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1.
Nanotechnology ; 35(27)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38522106

RESUMO

Light and thermal detectors based on the laser-induced transverse voltage (LITV) effect have garnered significant interest for their rapid and broad spectral response. In this study, we prepared the La-doped SrTiO3(STO) epitaxial thin films on the 12° inclined single crystal LaAlO3(LAO) (100) substrates using our home-designed metal-organic chemical vapor deposition system. Under the illumination of a 248 nm laser, the LITV signals of LaxSr1-xTiO3films were observed and showed dependence on the La doping level, which can be explained by the changes in the light absorption coefficient, thermal conductivity, and optical penetration depth. The optimized LITV signal was observed with a peak voltage of 23.25 V and a decay time of 106 ns under the laser power density of 1.0 mJ mm-2. The high peak voltage and fast response time of LaxSr1-xTiO3show great potential in the field of light and thermal detection.

2.
J Vis Exp ; (201)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37982524

RESUMO

This study aims to solve the problem of the cell temperature rise and performance decline caused by dusty particulate matter covering the surface of the cell through the allocation of airflow velocities at the inlets of the battery cooling box under the goal of low energy consumption. We take the maximum temperature of the battery pack at a specified airflow velocity and dust-free environment as the expected temperature in a dusty environment. The maximum temperature of the battery pack in a dusty environment is solved at different inlet airflow velocities, which are the boundary conditions of the analysis model constructed in the simulation software. The arrays representing the different airflow velocity combinations of inlets are generated randomly through the optimal Latin hypercube algorithm (OLHA), where the lower and upper limits of velocities corresponding to the temperatures above the desired temperature are set in the optimization software. We establish an approximate QRSM between the velocity combination and the maximum temperature using the fitting module of the optimization software. The QRSM is optimized based on the ASAM, and the optimal result is in good agreement with the analysis result obtained by the simulation software. After optimization, the flow rate of the middle inlet is changed from 5.5 m/s to 5 m/s, and the total airflow velocity is decreased by 3%. The protocol here presents an optimization method simultaneously considering energy consumption and thermal performance of the battery management system that has been established, and it can be widely used to improve the life cycle of the battery pack with minimum operating cost.


Assuntos
Poeira , Material Particulado , Temperatura Alta , Lítio , Temperatura , Íons
3.
PLoS One ; 18(9): e0291024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37733705

RESUMO

BACKGROUND: Cell division cycle associated 2 (CDCA2), a member of the cell division cycle associated proteins (CDCA) family, is crucial in the regulation of cell mitosis and DNA repair. CDCA2 was extensively examined in our work to determine its role in a wide range of cancers. METHODS: CDCA2 differential expression was studied in pan-cancer and in diverse molecular and immunological subgroups in this research. Additionally, the diagnostic and prognostic significance of CDCA2 in pan-cancer was also evaluated using receiver operating characteristic (ROC) and Kaplan-Meier (KM) curves. Prognostic value of CDCA2 in distinct clinical subgroups of lower grade glioma (LGG) was also investigated and a nomogram was constructed. Lastly, potential mechanisms of action of CDCA2 were interrogated including biological functions, ceRNA networks, m6A modification and immune infiltration. RESULTS: CDCA2 is shown to be differentially expressed in a wide variety of cancers. Tumors are diagnosed and forecasted with a high degree of accuracy by CDCA2, and the quantity of expression CDCA2 is linked to the prognosis of many cancers. Additionally, the expression level of CDCA2 in various subgroups of LGG is also closely related to prognosis. The results of enrichment analyses reveal that CDCA2 is predominantly enriched in the cell cycle, mitosis, and DNA replication. Subsequently, hsa-miR-105-5p is predicted to target CDCA2. In addition, 4 lncRNAs were identified that may inhibit the hsa-miR-105-5p/CDCA2 axis in LGG. Meanwhile, CDCA2 expression is shown to be associated to m6A-related genes and levels of immune cell infiltration in LGG. CONCLUSION: CDCA2 can serve as a novel biomarker for the diagnosis and prognosis in pan-cancer, especially in LGG. For the development of novel targeted therapies in LGG, it may be a potential molecular target. However, to be sure, we'll need to do additional biological experiments to back up our results from bioinformatic predictions.


