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1.
Br J Hosp Med (Lond) ; 85(6): 1-10, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38941977

RESUMO

Aims/Background Trait emotional intelligence is associated with anxiety and depression symptoms and quality of life in cancer patients. However, studies on the relationship of trait emotional intelligence with anxiety, depression, and quality of life in gastric cancer patients are limited. This study investigates the relationship of trait emotional intelligence with depression and quality of life in gastric cancer patients to provide a theoretical basis for clinical management. Methods A total of 270 patients with gastric cancer treated in our hospital from July 2020 to July 2023 were selected, of which 31 patients with missing questionnaire entries and missed visits were screened out, resulting in the enrolment of 239 gastric cancer patients in this study. In this survey, self-administered general information questionnaires, namely Trait Emotional Intelligence Short Form (TEIQue-SF), European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), and Hospital Anxiety and Depression Scale (HADS) were used. Results TEIQue-SF total scores were positively correlated with QLQ-C30 scores (p < 0.001) and negatively correlated with HADS-A and HADS-D scores (p < 0.001). TEIQue-SF total score was a superior positive predictor of the QLQ-C30 score (ß = 0.412, p < 0.001) and a superior negative predictor of the HADS score (ß = -0.740, p < 0.001). TEIQue-SF total score (ß = 0.141, p = 0.006) and HADS score (ß = -0.665, p < 0.001) were good predictors of QLQ-C30 score. The direct effect of TEIQue-SF total score on QLQ-C30 score was 0.141, while HADS score between TEIQue-SF total score and QLQ-C30 score had a mediated effect value of 0.492. Conclusion Trait emotional intelligence not only directly affects the quality of life, but also indirectly affects the quality of life through anxiety and depression. Clinicians should pay attention to the anxiety, depression, and emotional intelligence of patients with gastric cancer to help them improve their quality of life.


Assuntos
Ansiedade , Depressão , Inteligência Emocional , Qualidade de Vida , Neoplasias Gástricas , Humanos , Qualidade de Vida/psicologia , Neoplasias Gástricas/psicologia , Masculino , Feminino , Pessoa de Meia-Idade , Ansiedade/psicologia , Depressão/psicologia , Depressão/epidemiologia , Idoso , Inquéritos e Questionários , Adulto
2.
Toxics ; 12(5)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38787110

RESUMO

Solar radiation triggers atmospheric nitrous acid (HONO) photolysis, producing OH radicals, thereby accelerating photochemical reactions, leading to severe secondary pollution formation. Missing daytime sources were detected in the extensive HONO budget studies carried out in the past. In the rural North China Plain, some studies attributed those to soil emissions and more recent studies to dew evaporation. To investigate the contributions of these two processes to HONO temporal variations and unknown production rates in rural areas, HONO and related field observations obtained at the Gucheng Agricultural and Ecological Meteorological Station during spring and autumn were thoroughly analyzed. Morning peaks in HONO frequently occurred simultaneously with those of ammonia (NH3) and water vapor both during spring and autumn, which were mostly caused by dew and guttation water evaporation. In spring, the unknown HONO production rate revealed pronounced afternoon peaks exceeding those in the morning. In autumn, however, the afternoon peak was barely detectable compared to the morning peak. The unknown afternoon HONO production rates were attributed to soil emissions due to their good relationship to soil temperatures, while NH3 soil emissions were not as distinctive as dew emissions. Overall, the relative daytime contribution of dew emissions was higher during autumn, while soil emissions dominated during spring. Nevertheless, dew emission remained the most dominant contributor to morning time HONO emissions in both seasons, thus being responsible for the initiation of daytime OH radical formation and activation of photochemical reactions, while soil emissions further maintained HONO and associated OH radial formation rates at a high level, especially during spring. Future studies need to thoroughly investigate the influencing factors of dew and soil emissions and establish their relationship to HONO emission rates, form reasonable parameterizations for regional and global models, and improve current underestimations in modeled atmospheric oxidation capacity.

