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1.
Tob Control ; 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39419609

RESUMEN

BACKGROUND: In April 2020, Japan's revised Health Promotion Act (HPA) banned cigarette smoking and heated tobacco products (HTP) use in indoor public places but exempted small establishments and permitted smoking-designated/HTP-designated rooms. This pre-post study evaluated the effectiveness of the HPA. METHODS: Data were from waves 1 to 4 (2018-2021) of the International Tobacco Control Japan Surveys among a national cohort of adults who smoke cigarettes, use HTPs and do not use any tobacco products. The sample sizes in the respective surveys were 4615, 4222, 4387 and 4254. Multivariable logistic regression models employing generalised estimating equations estimated the prevalence of observed and self-reported indoor smoking/HTP use in key public venues (restaurants/cafés, bars/pubs and workplaces), smoke-free places, and homes, and smoke-free/HTP aerosol-free home policies (model 1). The models were additionally adjusted for waves 1-4 to estimate the impacts of the HPA (model 2). RESULTS: The implementation of the HPA significantly reduced observed indoor smoking in bars/pubs (model 1: 82.2% (pre) to 55.5% (post), model 2: p=0.04) but not in restaurants/cafés (model 1: 53.0%-24.9%, model 2: p=0.15) or workplaces (model 1: 35.3%-30.1%, model 2: p=0.62). Observed indoor HTP use was also common postimplementation (restaurants/cafés: 19.6%, bars/pubs: 53.9%, workplaces: 36.4%). The implementation of the HPA was associated with a significant increase in observed HTP use in smoke-free places (model 1: 26.3%-33.3%, model 2: p=0.001) and a suggestive increase in homes without HTP aerosol-free policies among adults who smoke (model 1: 64.0%-77.0%, model 2: p=0.09). CONCLUSIONS: The implementation of the HPA was limited in its effectiveness. Comprehensive regulations with no exemptions are needed in Japan.

2.
Small ; : e2405759, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39221523

RESUMEN

The stability of supported nano-metal catalysts holds significant importance in both scientific and economic practice, beyond the long pursuit of enhanced activity. While previous efforts have concentrated on augmenting the interaction between nano-metals and carriers, in the thermodynamic macro-perspective, to achieve optimized repression upon particle migration coalescence and Ostwald ripening, nevertheless, the microscale kinetics of migrating catalyst particles driven by the reaction remains unknown. In this work, the migration of nano-copper particles is investigated during hydrogen oxidation reaction by utilizing high spatiotemporal resolution of environmental transmission electron microscopy. It is shown that there exists a delicate correlation between the migration dynamics of nano-copper particles and the evolution of asymmetrically distributed Cu and Cu2O phases over the particle surface. It is found that the interplay of reduction and oxidation near the surface areas filled with Cu and Cu2O phases can facilitate the pressure gradient, which drives the migration of nano-particles. A driving force model is therefore established which is capable of qualitatively explaining the influences of reaction conditions such as temperature and hydrogen-to-oxygen ratio on the reaction-driven particle migration. This work adds a potential yet critical perspective to understanding particle migration and thus the nano-metal catalyst particle sintering in heterogeneous catalysis.

3.
J Clin Pathol ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160061

RESUMEN

AIMS: Phyllodes tumours (PTs) are relatively common fibroepithelial tumours comprising epithelial and stromal component. Usually, PTs show a spindle cell morphology with a fibroblast phenotype, while some tumour cells exhibit epithelioid morphological features and sarcomatoid transformation. However, the molecular characteristics of this morphology subset remain unclear. This study aimed to summarise the clinicopathological, morphological and molecular characteristics of seven cases of PT with epithelioid features. METHODS: Morphological and clinicopathological characteristics were observed and retrieved. Immunohistochemistry, immunofluorescence and electron microscope were performed on seven cases of epithelioid PT to explore immunophenotypic and ultrastructural characteristics. Transcriptomic and proteomic analyses were conducted to compare differentially expressed genes and proteins between epithelioid PT and classical PT. RESULTS: Patients with epithelioid PT exhibit a high recurrence rate (42.8%). Morphologically, in addition to having epithelioid cytological features, neoplastic stromal cells exhibit moderate to marked atypia and often exhibit sarcomatoid transformation, similar to the characteristics of borderline PT. Transcriptomic and proteomic analyses demonstrated that epithelioid PTs are distinct from classical PTs in gene expression and protein abundance levels. Immunohistochemical analysis showed that among all differentially expressed proteins, epithelioid PT showed abnormal p16/retinoblastoma expression patterns, similar to those of malignant PT. CONCLUSIONS: Epithelioid PT has unique morphological characteristics, biological behaviour and protein expression profile, which meets the diagnostic criteria of borderline PT and is prone to sarcomatoid transformation. It may be a special morphological subgroup of borderline PT and has partial characteristics of malignant PT, which should be taken seriously in pathological diagnosis and clinical management.