Assuntos
Glioma , MicroRNAs , Humanos , Prognóstico , Glioma/diagnóstico , Glioma/genética , Nomogramas , Ciclo Celular , Proteínas de Ciclo Celular/genética , Mitose/genética , Proteínas de Transporte , Proteínas Nucleares , MicroRNAs/genética
4.
J Vis Exp ; (196)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37358274

RESUMO

This study aims to solve the problems of air flow chaos and poor performance in a vented box caused by the heterogeneous distribution of airflow through the design of the internal structure of the vented box with constant energy consumption. The final goal is to evenly distribute the airflow inside the vented box. Sensitivity analysis was performed for three structural parameters: the number of pipes, the number of holes in the middle pipe, and the number of each increment from the inside to the outside pipe. A total of 16 random array sets of three structural parameters with four levels were determined using the orthogonal experimental design. Commercial software was used for the construction of a 3D model for the selected experimental points, and this data was used to obtain the airflow velocities, which were then used to obtain the standard deviation of each experimental point. According to the range analysis, the combination of the three structural parameters was optimized. In other words, an efficient and economical optimization method considering the performance of the vented box was established, and it could be widely used to extend the storage time of fresh food.

5.
ACS Omega ; 8(14): 13048-13058, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37065062

RESUMO

Thermal barrier coating (TBC) systems are widely adopted in gas turbine blades to improve the thermal efficiency of gas turbine engines. However, TBC failure will happen due to the thermal stress between the different layers of the TBC systems. The traditional two-layer theoretical model only considers TGO (thermally grown oxide) and a substrate in the inner cooling hole with the surface uncoated, which results in poor prediction of the deformations of the TBC systems. It should be mentioned that the effect of TBC is very important because the thickness of TBC is much larger than the TGO thickness. In this study, a new three-layer theoretical model was derived, which is composed of the cylindrical TGO and TBC mounted in the substrate with a circular hole, and the stress and strain of TGO near the cooling hole under the condition of the thermal cycles were calculated. The high temperature characteristics of TGO and the substrate including the high temperature strength and growth ratio were from the experiments. The results show that the strain of the developed three-layer model is irrelevant with increasing number of cycles, which indicates that TBC in the cooling hole significantly inhibits the deformation of TGO near the cooling hole. Therefore, aimed at confirming the feasibility of the three-layer theoretical model, the finite element analysis with coating in the cooling hole and on the surface was carried out with a three-layer axisymmetric model, which proves that the 3-layer theoretical model can predict the deformation trend near the cooling hole.

6.
Molecules ; 28(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677569

RESUMO

The electronic and magnetic properties of graphene/MoS2 heterostructures intercalated with 3d transition metal (TM) atoms at different concentrations have been systematically investigated by first principles calculations. The results showed that all the studied systems are thermodynamically stable with large binding energies of about 3.72 eV-6.86 eV. Interestingly, all the TM-intercalated graphene/MoS2 heterostructures are ferromagnetic and their total magnetic moments increase with TM concentration. Furthermore, TM concentration-dependent spin polarization is obtained for the graphene layer and MoS2 layer due to the charge transfer between TM atoms and the layers. A significant band gap is opened for graphene in these TM-intercalated graphene/MoS2 heterostructures (around 0.094 eV-0.37 eV). With the TM concentration increasing, the band gap of graphene is reduced due to the enhanced spin polarization of graphene. Our study suggests a research direction for the manipulation of the properties of 2D materials through control of the intercalation concentration of TM atoms.

7.
ACS Omega ; 8(2): 2291-2305, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36687020

RESUMO

To research the internal flow characteristics of a single-channel centrifugal pump, the computational fluid dynamics method is used in this study. Several monitoring points are set on the volute to analyze the change of pressure pulsation and radial force when the impeller rotates at different angles. The results show that the pressure pulsation in the single-channel pump volute is induced by the rotor-stator interaction and its harmonics. The monitoring points close to the separation tongue along the rotation direction of the impeller are more affected by the flow rate.

