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1.
J Transl Med ; 22(1): 547, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849954

RESUMO

BACKGROUND: Enhancers are important gene regulatory elements that promote the expression of critical genes in development and disease. Aberrant enhancer can modulate cancer risk and activate oncogenes that lead to the occurrence of various cancers. However, the underlying mechanism of most enhancers in cancer remains unclear. Here, we aim to explore the function and mechanism of a crucial enhancer in melanoma. METHODS: Multi-omics data were applied to identify an enhancer (enh17) involved in melanoma progression. To evaluate the function of enh17, CRISPR/Cas9 technology were applied to knockout enh17 in melanoma cell line A375. RNA-seq, ChIP-seq and Hi-C data analysis integrated with luciferase reporter assay were performed to identify the potential target gene of enh17. Functional experiments were conducted to further validate the function of the target gene ETV4. Multi-omics data integrated with CUT&Tag sequencing were performed to validate the binding profile of the inferred transcription factor STAT3. RESULTS: An enhancer, named enh17 here, was found to be aberrantly activated and involved in melanoma progression. CRISPR/Cas9-mediated deletion of enh17 inhibited cell proliferation, migration, and tumor growth of melanoma both in vitro and in vivo. Mechanistically, we identified ETV4 as a target gene regulated by enh17, and functional experiments further support ETV4 as a target gene that is involved in cancer-associated phenotypes. In addition, STAT3 acts as a transcription factor binding with enh17 to regulate the transcription of ETV4. CONCLUSIONS: Our findings revealed that enh17 plays an oncogenic role and promotes tumor progression in melanoma, and its transcriptional regulatory mechanisms were fully elucidated, which may open a promising window for melanoma prevention and treatment.


Assuntos
Proliferação de Células , Progressão da Doença , Elementos Facilitadores Genéticos , Regulação Neoplásica da Expressão Gênica , Melanoma , Humanos , Melanoma/genética , Melanoma/patologia , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos/genética , Proliferação de Células/genética , Movimento Celular/genética , Animais , Oncogenes/genética , Sistemas CRISPR-Cas/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Carcinogênese/genética , Carcinogênese/patologia , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Sequência de Bases , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética
2.
Materials (Basel) ; 17(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38591434

RESUMO

Measuring the size distribution and temperature of high-temperature dispersed particles, particularly in-flame soot, holds paramount importance across various industries. Laser-induced incandescence (LII) stands out as a potent non-contact diagnostic technology for in-flame soot, although its effectiveness is hindered by uncertainties associated with pre-determined thermal properties. To tackle this challenge, our study proposes a multi-parameter inversion strategy-simultaneous inversion of particle size distribution, thermal accommodation coefficient, and initial temperature of in-flame soot aggregates using time-resolved LII signals. Analyzing the responses of different heat transfer sub-models to temperature rise demonstrates the necessity of incorporating sublimation and thermionic emission for accurately reproducing LII signals of high-temperature dispersed particles. Consequently, we selected a particular LII model for the multi-parameter inversion strategy. Our research reveals that LII-based particle sizing is sensitive to biases in the initial temperature of particles (equivalent to the flame temperature), underscoring the need for the proposed multi-parameter inversion strategy. Numerical results obtained at two typical flame temperatures, 1100 K and 1700 K, illustrate that selecting an appropriate laser fluence enables the simultaneous inversion of particle size distribution, thermal accommodation coefficient, and initial particle temperatures of soot aggregates with high accuracy and confidence using the LII technique.

3.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 167015, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38182069

RESUMO

Enhancers, cis-acting DNA elements for transcriptional regulation, are important regulators of cell identity and disease. However, of the hundreds of thousands of enhancers annotated in the human genome, only a few have been studied for their regulatory mechanisms and functions in cancer progression and therapeutic resistance. Here, we report the pleiotropy of one enhancer (named enh9) in both cell proliferation and migration in non-small cell lung cancer (NSCLC) cells. By integrating multi-genomic data, ERMP1 and PD-L1 were screened out as potential targets of enh9. CUT&Tag sequencing demonstrated that enh9 was involved in the genomic interactions between the transcription factor RELA and the promoters of ERMP1 and PD-L1. In addition, ERMP1 and PD-L1 were validated to be involved in cell proliferation and migration, respectively. Our study fully elucidated the function and transcriptional regulation mechanisms of enh9 in NSCLC. The exploration on enhancers is promising to provide new insights for cancer diagnosis and therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Antígeno B7-H1/genética , Proliferação de Células/genética , Regiões Promotoras Genéticas
4.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38048082