4.
Phys Rev Lett ; 133(3): 036203, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39094165

RESUMEN

Accurate description of nonadiabatic dynamics of molecules at metal surfaces involving electron transfer has been a long-standing challenge for theory. Here, we tackle this problem by first constructing high-dimensional neural network diabatic potentials including state crossings determined by constrained density functional theory, then applying mixed quantum-classical surface hopping simulations to evolve coupled electron-nuclear motion. Our approach accurately describes the nonadiabatic effects in CO scattering from Au(111) without empirical parameters and yields results agreeing well with experiments under various conditions for this benchmark system. We find that both adiabatic and nonadiabatic energy loss channels have important contributions to the vibrational relaxation of highly vibrationally excited CO(v_{i}=17), whereas relaxation of low vibrationally excited states of CO(v_{i}=2) is weak and dominated by nonadiabatic energy loss. The presented approach paves the way for accurate first-principles simulations of electron transfer mediated nonadiabatic dynamics at metal surfaces.

5.
Tob Control ; 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879182

RESUMEN

INTRODUCTION: Dual use of e-cigarettes and cigarettes is a growing usage pattern in adults, but little is known about the motivations underlying this trend. We investigated the reasons for e-cigarette use among adults who smoke, considering variation in sociodemographic subgroups. METHODS: This repeated cross-sectional study analysed adults who smoked at least weekly and vaped at any frequency. Data were from the International Tobacco Control Korea Surveys conducted in 2016 (n=164) and 2020 (n=1088). Fourteen reasons for e-cigarette use were assessed in both waves. Subgroup analyses were performed by age, sex and educational level. RESULTS: The top reasons for e-cigarette use in 2020 were curiosity (62.8%), less harmful than smoking (45.4%) and taste (43.2%). Curiosity was the most cited across age, sex and education subgroups. Significant differences were observed in 2020 compared with 2016, with lower percentages in goal-oriented reasons: helping quit smoking (36.3% vs 48.9%; p=0.017), helping cut down smoking (35.3% vs 52.7%; p=0.001), less harmful to others (39.0% vs 54.6%; p=0.003) and more acceptable (31.6% vs 61.2%; p<0.001). By contrast, non-goal-oriented reasons showed higher percentages in 2020, such as curiosity (62.8% vs 27.9%; p<0.001), taste (43.2% vs 22.1%; p<0.001) and enjoyment (26.8% vs 8.6%; p<0.001). In 2020, a majority of adults who smoked and vaped (53.3%) reported no intention to quit or reduce smoking. CONCLUSIONS: E-cigarette use for curiosity and pleasure predominated among adults who smoked. The reasons for dual use in adults have shifted from goal-oriented to non-goal-oriented.

6.
J Pharm Anal ; 14(4): 100905, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38665224

RESUMEN

Epigenomic imbalance drives abnormal transcriptional processes, promoting the onset and progression of cancer. Although defective gene regulation generally affects carcinogenesis and tumor suppression networks, tumor immunogenicity and immune cells involved in antitumor responses may also be affected by epigenomic changes, which may have significant implications for the development and application of epigenetic therapy, cancer immunotherapy, and their combinations. Herein, we focus on the impact of epigenetic regulation on tumor immune cell function and the role of key abnormal epigenetic processes, DNA methylation, histone post-translational modification, and chromatin structure in tumor immunogenicity, and introduce these epigenetic research methods. We emphasize the value of small-molecule inhibitors of epigenetic modulators in enhancing antitumor immune responses and discuss the challenges of developing treatment plans that combine epigenetic therapy and immunotherapy through the complex interaction between cancer epigenetics and cancer immunology.