8.
ACS Omega ; 7(35): 31126-31137, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36092596

RESUMO

As a kind of green and sustainable technology, electric vehicles are continuously highlighted for solving the significant problems of energy and air pollution. In this paper, fault tolerance optimization of an air-cooled lithium battery pack having a damaged unit was considered to improve the heat dissipation performance. For constructing the relationship between the objective function and the design variables, a quadratic polynomial response function was set up based on the experimental points, which were selected by the Latin-hypercube design of experiment method. Then, a multi-island genetic algorithm-based optimization of the battery pack having a damaged unit was performed under the condition of adjusting the flow velocity of each inlet. The results show that the acceptable temperature differences were obtained under the condition of fixing the total mass flow rate of the inlets. The simulation and fault tolerance optimization methods recommended in this study can be widely used to improve the real safety level of the systems.

9.
ACS Omega ; 7(5): 4214-4223, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35155914

RESUMO

The effects of the design and optimization of trapezoidal channels and baffles on the net power density of proton-exchange membrane fuel cells (PEMFCs) are studied. The significant effects of the length of upper and lower sides of the trapezoidal cross section and the number and position of baffles on the net power density of PEMFC have been investigated. It is found that at the same flow rate, changing the effective contact surface between the flow channel and the gas diffusion layer can tremendously improve the current density of fuel cells; moreover, the performance of a PEMFC based on the addition of a baffle can be further improved. The results show that the trapezoidal cross-sectional flow channel with baffles has higher efficiency and better overall performance compared with a basic straight flow channel. In addition, the response surface was used to optimize the trapezoidal cross-sectional flow channel by considering the power loss of output power and the flow rate. The optimal result was obtained with an upper side length of 1.234 mm, a lower side length of 1.8 mm, and a baffle from the entrance at 9.5 mm, increasing the net power density by 4.347%.

10.
Aging (Albany NY) ; 13(5): 6890-6903, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33621951

RESUMO

BACKGROUND: Patients with non-small cell lung cancer (NSCLC) initially responding to tyrosine kinase inhibitors (TKIs) eventually develop resistance due to accumulating mutations in the EGFR and additional lesser investigated mechanisms such as the participation of the tumor microenvironment (TME). METHODS: Here, we examined the potential for MET inhibitor capmatinib for the treatment of osimertinib-resistant NSCLCs and normalizing the TME. RESULTS: We first established that HCC827 and H1975 cells showed increased resistance against osimertinib when co-cultured with CAFs isolated from osimertinib-resistant patients. Additionally, we showed that CAFs promoted epithelial-mesenchymal transition (EMT) and self-renewal ability in both HCC827 and H1975 cells. We subsequently found that both CAF-cultured HCC827 and H1975 showed a significantly higher expression of MET, Akt, Snail and IL-1ß, which were associated with survival and inflammatory responses. These cells in turn, promoted the generation of CAFs from normal lung fibroblasts. Subsequently, we observed that the treatment of capmatinib resulted in the re-sensitization of CAF-co-cultured H1975 and HCC827 to osimertinib, in association with reduced EMT and self-renewal ability. MET-silencing experiment using siRNA supported the observations made with capmatinib while with a greater magnitude. MET-silenced cell exhibited a severely hindered expression of inflammatory markers, IL-1ß and NF-κB; EMT markers, Snail and Vimentin, while increased E-cadherin. Finally, we demonstrated that the combination of capmatinib and osimertinib led to an increased tumor inhibition and significantly lower number of CAFs within the patient derived xenograft (PDX) model. CONCLUSION: Taken together, our findings suggested that an increased MET/Akt/Snail signaling was induced between the NSCLC cells and their TME (CAFs), resulting in osimertinib resistance. Suppression of this pathway by capmatinib may bypass the EGFR activating mutation and overcomes osimertinib resistance by targeting both tumor cells and CAFs.


