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1.
Artigo em Inglês | MEDLINE | ID: mdl-39300615

RESUMO

Passive daytime radiative cooling (PDRC) textiles hold substantial potential for localized outdoor cooling of the human body without additional energy consumption, but their limited multifunctional integration severely hinders their practical application. Herein, aluminum-doped zinc oxide (AZO) nanoparticles were purposefully introduced into poly(vinylidene fluoride) (PVDF) nanofibers via a facile electrospinning process, forming a large-scale and flexible PDRC textile with the desired antibacterial, UV-shielding, and self-cleaning capabilities. These prepared PDRC textiles present a weighted sunlight reflection rate of 92.3% and a weighted emissivity of 89.5% in the mid-infrared region. Furthermore, outdoor tests with an average solar intensity of ∼715 W/m2 demonstrated that a skin simulator temperature could be cooled by ∼16.1 °C below the ambient temperature, outperforming cotton fabric by ∼6.3 °C. Owing to the outstanding photocatalytic properties of the AZO nanoparticles, these prepared PVDF textiles exhibit antibacterial properties (Escherichia coli: 99.99%), UV-shielding performance (UPF > 50+), and superior self-cleaning capabilities, providing a cost-effective and eco-friendly avenue for daytime personal thermal management.

2.
J Nanobiotechnology ; 22(1): 583, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304945

RESUMO

Kidney diseases represent a diverse range of conditions that compromise renal function and structure which characterized by a progressive deterioration of kidney function, may ultimately necessitate dialysis or kidney transplantation as end-stage treatment options. This review explores the complex landscape of kidney diseases, highlighting the limitations of existing treatments and the pressing need for innovative strategies. The paper delves into the role of extracellular vesicles (EVs) as emerging biomarkers and therapeutic agents in the context of kidney pathophysiology. Urinary extracellular vesicles (uEVs), in particular, offer a non-invasive means of assessing renal injury and monitoring disease progression. Additionally, mesenchymal stem cell-derived EVs (MSC-EVs) are examined for their immunomodulatory and tissue repair capabilities, presenting a promising avenue for novel therapeutic interventions. And discusses the potential of engineering EVs to enhance their targeting and therapeutic efficacy. This paper systematically integrates the latest research findings and aims to provide a comprehensive overview of the role of EVs in kidney disease, providing cutting-edge insights into their potential as a diagnostic and therapeutic tool.


Assuntos
Biomarcadores , Vesículas Extracelulares , Nefropatias , Células-Tronco Mesenquimais , Vesículas Extracelulares/metabolismo , Humanos , Nefropatias/metabolismo , Animais , Células-Tronco Mesenquimais/metabolismo , Biomarcadores/metabolismo , Rim/metabolismo
3.
Int Ophthalmol ; 44(1): 367, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235629

RESUMO

PURPOSE: Crouzon syndrome is a congenital genetic disease caused by mutations of the FGFR2 gene on chromosome 10. It is usually inherited in an autosomal dominant pattern and is one of the most common types of craniosynostosis syndromes. This article focuses on the ophthalmology-related aspects of Crouzon syndrome in order to help diagnose and develop personalized treatment plans. METHODS: A combined systematic search of PubMed electronic database by using Boolean operators AND and OR was conducted, choosing the following keywords: "Crouzon", "craniosynostosis", " eye ", " oculus ", " ocular ", " ophthalmic ", " ophthalmologic ", " ophthalmology ", " globe ", " orbit ", " exophthalmos ", " exorbitism ", " keratopathy ", " visual " etc. After the initial screening of these articles, repetitive literatures were excluded. RESULTS: 47 articles were selected. This article introduces the ocular manifestations, possible pathogenesis and treatment progress in Crouzon syndrome. CONCLUSIONS: The incidence of ocular abnormalities in Crouzon syndrome is very high, such as shallow orbits, exophthalmos, hypertelorism, exposure keratopathy, strabismus, optic neuropathy, ametropia, glaucoma, etc. The pathogenesis of these ocular abnormalities is related to orbital deformities. Most of the treatments are aimed at compensating the abnormal anatomic structure at present.