RESUMO

With the development of sequencing technology and the dramatic drop in sequencing cost, the functions of noncoding genes are being characterized in a wide variety of fields (e.g. biomedicine). Enhancers are noncoding DNA elements with vital transcription regulation functions. Tens of thousands of enhancers have been identified in the human genome; however, the location, function, target genes and regulatory mechanisms of most enhancers have not been elucidated thus far. As high-throughput sequencing techniques have leapt forwards, omics approaches have been extensively employed in enhancer research. Multidimensional genomic data integration enables the full exploration of the data and provides novel perspectives for screening, identification and characterization of the function and regulatory mechanisms of unknown enhancers. However, multidimensional genomic data are still difficult to integrate genome wide due to complex varieties, massive amounts, high rarity, etc. To facilitate the appropriate methods for studying enhancers with high efficacy, we delineate the principles, data processing modes and progress of various omics approaches to study enhancers and summarize the applications of traditional machine learning and deep learning in multi-omics integration in the enhancer field. In addition, the challenges encountered during the integration of multiple omics data are addressed. Overall, this review provides a comprehensive foundation for enhancer analysis.


Assuntos
Genômica , Sequências Reguladoras de Ácido Nucleico , Humanos , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Aprendizado de Máquina
5.
Int J Mol Sci ; 24(18)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37762629

RESUMO

Bones are constantly exposed to mechanical forces from both muscles and Earth's gravity to maintain bone homeostasis by stimulating bone formation. Mechanotransduction transforms external mechanical signals such as force, fluid flow shear, and gravity into intracellular responses to achieve force adaptation. However, the underlying molecular mechanisms on the conversion from mechanical signals into bone formation has not been completely defined yet. In the present review, we provide a comprehensive and systematic description of the mechanotransduction signaling pathways induced by mechanical stimuli during osteogenesis and address the different layers of interconnections between different signaling pathways. Further exploration of mechanotransduction would benefit patients with osteoporosis, including the aging population and postmenopausal women.


Assuntos
Mecanotransdução Celular , Osteogênese , Humanos , Feminino , Idoso , Envelhecimento , Gravitação , Homeostase
6.
Mol Biol Rep ; 50(8): 6337-6347, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37310547

RESUMO

BACKGROUND: Degenerative disc disease(DDD)is one of the most important causes of low back pain (LBP). Programmed death of human nucleus pulposus mesenchymal stem cells (NPMSCs) plays an important role in the progression of DDD. Growth differentiation factor-5 (GDF-5) is a protein that promotes chondrogenic differentiation, and has been reported to slow the expression of inflammatory factors in nucleus pulposus cells. Compared with those in normal rats, MRI T2-weighted images show hypointense in the central nucleus pulposus region of the intervertebral disc in GDF-5 knockout rats. METHODS AND RESULTS: We aimed to evaluate the role of GDF-5 and Ras homolog family member A (RhoA) in NPMSCs. We used lipopolysaccharide (LPS) to simulate the inflammatory environment in degenerative disc disease, and performed related experiments on the effects of GDF-5 on NPMSCs, including the effects of pyroptosis, RhoA protein, and the expression of extracellular matrix components, and the effects of GDF-5, on NPMSCs. In addition, the effect of GDF-5 on chondroid differentiation of NPMSCs was included. The results showed that the addition of GDF-5 inhibited the LPS-induced pyroptosis of NPMSCs, and further analysis of its mechanism showed that this was achieved by activating the RhoA signaling pathway. CONCLUSION: These findings suggest that GDF-5 plays an important role in inhibiting the pyroptosis of NPMSCs and GDF-5 may have potential for degenerative disc disease gene-targeted therapy in the future.


