research interest in the fixation of carbon and nitrogen.

15.
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.

16.
Ann Surg ; 278(1): e68-e79, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35781511

RESUMO

OBJECTIVE: To develop an imaging-derived biomarker for prediction of overall survival (OS) of pancreatic cancer by analyzing preoperative multiphase contrast-enhanced computed topography (CECT) using deep learning. BACKGROUND: Exploiting prognostic biomarkers for guiding neoadjuvant and adjuvant treatment decisions may potentially improve outcomes in patients with resectable pancreatic cancer. METHODS: This multicenter, retrospective study included 1516 patients with resected pancreatic ductal adenocarcinoma (PDAC) from 5 centers located in China. The discovery cohort (n=763), which included preoperative multiphase CECT scans and OS data from 2 centers, was used to construct a fully automated imaging-derived prognostic biomarker-DeepCT-PDAC-by training scalable deep segmentation and prognostic models (via self-learning) to comprehensively model the tumor-anatomy spatial relations and their appearance dynamics in multiphase CECT for OS prediction. The marker was independently tested using internal (n=574) and external validation cohorts (n=179, 3 centers) to evaluate its performance, robustness, and clinical usefulness. RESULTS: Preoperatively, DeepCT-PDAC was the strongest predictor of OS in both internal and external validation cohorts [hazard ratio (HR) for high versus low risk 2.03, 95% confidence interval (CI): 1.50-2.75; HR: 2.47, CI: 1.35-4.53] in a multivariable analysis. Postoperatively, DeepCT-PDAC remained significant in both cohorts (HR: 2.49, CI: 1.89-3.28; HR: 2.15, CI: 1.14-4.05) after adjustment for potential confounders. For margin-negative patients, adjuvant chemoradiotherapy was associated with improved OS in the subgroup with DeepCT-PDAC low risk (HR: 0.35, CI: 0.19-0.64), but did not affect OS in the subgroup with high risk. CONCLUSIONS: Deep learning-based CT imaging-derived biomarker enabled the objective and unbiased OS prediction for patients with resectable PDAC. This marker is applicable across hospitals, imaging protocols, and treatments, and has the potential to tailor neoadjuvant and adjuvant treatments at the individual level.


Assuntos
Carcinoma Ductal Pancreático , Aprendizado Profundo , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Prognóstico , Neoplasias Pancreáticas
17.
Small ; 19(25): e2301164, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919943

RESUMO

In recent years, growing concerns regarding energy efficiency and heat mitigation, along with the critical goal of carbon neutrality, have drawn human attention to the zero-energy-consumption cooling technique. Passive daytime radiative cooling (PDRC) can be an invaluable tool for combating climate change by dispersing ambient heat directly into outer space instead of just transferring it across the surface. Although significant progress has been made in cooling mechanisms, materials design, and application exploration, PDRC faces challenges regarding functionality, durability, and commercialization. Herein, a silica nanofiber aerogels (SNAs) functionalized poly(vinylidene fluoride-co-hexafluoropropene) (P(VDF-HFP)) membrane (SFP membrane), inspired by constructional engineering is constructed. As-prepared membranes with flexible network structure combined hierarchical structure design and practicability principal. As the host material for thermal comfort management (TCM) and versatile protection, the SFP membrane features a large surface area, porous structure, and a robust skeleton that can render excellent mechanical properties. Importantly, the SFP membrane can keep exceptional solar reflectivity (0.95) and strong mid-infrared emittance (0.98) drop the temperature to 12.5 °C below ambient and 96 W m-2 cooling power under typical solar intensities over 910 W m-2 . This work provides a promising avenue for high performance aerogel membranes that can be created for use in a wide variety of applications.

18.
BMC Cancer ; 23(1): 91, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36703132

RESUMO

OBJECTIVES: To evaluate the discriminatory capability of spectral CT-based radiomics to distinguish benign from malignant solitary pulmonary solid nodules (SPSNs). MATERIALS AND METHODS: A retrospective study was performed including 242 patients with SPSNs who underwent contrast-enhanced dual-layer Spectral Detector CT (SDCT) examination within one month before surgery in our hospital, which were randomly divided into training and testing datasets with a ratio of 7:3. Regions of interest (ROIs) based on 40-65 keV images of arterial phase (AP), venous phases (VP), and 120kVp of SDCT were delineated, and radiomics features were extracted. Then the optimal radiomics-based score in identifying SPSNs was calculated and selected for building radiomics-based model. The conventional model was developed based on significant clinical characteristics and spectral quantitative parameters, subsequently, the integrated model combining radiomics-based model and conventional model was established. The performance of three models was evaluated with discrimination, calibration, and clinical application. RESULTS: The 65 keV radiomics-based scores of AP and VP had the optimal performance in distinguishing benign from malignant SPSNs (AUC65keV-AP = 0.92, AUC65keV-VP = 0.88). The diagnostic efficiency of radiomics-based model (AUC = 0.96) based on 65 keV images of AP and VP outperformed conventional model (AUC = 0.86) in the identification of SPSNs, and that of integrated model (AUC = 0.97) was slightly further improved. Evaluation of three models showed the potential for generalizability. CONCLUSIONS: Among the 40-65 keV radiomics-based scores based on SDCT, 65 keV radiomics-based score had the optimal performance in distinguishing benign from malignant SPSNs. The integrated model combining radiomics-based model based on 65 keV images of AP and VP with Zeff-AP was significantly superior to conventional model in the discrimination of SPSNs.