Assuntos
Disostose Craniofacial , Humanos , Disostose Craniofacial/diagnóstico , Disostose Craniofacial/genética , Oftalmopatias/diagnóstico , Oftalmopatias/terapia , Oftalmopatias/etiologia , Anormalidades do Olho/diagnóstico , Anormalidades do Olho/terapia , Anormalidades do Olho/genética , Mutação
4.
Front Surg ; 11: 1418314, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39301169

RESUMO

Background: Re-resection is recommended for patients with incidental gallbladder carcinoma (iGBC) at T1b stage and above. It is unclear whether continuation of laparoscopic re-resection (CLR) for patients with intraoperatively detected iGBC (IDiGBC) is more beneficial to short- and long-term clinical outcomes than with conversion to radical extensive-resection (RER). Methods: This single-centre, retrospective cohort study of patients with iGBC was conducted between June 2006 and August 2021. Patients who underwent immediate reresection for T1b or higher ID-iGBC were enrolled. Propensity score matching (PSM) was used to match the two groups (CLR and RER) of patients, and differences in clinical outcomes before and after matching were analyzed. Result: A total of 102 patients with ID-iGBC were included in this study. 58 patients underwent CLR, and 44 underwent RER. After 1:1 propensity score matching, 56 patients were matched to all baselines. Patients in the RER group had a lower total postoperative complication rate, lower pulmonary infection rate, and shorter operation time than those in the CLR group did. Kaplan-Meier analysis showed that the overall survival rate of patients who underwent CLR was significantly lower than that of patients who underwent RER. Multivariate analysis showed that CLR, advanced T stage, lymph node positivity, and the occurrence of postoperative ascites were adverse prognostic factors for the overall survival of patients. Conclusion: Patients with ID-iGBC who underwent RER had fewer perioperative complications and a better prognosis than those who underwent CLR. For patients with ID-iGBC, conversion to radical extensive-resection appears to be a better choice.

6.
BMC Public Health ; 24(1): 2475, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261784

RESUMO

BACKGROUND: With global climate change, the health threats of ambient high temperature have received widespread attention. However, latest spatio-temporal patterns of the non-communicable diseases (NCDs) burden attributable to high temperature have not been systematically reported. We aimed to analyze vulnerable areas and populations based on a detailed profile for the NCDs burden attributable to high temperature globally. METHODS: We obtained data from the Global Burden of Diseases (GBD) Study (2019) to describe the temporal and spatial patterns of NCDs burden attributable to high temperature globally from 1990-2019. Then we analyzed the differences by region, sex, and socio-demographic index (SDI). Finally, the age­period­cohort (APC) model was utilized to explore the age, period, and cohort effects of NCDs mortality caused by high temperature. RESULTS: In 2019, the number of deaths and Disability-adjusted life years (DALYs) from high-temperature-related NCDs was about 150,000 and 3.4 million globally, of which about 70% were in South Asia and North Africa and Middle East, and the burden was higher in men. Among 204 countries and territories, the highest age-standardized mortality rate (ASMR) and age-standardized DALY rate (ASDR) were observed in Oman and United Arab Emirates, respectively. The global burden showed an upward trend from 1990 to 2019, with an EAPC of 3.66 (95%CI: 3.14-4.18) for ASMR and 3.68 (95%CI: 3.16-4.21) for ASDR. Cardiovascular diseases were the main contributors to the global burden of high-temperature-related NCDs in 2019. The age and period effect in APC model showed an increasing trend globally. There was a significant negative correlation between SDI and both ASMR (r = -0.17) and ASDR (r = -0.20) from 1990 to 2019. CONCLUSION: There was an increasing trend of the global burden of high-temperature-related NCDs. The burden was likely to be higher in males and the elderly, as well as in countries and regions with less economically and socially developed and in tropical climates. Surveillance and prevention measures should be implemented with a focus on these vulnerable areas and susceptible populations.


Assuntos
Mudança Climática , Carga Global da Doença , Saúde Global , Temperatura Alta , Doenças não Transmissíveis , Humanos , Doenças não Transmissíveis/mortalidade , Doenças não Transmissíveis/epidemiologia , Masculino , Feminino , Carga Global da Doença/tendências , Pessoa de Meia-Idade , Idoso , Adulto , Saúde Global/estatística & dados numéricos , Temperatura Alta/efeitos adversos , Adulto Jovem , Adolescente , Anos de Vida Ajustados por Deficiência , Criança , Pré-Escolar , Lactente , Idoso de 80 Anos ou mais , Efeitos Psicossociais da Doença
7.
Front Immunol ; 15: 1398299, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39267744

