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1.
Cell Death Dis ; 15(1): 11, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182570

RESUMO

Emerging evidence indicates that protein activities regulated by receptor protein tyrosine phosphatases (RPTPs) are crucial for a variety of cellular processes, such as proliferation, apoptosis, and immunological response. Protein tyrosine phosphatase receptor type O (PTPRO), an RPTP, has been revealed as a putative suppressor in the development of particular tumors. However, the function and the underlying mechanisms of PTPRO in regulating of lung adenocarcinoma (LUAD) are not well understood. In this view, the present work investigated the role of PTPRO in LUAD. Analysis of 90 pairs of clinical LUAD specimens revealed significantly lower PTPRO levels in LUAD compared with adjacent non-tumor tissue, as well as a negative correlation of PTPRO expression with tumor size and TNM stage. Survival analyses demonstrated that PTPRO level can help stratify the prognosis of LUAD patients. Furthermore, PTPRO overexpression was found to suppress the progression of LUAD both in vitro and in vivo by inducing cell death via mitochondria-dependent apoptosis, downregulating protein expression of molecules (Bcl-2, Bax, caspase 3, cleaved-caspase 3/9, cleaved-PARP and Bid) essential in cell survival. Additionally, PTPRO decreased LUAD migration and invasion by regulating proteins involved in the epithelial-to-mesenchymal transition (E-cadherin, N-cadherin, and Snail). Moreover, PTPRO was shown to restrain JAK2/STAT3 signaling pathways. Expression of PTPRO was negatively correlated with p-JAK2, p-STAT3, Bcl-2, and Snail levels in LUAD tumor samples. Furthermore, the anti-tumor effect of PTPRO in LUAD was significant but compromised in STAT3-deficient cells. These data support the remarkable suppressive role of PTPRO in LUAD, which may represent a viable therapeutic target for LUAD patients.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores , Humanos , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Apoptose , Caspase 3 , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mitocôndrias , Monoéster Fosfórico Hidrolases , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo
2.
BMJ Open ; 13(11): e071959, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38011986

RESUMO

INTRODUCTION: Compensatory mouth breathing, caused by nasopharyngeal obstructive diseases, is the main cause of hyperdivergent mandibular retrognathia in children. Such deformities require effective growth guidance before pubertal growth peaks. The traditional mandibular advancement device, twin block (TB), can guide the forward development of the mandible. However, the side effect of increasing the vertical dimension of the lower facial third, worsens the facial profile of children with divergent growth trends. To solve this problem, a modified TB (LLTB) appliance was designed to control the vertical dimension by intruding incisors and inhibiting the elongation of posterior teeth during the advancement of the mandible, which could avoid the side effects of traditional appliances and effectively guide the growth of the mandible in a normal direction. METHODS AND ANALYSIS: The study was designed as a single-centre, single-blind, randomised, parallel controlled trial. We aim to enrol 60 children aged 9-14 years with hyperdivergent skeletal class II malocclusion, using a 1:1 allocation ratio. The participants were will be randomly assigned to receive either the TB or LLTB treatment. The primary outcome will be a change in the angle of the mandibular plane relative to the anterior cranial base. The secondary outcomes will include changes in the sagittal maxillomandibular relation, occlusal plane, facial height, morphology of the mandible and upper airway width. Safety endpoints will also be evaluated. ETHICS AND DISSEMINATION: Ethical approval was obtained from the ethics committee of Shanghai Stomatological Hospital. Both participants and their guardians will be fully informed of the study and sign an informed consent form before participating in the trial. The results will be publicly available in peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: ChiCTR2000035882.