7.
Cell Mol Immunol ; 21(6): 604-619, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38689020

RESUMEN

Autoreactive CD8+ T cells play a key role in type 1 diabetes (T1D), but the antigen spectrum that activates autoreactive CD8+ T cells remains unclear. Endoplasmic reticulum stress (ERS) has been implicated in ß-cell autoantigen generation. Here, we analyzed the major histocompatibility complex class I (MHC-I)-associated immunopeptidome (MIP) of islet ß-cells under steady and ERS conditions and found that ERS reshaped the MIP of ß-cells and promoted the MHC-I presentation of a panel of conventional self-peptides. Among them, OTUB258-66 showed immunodominance, and the corresponding autoreactive CD8+ T cells were diabetogenic in nonobese diabetic (NOD) mice. High glucose intake upregulated pancreatic OTUB2 expression and amplified the OTUB258-66-specific CD8+ T-cell response in NOD mice. Repeated OTUB258-66 administration significantly reduced the incidence of T1D in NOD mice. Interestingly, peripheral blood mononuclear cells (PBMCs) from patients with T1D, but not from healthy controls, showed a positive IFN-γ response to human OTUB2 peptides. This study provides not only a new explanation for the role of ERS in promoting ß-cell-targeted autoimmunity but also a potential target for the prevention and treatment of T1D. The data are available via ProteomeXchange with the identifier PXD041227.


Asunto(s)
Linfocitos T CD8-positivos , Diabetes Mellitus Tipo 1 , Estrés del Retículo Endoplásmico , Células Secretoras de Insulina , Ratones Endogámicos NOD , Animales , Diabetes Mellitus Tipo 1/inmunología , Humanos , Linfocitos T CD8-positivos/inmunología , Estrés del Retículo Endoplásmico/inmunología , Ratones , Células Secretoras de Insulina/inmunología , Células Secretoras de Insulina/metabolismo , Femenino , Autoantígenos/inmunología , Péptidos/inmunología , Péptidos/farmacología , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo
8.
ACS Sens ; 9(3): 1410-1418, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38456391

RESUMEN

Dimethyl disulfide (DMDS) is a common odor pollutant with an extremely low olfactory threshold. Highly sensitive and selective detection of DMDS in ambient humid air background, by metal oxide semiconductor (MOS) sensors, is highly desirable to address the increased public concern for health risk. However, it has still been a critical challenge up to now. Herein, p-type delafossite CuGaO2 has been proposed as a promising DMDS sensing material owing to its striking hydrophobicity (revealed by water contact angle measurement) and excellent partial catalytic oxidation properties (indicated by mass spectroscopy). The present CuGaO2 sensor shows a selective DMDS response, with satisfied humidity resistance performance and long-term stability at a relatively low operation temperature of 140 °C. An ultrahigh response of 100 to 10 ppm DMDS and a low limit of detection of 3.3 ppb could be achieved via a pulsed temperature modulation strategy. A smart sensing system based on a CuGaO2 sensor has been developed, which could precisely monitor DMDS vapor in ambient humid air, even with the presence of multiple interfering gases, demonstrating the practical application capability of MOS sensors for environmental odor monitoring.


Asunto(s)
Disulfuros , Gases , Óxidos/química , Temperatura
9.
iScience ; 27(1): 108723, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38283328

RESUMEN

The NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome has been involved in the pathogenesis of various chronic liver diseases. However, its role in hepatitis B virus (HBV)-associated hepatitis remains unknown. Here we demonstrate the synergistic effect of HBV with potential intrahepatic danger signals on NLRP3 inflammasome activation. HBV exposure at the appropriate temporal points enhances potassium efflux-dependent NLRP3 inflammasome activation in macrophages and also increases NLRP3 inflammasome-mediated inflammation in HBV-transgenic mouse model. HBV-mediated synergism with intrahepatic signals represented by ATP molecules on NLRP3 activation was observed via relevance analysis, confocal microscopy, and co-immunoprecipitation, and its effector cytokines exhibit positive associations with hepatic inflammation in patients with severe hepatitis B. Furthermore, the synergism of HBV on NLRP3 inflammasome activation owes to increased sodium influx into macrophages. Our data demonstrate that HBV contributes to hepatic inflammation via sodium influx-dependent synergistic activation of NLRP3 inflammasome, which provides a deeper understanding of immune pathogenesis in HBV-associated hepatitis.