3.
Sci Prog ; 107(1): 368504241227620, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361488

RESUMO

This article investigates data-driven distributed bipartite formation issues for discrete-time multi-agent systems with communication constraints. We propose a quantized data-driven distributed bipartite formation control approach based on the plant's quantized and saturated information. Moreover, compared with existing results, we consider both the fixed and switching topologies of multi-agent systems with the cooperative-competitive interactions. We establish a time-varying linear data model for each agent by utilizing the dynamic linearization method. Then, using the incomplete input and output data of each agent and its neighbors, we construct the proposed quantized data-driven distributed bipartite formation control scheme without employing any dynamics information of multi-agent systems. We strictly prove the convergence of the proposed algorithm, where the proposed approach can ensure that the bipartite formation tracking errors converge to the origin, even though the communication topology of multi-agent systems is time-varying switching. Finally, simulation and hardware tests demonstrate the effectiveness of the proposed scheme.

4.
Sci Total Environ ; 913: 169309, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38103604

RESUMO

The unknown daytime source of HONO has been extensively investigated due to unexplained atmospheric oxidation capacity and current modelling bias, especially during cold seasons. In this study, abrupt morning increases in atmospheric HONO at a rural site in the North China Plain (NCP) were observed almost on daily basis, which were closely linked to simultaneous rises in atmospheric water vapor content and NH3 concentrations. Dew and guttation water formation was frequently observed on wheat leaves, from which water samples were taken and chemically analyzed for the first time. Results confirmed that such natural processes likely governed the daily nighttime deposition and daytime release of HONO and NH3, which have not been considered in the numerous HONO budget studies investigating its large missing daytime source in the NCP. The dissolved HONO and NH3 in leaf surface water droplets reached 1.4 and 23 mg L-1 during the morning on average, resulting in averaged atmospheric HONO and NH3 increases of 0.89 ± 0.61 and 43.7 ± 29.3 ppb during morning hours, with relative increases of 186 ± 212 % and 233 ± 252 %, respectively. The high atmospheric oxidation capacity contained within HONO was stored in near surface liquid water (such as dew, guttation and soil surface water) during nighttime, which prevented its atmospheric dispersion after sunset and protected it from photodissociation during early morning hours. HONO was released in a blast during later hours with stronger solar radiation, which triggered and then accelerated daytime photochemistry through the rapid photolysis of HONO and subsequent OH production, especially under high RH conditions, forming severe secondary gaseous and particulate pollution. Results of this study demonstrate that global ecosystems might play significant roles in atmospheric photochemistry through nighttime dew formation and guttation processes.

5.
Oral Maxillofac Surg ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038839

RESUMO

OBJECTIVES: The use of miR-21 expression remains vague in diagnosis of head and neck squamous cell carcinoma (HNSCC). This study aimed to systematically evaluate the diagnostic potential of the miR-21 expression in patients with HNSCCs through investigating and summarizing the results reported in the literature. METHODS: Extant medical databases were examined for articles of clinical study assessing the miR-21 expression in HNSCC cases, published in the past 20 years. Bioinformatics research was also performed for finding miR-21 targets differentially expressed in HNSCC so as to present their biological behaviors. RESULTS: Our meta-analysis comprised 11 studies including 622/450 cases in HNSCC/control group. Forest plots displayed miR-21 which possessed significantly good specificity (0.76, p < 0.001) and sensitivity (0.80, p < 0.001). Diagnostic odds ratio was 2.46 (95% CI 1.87-3.24). Positive and negative likelihood ratio was 3.40 (95% CI 1.94-5.97) and 0.26 (95% CI 0.18-0.38), respectively. Area under the receiver operating characteristic curve was 0.85. CONCLUSION: This study is the highest level of evidence presently available in diagnosing HNSCC. This PRISMA meta-analysis indicated that the pooled results were robust, confirming the oncogenic potential of miR-21 that could be used successfully as a screening biomarker in HNSCC patients. Specifically, the overexpression of miR-21 in these patients presents a worse survival outcome.