Assuntos
Benzamidas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Imidazóis/farmacologia , Neoplasias Pulmonares/patologia , Transdução de Sinais/efeitos dos fármacos , Triazinas/farmacologia , Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Interleucina-1beta/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Fatores de Transcrição da Família Snail/metabolismo
11.
J Cell Physiol ; 236(8): 5953-5965, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33561315

RESUMO

Glioma is the most common type of primary brain tumor. Treatment options for recurrent gliomas include surgery, chemotherapy, and radiation therapy, but the clinical outcome is usually limited. In recent years, circular RNAs have been found to play a vital role in several human cancers. Gene Expression Omnibus database was utilized to verify the differentially expressed circRNAs. Then we detected that the expression of circular RNA circHECTD1 was significantly increased. The expression and function of circHECDT1 has not yet been reported in glioma. Then we confirmed that the level of circHECTD1 was significantly increased both in glioma tissues and cell lines, which is negatively correlated with the overall survival of patients. Knockdown of circHECTD1 inhibited proliferation and invasion in vitro, and also reduced the growth of tumor and prolonged the prognosis in vivo. Knockdown of circHECTD1 significantly elevated the miR-296-3p expression in LN229 and T98G cells. Luciferase reports and RNA immunoprecipitation data indicated that miR-296-3p was a direct target of circHECTD1 and that the miR-296-3p expression negatively regulated SLC10A7. Rescue experiments showed that the overexpression of SLC10A7 could impede the effects of circHECTD1 silencing on the proliferation and invasion of glioma cells. In this study, we identified that circHECTD1 regulates SLC10A7 by interacting with miR-296-3p in glioma cells. In conclusion, this study investigated a novel biomarker panel consisting of the circHECTD1/miR-296-3p/SLC10A7 axis, which is critical for glioma tumorigenesis and invasiveness and may represent a novel therapeutic target for intervening in glioma progression.


Assuntos
Glioma/patologia , MicroRNAs/genética , Recidiva Local de Neoplasia/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Simportadores/genética , Ubiquitina-Proteína Ligases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Carcinogênese/genética , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Humanos , Masculino , Pessoa de Meia-Idade , RNA Circular/genética , RNA Circular/metabolismo
12.
Small ; 16(41): e2002486, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32964603

RESUMO

Tin-based compounds have received much attention as anode materials for lithium/sodium ion batteries owing to their high theoretical capacity. However, the huge volume change usually leads to the pulverization of electrode, giving rise to a poor cycle performance, which have severely hampered their practical application. Herein, highly durable yolk-shell SnSe2 nanospheres (SnSe2 @SeC) are prepared by a multistep templating method, with an in situ gas-phase selenization of the SnO2 @C hollow nanospheres. During this process, Se can be doped into the carbon shell with a tunable amount and form SeC bonds. Density functional theory calculation results reveal that the SeC bonding can enhance the charge transfer properties as well as the binding interaction between the SnSe2 core and the carbon shell, favoring an improved rate performance and a superior cyclability. As expected, the sample delivers reversible capacities of 441 and 406 mAh g-1 after 2000 cycles at 2 and 5 A g-1 , respectively, as the anode material for a sodium-ion battery. Such performances are significantly better than the control sample without the SeC bonding and also other metal selenide-based anodes, evidently showing the advantage of Se doping in the carbon shell.