10.
Tob Control ; 33(e1): e128-e131, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-36609491

RESUMEN

OBJECTIVE: To examine the impact of menthol cigarette bans on use and purchasing of illicit cigarettes among menthol and non-menthol smokers in seven Canadian provinces. METHODS: Data from 1098 non-menthol smokers and 138 menthol smokers in Canada who completed the ITC Four Country Smoking and Vaping Survey in 2016 (pre-ban) and 2018 (post-ban). Brand validation analysis was conducted to (1) compare self-reported use of menthols versus actual use of menthols as regular brand, and verify self-reported purchasing of menthols among pre-ban menthol smokers at post-ban; and (2) assess pre-post ban changes in purchasing of illicit cigarettes from First Nations reserves among non-menthol smokers and menthol smokers. RESULTS: Among the subset of 138 pre-ban menthol smokers, 36 (19.5%) reported smoking menthols at post-ban. Brand validation analyses showed that 19 (9.0%) were actually using a non-menthol brand; of the 17 (10.5%) who were actually using a menthol brand, 13 (7.9%) bought a menthol brand at last purchase, and 4 (2.6%) bought a non-menthol brand. Among the full sample of smokers who purchased cigarettes from First Nations reserves at both pre-ban and post-ban, there was no change in purchasing of menthols (n=9 menthol smokers; 51.2% vs 51.2%, p=1.00), non-menthols (n=1024 non-menthol smokers; 9.1% vs 8.7%, p=0.69) or all cigarettes (menthol+non-menthol) (n=1086 smokers; 9.7% vs 9.2%, p=0.56). CONCLUSIONS: Actual rates of brand-verified menthol smoking were substantially lower than self-reported rates at post-ban. After Canada's menthol ban, there was no increase in illicit purchasing of menthol or non-menthol cigarettes from First Nations reserves.


Asunto(s)
Productos de Tabaco , Vapeo , Humanos , Mentol , Canadá/epidemiología , Fumar/epidemiología
11.
J Neurosci Methods ; 401: 110007, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37952831

RESUMEN

BACKGROUND: Blood perfusion of the optic nerve (ON) plays a key role in many optic neuropathies. Microvascular changes precede or accompany neuronal changes, and detecting these changes at an early stage may facilitate early treatment to avoid blindness. However, the quantification of ON blood perfusion remains a challenge. This study aimed to evaluate the viability of three-dimensional pseudocontinuous arterial spin labelling (3D-pCASL) MRI for the quantification of ON blood flow (BF). NEW METHOD: The ON segmentation was performed using nnFormer on a cohort of ten participants (4 males, 6 females, 25-59 years old). Subsequently, the mean BF of each ON segment was calculated using whole brain 3D-pCASL image data. RESULTS: The average ON-BF values of the left and right intraorbital segments, left and right intracanalicular segments, left and right intracranial segments, optic chiasma, and left and right optic tract were 41.308 mL/100 g/min, 43.281 mL/100 g/min, 53.188 mL/100 g/min, 57.202 mL/100 g/min, 45.089 mL/100 g/min, 49.554 mL/100 g/min, 42. 326 mL/100 g/min, 43.831 mL/100 g/min and 45.176 mL/100 g/min, respectively. The ON-BF correlated with cerebral BF (r = 0.503, p = 0.024). COMPARISON WITH EXISTING METHOD(S): The 3D-pCASL can measure tissue microvascular blood perfusion in absolute quantitative units with good test-retest repeatability over a wide field of view and without restrictions on depth. The use of the nnFormer makes the measurement easy, objective and reproducible. CONCLUSIONS: The study showed that, 3D-pCASL may be a promising tool for detecting abnormal ON-BF. In particular, 3D-pCASL coupled with the nnFormer provides an objective, reproducible, and reliable method to quantify BF in ON.


Asunto(s)
Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Angiografía por Resonancia Magnética/métodos , Marcadores de Spin , Circulación Cerebrovascular/fisiología , Nervio Óptico
12.
ACS Sens ; 9(1): 206-216, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38114442

RESUMEN

Though considerable progress has been achieved on gas molecule recognition by electronic nose (e-nose) comprised of nonselective (metal oxide) semiconductor chemiresistors, extracting adequate molecular features within short time (<1 s) remains a big obstacle, which hinders the emerging e-nose applications in lethal or explosive gas warning. Herein, by virtue of the ultrafast (∼20 µs) thermal relaxation time of self-heated WO3-based chemiresistors fabricated via oblique angle deposition, instead of external heating, self-heating temperature modulation has been proposed to generate sufficient electrical response features. Accurate discrimination of 12 gases (including 3 xylene isomers with the same function group and molecular weight) has been readily achieved within 0.5-1 s, which is one order faster than the state-of-the-art e-noses. A smart wireless e-nose, capable of instantaneously discriminating target gas in ambient air background, has been developed, paving the way for the practical applications of e-nose in the area of homeland security and public health.