Assuntos
Aparelhos Ortodônticos Funcionais , Retrognatismo , Humanos , Criança , Retrognatismo/terapia , Método Simples-Cego , Cefalometria/métodos , China , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Front Oncol ; 13: 1103169, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37274245

RESUMO

Introduction: Primary pulmonary lymphoepithelioma-like carcinoma (PPLELC) is a rare histological type of non-small cell lung cancer (NSCLC), which accounts for less than 1% of NSCLC. Currently, there is no well-recognized treatment guideline for PPLELC. Methods: We identified PPLELC patients from the Surveillance, Epidemiology, and End Results (SEER) dataset between 2000 and 2015 (n = 72) as well as from our medical center between 2014 and 2020 (n = 16). All diagnoses were confirmed by pathological testing, and the clinicopathological characteristics of patients were retrieved and summarized. Survival analyses were conducted using the Kaplan-Meier analysis and log-rank tests. Multivariate survival analysis was performed with the Cox regression hazards model. Results: The median age at diagnosis of the PPLELC cohort was 64 years, ranging from 15 to 86 years. The percentages of patients with TNM stages I, II, III, and IV were 52.3%, 10.2%, 20.5%, and 17.0%, respectively. Among the 88 cases, lesion resection was performed in 69 cases (78.4%), 16 cases (18.1%) received beam radiation, and 40 cases (45.5%) underwent chemotherapy. In the SEER dataset of lung cancer, the percentage of PPLELC in the Asian race (0.528‰) was almost 10 times higher than that in the white (0.065‰) and black (0.056‰) races. Patients with TNM stage III-IV exhibited a worse prognosis than those with TNM stage I-II (p = 0.008), with a 5-year cancer-specific survival (CSS) rate of 81.8% for TNM stage I-II and 56.2% for TNM stage III-IV. Specifically, the N stage and M stage were the leading prognostic factors, not the T stage and tumor size. Moreover, patients who underwent surgery had significantly better outcomes than those who did not (p = 0.014). Additional multivariate analysis indicated that the TNM stage was an independent prognosis factor for CSS (HR, 3.31; 95% CI, 1.08-10.14). Conclusion: PPLELC is a rare tumor with Asian susceptibility. Although the prognosis of PPLELC is better than that of other subtypes of NSCLC, it remains unsatisfactory for advanced-stage disease. The current treatment options for PPLELC include surgical resection, chemotherapy, radiotherapy, and immune therapy. Among these options, patients with surgical resection have better survival rates in this study. However, large-scale clinical research trials will be necessary to develop effective treatment guidelines for PPLELC.

4.
Huan Jing Ke Xue ; 44(5): 2450-2460, 2023 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-37177920

RESUMO

As the most important absorbing aerosol, black carbon (BC) can affect radiation, clouds, and surface snow cover over the Tibetan Plateau. In this study, the BC mass concentrations were measured using a seven-channel aethalometer (AE-33) in Litang County over the eastern Tibetan Plateau from July 5 to September 5, 2017. The aethalometer model, potential source contribution function (PSCF), and concentration-weighted trajectory (CWT) models were used to analyze the variation characteristics, potential sources, and affecting areas of BC. The results showed that the mass concentration of ρ(BC) in Litang ranged from 0.4 to 4699.8 ng·m-3, with an average value of 816.4 ng·m-3, accounting for 5.96% of PM2.5. The average mass concentrations of ρ(BCliquid) and ρ(BCsolid) in Litang were 486.1 ng·m-3 and 398.5 ng·m-3, respectively, with a C of 0.51. The ρ(BC) mass concentration was mainly distributed from 0-2000 ng·m-3, which accounted for 92.5% of the total observation period. The diurnal variation in BC, BCliquid, and BCsolid showed a bimodal distribution, with the peaks appearing at 08:00 and 20:00, respectively. The first peak was mainly related to traffic sources and incomplete combustion of carbonaceous materials, whereas the second peak was mainly related to incomplete combustion of carbonaceous materials. The potential sources and affecting areas of PM2.5 and BC were different. Imports from abroad had a greater impact on the concentrations of PM2.5 and BC in Litang, and the affecting areas were mainly transmitted to the northeast in China. The high-value centers were mainly concentrated in the surrounding areas of Litang.