6.
Oral Maxillofac Surg ; 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37935817

RESUMO

OBJECTIVE: This narrative review aimed to compile and summarize clinically relevant literature in radiation therapy and to discuss the potential in radioresistant and radiosensitive head and neck squamous cell carcinoma (HNSCC). METHODS AND MATERIALS: Google Scholar, PubMed, and the Cochrane Library were retrieved using combined key words such as "radiotherapy" and "head and neck cancer." Search strings additionally queried were "radioresistant," "radiosensitive," "head and neck region," "squamous cell carcinoma," in combination with Boolean operators 'AND' and 'OR.' Subsequently, the resulting publications were included for review of the full text. RESULTS: Radiotherapeutic responses currently in clinical observation referred to HNSCC scoping were selected into this review. The compiled mechanisms were then detailed concerning on the clinical significance, biological characteristics, and molecular function. CONCLUSIONS: Brachytherapy or/and external-beam radiotherapy are crucial for treating HNSCC especially the early stage patients, but in some patients with locally advanced tumors, their outcome with radiation therapy is poor due to obvious radioresistance. The curative effects mainly depend on the response to radiation therapy so an updated review is needed to optimize further applications in HNSCC radiotherapy.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37729566

RESUMO

This article investigates the online learning and energy-efficient control issues for nonlinear discrete-time multiagent systems (MASs) with unknown dynamics models and antagonistic interactions. First, a distributed combined measurement error function is formulated using the signed graph theory to transfer the bipartite formation issue into a consensus issue. Then, an enhanced linearization controller model for the controlled MASs is developed by employing dynamic linearization technology. After that, an online learning adaptive event-triggered (ET) actor-critic neural network (AC-NN) framework for the MASs to implement bipartite formation control tasks is proposed by employing the optimized NNs and designed adaptive ET mechanism. Moreover, the convergence of the designed formation control framework is strictly proved by the constructed Lyapunov functions. Finally, simulation and experimental studies further demonstrate the effectiveness of the proposed algorithm.

8.
Head Neck ; 45(10): 2515-2524, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37548087

RESUMO

IMPORTANCE: Venous thromboembolism (VTE) is closely relevant to head and neck cancer (HNC) prognosis, but little data exist on the risk prediction of VTE in patients with HNC. OBJECTIVE: To study the risk factors regarding VTE in HNC patients and construct a nomogram model for its prediction. DESIGN, SETTING, AND PARTICIPANTS: A cross-sectional retrospective study was implemented to comparatively analyze 220 HNC patients from January 2018 to December 2021. The Lasso algorithm was used to optimize the selection of variables. A nomogram model for predicting HNC-associated VTE was established using multivariate logistic regression analysis. Internal validation of the model was performed by bootstrap resampling (1000 times). Calibration plot and decision curve analysis (DCA) were applied to evaluate the calibration capability of the prediction model. MAIN OUTCOME AND MEASURE: The demographics, medical history, blood biochemical indicators, and modalities of treatment were included for analysis. RESULTS: The incidence of HNC-associated VTE was 2.8% (55/1967) in authors' affiliation. Five variables of risk factors, including surgery, radiochemotherapy, D-dimer, aspartate transaminase, and globulin, were screened and selected as predictors by Lasso algorithm. A prediction model that incorporated these independent predictors was developed and presented as the nomogram. The model showed good discrimination with a C-index of 0.972 (95% CI: 0.934-0.997), and had an area under the receiver operating characteristic curve value of 0.981 (p < 0.001, 95% CI: 0.964-0.998). The calibration curve displayed good agreement of the predicted probability with the actual observed probability for HNC-associated VTE. The DCA plot showed that the application of this nomogram was associated with net benefit gains in clinical practice. CONCLUSIONS AND RELEVANCE: The high-performance nomogram model developed in this study may help early diagnose the risk of VTE in HNC patients and to guide individualized decision-making on thromboprophylaxis.