13.
Aging (Albany NY) ; 13(4): 4999-5019, 2020 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-33411683

RESUMO

Even after multimodal therapy, the prognosis is dismal for patients with brain metastases from non-small cell lung cancer (NSCLC). Although the blood-brain barrier (BBB) limits tumor cell penetration into the brain parenchyma, some nevertheless colonize brain tissue through mechanisms that are not fully clear. Here we show that homeobox B9 (HOXB9), which is commonly overexpressed in NSCLC, promotes epithelial-to-mesenchymal transition (EMT) and tumor migration and invasion. Animal experiments showed that HOXB9 expression correlates positively with the brain metastatic potential of human NSCLC cells, while brain metastatic cells derived through in vivo selection showed greater HOXB9 expression than their cells of origin. Comparable results were obtained after immunohistochemical analysis of clinical primary NSCLC and matched brain metastasis samples obtained after surgery. Using an in vitro BBB model, knockdown and overexpression experiments showed that HOXB9-dependent expression of MMP9 in NSCLC cells leads to reduced expression of junctional proteins in cultured human vascular endothelial cells and enhanced transmigration of tumor cells. These data indicate that HOXB9 enables NSCLC cells to break away from the primary tumor by inducing EMT, and promotes brain metastasis by driving MMP9 production and degradation of intercellular adhesion proteins in endothelial cells comprising the BBB.


Assuntos
Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Transição Epitelial-Mesenquimal/genética , Proteínas de Homeodomínio/genética , Neoplasias Pulmonares/genética , Células A549 , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Animais , Barreira Hematoencefálica/ultraestrutura , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/secundário , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Técnicas In Vitro , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Metaloproteinase 9 da Matriz/genética , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica , Transplante de Neoplasias , Proteínas de Junções Íntimas/metabolismo
14.
J Exp Clin Cancer Res ; 38(1): 380, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462285

RESUMO

BACKGROUND: Accumulating evidence demonstrates the oncogenic roles of lncRNA (long non-coding RNA) molecules in a wide variety of cancer types including glioma. Equally important, However, tumorigenic functions of lncRNA in glioma remain largely unclear. A recent study suggested lncRNA SNHG15 played a role for regulating angiogenesis in glioma but its role in the tumor microenvironment (TME) was not investigated. METHODS: First, we showed that SNHG15 was upregulated in GBM cells and associated with a poor prognosis for the patients of GBM using public databases. Next, we collected temozolomide sensitive (TMZ-S) and resistant (TMZ-R) clinical samples and demonstrated that co-culturing TMZ-R cells with HMC3 (microglial) cells promoted M2-polarization of HMC3 and the secretion of pro-GBM cytokines TGF-ß and IL-6. RESULTS: Comparative qPCR analysis of TMZ-S and TMZ-R cells showed that a significantly higher level of SNHG15, coincidental with a higher level of Sox2, ß-catenin, EGFR, and CDK6 in TMZ-R cells. Subsequently, using bioinformatics tool, a potential mechanistic route for SNHG15 to promote GBM tumorigenesis was by inhibiting tumor suppressor, miR-627-5p which leads to activation of CDK6. Gene-silencing technique was employed to demonstrate that suppression of SNHG15 indeed led to the suppression of GBM tumorigenesis, accompanied by an increase miR-627-5p and decreased its two oncogenic targets, CDK6 and SOX-2. In addition, SNHG15-silenced TMZ-R cells became significantly sensitive towards TMZ treatment and less capable of promoting M2-phenotype in the HMC3 microglial cells. We then evaluated the potential anti-GBM activity of CDK6 inhibitor, palbociclib, using TMZ-R PDX mouse models. Palbociclib treatment significantly reduced tumorigenesis in TMZ-R/HMC3 bearing mice and SNHG15 and CDK6 expression was significantly reduced while miR-627-5p level was increased. Additionally, palbociclib treatment appeared to overcome TMZ resistance as well as reduced M2 markers in HMC3 cells. CONCLUSION: Together, we provided evidence supporting the usage of CDK6 inhibitor for TMZ-resistant GBM cases. Further investigation is warranted for the consideration of clinical trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Piperazinas/farmacologia , Piridinas/farmacologia , RNA Longo não Codificante/metabolismo , Temozolomida/farmacologia , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos NOD , MicroRNAs/genética , MicroRNAs/metabolismo , Microglia/metabolismo , Microglia/patologia , Piperazinas/administração & dosagem , Piridinas/administração & dosagem , RNA Longo não Codificante/genética , Transdução de Sinais/efeitos dos fármacos , Temozolomida/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
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