5.
Huan Jing Ke Xue ; 44(1): 66-74, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635796

RESUMO

Based on the sounding data of VOCs in the lower troposphere (0-1000 m) in the northern suburb of Nanjing in the autumn of 2020, the vertical profile distribution, diurnal variation, and photochemical reactivity of VOCs in this area were analyzed. The results showed that the volume fraction of VOCs decreased with the increase in height (72.1×10-9±28.1×10-9-56.4×10-9±24.8×10-9). Alkanes at all heights accounted for the largest proportion (68%-75%), followed by aromatics (10%-12%), halohydrocarbons (10%-11%), alkenes (3%-7%), and acetylene (2%). The diurnal variation of the boundary layer had a great influence on the VOCs profile. The lower boundary layer in the morning and evening caused the volume fraction of VOCs to accumulate near the ground and lower in the upper layer. The vertical distribution of VOCs was more uniform in the afternoon. In the morning, the volume fraction proportion of alkenes (alkanes) with strong (weak) photochemical reactivity decreased (increased) with the increase in height, indicating that the photochemical aging of VOCs in the upper layer was significant. In the afternoon, the vertical distribution of VOCs volume fraction and OFP in the lower troposphere were more uniform. Affected by the surrounding air masses with different sources, the volume fraction and component proportion of VOCs at each height were significantly different. The alkanes in rural air masses were vertically evenly distributed, and the proportion increased gradually with the height. The vertical negative gradient of VOCs volume fraction in the urban air mass was the largest, the volume fraction of VOCs near the ground was high, and it was rich in aromatics. The proportion of aromatics increased with the increase in VOCs volume fraction between 200-400 m height of industrial air mass. The near-surface VOCs volume fraction of the highway traffic air mass was high, and alkanes accounted for the largest proportion.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Monitoramento Ambiental , Alcenos/análise , Alcanos/análise , China , Ozônio/análise
6.
J Cancer Res Clin Oncol ; 149(7): 3349-3360, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35941228

RESUMO

PURPOSE: Uveal melanoma (UM) is the most common intraocular malignant tumor in adults. Due to the lack of effective treatments for metastatic UM, the survival of UM has not changed over the past 3 decades. Therefore, it is important to identify essential genes regulating the metastasis of UM. METHODS: In this study, a genome-wide CRISPR knockout screen in an orthotopic mouse model of UM was performed to identify the regulatory genes conferring the metastatic phenotype. Loss-of-function analyses were performed to explore the function of G protein pathway suppressor 2 (GPS2) in UM metastasis in vitro and in vivo. RNA sequencing was performed to investigate the molecular mechanism underlying the function of GPS2 as a tumor suppressor in UM. RESULTS: Among the highest-ranking genes, we found several validated tumor suppressors, such as SHPRH, GPS2, PRPH2, and hsa-mir-1229; GPS2 was chosen as the candidate gene for further studies. GPS2 was lower expressed in the tumor tissues of UM patients. Furthermore, knocking-down GPS2 promoted the proliferation and metastatic abilities of UM cells both in vivo and in vitro. Finally, analysis of the transcriptome data revealed that silencing GPS2 upregulates oncogenic signaling pathways MAPK and PI3K-Akt, and in the meantime downregulates tumor suppressor signaling pathway Slit/Robo in UM cells. CONCLUSION: Altogether, our study proved that the GPS2 gene functions as a tumor suppressor and might be a novel potential therapeutic target for UM treatment.