RESUMO

Background: Obesity represents a significant risk factor for the development of metabolic abnormalities. However, it is not inevitable that all individuals with obesity will develop these disorders. Selenium has been demonstrated to play a role in maintaining metabolic homeostasis in vivo, with the ability to regulate relevant signaling pathways involved in glucose and lipid metabolism processes. Previous studies have indicated that selenium concentrations in obese individuals are higher than those reported in the general population. These findings the question of whether altered selenium concentrations may act as important triggers for accelerating metabolic imbalances in the obese population. The aim of this study was to examine the potential correlation between serum selenium concentrations and the risk of developing metabolic abnormalities in individuals with obesity. Methods: The present study included 6,125 participants from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) who were aged between 20 and 80 years, with a body mass index (BMI) of 30 kg/m2 or greater, and met the inclusion and exclusion criteria. Weighted generalized linear regression analyses were conducted to evaluate the associations between serum selenium concentrations and the conversion of metabolically healthy obesity (MHO) to metabolically unhealthy obesity (MUO). A generalized additive model (GAM) and a two-piecewise linear regression model were employed to investigate the saturation threshold effect between selenium and MUO. The correlation between different selenium concentration intervals and metabolic diseases was evaluated by categorizing selenium concentrations according to the saturation threshold. Furthermore, this study investigated the correlation between serum selenium and lipid concentrations in obese females and between serum selenium and blood pressure in obese males. Results: The weighted prevalence of MUO in the study population was 48.35%. After rigorous adjustment for sociodemographic, physical, and laboratory test covariates, the weighted odds ratio (OR) of MUO increased by 44% for every 1 µM increase (approximately 78.74 µg) in the serum selenium concentration (weighted OR=1.44; 95% CI=1.09 - 1.91; P=0.018). Second, GAM analysis and saturation threshold analyses revealed an inverted U-shaped relationship between serum selenium and metabolic abnormalities in males, with a corresponding inflection point (K) of 2.82 µM. When the serum selenium concentration was below the K-value, the effects of serum selenium were mainly on blood pressure, especially diastolic blood pressure (DBP) (weighted ß: 3.34; 95% CI= 0.25 - 6.44; P=0.038). Conversely, the correlation between the serum selenium concentrations and metabolic homeostasis imbalance in females was linear. When the selenium concentration exceeded 2.12 µM, the increase in selenium content was accompanied by increases in total cholesterol (TC, weighted ß=0.54, 95% CI=0.32 - 0.76; P=0.000) and triglyceride (TG, weighted ß=0.51, 95% CI=0.27 - 0.75; P=0.000) concentrations. Conclusions: The findings of our study indicate that selenium supplementation strategies for individuals with obesity should be tailored to the sex of the individual. In females, serum selenium concentration above the saturation threshold primarily facilitates the transition from MHO to MUO by influencing alterations in serum lipid metabolism. Maintaining selenium concentrations below the threshold levels is highly important for preventing the conversion of MHO to MUO. In males, serum selenium concentrations above the threshold were found to be effective in preventing an elevation in blood pressure, particularly in improving systolic blood pressure (SBP). Nevertheless, serum selenium concentrations below the threshold are linked to an increased risk of hypertension in obese individuals, particularly those with elevated diastolic blood pressure (DBP). Further research is needed to elucidate the optimal serum selenium concentration that exerts deleterious effects on blood pressure.


Assuntos
Doenças Metabólicas , Inquéritos Nutricionais , Selênio , Humanos , Selênio/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Transversais , Estudos Retrospectivos , Idoso , Estados Unidos/epidemiologia , Doenças Metabólicas/sangue , Doenças Metabólicas/epidemiologia , Obesidade Metabolicamente Benigna/sangue , Adulto Jovem , Idoso de 80 Anos ou mais , Obesidade/sangue , Índice de Massa Corporal , Fatores de Risco
8.
ACS Nano ; 18(37): 25522-25534, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39228064