Assuntos
Neoplasias de Cabeça e Pescoço , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Estudos Retrospectivos , Anticoagulantes/uso terapêutico , Estudos Transversais , Medição de Risco , Nomogramas , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/terapia
9.
PLoS One ; 18(6): e0285425, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37294818

RESUMO

The disordered mining of Dabaoshan lead-zinc mineral resources in Shaoguan has brought serious harm to the regional ecological environment. In order to investigate the heavy metal pollution status and microbial characteristics of soil plant system in mining area, The distribution of heavy metals in the soil, the activity of soil microorganisms and the accumulation characteristics of heavy metals in the dominant plant Miscanthus floridulus were studied. The results indicated that metal element contents of Miscanthus floridulus in sequence were: Zn>Pb>Cu> Cd. This study demonstrated that the elemental content of the Miscanthus floridulus plant showed Zn>Pb>Cu>Cd, with Zn being the most significantly correlated with soil elements, followed by Pb. Compared with the control group, the Miscanthus floridulus-soil system possessed obviously different soil microbial features: intensiver in microbial basal respiration strength, and higher microbial eco-physiological parameters Cmic/Corg and qCO2, but lower in soil microbial biomass. The results showed the soil enzymatic activities decreased significantly with increase of contamination of heavy metals, especially dehydrogenase and urease activities. With the increase of the content of heavy metals in the mining area soil, the intensity of soil biochemical action in the mining area (Q1, Q2) soil decreased significantly, and the biochemical action showed a significant negative correlation with the content of heavy metals in the soil. Compared with the non mining area (Q8) soil, the intensity of soil ammonification, nitrification, N fixation and cellulose decomposition decreased by 43.2%~71.1%, 70.1%~92.1%, 58.7%~87.8% and 55.3%~79.8% respectively. The decrease of soil microbial activity weakened the circulation rate and energy flow of C and N nutrients in the soil of the mining area.


Assuntos
Metais Pesados , Poluentes do Solo , Solo/química , Cádmio/análise , Chumbo , Poluentes do Solo/análise , Metais Pesados/análise , Plantas , Poaceae , China , Monitoramento Ambiental , Medição de Risco
10.
Sci Total Environ ; 860: 160520, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36442628

RESUMO

Significant upward trends in surface ozone (O3) have been widely reported in China during recent years, especially during warm seasons in the North China Plain (NCP), exerting adverse environmental effects on human health and agriculture. Quantifying long-term O3 variations and their attributions helps to understand the causes of regional O3 pollution and to formulate according control strategy. In this study, we present long-term trends of O3 in the warm seasons (April-September) during 2006-2019 at an agricultural site in the NCP and investigate the relative contributions of meteorological and anthropogenic factors. Overall, the maximum daily 8-h average (MDA8) O3 exhibited a weak decreasing trend with large interannual variability. < 6 % of the observed trend could be explained by changes in meteorological conditions, while the remaining 94 % was attributed to anthropogenic impacts. However, the interannual variability of warm season MDA8 O3 was driven by both meteorology (36 ± 28 %) and anthropogenic factors (64 ± 27 %). Daily maximum temperature was the most essential factor affecting O3 variations, followed by ultraviolet radiation b (UVB) and boundary layer height (BLH), with rising temperature trends inducing O3 inclines throughout April to August, while UVB mainly influenced O3 during summer months. Under changes in emissions and air quality, warm season O3 production regime gradually shifted from dominantly VOCs-limited during 2006-2015 to NOx-limited afterwards. Relatively steady HCHO and remarkably rising NOx levels resulted in the fast decreasing MDA8 O3 (-2.87 ppb yr-1) during 2006-2012. Rapidly decreasing NOx, flat or slightly increasing HCHO promoted O3 increases during 2012-2015 (9.76 ppb yr-1). While afterwards, slow increases in HCHO and downwards fluctuating NOx led to decreases in MDA8 O3 (-4.97 ppb yr-1). Additionally, continuous warming trends might promote natural emissions of O3 precursors and magnify their impacts on agricultural O3 by inducing high variability, which would require even more anthropogenic reduction to compensate for.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Humanos , Ozônio/análise , Poluentes Atmosféricos/análise , Meteorologia , Raios Ultravioleta , Monitoramento Ambiental/métodos , Poluição do Ar/análise , China
11.
Rep Pract Oncol Radiother ; 28(6): 809-822, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38515813