Asunto(s)
Gases , Calefacción , Temperatura , Electrónica , Óxidos
13.
Tob Induc Dis ; 21: 121, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37781238

RESUMEN

INTRODUCTION: Heated tobacco products (HTPs) and nicotine vaping products (NVPs) both are legal consumer products in the Republic of Korea. Little is known about perceptions of harmfulness of HTPs and NVPs relative to cigarettes in South Korea among adults who smoke, and how exposure to marketing may be associated with harmfulness perceptions. METHODS: This study used data from the 2020 International Tobacco Control (ITC) Korea Survey, and included 3713 adult (aged 19 years) cigarette smokers who were: 1) exclusive smokers (n=1845); 2) dual HTP + cigarette consumers (n=1130); 3) dual NVP + cigarette consumers (n=224); and 4) triple consumers (all three products, n=514). Weighted multinomial regression models were conducted to estimate smokers' perceptions of harmfulness of HTPs and NVPs compared to cigarettes, NVPs to HTPs, and self-reported exposure to HTP/NVP advertising. Analyses compared the perceptions of harmfulness between the four different consumer groups, and tested whether exposure to HTP/NVP advertising was associated with perceptions of lower relative harm. RESULTS: Among all respondents, 27.5% believe that HTPs are less harmful than cigarettes and 23.4% believe that NVPs are less harmful than cigarettes. Exclusive cigarettes smokers were significantly less likely to perceive that HTPs and NVPs are less harmful than cigarettes compared to dual HTP + cigarette consumers, dual NVP + cigarette consumers, and triple consumers (all p<0.001). Half of respondents perceive NVPs as equally harmful as HTPs (14.1% perceive NVPs as more harmful than HTPs). Exposure to HTP/NVP advertising was associated with perceiving these products as less harmful than cigarettes. CONCLUSIONS: About one-quarter of Korean cigarette smokers perceive HTPs and NVPs as less harmful than cigarettes. Further investigation is required to understand how harm perceptions and HTP/NVP advertising are related to changes in product use, such as switching between products, using multiple products, or discontinuing all product use.

14.
Heliyon ; 9(7): e17933, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37539166

RESUMEN

[This retracts the article DOI: 10.1016/j.heliyon.2022.e12456.].

15.
Bioresour Technol ; 384: 129278, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37290707

RESUMEN

In this study, α-L-arabinofuranosidase (AF) from Aspergillus awamori was heterologously expressed in Pichia pastoris X33, with a 1-fold increase in AF activity after codon and vector optimization. AF remained stable at 60-65 °C and displayed a broad pH stability range of 2.5-8.0. It also demonstrated considerable resistance to pepsin and trypsin. Furthermore, compared with xylanase alone, AF with xylanase exhibited a marked synergistic effect in the degradation of expanded corn bran, corn bran, and corn distillers' dried grains with solubles, reducing sugars by 3.6-fold, 1.4-fold, and 6.5-fold, respectively, with the degree of synergy increasing to 4.61, 2.44, and 5.4, respectively, while in vitro dry matter digestibility values were 17.6%, 5.2%, and 8.8%, respectively. After enzymatic saccharification, corn byproducts were converted to prebiotic xylo-oligosaccharides and arabinoses, thereby demonstrating the favorable properties of AF in the degradation of corn biomass and its byproducts.


Asunto(s)
Glicósido Hidrolasas , Zea mays , Zea mays/metabolismo , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Aspergillus/genética , Aspergillus/metabolismo
17.
Tob Induc Dis ; 21: 84, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37360042

RESUMEN

INTRODUCTION: In March 2020, the US Food and Drug Administration (FDA) finalized new pictorial health warnings (PHWs), covering 50% of the front and back of the pack; however, legal challenges from cigarette manufacturers have prevented the new warnings from being implemented. About 70% of adults in the general US population support PHWs. This study assessed support for PHWs in 2016, 2018 and 2020 among US adults (aged ≥18 years) who currently smoke or formerly smoked cigarettes. We also assessed factors related to support. METHODS: Respondents included adults who currently or formerly smoked cigarettes and participated in at least one wave of the US ITC Smoking and Vaping Surveys: Wave 1 (2016, n=2557); Wave 2 (2018, n=2685); and Wave 3 (2020, n=1112). We assessed changes in support for PHWs between 2016 and 2020, and assessed factors related to support (support vs oppose/don't know). Analyses were conducted on weighted data. RESULTS: Overall, 38.0% of respondents supported PHWs in 2016, with a significant increase to 44.7% in 2018 (p<0.001), and leveling off to 45.0% in 2020 (2018 vs 2020, p=0.91). Support was highest among former smokers and lowest among daily smokers in all three survey years. Support for PHWs at all survey years was significantly higher among those who formerly smoked, were younger (aged 18-39 vs ≥40 years), those who identified as Black (vs White), and planned to quit smoking (vs not planning to quit). There were no differences by income level, education level, or sex. CONCLUSIONS: Nearly half of US adults who smoke cigarettes or quit smoking supported PHWs in 2020, with support being higher among younger adults, ethnic minorities, and those who formerly smoked. Support increased between 2016 and 2018, but not between 2018 and 2020. Similar to other studies, fewer current and former smokers supported PHWs compared to the US adult general population.