Assuntos
Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/patologia
19.
J Magn Reson Imaging ; 58(6): 1815-1823, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36988474

RESUMO

BACKGROUND: There are known cardiac manifestations of HIV, but the findings in asymptomatic subjects are still not fully explored. PURPOSE: To evaluate for the presence of subclinical myocardial injury in asymptomatic people living with human immunodeficiency virus (PLWH) by cardiac MRI and to explore the possible association between subclinical myocardial injury and HIV-related clinical characteristics. STUDY TYPE: Cross-sectional. POPULATION: A total of 80 asymptomatic PLWH (age: 53 years [47-56 years]; 90% male) and 50 age- and sex-matched healthy participants. FIELD STRENGTH/SEQUENCE: A 3-T, cine sequence, T1, T2, and T2* mapping. ASSESSMENT: Function analysis was derived from short axis, two-, three-, and four-chamber cine images by feature tracking. Regions of interest were manually selected in the midventricular septum T1, T2, and T2* mapping sequences. PLWH were evaluated for T1 increment (△T1 mapping = native T1 - cutoff values) and HIV-related clinical characteristics, particularly the nadir CD4 count. And PLWH were stratified into two groups according to the cutoff value of native T1: elevated native T1 and normal. STATISTICAL TESTS: T test, Wilcoxon rank-sum test, Chi-square test, Spearman rank correlation, and logistic regression. P <0.05 indicated statistical significance. RESULTS: Asymptomatic PLWH revealed significantly higher native myocardial T1 values (1241 ± 29 msec vs. 1189 ± 21 msec), T2 values (40.7 ± 1.5 msec vs. 37.9 ± 1.4 msec), and lower LVGRS (30.2% ± 6.2% vs. 35.8% ± 6.4%), LVGCS (-18.0% ± 2.5% vs. -19.5% ± 2.0%), and LVGLS (-16.0% ± 3.8% vs. -17.9% ± 2.6%) but showed no difference in T2* values (17.3 msec [16.3-19.1 msec] vs. 18.3 msec [16.5-19.3 msec], P = 0.201). A negative correlation between the native T1 increment in PLWH with subclinical myocardial injury and the nadir CD4 count (u = -0.316). Nadir CD4 count <500 cells/mm3 was associated with higher odds of elevated native T1 myocardial values (odds ratio, 6.12 [95% CI, 1.07-34.91]) in PLWH. DATA CONCLUSION: Subclinical myocardial inflammation and dysfunction were present in asymptomatic PLWH, and a lower nadir CD4 count may be a risk factor for subclinical myocardial injury. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: Stage 2.


Assuntos
Infecções por HIV , Traumatismos Cardíacos , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , HIV , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Coração/diagnóstico por imagem , Miocárdio , Infecções por HIV/complicações , Imagem Cinética por Ressonância Magnética , Valor Preditivo dos Testes
20.
J Magn Reson Imaging ; 58(5): 1533-1541, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36912379

RESUMO

BACKGROUND: Anthracyclines are known to be associated with chemotherapy-induced cardiotoxicity. Limited data focus on dynamic myocardial injury during the course of chemotherapy in patients with breast cancer. PURPOSE: To investigate the variation of tissue characterization and myocardial deformation derived by cardiac MRI during anthracycline chemotherapy. STUDY TYPE: Prospective. POPULATION: Fifty-eight female breast cancer patients (mean age: 52.82 ± 2.61 years) were enrolled. FIELD STRENGTH/SEQUENCE: A 3.0-T, cardiac MRI including cine balanced steady-state free precession, a modified Looker-Locker inversion recovery (MOLLI), and a fast spin echo (FSE) T2-weighted sequences were performed. ASSESSMENT: Cardiac MRI was performed baseline and after two, four, and six cycles of chemotherapy. Assessment of global longitudinal strain (GLS), global circumstance strain (GCS), global radial strain (GRS), and strain rate (GLS-s, GCS-s, GRS-s) and T1, T2 and T2* were accomplished by CVI42. The anthracycline dose and risk factors were also collected before each cardiac MRI. STATISTICAL TESTS: Analysis of variance (ANOVA) for repeated measures was used to compare the changes in LVEF cardiac function, strain and T1/T2/T2* parameters over time. Pearson correlation analyses were performed to estimate the potential associations between differences in myocardial characteristics (∆) and the chemotherapy cycle. A P value <0.05 was considered statistically significant. RESULTS: LVEF was not significantly different from pretreatment MRI regarding each cycle of chemotherapy (P = 0.54). Compared with baseline, patients had significantly lower GLS (-15.85% ± 0.83%, -14.50% ± 0.88%, -12.34% ± 1.01% vs. -18.82% ± 0.92%) and GLS-s (-0.71% ± 0.07%, -0.65% ± 0.05%, -0.64% ± 0.04% vs. -0.95 ± 0.06%) and increased T2 values (57.21 ± 4.27 msec, 58.60 ± 3.93 msec, 58.10 ± 3.17 msec vs. 43.88 ± 3.28 msec) at two, four and six cycles of chemotherapy treatment. ∆GLS and ∆GLS-s were significantly associated with the chemotherapy cycle (correlation coefficients for GLS = 0.75, GLS-s = 0.75). DATA CONCLUSION: Cardiac MRI can precisely detect the dynamic changes of anthracycline-induced subclinical myocardial injury that is represented as a gradually decrease in GLS and GLS-s. These parameters may provide new insight for monitoring risk and therapy in patients with breast cancer. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 1.


Assuntos
Neoplasias da Mama , Traumatismos Cardíacos , Humanos , Feminino , Pessoa de Meia-Idade , Antraciclinas/efeitos adversos , Estudos Prospectivos , Cardiotoxicidade/diagnóstico por imagem , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/etiologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Imageamento por Ressonância Magnética/efeitos adversos , Função Ventricular Esquerda , Volume Sistólico
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