RESUMO

Background: This article aimed to compile and summarize clinically relevant literature in radiation therapy, and to discuss the potential in radioresistant and radiosensitive head and neck cancer. Study Design: Narrative review. Materials and methods: Google Scholar, PubMed and the Cochrane Library were retrieved using combined key words such as "radiotherapy" and "head and neck cancer". Search strings additionally queried were "radioresistant", "radiosensitive", "head and neck region", "squamous cell carcinoma", in combination with Boolean Operators 'AND' and 'OR'. Subsequently, the resulting publications were included for review of the full text. Results: Radiotherapeutic response currently in clinical observation referred to HNSCC scoping were selected into this review. The compiled mechanisms were then detailed concerning on the clinical significance, biological characteristics, and molecular function. Conclusions: Brachytherapy or/and external-beam radiotherapy are crucial for treating HNSCC, especially the early stage patients, but in patients with locally advanced tumors, their outcome with radiation therapy is poor due to obvious radioresistance. The curative effects mainly depend on the response of radiation therapy, so an updated review is needed to optimize further applications in HNSCC radiotherapy.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35675240

RESUMO

In this study, we investigate the event-triggering time-varying trajectory bipartite formation tracking problem for a class of unknown nonaffine nonlinear discrete-time multiagent systems (MASs). We first obtain an equivalent linear data model with a dynamic parameter of each agent by employing the pseudo-partial-derivative technique. Then, we propose an event-triggered distributed model-free adaptive iterative learning bipartite formation control scheme by using the input/output data of MASs without employing either the plant structure or any knowledge of the dynamics. To improve the flexibility and network communication resource utilization, we construct an observer-based event-triggering mechanism with a dead-zone operator. Furthermore, we rigorously prove the convergence of the proposed algorithm, where each agent's time-varying trajectory bipartite formation tracking error is reduced to a small range around zero. Finally, four simulation studies further validate the designed control approach's effectiveness, demonstrating that the proposed scheme is also suitable for the homogeneous MASs to achieve time-varying trajectory bipartite formation tracking.

13.
Comput Math Methods Med ; 2022: 3331119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720042

RESUMO

Objective: To explore the effects of fibroblast growth factor 3 (FGF3) on the proliferation, cell cycle, and apoptosis of the tongue squamous cell carcinoma SCC-9 cell line (SCC-9). Methods: We measured the proliferation of SCC-9 cells in a control group, an FGF3 intervention group, and a fibroblast growth factor (FGFR) inhibitor intervention group in cholecystokinin octapeptide (CCK-8) experiments. We studied effects of FGF3 on the cell cycle and apoptosis of tongue cancer cells using flow cytometry. We further explored the IRS1/PI3K/AKT signaling pathway by measuring BCL-2 and Bcl-2 Associated X-protein (BAX) mRNA and protein levels with RT-PCR and western blot, respectively. Results: Results from the CCK-8 experiment showed that survival rates of cells in the control group, FGF3 intervention group, and FGFR inhibitor intervention group were 100.000% ± 4.026%, 136.330% ± 9.779%, and 83.199% ± 4.954%, respectively; survival rates of SCC-9 cells in all three groups were statistically significant (P < 0.05). Compared with that in the control group, the ratio of cells in G0/G1 phase in the FGFR inhibitor intervention group was higher (P < 0.05) and that in G2/M phase was lower, while the FGF3 intervention group showed opposite results (P < 0.05). The apoptosis rate of tongue cancer cells differed significantly between the FGFR inhibitor intervention and the control groups (P < 0.05). The mRNA and protein expression levels of IRS1, PI3K, and BCL-2 were all increased in the FGF3 intervention group (P < 0.05), while BAX mRNA and protein expression levels were decreased (P < 0.05). The mRNA expression levels of protein kinase B (AKT) showed no differences between groups. The p-AKT protein was overexpressed, while the total amount of AKT protein remained stable (P < 0.05). Conclusion: FGF3 contributes to the proliferation of SCC-9 cells by increasing the proportion of cells in G2/M phase. Therefore, appropriately timed inhibition of FGF3 can potentially promote tumor apoptosis through the IRS1/PI3K/AKT signaling pathway. Our results demonstrate the role of FGF3 in the tumor microenvironment in tongue squamous cell carcinoma SCC-9 cells and suggest new therapeutic targets.