Assuntos
Melanoma , Neoplasias Uveais , Animais , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Melanoma/patologia , Neoplasias Uveais/patologia , Genes Reguladores , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Linhagem Celular Tumoral , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
7.
Entropy (Basel) ; 24(11)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36359622

RESUMO

On the basis of the established irreversible simple closed gas turbine cycle model, this paper optimizes cycle performance further by applying the theory of finite-time thermodynamics. Dimensionless efficient power expression of the cycle is derived. Effects of internal irreversibility (turbine and compressor efficiencies) and heat reservoir temperature ratio on dimensionless efficient power are analyzed. When total heat conductance of two heat exchangers is constant, the double maximum dimensionless efficient power of a cycle can be obtained by optimizing heat-conductance distribution and cycle pressure-ratio. Through the NSGA-II algorithm, multi-objective optimizations are performed on the irreversible closed gas turbine cycle by taking five performance indicators, dimensionless power density, dimensionless ecological function, thermal efficiency, dimensionless efficient power and dimensionless power output, as objective functions, and taking pressure ratio and heat conductance distribution as optimization variables. The Pareto frontiers with the optimal solution set are obtained. The results reflect that heat reservoir temperature ratio and compressor efficiency have greatest influences on dimensionless efficient power, and the deviation indexes obtained by TOPSIS, LINMAP and Shannon Entropy decision-making methods are 0.2921, 0.2921, 0.2284, respectively, for five-objective optimization. The deviation index obtained by Shannon Entropy decision-making method is smaller than other decision-making methods and its result is more ideal.

8.
Environ Res ; 214(Pt 4): 114095, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36037924

RESUMO

Since the Air Pollution Prevention and Control Action Plan (air clean plan) issued in 2013, air quality has been in continuous improvement. The second stage of air clean plan since 2018 was focused on O3 controlling, but it still didn't decline so significantly as PM2.5. This study conducted a long-term observation on black carbon (BC) and utilized the observational data of other air pollutants (PM2.5, PM10, NO2, SO2, CO and O3), the meteorological elements and the vertical sounding data of PBL in Nanjing. In the daytime (08:00-20:00), PM2.5 kept decreasing from 2015 to 2020 at the rate of 4.8 µg⋅m-3⋅a-1, however, BC increased at the rate of 0.6 µg⋅m-3⋅a-1, which has led to the continuous growth of BC/PM2.5 (0.9%⋅a-1). However, during this period, O3 was relatively stable and, in 2020, it returned below its value in 2015 after slight increases in 2017 and 2018. Meanwhile, the average surface temperature had increased by around 1.0 °C during 2015-2019 at the rate of 0.3 °C⋅a-1. Also, the average height of the inversion layer had increased significantly by 494.0 and 176.7 m at 20:00 and 08:00, whose growth ratio was up to 57% and 25%, respectively. The above observation results have formed a set of chain reactions as follows. The growth of the surface BC caused the surface temperature to rise due to the increasing heating effect of BC. The continuous growth of the surface temperature made it easier for the PBL height to develop, which led to the lift of the inversion layer in the PBL and the larger atmospheric environment capacity. Ultimately, it is conducive to the diffusion of the near surface pollutants, thus helping reduce their concentrations, which offsets the increasing tendency of O3 and add to the decreasing trend of PM2.5. This phenomenon is the most remarkable in summer, with the fastest increasing rate of temperature (0.8 °C⋅a-1) and O3 (3.9 µg⋅m-3⋅a-1) during 2015-2019 (excluding 2020 to erase the great effect of COVID-19 lockdown on emissions).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , COVID-19/epidemiologia , COVID-19/prevenção & controle , Carbono , China , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Material Particulado/análise , Rios , Fuligem
9.
Entropy (Basel) ; 24(8)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-36010738

RESUMO

Considering that the specific heat of the working fluid varies linearly with its temperature, this paper applies finite time thermodynamic theory and NSGA-II to conduct thermodynamic analysis and multi-objective optimization for irreversible porous medium cycle. The effects of working fluid's variable-specific heat characteristics, heat transfer, friction and internal irreversibility losses on cycle power density and ecological function characteristics are analyzed. The relationship between power density and ecological function versus compression ratio or thermal efficiency are obtained. When operating in the circumstances of maximum power density, the thermal efficiency of the porous medium cycle engine is higher and its size is less than when operating in the circumstances of maximum power output, and it is also more efficient when operating in the circumstances of maximum ecological function. The four objectives of dimensionless power density, dimensionless power output, thermal efficiency and dimensionless ecological function are optimized simultaneously, and the Pareto front with a set of solutions is obtained. The best results are obtained in two-objective optimization, targeting power output and thermal efficiency, which indicates that the optimal results of the multi-objective are better than that of one-objective.