Assuntos
Degeneração do Disco Intervertebral , Células-Tronco Mesenquimais , Núcleo Pulposo , Animais , Humanos , Ratos , Fator 5 de Diferenciação de Crescimento/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/terapia , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Núcleo Pulposo/metabolismo , Piroptose , Proteína rhoA de Ligação ao GTP/metabolismo , Transdução de Sinais
7.
Eur Spine J ; 32(10): 3561-3574, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37330937

RESUMO

PURPOSE: Adjacent segment degeneration (ASDeg) after anterior cervical discectomy and fusion (ACDF) seriously affects the long-term efficacy of the operation. Therefore, our team has done a lot of research on allograft intervertebral disc transplantation (AIDT) to prove its feasibility and safety. This study will compare the efficacy between AIDT and ACDF in the treatment of cervical spondylosis. METHODS: All patients who received ACDF or AIDT in our hospital from 2000 to 2016 and followed up for at least 5 years were recruited and divided into ACDF and AIDT groups. The clinical outcomes including functional scores and radiological data of both groups were collected and compared preoperatively and postoperatively at 1 week, 3 months, 6 months, 12 months, 24 months, 60 months and last follow-up. Functional scores included Japanese Orthopedic Association score (JOA), Neck Disability Index (NDI), Visual Analog Scale of Neck (N-VAS) and Arms (A-VAS) pain, the Short Form Health Survey-36 (SF-36) and imaging dates including digital radiographs in the lateral, hyperextension and flexion positions to assess the stability, sagittal balance and mobility of the cervical spine and magnetic resonance imaging (MRI) scans to assess the degeneration of adjacent segment. RESULTS: There were 68 patients with 25 in AIDT group and 43 in ACDF group. Satisfactory clinical results were obtained in both groups, but the long-term NDI score and N-VAS score in the AIDT group were better. The AIDT obtained the same stability and sagittal balance of the cervical spine as fusion surgery. The range of motion of adjacent segments can be restored to the preoperative level after transplantation, but this increases significantly after ACDF. There were significant differences in the superior adjacent segment range of motion (SROM) between two groups at 12 months (P = 0.039), 24 months (P = 0.035), 60 months (P = 0.039) and the last follow-up (P = 0.011). The inferior adjacent segment range of motion (IROM) and SROM had a similar trend in the two groups. The ratio value of the greyscale (RVG) of adjacent segments showed a downward trend. At the last follow-up, the RVG decreased more significantly in the ACDF group. At the last follow-up, there was a significant difference in the incidence of ASDeg between the two groups (P = 0.000). And the incidence of adjacent segment disease (ASDis) is 22.86% in the ACDF group. CONCLUSION: The allograft intervertebral disc transplantation may be as an alternative technique to traditional anterior cervical discectomy and fusion for the management of cervical degenerative diseases. For the more, the results showed it would improve cervical kinematics and reduce the incidence of adjacent segment degeneration.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Fusão Vertebral , Substituição Total de Disco , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/cirurgia , Degeneração do Disco Intervertebral/patologia , Seguimentos , Estudos Retrospectivos , Resultado do Tratamento , Disco Intervertebral/cirurgia , Discotomia/métodos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Vértebras Cervicais/patologia , Substituição Total de Disco/métodos , Aloenxertos/cirurgia , Fusão Vertebral/métodos
8.
Immun Inflamm Dis ; 11(5): e865, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37249300

RESUMO

BACKGROUND: Excessive oxidative stress has been accepted as one of the critical factors for intervertebral disc degeneration (IDD), which is associated with low back pain (LBP). Fisetin (Fis) is a bioactive flavonoid that possesses strong bioactive activity. In present study, we aimed to illuminate the role of Fis on nucleus pulposus mesenchymal stem cells (NPMSCs). METHODS: NPMSCs were isolated and cultured from rat NP tissues and identified by flow cytometry and multilinear differentiation. The cytotoxicity of Fis, EX-527, and hydrogen peroxide (H2 O2 ) on NPMSCs was validated using Cell Counting Kit-8 tests. Cell apoptosis was tested by flow cytometry and TUNEL assay. Inflammatory mediators were assessed by Elisa tests, RT-PCR. Extracellular matrix (ECM) metabolism was measured by Western blot analysis and RT-qPCR. The expression of the SIRT1 was evaluated by Western blot analysis. RESULTS: NPMSCs were successfully isolated and cultured from rat NP tissues, and it has been identified by flow cytometry and multilinear differentiation. The results showed that Fis attenuated H2 O2 -induced apoptosis, inflammation, and ECM degradation of NPMSCs. Moreover, the above protective effects of Fis can be inhibited by EX-527, a unique SIRT1 inhibitor, indicating that SIRT1 may involve in the mechanism of Fis in protecting NPMSCs from oxidative stress. CONCLUSIONS: As a natural compound with little cytotoxicity on NPMSCs, Fis alleviate H2 O2 -induced apoptosis, inflammation, and ECM degradation by suppressing oxidative stress, this finding may add the theoretical basis for research on new treatment of IDD based on NPMSCs.