RESUMO

Piezoelectric-assisted photocatalysis has a huge potential in solving the energy shortage and environmental pollution problems, and imaging their detailed charge-transfer process can provide in-depth understanding for the development of high-active piezo-photocatalysts; however, it is still challenging. Herein, topotactic heterostructures of TiO2@BaTiO3 (TO@BTO-S) were constructed by the epitaxial growth of ferroelectric BaTiO3 mesocrystals on TiO2-{001} facets, resulting in a ferroelectric photocatalyst with a polarization orientation on the surface. Notably, the photoinduced charge transfer in ferroelectric TiO2@BaTiO3 was accurately monitored and directly visualized at the single-particle level by the advanced photoluminescence (PL) imaging microscopy systems. The longer PL lifetime of TO@BTO-S demonstrated the efficient charge separation caused by a built-in electric field, which is constructed by the polarization orientation of BaTiO3 mesocrystals. Therefore, the TO@BTO-S heterostructure exhibits efficient piezoelectric-assisted photocatalytic pure water splitting, which is 290 times higher than photocatalysis. This work revealed time/spatial-resolved photoinduced charge transfer in piezoelectric assistance photocatalysts at the single-particle level and demonstrated the great role of polarization orientation in promoting charge transfer for photocatalysis.

9.
Cell Signal ; 124: 111408, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39270917

RESUMO

Hepatic gluconeogenesis plays a crucial role in maintaining glucose homeostasis and serves as a potential therapeutic target for type 2 diabetes, while its underlying mechanisms are not fully understood. This study elucidates the role of the deubiquitinase OTU domain-containing ubiquitin aldehyde binding protein 1 (OTUB1) in gluconeogenesis. We found that hepatic OTUB1 expression is reduced in both db/db mice and patients with type 2 diabetes. Deletion of hepatic OTUB1 significantly elevates fasting blood glucose levels and increases the expression of key gluconeogenic genes. Conversely, overexpression of OTUB1 in hepatocytes mitigates diabetic hyperglycemia and enhances insulin sensitivity. It is known that the tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein ß (YWHAB) functions as an inhibitor of hepatic gluconeogenesis by interacting with forkhead box protein O (FOXO1) and glucagon receptor (GPCR), but its own modification mechanism remains unclear. Our findings indicate that OTUB1 interacts with YWHAB and deubiquitinates it through a catalytic process, which in turn suppresses gluconeogenesis. Therefore, OTUB1 plays a pivotal role in inhibiting hepatic gluconeogenesis, highlighting its potential as a therapeutic target for type 2 diabetes.

10.
Front Oncol ; 14: 1437978, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39267826

RESUMO

Background: Recent evidence indicates that inflammation plays a major role in the pathogenesis and progression of CCA. This meta-analysis seeks to evaluate the prognostic implications of preoperative inflammatory markers, specifically NLR, PLR, and LMR, in patients with eCCA. By focusing on these preoperative biomarkers, this study aims to provide valuable insights into their prognostic value and potential utility in clinical practice. Methods: For this analysis, comprehensive searches were conducted in PubMed, Embase, and Web of Science databases from inception to May 2024. The primary outcomes of interest focused on the association between the levels of NLR, PLR, and LMR and the prognosis of eCCA patients. Statistical analyses were conducted using STATA 17.0 software. Results: The meta-analysis, involving 20 retrospective studies with 5553 participants, revealed significant correlations between preoperative biomarkers and the prognosis of eCCA patients. Elevated NLR, PLR, and decreased LMR levels were extensively studied regarding overall survival (OS) in eCCA patients. Elevated NLR was an independent predictor of poor OS (HR 1.86, p < 0.001), similar to elevated PLR (HR 1.76, p < 0.001), while decreased LMR predicted poor OS (HR 2.16, p < 0.001). Subgroup analyses based on eCCA subtypes and curative surgery status showed consistent results. Conclusions: In conclusion, our study emphasizes the clinical significance of assessing NLR, PLR, and LMR preoperatively to predict patient prognosis. Elevated NLR and PLR values, along with decreased LMR values, were linked to poorer overall survival (OS). Large-scale prospective cohort studies are required to confirm their independent prognostic value in eCCA. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42024551031.