10.
Dis Markers ; 2022: 8323946, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937945

RESUMO

During Graves' disease (GD) treatment, Graves' ophthalmopathy (GO) is often ignored because only mild ocular symptoms are present in early GD. Therefore, we performed isobaric tags for relative and absolute quantification (iTRAQ) analysis and measured relevant endocrine hormones to identify predisposing factors of GO. Serum samples from 3 patients with mild GD and GO and 3 patients with GD but without GO were analyzed by iTRAQ. Based on their clinical data, 60 patients with GD were divided into the GO-free and GO groups. All patients were followed up for 7 months. Their eye conditions and changes in related biochemical indexes were recorded. The iTRAQ results showed that RhoA expression was upregulated and correlated significantly with the tight junction pathway and immunity. The changes in FT3 and RhoA from baseline to 7 months, the FT3 and RhoA baseline levels, and the TRAb titer levels in patients with GD significantly differed between the groups. ELISA and western blotting for RhoA, TRAb, and FT3 in the serum samples from GO patients showed significant upregulation, as well as elevated serum RhoA and TRAb levels in the mild stage of GO. At 7 months, the serum RhoA and FT3 levels were elevated. RhoA is a potential biomarker for mild GO. In GD patients, if an elevated serum RhoA level is accompanied by an elevated TRAb or FT3 level, GO is highly likely to occur, even when obvious ocular symptoms are absent.


Assuntos
Doença de Graves , Oftalmopatia de Graves , Biomarcadores , Ensaio de Imunoadsorção Enzimática , Doença de Graves/diagnóstico , Doença de Graves/tratamento farmacológico , Oftalmopatia de Graves/diagnóstico , Humanos , Proteína rhoA de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/uso terapêutico
11.
Entropy (Basel) ; 24(10)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37420423

RESUMO

Based on the quadrilateral heat generation body (HGB) proposed by previous literature, the multi-objective constructal design is performed. Firstly, the constructal design is performed by minimizing the complex function composed of the maximum temperature difference (MTD) and entropy generation rate (EGR), and the influence of the weighting coefficient (a0) on the optimal constructal is studied. Secondly, the multi-objective optimization (MOO) with the MTD and EGR as optimization objectives is performed, and the Pareto frontier with an optimal set is obtained by using NSGA-II. The optimization results are selected from the Pareto frontier through LINMAP, TOPSIS, and Shannon Entropy decision methods, and the deviation indexes of different objectives and decision methods are compared. The research of the quadrilateral HGB shows that the optimal constructal can be gained by minimizing the complex function with the objectives of the MTD and the EGR, the complex function after the constructal design is reduced by up to 2% compared with its initial value, and the complex function of the two reflects the compromise between the maximum thermal resistance and the irreversible loss of heat transfer. The Pareto frontier includes the optimization results of different objectives, and when the weighting coefficient of a complex function changes, the optimization results obtained by minimizing the complex function will also be distributed in the Pareto frontier. The deviation index of the TOPSIS decision method is 0.127, which is the lowest one among the discussed decision methods.