Assuntos
Degeneração do Disco Intervertebral , Células-Tronco Mesenquimais , Núcleo Pulposo , Animais , Ratos , Degeneração do Disco Intervertebral/metabolismo , Núcleo Pulposo/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley , Sirtuína 1/genética , Sirtuína 1/metabolismo
9.
Angew Chem Int Ed Engl ; 62(10): e202216799, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602264

RESUMO

A simple, broad-scope rhodium(I)/chiral diene catalytic system for challenging asymmetric intramolecular cyclopropanation of various tri-substituted allylic diazoacetates was successfully developed. The low coordination state RhI -complex exhibits an extraordinarily high degree of tolerance to the variation in the extent of substitution of the allyl double bond, thus allowing the efficient construction of a wide range of penta-substituted, fused-ring cyclopropanes bearing three contiguous stereogenic centers, including two quaternary carbon stereocenters, in a highly enantioselective manner with ease at catalyst loading as low as 0.1 mol %. The stereoinduction mode of this RhI -carbene-directed asymmetric intramolecular cyclopropanation was investigated by DFT calculations, indicating that π-π stacking interactions between the aromatic rings of chiral diene ligand and diazo substrate play a key role in the control of the reaction enantioselectivity.

10.
Zhongguo Gu Shang ; 35(11): 1104-8, 2022 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-36415200

RESUMO

Anterior cervical discectomy and fusion (ACDF) has achieved good clinical results since it was used in clinic, and is considered as the gold standard for the treatment of cervical spondylosis. However, more and more attention has been paid to adjacent segment degeneration(ASDeg) after fusion, and the debate about its pathogenesis is mainly focused on the bio-machanical stress changes of adjacent segments caused by fusion and the result of the natural aging process. The occurrence of ASDeg after fusion seriously affect the med-and long-term outcome of surgery, and some patients even need secondary surgery. In order to reduce or even avoid the occurrence of ASDeg, many new techniques have emerged in clinic, such as artificial disc replacement with preservation of motor segments, emerging cell transplantation technology and so on, but the clinical effect still needs to be confirmed by a large number of studies. Therefore, finding the risk factors of ASDeg after fusion is of great significance for fusion surgery on the clinical work. At present, there is still no unified overview of the research on the risk factors of ASDeg. This article will review the research progress and corresponding countermeasures of the risk factors of ASDeg after ACDF, in order to guide the clinical application.


Assuntos
Espondilose , Substituição Total de Disco , Humanos , Fatores de Risco , Discotomia/efeitos adversos , Espondilose/cirurgia
11.
Behav Sci (Basel) ; 12(9)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36135148

RESUMO

How decisions are made when autonomous vehicles (AVs) are faced with moral dilemmas is still a challenge. For this problem, this paper proposed the concept of common principles, which were drawn from the general public choice and could be generally accepted by society. This study established five moral dilemma scenarios with variables including the number of sacrifices, passenger status, presence of children, decision-making power subjects, and laws. Based on existing questionnaire data, we used gray correlation analysis to analyze the influence of the individual and psychological factors of participants in decision-making. Then, an independent sample t-test and analysis of covariance were selected to analyze the influence relationship between individual and psychological factors. Finally, by induction statistics of decision choices and related parameters of participants, we obtain common principles of autonomous vehicles, including the principle of protecting law-abiding people, the principle of protecting the majority, and the principle of protecting children. The principles have different priorities in different scenarios and can meet the complex changes in moral dilemmas. This study can alleviate the contradiction between utilitarianism and deontology, the conflict between public needs and individualized needs, and it can provide a code of conduct for ethical decision-making in future autonomous vehicles.