11.
World J Clin Cases ; 12(22): 5131-5139, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39109012

RESUMO

BACKGROUND: Sotos syndrome is an autosomal dominant disorder, whereas attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition. This report aimed to summarize the clinical and genetic features of a pediatric case of Soros syndrome and ADHD in a child exhibiting precocious puberty. CASE SUMMARY: The patient presented with accelerated growth and advanced skeletal maturation; however, she lacked any distinct facial characteristics related to specific genetic disorders. Genetic analyses revealed a paternally inherited heterozygous synonymous mutation [c.4605C>T (p.Arg1535Arg)]. Functional analyses suggested that this mutation may disrupt splicing, and bioinformatics analyses predicted that this mutation was likely pathogenic. After an initial diagnosis of Sotos syndrome, the patient was diagnosed with ADHD during the follow-up period at the age of 8 years and 7 months. CONCLUSION: The potential for comorbid ADHD in Sotos syndrome patients should be considered to avoid the risk of a missed diagnosis.

12.
World J Gastrointest Surg ; 16(7): 2242-2254, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39087095

RESUMO

BACKGROUND: The high incidence and mortality of gastric cancer (GC) pose a significant threat to human life and health, and it has become an important public health challenge in China. Body weight loss is a common complication after surgical treatment in patients with GC and is associated with poor prognosis and GC recurrence. However, current attention to postoperative weight change in GC patients remains insufficient, and the descriptions of postoperative weight change and its influencing factors are also different. AIM: To investigate body weight changes in patients with GC within 6 mo after gastrectomy and identify factors that influence dynamic body weight changes. METHODS: We conducted a prospective longitudinal study of 121 patients with GC and collected data before (T0) and 1 (T1), 3 (T2), and 6 (T3) mo after gastrectomy using a general data questionnaire, psychological distress thermometer, and body weight measurements. The general estimation equation (GEE) was used to analyze the dynamic trends of body weight changes and factors that influence body weight changes in patients with GC within 6 mo of gastrectomy. RESULTS: The median weight loss at T1, T2, and T3 was 7.29% (2.84%, 9.40%), 11.11% (7.64%, 14.91%), and 14.75% (8.80%, 19.84%), respectively. The GEE results showed that preoperative body mass index (BMI), significant psychological distress, religious beliefs, and sex were risk factors for weight loss in patients with GC within 6 mo after gastrectomy (P < 0.05). Compared with preoperative low-weight patients, preoperative obese patients were more likely to have weight loss (ß = 14.685, P < 0.001). Furthermore, patients with significant psychological distress were more likely to lose weight than those without (ß = 2.490, P < 0.001), and religious patients were less likely to lose weight 6 mo after gastrectomy than those without religious beliefs (ß = -6.844, P = 0.001). Compared to female patients, male patients were more likely to experience weight loss 6 mo after gastrectomy (ß = 4.262, P = 0.038). CONCLUSION: Male patients with GC with high preoperative BMI, significant psychological distress, and no religious beliefs are more likely to lose weight after gastrectomy.

13.
Food Chem ; 460(Pt 3): 140580, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142197

RESUMO

It is imperative to unravel the dynamic variation of volatile components of vine tea during processing to provide guidance for tea quality evaluation. In this study, the dynamic changes of volatile compounds of vine tea during processing were characterized by GC-IMS and HS-SPME/GC-MS. As a result, 103 volatile compounds were characterized by the two technologies with three overlapped ones. The random forest approach was employed to develop the models and explore key volatile compounds. 23 key compounds were explored, among which 13 were derived from GC-IMS and ten were from HS-SPME/GC-MS. Moreover, the area under the receiver operating characteristics curve with 100 cross validations by the pair-wised models were all 1 for the established models. Furthermore, the primary aroma formation mechanism for the key volatile compounds were mainly involved in fatty acid and amino acid metabolism. Besides, this study provides a theoretical support for directed processing and quality control of vine tea.


Assuntos
Camellia sinensis , Cromatografia Gasosa-Espectrometria de Massas , Aprendizado de Máquina , Odorantes , Microextração em Fase Sólida , Chá , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/análise , Microextração em Fase Sólida/métodos , Chá/química , Camellia sinensis/química , Odorantes/análise , Manipulação de Alimentos , Algoritmos , Espectrometria de Mobilidade Iônica/métodos
14.
ACS Appl Mater Interfaces ; 16(35): 45901-45916, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39169670