12.
Entropy (Basel) ; 24(10)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37420463

RESUMO

Two-stage thermoelectric generators have been widely used in the aerospace, military, industrial and daily life fields. Based on the established two-stage thermoelectric generator model, this paper further studies its performance. Applying the theory of finite-time thermodynamics, the efficient power expression of the two-stage thermoelectric generator is deduced firstly. The maximum efficient power is obtained secondly by optimizing the distribution of the heat exchanger area, distribution of thermoelectric elements and working current. Using the NSGA-II algorithm, multi-objective optimizations of the two-stage thermoelectric generator are performed thirdly by taking the dimensionless output power, thermal efficiency and dimensionless efficient power as objective functions, and taking the distribution of the heat exchanger area, distribution of thermoelectric elements and output current as optimization variables. The Pareto frontiers with the optimal solution set are obtained. The results show that when the total number of thermoelectric elements is increased from 40 to 100, the maximum efficient power is decreased from 0.308W to 0.2381W. When the total heat exchanger area is increased from 0.03m2 to 0.09m2, the maximum efficient power is increased from 0.0603W to 0.3777W. The deviation indexes are 0.1866, 0.1866 and 0.1815 with LINMAP, TOPSIS and Shannon entropy decision-making approaches, respectively, when multi-objective optimization is performed on three-objective optimization. The deviation indexes are 0.2140, 0.9429 and 0.1815 for three single-objective optimizations of maximum dimensionless output power, thermal efficiency and dimensionless efficient power, respectively.

13.
Entropy (Basel) ; 24(10)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37420465

RESUMO

According to the established model of a single resonance energy selective electron refrigerator with heat leakage in the previous literature, this paper performs multi-objective optimization with finite-time thermodynamic theory and NSGA-II algorithm. Cooling load (R¯), coefficient of performance (ε), ecological function (ECO¯), and figure of merit (χ¯) of the ESER are taken as objective functions. Energy boundary (E'/kB) and resonance width (ΔE/kB) are regarded as optimization variables and their optimal intervals are obtained. The optimal solutions of quadru-, tri-, bi-, and single-objective optimizations are obtained by selecting the minimum deviation indices with three approaches of TOPSIS, LINMAP, and Shannon Entropy; the smaller the value of deviation index, the better the result. The results show that values of E'/kB and ΔE/kB are closely related to the values of the four optimization objectives; selecting the appropriate values of the system can design the system for optimal performance. The deviation indices are 0.0812 with LINMAP and TOPSIS approaches for four-objective optimization (ECO¯-R¯-ε-χ¯), while the deviation indices are 0.1085, 0.8455, 0.1865, and 0.1780 for four single-objective optimizations of maximum ECO¯, R¯, ε, and χ¯, respectively. Compared with single-objective optimization, four-objective optimization can better take different optimization objectives into account by choosing appropriate decision-making approaches. The optimal values of E'/kB and ΔE/kB range mainly from 12 to 13, and 1.5 to 2.5, respectively, for the four-objective optimization.

14.
J Phys Chem Lett ; 12(48): 11710-11716, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34846910

RESUMO

Semiconductor nanocrystals (NCs) are emerging luminescent materials with superior optical properties. However, the light-conversion application of NCs is restricted by reabsorption-induced fluorescent quenching. Here, a NC-NC Förster resonance energy transfer (FRET) system is developed by employing large CsPbBr3 NCs as donors and CdSe/CdS NCs as acceptors. The FRET systems using toluene and octadecene as solvents show decreases of 10% and 14%, respectively, in the integrated photoluminescence (PL) intensity, far below the reabsorption loss observed in concentrated CdSe/CdS NCs (>30%) at the same color purity. Notably, we demonstrate by transient absorption measurements that the styrene-mediated FRET system involves a Dexter energy transfer process, which enables the harvesting of triplet excitons and leads to an additional PL enhancement at system level by a maximum of 40% instead of fluorescence quenching. The remarkably improved light-conversion efficiency and antiquenching property make the proposed NC-NC system superior in light down-conversion applications.