12.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142404

RESUMO

Pyroptosis is a type of programmed cell death (PCD) accompanied by an inflammatory reaction and the rupture of a membrane. Pyroptosis is divided into a canonical pathway triggered by caspase-1, and a non-canonical pathway independent of caspase-1. More and more pyroptosis-related participants, pathways, and regulatory mechanisms have been exploited in recent years. Pyroptosis plays crucial roles in the initiation, progression, and metastasis of cancer and it affects the immunotherapeutic outcome by influencing immune cell infiltration as well. Extensive studies are required to elucidate the molecular mechanisms between pyroptosis and cancer. In this review, we introduce the discovery history of pyroptosis, delineate the signaling pathways of pyroptosis, and then make comparisons between pyroptosis and other types of PCD. Finally, we provide an overview of pyroptosis in different cancer types. With the progression in the field of pyroptosis, new therapeutic targets and strategies can be explored to combat cancer.


Assuntos
Neoplasias , Piroptose , Apoptose , Caspase 1/metabolismo , Humanos , Proteínas de Neoplasias/metabolismo , Neoplasias/patologia
13.
Yi Chuan ; 44(4): 275-288, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35437236

RESUMO

Enhancer is a DNA sequence, and mainly acts in cis to regulate gene transcription. Due to the uncertainty in both location and distance between enhancers and their target genes, it is more complex and difficult to study the underlying regulatory mechanism of enhancers. Accumulating evidences indicate that enhancers are closely associated with the occurrence and development of diseases, such as cancer. Therefore, the studies of enhancers in cancer will be helpful to deeply unravel cancer pathogenesis and to promote the development of antitumor drugs. The related research is with great social significance and economic value. Currently, the identification of enhancers is insufficient. The regulatory mechanisms by enhancers during the initiation and progression of cancer and other diseases have not been fully delineated. In this review, we provide an overview of enhancers, super enhancers and their properties, followed by a description of enhancer prediction and identification at the genome-wide level. Finally, we summarize the regulatory roles of enhancers during diseases such as cancer in recent years, thereby providing a reference for the future exploration on enhancer regulatory mechanisms as well as cancer diagnosis and treatment.


Assuntos
Elementos Facilitadores Genéticos , Neoplasias , Humanos , Neoplasias/genética
14.
Membranes (Basel) ; 12(4)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35448394

RESUMO

Hollow fiber membranes were produced from a commercial polyvinylidene fluoride (PVDF) polymer, Kynar HSV 900, with a unique sandwich structure consisting of two sponge-like layers connected to the outer and inner skin layers while the middle layer comprises macrovoids. The sponge-like layer allows the membrane to have good mechanical strength even at low skin thickness and favors water vapor transportation during vacuum membrane distillation (VMD). The middle layer with macrovoids helps to significantly reduce the trans-membrane resistance during water vapor transportation from the feed side to the permeate side. Together, these novel structural characteristics are expected to render the PVDF hollow fiber membranes more efficient in terms of vapor flux as well as mechanical integrity. Using the chemistry and process conditions adopted from previous work, we were able to scale up the membrane fabrication from a laboratory scale of 1.5 kg to a manufacturing scale of 50 kg with consistent membrane performance. The produced PVDF membrane, with a liquid entry pressure (LEPw) of >3 bar and a pure water flux of >30 L/m2·hr (LMH) under VMD conditions at 70−80 °C, is perfectly suitable for next-generation high-efficiency membranes for desalination and industrial wastewater applications. The technology translation efforts, including membrane and module scale-up as well as the preliminary pilot-scale validation study, are discussed in detail in this paper.

15.
Cancers (Basel) ; 14(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35008400

RESUMO

Pyroptosis is a newly characterized type of programmed cell death. However, its function in cancer progression and its response to treatments remain controversial. Here, we extensively and systematically compiled genes associated with pyroptosis, integrated multiomics data and clinical data across 31 cancer types from The Cancer Genome Atlas, and delineated the global alterations in PRGs at the transcriptional level. The underlying transcriptional regulations by copy number variation, miRNAs, and enhancers were elucidated by integrating data from the Genotype-Tissue Expression and International Cancer Genome Consortium. A prognostic risk model, based on the expression of PRGs across 31 cancer types, was constructed. To investigate the role of pyroptosis in immunotherapy, we found five PRGs associated with effectiveness by exploring the RNA-Seq data of patients with immunotherapy, and further identified two small-molecule compounds that are potentially beneficial for immunotherapy. For the first time, from a pyroptosis standpoint, this study establishes a novel strategy to predict cancer patient survival and immunotherapeutic outcomes.