Assuntos
Carcinoma de Células Escamosas , Neoplasias da Língua , Apoptose/genética , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Fator 3 de Crescimento de Fibroblastos/farmacologia , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/uso terapêutico , RNA Mensageiro/genética , Sincalida/farmacologia , Sincalida/uso terapêutico , Língua , Neoplasias da Língua/tratamento farmacológico , Neoplasias da Língua/genética , Neoplasias da Língua/patologia , Microambiente Tumoral , Proteína X Associada a bcl-2/farmacologia
14.
Environ Res ; 208: 112672, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34999028

RESUMO

Regional transport is a key source of carbonaceous aerosol in many Chinese megacities including Beijing. The sources of carbonaceous aerosol in urban areas have been studied extensively but are poorly known in upwind rural areas. This work aims to quantify the contributions of fossil and non-fossil fuel emissions to carbonaceous aerosols at a rural site in North China Plain in winter 2016. We integrated online high resolution-time of flight-aerosol mass spectrometer (HR-TOF-AMS) observations and radiocarbon (14C) measurements of fine particles with Positive Matrix Factorization (PMF) analysis as well as Extended Gelencsér (EG) method. We found that fine particle concentration is much higher at the rural site than in Beijing during the campaign (Dec 7, 2016 to Jan 8, 2017). PMF analysis of the AMS data showed that coal-combustion related organic aerosol (CCOA + Oxidized CCOA) and more oxidized oxygenated organic aerosol (MO-OOA) contributed 48% and 30% of organic matter to non-refractory PM1 (NR-PM1) mass. About 2/3 of the OC and EC were from fossil-fuel combustion. The EG method, combining AMS-PMF and 14C data, showed that primary and secondary OC from fossil fuel contribute 35% and 22% to total carbon (TC), coal combustion emission dominates the fossil fuel sources, and biomass burning accounted for 21% of carbonaceous aerosol. In summary, our results confirm that fossil fuel combustion was the dominant source of carbonaceous aerosol during heavy pollution events in the rural areas. Significant emissions of solid fuel carbonaceous aerosols at rural areas can affect air quality in downwind cities such as Beijing and Tianjin, highlighting the benefits of energy transition from solid fuels to cleaner energy in rural areas.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , China , Monitoramento Ambiental/métodos , Combustíveis Fósseis , Fósseis , Material Particulado/análise , Estações do Ano
15.
Sci Total Environ ; 760: 143394, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33221018

RESUMO

Submicron particle matter (PM1) that rapidly reaches exceedingly high levels in several or more hours in the North China Plain (NCP) has been threating~400 million individuals' health for decades. The precise cause of the rapid rise in PM1 remains uncertain. Based on sophisticated measurements in PM1 characterizations and corresponding boundary-layer (BL) meteorology in the NCP, it demonstrates that this rising is mainly driven by BL meteorological variability. Large increases in near-ground inversions and decreases in vertical heat/momentum fluxes during the day-night transition result in a significant reduction in mixing space. The PM1 that is vertically distributed before accumulates at the near-ground and then experiences a rapid rise. Besides meteorological variability, a part of the rise in organics is ascribed to an increase of coal combustion at midnight. The daily-based accumulation of PM1 is attributed to day-to-day vertical meteorological variability, particularly diminishing mixing layer height exacerbated by aerosol-radiation feedback. Resolved by a multiple linear regression model, BL meteorological variability can explain 71% variances of PM1. In contrast, secondary chemical reactions facilitate the daily-based accumulation of PM1 rather than the rapid rise. Our results show that BL meteorological variability plays a dominant role in PM1 rising and day-to-day accumulation, which is crucial for understanding the mechanism of heavy pollution formation.