15.
Entropy (Basel) ; 23(7)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203548

RESUMO

Applying finite time thermodynamics theory and the non-dominated sorting genetic algorithm-II (NSGA-II), thermodynamic analysis and multi-objective optimization of an irreversible Diesel cycle are performed. Through numerical calculations, the impact of the cycle temperature ratio on the power density of the cycle is analyzed. The characteristic relationships among the cycle power density versus the compression ratio and thermal efficiency are obtained with three different loss issues. The thermal efficiency, the maximum specific volume (the size of the total volume of the cylinder), and the maximum pressure ratio are compared under the maximum power output and the maximum power density criteria. Using NSGA-II, single-, bi-, tri-, and quadru-objective optimizations are performed for an irreversible Diesel cycle by introducing dimensionless power output, thermal efficiency, dimensionless ecological function, and dimensionless power density as objectives, respectively. The optimal design plan is obtained by using three solution methods, that is, the linear programming technique for multidimensional analysis of preference (LINMAP), the technique for order preferences by similarity to ideal solution (TOPSIS), and Shannon entropy, to compare the results under different objective function combinations. The comparison results indicate that the deviation index of multi-objective optimization is small. When taking the dimensionless power output, dimensionless ecological function, and dimensionless power density as the objective function to perform tri-objective optimization, the LINMAP solution is used to obtain the minimum deviation index. The deviation index at this time is 0.1333, and the design scheme is closer to the ideal scheme.

16.
Nanoscale ; 13(20): 9381-9390, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34002177

RESUMO

We report a one-pot route for the synthesis of CsPbBr3 perovskite nanocrystals (PNCs) in styrene to form a glue-like polystyrene (PS) pre-polymer incorporating mono-dispersed PNCs. The pre-polymer enables solvent- and initiator-free fabricating and patterning PNC-PS light down-conversion films for liquid crystal display application. The mechanistic study reveals that the styrene molecules adsorbed on the PNC surface undergo self-initiated polymerization in the pre-polymerization process, forming stable surface capsulation over the PNCs. The PNC-PS pre-polymer and composite film display high photoluminescent quantum yield (PLQY) and resistance to air, light irradiation and water. The micropatterned PNC-PS film with a period of 1000 nm was fabricated through imprinting of the pre-polymer. The micropatterned thin film displays an enlarged viewing angle, improved light distribution and PLQY of >90%. The backlight employing the PNC-PS film displays bright green color and a wide color gamut of >120% NTSC. This solvent-free and one-pot strategy could find promising potential in the development of diverse luminescent nanocomposites to meet the requirements of micro/nano-manufacturing and high performance display application.

17.
Chem Commun (Camb) ; 57(24): 2982-2985, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33645599

RESUMO

One new combination, alkali-metal and alkaline earth-metal selenite fluoride, LiBa3Bi6(SeO3)7F11 (LBBSF) and its analogue Ba3Bi6.5(SeO3)7F10.5O0.5 (BBSF) were reported here for the first time. Unusual aliovalent cation substitution between them affected the layer thickness and made the bond strains of [SeO3] enhanced, thereby inducing greater distortions and affecting the SHG efficiencies. This work may provide thoughts for exploring new NLO materials.