RESUMO

Immune checkpoint blockade (ICB) therapy, while showing promise in various cancers, exhibits limited effectiveness in hepatic carcinoma due to the tumor's immunosuppressive microenvironment (TME) and challenges associated with immune cell infiltration. Efforts to transform the "cold" TME into an "inflamed" state, notably through chemo-immunotherapy, have sparked interest due to their potential to induce immunogenic cell death and augment the infiltration of cytotoxic T lymphocytes (CTLs). Nonetheless, the efficacy of chemo-immunotherapy is often compromised by suboptimal pharmacokinetics, poor tumor accumulation, and off-target toxicity. Herein, in response, we introduce an innovative, milder thermal therapeutic approach leveraging gold nano frameworks with mesopores for the targeted delivery of the immunostimulant imiquimod and NIR-II photothermal therapy. This strategy employs targeted molecule modifications to ensure precise tumor targeting, guided by photoacoustic imaging. Subsequent to mild thermal treatment, there is a release of immunogenic proteins (CRT and HSP90), enhancing tumor immunogenicity. Assisted by imiquimod, substantial CTL infiltration occurs, accompanied by pro-inflammatory factor release (TNF-α, IL-6), transforming M2 macrophages into the M1 phenotype. Ultimately, the proposed strategy combines PD-L1/PD-1 blockade, imiquimod and mild thermal treatment to synergistically enhance tumor immunogenicity, remodel the TME, and restrain hepatic carcinoma, making strides in ICB synergistic immune-thermal therapy.


Assuntos
Ouro , Imiquimode , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Terapia Fototérmica , Ouro/química , Animais , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Imiquimode/química , Imiquimode/uso terapêutico , Inibidores de Checkpoint Imunológico/química , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Humanos , Imunoterapia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Linhagem Celular Tumoral
15.
Nat Commun ; 15(1): 6655, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107376

RESUMO

Polymeric-based dielectric materials hold great potential as energy storage media in electrostatic capacitors. However, the inferior thermal resistance of polymers leads to severely degraded dielectric energy storage capabilities at elevated temperatures, limiting their applications in harsh environments. Here we present a flexible laminated polymer nanocomposite where the polymer component is confined at the nanoscale, achieving improved thermal-mechanical-electrical stability within the resulting nanocomposite. The nanolaminate, consisting of nanoconfined polyetherimide (PEI) polymer sandwiched between solid Al2O3 layers, exhibits a high energy density of 18.9 J/cm3 with a high energy efficiency of ~ 91% at elevated temperature of 200°C. Our work demonstrates that nanoconfinement of PEI polymer results in reduced diffusion coefficient and constrained thermal dynamics, leading to a remarkable increase of 37°C in glass-transition temperature compared to bulk PEI polymer. The combined effects of nanoconfinement and interfacial trapping within the nanolaminates synergistically contribute to improved electrical breakdown strength and enhanced energy storage performance across temperature range up to 250°C. By utilizing the flexible ultrathin nanolaminate on curved surfaces such as thin metal wires, we introduce an innovative concept that enables the creation of a highly efficient and compact metal-wired capacitor, achieving substantial capacitance despite the minimal device volume.

16.
Nanomicro Lett ; 16(1): 240, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980475

RESUMO

Single-atom materials have demonstrated attractive physicochemical characteristics. However, understanding the relationships between the coordination environment of single atoms and their properties at the atomic level remains a considerable challenge. Herein, a facile water-assisted carbonization approach is developed to fabricate well-defined asymmetrically coordinated Co-N4-O sites on biomass-derived carbon nanofiber (Co-N4-O/NCF) for electromagnetic wave (EMW) absorption. In such nanofiber, one atomically dispersed Co site is coordinated with four N atoms in the graphene basal plane and one oxygen atom in the axial direction. In-depth experimental and theoretical studies reveal that the axial Co-O coordination breaks the charge distribution symmetry in the planar porphyrin-like Co-N4 structure, leading to significantly enhanced dielectric polarization loss relevant to the planar Co-N4 sites. Importantly, the film based on Co-N4-O/NCF exhibits light weight, flexibility, excellent mechanical properties, great thermal insulating feature, and excellent EMW absorption with a reflection loss of - 45.82 dB along with an effective absorption bandwidth of 4.8 GHz. The findings of this work offer insight into the relationships between the single-atom coordination environment and the dielectric performance, and the proposed strategy can be extended toward the engineering of asymmetrically coordinated single atoms for various applications.