18.
Artículo en Inglés | MEDLINE | ID: mdl-37247316

RESUMEN

As powerful tools deep neural networks have been successfully adopted for nuclei detection in histopathology images, whereas require the same probability distribution between training and testing data. However, domain shift among histopathology images widely exists in real-world applications and severely deteriorates the detection performance of deep neural networks. Despite encouraging results of existing domain adaptation methods, there remain challenges for cross-domain nuclei detection task. First, in view of the tiny size of nuclei, it is actually very difficult to obtain sufficient nuclei features, thus leading to a negative influence for feature alignment. Second, due to unavailable annotations in target domain, some extracted features contain background pixels and are thereby indiscriminative, which can largely confuse the alignment procedure. To address these challenges, in this paper, we propose an end-to-end graph-based nuclei feature alignment (GNFA) method for boosting cross-domain nuclei detection. Concretely, sufficient nuclei features are generated from nuclei graph convolutional network (NGCN) by aggregating information of adjacent nuclei upon construction of nuclei graph for successful alignment. In addition, importance learning module (ILM) is designed to further select discriminative nuclei features for mitigating negative influence of background pixels in target domain during alignment. By utilizing sufficient and discriminative node features generated from GNFA, our method can successfully perform feature alignment and effectively alleviate domain shift problem for nuclei detection. Extensive experiments of multiple adaptation scenarios reveal that our method achieves state-of-the-art performance in cross-domain nuclei detection compared with existing domain adaptation methods.

19.
ACS Appl Mater Interfaces ; 15(21): 25726-25733, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37199606

RESUMEN

UV photoactivation has been widely employed to trigger the response of semiconductor chemiresistors at room temperature (RT). Generally, continuous UV (CU) irradiation is applied, and an apparent maximal response could be obtained via optimizing UV intensity. However, owing to the conflicting roles of (UV) photoactivation in the gas response process, we do not think the potential of photoactivation has been fully explored. Herein, a pulsed UV light modulation (PULM) photoactivation protocol has been proposed. Pulsed UV-on facilitates the generation of surface reactive oxygen species and refreshes the surface of chemiresistors, while pulsed UV-off avoids the side effects of UV-induced desorption of the target gas and the decline of base resistance. PULM enables decoupling those conflicting roles of CU photoactivation, resulting in a drastic boost of response to trace (20 ppb) NO2 from 1.9 (CU) to 131.1 (PULM UV-off), and a decline of limit of detection from 2.6 ppb (CU) to 0.8 ppb (PULM) for a ZnO chemiresistor. This work highlights that PULM allows full exploitation of the potential of nanomaterials for sensitively detecting trace (ppb-level) toxic gas molecules and opens a new opportunity for designing highly sensitive, low-power consumed RT chemiresistors for ambient air quality monitoring.

20.
iScience ; 26(4): 106387, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37034984

RESUMEN

Chemiresistive gas sensors generally surfer from low selectivity, inferior anti-humidity, low response signal or signal-to-noise ratio, severely limiting the precise detection of chemical agents. Herein, we exploit high-performance gas sensors based on topological insulator Bi2Se3 that is distinguished from conventional materials by robust metallic surface states protected by time-reversal symmetry. In the presence of Se vacancies, Bi2Se3 nanosheets exhibit excellent gas sensing capability toward NO2, with a high response of 93% for 50 ppm and an ultralow theoretical limit of detection concentration about 0.06 ppb at room temperature. Remarkably, Bi2Se3 demonstrates ultrahigh anti-humidity interference characteristics, as the response with standard deviation of only 3.63% can be achieved in relative humidity range of 0-80%. These findings are supported by first-principles calculations, with analyses on adsorption energy and charge transfer directly revealing the anti-humidity and selectivity. This work may pave the way for implementation of exotic quantum states for intelligent applications.

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