18.
Sci Total Environ ; 756: 144135, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33288247

RESUMO

Owing to a lack of vertical observations, the impacts of black carbon (BC) on radiative forcing (RF) have typically been analyzed using ground observations and assumed profiles. In this study, a UAV platform was used to measure high-resolution in-situ vertical profiles of BC, fine particles (PM2.5), and relevant meteorological parameters in the boundary layer (BL). Further, a series of calculations using actual vertical profiles of BC were conducted to determine its impact on RF and heating rate (HR). The results show that the vertical distributions of BC were strongly affected by atmospheric thermodynamics and transport. Moreover. Three main types of profiles were revealed: Type I, Type II, Type III, which correspond to homogenous profiles (HO), negative gradient profiles (NG), and positive gradient profiles (PG), respectively. Types I and II were related to the diurnal evolution of the BL, and Type III was caused by surrounding emissions from high stacks and regional transport. There were no obvious differences in RF calculated for HO profiles and corresponding surface BC concentrations, unlike for NG and PG profiles. RF values calculated using surface BC concentrations led to an overestimate of 13.2 W m-2 (27.5%, surface) and 18.2 W m-2 (33.4%, atmosphere) compared to those calculated using actual NG profiles, and an underestimate of approximately 15.4 W m-2 (35.0%, surface) and 16.1 W m-2 (29.9%, atmosphere) compared to those calculated using actual PG profiles. In addition, the vertical distributions of BC HR exhibited clear sensitivity to BC profile types. Daytime PG profiles resulted in a positive vertical gradient of HR, which may strengthen temperature inversion at high altitudes. These findings indicate that calculations that use BC surface concentrations and ignore the vertical distribution of BC will lead to substantial uncertainties in the effects of BC on RF and HR.

19.
Environ Pollut ; 272: 115954, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33218767

RESUMO

Previous studies have developed a stable weather index (SWI) based on meteorological elements that adequately represent PM2.5 pollution over the North China Plain (NCP). However, the SWI performs poorly over the Yangtze River Delta (YRD) region because air pollution over this region is affected not only by stagnant weather (STAG) but also by transport (TRANS). For example, air pollutants can be transported from the NCP to the YRD by cold fronts. In this study, an obliquely rotated principal component analysis in the T-model is applied to classify the synoptic patterns of winter weather over the YRD region from 2013 to 2018. Among the four identified synoptic patterns, two of which cause TRANS, one pattern is most likely to cause STAG, and one pattern can lead to either STAG or TRANS depending on the location of high pressure around Shandong province. Due to the large contribution (63%) of TRANS to the total PM2.5 pollution events, a transport pollution index (TPI) is constructed to describe the transport features of PM2.5 pollution over the YRD region. Our results show that, when considering the SWI alone, the correlation coefficients between the SWI and ln(PM2.5) range from 0.50 to 0.57 in the main cities of the YRD. Excitingly, when considering both the TPI and SWI (TPI+SWI), the correlation coefficients increase significantly to 0.63-0.78, suggesting that TPI+SWI better reflects the wintertime PM2.5 pollution level over the YRD region. In addition, satisfactory performance in validation also suggests that TPI+SWI can increase the accuracy of evaluating and forecasting of PM2.5 pollution episodes over regions downstream of source emissions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano
20.
Entropy (Basel) ; 22(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33286919

RESUMO

Variation trends of dimensionless power density (PD) with a compression ratio and thermal efficiency (TE) are discussed according to the irreversible Atkinson cycle (AC) model established in previous literature. Then, for the fixed cycle temperature ratio, the maximum specific volume ratios, the maximum pressure ratios, and the TEs corresponding to the maximum power output (PO) and the maximum PD are compared. Finally, multi-objective optimization (MOO) of cycle performance with dimensionless PO, TE, dimensionless PD, and dimensionless ecological function (EF) as the optimization objectives and compression ratio as the optimization variable are performed by applying the non-dominated sorting genetic algorithm-II (NSGA-II). The results show that there is an optimal compression ratio which will maximize the dimensionless PD. The relation curve of the dimensionless PD and compression ratio is a parabolic-like one, and the dimensionless PD and TE is a loop-shaped one. The AC engine has smaller size and higher TE under the maximum PD condition than those of under the maximum PO condition. With the increase of TE, the dimensionless PO will decrease, the dimensionless PD will increase, and the dimensionless EF will first increase and then decrease. There is no positive ideal point in Pareto frontier. The optimal solutions by using three decision-making methods are compared. This paper analyzes the performance of the PD of the AC with three losses, and performs MOO of dimensionless PO, TE, dimensionless PD, and dimensionless EF. The new conclusions obtained have theoretical guideline value for the optimal design of actual Atkinson heat engine.

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