16.
Transl Cancer Res ; 10(1): 520-528, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35116281

RESUMO

BACKGROUND: To investigate the effects of long non-coding RNA HOX transcript antisense intergenic RNA (lncHOTAIR) on the proliferation and migration of Tca-8113 cells and TSCCA cells, as well as the epithelial-mesenchymal transition (EMT), and Notch signaling pathway. To further explore the role of HOTAIR in the development of tongue cancer. METHODS: Transfection was performed on Tca8113 cells using siRNA to knock down the expression of HOTAIR. 3-(4, 5-dimethylthiazole-2-yl)-2, 5-diphenyltetrazole-2, 5-diphenyltetrazole-2, bromination method (MTT) was used to determine the proliferation of the experimental group and the control group. And cellular migration and invasion was evaluated using Transwell assay. Western blot analysis was performed to determine the EMT related protein expression, together with the Notch signaling pathway related protein such as Jagged-1, Notch-1, and Hes-1. RESULTS: The proliferation of cancer cells was inhibited after silencing with small interfering (si)RNA. The invasion and migration of cancer cells was inhibited after silencing with small interfering (si)RNA (P<0.01). The expression of Jagged-1, Notch-1, and Hes-1 protein in the transfected HOTAIR siRNA cells was substantial decreased compared with the control (P<0.05). CONCLUSIONS: It is possible that lncHOTAIR contributes to the invasion and metastasis of Tca-8113 and TSCCA cells, which may be related to the EMT. There may be an involvement of HOTAIR in the pathogenesis of tongue cancer through modulation of the Notch signaling pathway.

17.
Environ Sci Technol ; 54(24): 15710-15721, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33237756

RESUMO

Secondary aerosol (SA) frequently drives severe haze formation on the North China Plain. However, previous studies mostly focused on submicron SA formation, thus our understanding of SA formation on supermicron particles remains poor. In this study, PM2.5 chemical composition and PM10 number size distribution measurements revealed that the SA formation occurred in very distinct size ranges. In particular, SA formation on dust-dominated supermicron particles was surprisingly high and increased with relative humidity (RH). SA formed on supermicron aerosols reached comparable levels with that on submicron particles during evolutionary stages of haze episodes. These results suggested that dust particles served as a medium for rapid secondary organic and inorganic aerosol formation under favorable photochemical and RH conditions in a highly polluted environment. Further analysis indicated that SA formation pathways differed among distinct size ranges. Overall, our study highlights the importance of dust in SA formation during non-dust storm periods and the urgent need to perform size-resolved aerosol chemical and physical property measurements in future SA formation investigations that are extended to the coarse mode because the large amount of SA formed thereon might have significant impacts on ice nucleation, radiative forcing, and human health.


Assuntos
Poluentes Atmosféricos , Poeira , Aerossóis/análise , Poluentes Atmosféricos/análise , China , Poeira/análise , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Material Particulado/análise , Estações do Ano
18.
Sensors (Basel) ; 20(15)2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32726953

RESUMO

This paper proposes a distributed model-free adaptive bipartite consensus tracking (DMFABCT) scheme. The proposed scheme is independent of a precise mathematical model, but can achieve both bipartite time-invariant and time-varying trajectory tracking for unknown dynamic discrete-time heterogeneous multi-agent systems (MASs) with switching topology and coopetition networks. The main innovation of this algorithm is to estimate an equivalent dynamic linearization data model by the pseudo partial derivative (PPD) approach, where only the input-output (I/O) data of each agent is required, and the cooperative interactions among agents are investigated. The rigorous proof of the convergent property is given for DMFABCT, which reveals that the trajectories error can be reduced. Finally, three simulations results show that the novel DMFABCT scheme is effective and robust for unknown heterogeneous discrete-time MASs with switching topologies to complete bipartite consensus tracking tasks.