16.
Opt Express ; 28(25): 37249-37264, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33379563

RESUMO

For the ill-posed inverse problem of LII-based nanoparticle size measurement, recovered primary particle size distribution (PPSD) is sensitive to the uncertainty of LII model parameters. In the absence of reliable prior knowledge, the thermal accommodation coefficient (TAC) and fractal-dependent shielding factor are often required to be inferred simultaneously with the PPSD. In the simplified LII model for low fluence regime, TAC and fractal-dependent shielding factor are combined to define a new fractal-dependent TAC. The present study theoretically verified the feasibility of inferring PPSD and fractal-dependent TAC from the normalized LII signals. Moreover, the inversion is independent of prior knowledge of most full LII model parameters, which is attributed to low laser fluence, normalized signal, and fractal-dependent TAC.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31936406

RESUMO

This study investigated the relationship between personality states and driving behavior from a dynamic perspective. A personality baseline was introduced to reflect the driver's trait level and can be used as a basic reference for the dynamic change of personality states. Three kinds of simulated scenarios triggered by pedestrian crossing the street were established using a virtual reality driving simulator. Fifty licensed drivers completed the driving experiments and filled in the Neuroticism Extraversion Openness Five-Factor Inventory (NEO-FFI) questionnaire to measure the drivers' personality baselines. Key indicators were quantified to characterize the five types of personality states by K-means clustering algorithm. The results indicated that the high-risk situation had a greater impact on the drivers, especially for drivers with openness and extroversion. Furthermore, for the drivers of extroverted personality, the fluctuation of personality states in the high-risk scenario was more pronounced. This paper put forward a novel idea for the analysis of driving behavior, and the research results provide a personalized personality database for the selection of different driving modes.


Assuntos
Condução de Veículo , Personalidade , Adulto , Feminino , Humanos , Licenciamento , Masculino , Pessoa de Meia-Idade , Pedestres , Assunção de Riscos , Inquéritos e Questionários , Realidade Virtual
18.
Angew Chem Int Ed Engl ; 58(16): 5422-5426, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30860302

RESUMO

Over the past years, the metal-catalyzed dearomative cycloaddition of 3-nitroindoles and 2-nitrobenzofurans have emerged as a powerful protocol to construct chiral fused heterocyclic rings. However, organocatalytic dearomative reaction of these two classes of heteroarenes has become a long-standing challenging task. Herein, we report the first example of phosphine-catalyzed asymmetric dearomative [3+2]-cycloadditio of 3-nitroindoles and 2-nitrobenzofurans, which provide a new, facile, and efficient protocol for the synthesis of chiral 2,3-fused cyclopentannulated indolines and dihydrobenzofurans by reacting with allenoates and MBH carbonates, respectively through a dearomative [3+2]-cycloaddition.

19.
Opt Express ; 27(2): 1613-1631, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696225

RESUMO

A new technique is developed to retrieve the fractal dimension and size distribution of soot aggregates simultaneously from the relative intensities of multi-wavelength angular-resolved light scattering. Compared with other techniques, the main advantage of this method is its independence of knowing complex refractive index, number density of aggregate, fractal prefactor and primary particle diameter. The forward light scattering procedure of soot aggregate is described by Rayleigh-Debye-Gans polydisperse fractal aggregate (RDG-PFA) scattering theory, and the retrieval process is performed by using the covariance matrix adaption-evolution strategy algorithm (CMA-ES). Three different measurement models, i.e. absolute scattering and transmittance, absolute scattering, relative scattering (RS), are investigated in present research. Numerical experiments have been performed to test the feasibility of the CMA-ES algorithm. Combined with the multi-wavelength RDG-PFA strategy, the retrieval accuracy of soot aggregate size distribution is proved to be more effectively by using the RS model. Satisfactory results under 10% Gaussian measurement noise have demonstrated the feasibility of the proposed method.

20.
Org Lett ; 19(22): 6080-6083, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-29077416

RESUMO

The first enantioenriched synthesis of 1,1,3-trisubstituted (trifluoromethyl)indene derivatives, bearing a quaternary stereogenic carbon center, is reported using a simple chiral sulfinamide phosphine-catalyzed asymmetric allylic alkylation of a mixture of indenes with Morita-Baylis-Hillman carbonates. The resulting derivatives can serve as a valuable synthetic building block for some drugs and natural products. Broad substrate scope and high regio- and enantioselectivity of this reaction were particularly remarkable.

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