17.
Light Sci Appl ; 13(1): 159, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982066

RESUMO

Ultrasound sensors play an important role in biomedical imaging, industrial nondestructive inspection, etc. Traditional ultrasound sensors that use piezoelectric transducers face limitations in sensitivity and spatial resolution when miniaturized, with typical sizes at the millimeter to centimeter scale. To overcome these challenges, optical ultrasound sensors have emerged as a promising alternative, offering both high sensitivity and spatial resolution. In particular, ultrasound sensors utilizing high-quality factor (Q) optical microcavities have achieved unprecedented performance in terms of sensitivity and bandwidth, while also enabling mass production on silicon chips. In this review, we focus on recent advances in ultrasound sensing applications using three types of optical microcavities: Fabry-Perot cavities, π-phase-shifted Bragg gratings, and whispering gallery mode microcavities. We provide an overview of the ultrasound sensing mechanisms employed by these microcavities and discuss the key parameters for optimizing ultrasound sensors. Furthermore, we survey recent advances in ultrasound sensing using these microcavity-based approaches, highlighting their applications in diverse detection scenarios, such as photoacoustic imaging, ranging, and particle detection. The goal of this review is to provide a comprehensive understanding of the latest advances in ultrasound sensing with optical microcavities and their potential for future development in high-performance ultrasound imaging and sensing technologies.

18.
PLoS One ; 19(7): e0306272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39028710

RESUMO

Abnormal speech prosody has been widely reported in individuals with autism. Many studies on children and adults with autism spectrum disorder speaking a non-tonal language showed deficits in using prosodic cues to mark focus. However, focus marking by autistic children speaking a tonal language is rarely examined. Cantonese-speaking children may face additional difficulties because tonal languages require them to use prosodic cues to achieve multiple functions simultaneously such as lexical contrasting and focus marking. This study bridges this research gap by acoustically evaluating the use of Cantonese speech prosody to mark information structure by Cantonese-speaking children with and without autism spectrum disorder. We designed speech production tasks to elicit natural broad and narrow focus production among these children in sentences with different tone combinations. Acoustic correlates of prosodic focus marking like f0, duration and intensity of each syllable were analyzed to examine the effect of participant group, focus condition and lexical tones. Our results showed differences in focus marking patterns between Cantonese-speaking children with and without autism spectrum disorder. The autistic children not only showed insufficient on-focus expansion in terms of f0 range and duration when marking focus, but also produced less distinctive tone shapes in general. There was no evidence that the prosodic complexity (i.e. sentences with single tones or combinations of tones) significantly affected focus marking in these autistic children and their typically-developing (TD) peers.


Assuntos
Transtorno do Espectro Autista , Idioma , Humanos , Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/psicologia , Masculino , Feminino , Criança , Acústica da Fala , Pré-Escolar , Fala/fisiologia
19.
Materials (Basel) ; 17(14)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39063734

RESUMO

Improving ferro-piezoelectric properties of niobate-based perovskites is highly desirable for developing eco-friendly high-performance sensors and actuators. Although electro-strain coupling is usually obtained by constructing multiphase boundaries via complex chemical compositions, defect engineering can also create opportunities for novel property and functionality advancements. In this work, a representative tetragonal niobate-based perovskite, i.e., KNbO3, is studied by using first-principles calculations. Two intrinsic types of Nb antisite defect complexes are selected to mimic alkali-deficiency induced excess Nb antisites in experiments. The formation energy, electronic profiles, polarization, and piezoelectric constants are systematically analyzed. It is shown that the structural distortion and chemical heterogeneity around the energetically favorable antisite pair defects, i.e., (NbK4·+KNb4'), lower the crystal symmetry of KNbO3 from tetragonal to triclinic phase, and facilitate polarization emergence and reorientation to substantially enhance intrinsic ferro-piezoelectricity (i.e., spontaneous polarization Ps of 68.2 µC/cm2 and piezoelectric strain constant d33 of 228.3 pC/N) without complicated doping and alloying.

20.
Org Lett ; 26(29): 6290-6294, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39023054

RESUMO

Strategies that fully convert available racemic substrates into valuable enantioenriched products are urgently needed in organic synthesis. Reported herein is the first parallel kinetic asymmetric transformation of racemic cyclohexadienones. Racemic cyclohexadienones are first diastereoselectively converted into a new pair of racemic transient dienol intermediates, which are then parallel protonated by chiral phosphoric acid to deliver two sets of hydroindole products bearing a quaternary stereocenter with generally excellent enantioselectivity.

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