19.
Environ Pollut ; 257: 113621, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761581

RESUMO

Atmospheric ammonia (NH3) as the most important alkaline gas in the atmosphere has attracted much attention in recent years due to its critical role in haze formation, especially on the North China Plain (NCP). Comprehensive studies are needed for investigating diurnal variations of NH3 and underlying mechanisms in different seasons and their potential impacts on atmospheric chemistry. In this study, continuous long-term observation (Mar. 2016 to May 2017) of NH3 at a rural site in the NCP was used to characterize the diurnal variation of NH3 in different seasons and to unveil its causes and potential impacts on atmospheric chemistry. NH3 concentrations displayed rapid increases during the morning, reaching very prominent peaks mostly between 8:00 to 11:00 LT. Such frequent (55%) morning peaks were mainly caused by the evaporation of dew and guttation water droplets. Average dew and guttation water volume concentrations of 750 mL m-2 was estimated for spring, which resulted in approximate NH3 emissions of 800 ng m-2 s- 1. Such high emission fluxes from dew and guttation water evaporation have never been reported before, suggesting dew and guttation droplets to be significant night-time reservoirs and strong morning sources for NH3. In light of recent studies putting forward that NH3 can promote the heterogeneous formation of HONO and nitrate under high humidity conditions, we investigated the differences in HONO and aerosol chemical composition diurnal variations between days with and without NH3 morning spikes during November. HONO, nitrate and sulfate concentrations were significantly higher for days with NH3 morning spikes, with HONO displaying a morning peak near that of NH3. These results demonstrate that the prevailing NH3 morning spikes on the NCP have significant influences on aerosol formation and atmospheric chemistry. NH3 emission mitigation strategies and regulations are urgently needed.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Amônia/análise , Monitoramento Ambiental , China
20.
Sensors (Basel) ; 18(11)2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30445752

RESUMO

The fraction of absorbed photosynthetically active radiation (FPAR) is a key variable in the model of vegetation productivity. Vegetation indices (VIs) that were derived from instantaneous remote-sensing data have been successfully used to estimate the FPAR of a day or a longer period. However, it has not yet been verified whether continuous VIs can be used to accurately estimate the diurnal dynamics of a vegetation canopy FPAR, which may fluctuate dramatically within a day. In this study, we measured the high temporal resolution spectral data (480 to 850 nm) and FPAR data of a maize canopy from the jointing stage to the tasseling stage under different irrigation and illumination conditions using two automatic observation systems. To estimate the FPAR, we developed regression models based on a quadratic function using 13 kinds of VIs. The results show the following: (1) Under nondrought conditions, although the illumination condition (sunny or cloudy) influenced the trend of the canopy diurnal FPAR, it had only a slight effect on the model accuracies of the FPAR-VIs. The maximum coefficients of determination (R²) of the FPAR-VIs models generated for the sunny nondrought data, the cloudy nondrought data, and all of the nondrought data were 0.895, 0.88, and 0.828, respectively. The VIs-including normalized difference vegetation index (NDVI), green NDVI (GNDVI), red-edge simple ratio (SR705), modified simple ratio 2 (mSR2), red-edge normalized difference vegetation index (NDVI705), and enhanced vegetation index (EVI)-that were related to the canopy structure had higher estimation accuracies (R² > 0.8) than the other VIs that were related to the soil adjustment, chlorophyll, and physiology. The estimation accuracies of the GNDVI and some red-edge VIs (including NDVI705, SR705, and mSR2) were higher than the estimation accuracy of the NDVI. (2) Under drought stress, the FPAR decreased significantly because of leaf wilting and the effective leaf area index decrease around noon. When we included drought data in the model, accuracies were reduced dramatically and the R² value of the best model was only 0.59. When we built the regression models based only on drought data, the EVI, which can weaken the influence of soil, had the best estimate accuracy (R² = 0.68).


Assuntos
Clorofila/metabolismo , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Zea mays/fisiologia , Desidratação , Luz , Folhas de Planta/química , Solo/química
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