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1.
J Chem Phys ; 159(11)2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37721329

ABSTRACT

The formation of angulon, stemming from the rotor (molecule or impurity), rotating in the quantum many-body field, adds a new member to the quasi-particles' family and has aroused intense interest in multiple research fields. However, the analysis of the coupling strength between the rotor and its hosting environment remains a challenging task, both in theory and experiment. Here, we develop the all-coupling theory of the angulon by introducing a unitary transformation, where the renormalization of the rotational constants for different molecules in the helium nanodroplets is reproduced, getting excellent agreement with the experimental data collected during the past decades. Moreover, the strength of molecule-helium coupling and the effective radius of the solvation shell co-rotating along with the molecular rotor could be estimated qualitatively. This model not only provides significant enlightenment for analyzing the rotational spectroscopy of molecules in the phononic environment, but also provides a new method to study the transfer of the phonon angular momentum in the angulon frame.

2.
Cancer Sci ; 114(7): 2739-2749, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37010195

ABSTRACT

Tumor angiogenesis plays an important role in the development of cancer as it allows the delivery of oxygen, nutrients, and growth factors as well as tumor dissemination to distant organs. Although anti-angiogenic therapy (AAT) has been approved for treating various advanced cancers, this potential strategy has limited efficacy due to resistance over time. Therefore, there is a critical need to understand how resistance develops. Extracellular vesicles (EVs) are nano-sized membrane-bound phospholipid vesicles produced by cells. A growing body of evidence suggests that tumor cell-derived EVs (T-EVs) directly transfer their cargoes to endothelial cells (ECs) to promote tumor angiogenesis. Importantly, recent studies have reported that T-EVs may play a major role in the development of resistance to AAT. Moreover, studies have demonstrated the role of EVs from non-tumor cells in angiogenesis, although the mechanisms involved are still not completely understood. In this review, we provide a comprehensive description of the role of EVs derived from various cells, including tumor cells and non-tumor cells, in tumor angiogenesis. Moreover, from the perspective of EVs, this review summarized the role of EVs in the resistance to AAT and the mechanisms involved. Due to their role in the resistance of AAT, we here proposed potential strategies to further improve the efficacy of AAT by inhibiting T-EVs.


Subject(s)
Endothelial Cells , Extracellular Vesicles , Humans , Endothelial Cells/metabolism , Neovascularization, Pathologic/pathology , Extracellular Vesicles/metabolism , Cell Communication
3.
J Phys Condens Matter ; 35(12)2023 Jan 31.
Article in English | MEDLINE | ID: mdl-36657176

ABSTRACT

The systematical analysis for varieties of defects with different depths and lattice relaxation strengths in metal halide perovskites (MHPs) is a challenging task. Here, we study the energy shifts of the full-configuration defects due to the polaron effect based on the all-coupling variational method in MHPs, where these polaron states are formed stemming from different defect species coupling with the longitudinal optical phonon modes via Fro¨hlich mechanism. We find that the polaron effect results in defect levels varying from tens to several hundreds of meV, which are very close to the correction of defect levels due to the defect-polaron effect, especially for these defects migration proved in the recent experiments in MHPs. These results provide the significant enlightenment not only for analyzing the radiation and non-radiation processes of carriers mediated by defects, but also for optimizing defect effect in the photovoltaic and photoelectric devices based on MHPs materials.

4.
Oral Dis ; 29(4): 1542-1549, 2023 May.
Article in English | MEDLINE | ID: mdl-35247026

ABSTRACT

OBJECTIVES: Depth of invasion (DOI) is the most important predictor for lymph node metastasis in early-stage oral cancer. This study aims to investigate the effects of the different classifications of AJCC 7th and 8th on predicting lymph node metastasis and the optimal cutoff point for DOI predicting the lymph node metastasis in patients with tongue squamous cell carcinoma (TSCC). MATERIALS AND METHODS: We performed a retrospective study in 208 TSCC patients in early T stage without clinical or radiological signs of lymph node metastasis. Those patients were treated with elective neck dissection (END) between April 2019 and December 2020. And the relation between DOI and lymph node metastasis was analyzed. RESULTS: Metastases were found in 58 of 208 patients (27.88%). Of those 58 patients, the mean DOI was 8.311 mm compared to 5.425 mm in patients without metastases (p < 0.0001). The receiver operating characteristic curve (ROC curve) showed an area under the curve of 0.7066 with the most optimal cutoff point on a DOI of 4.050 mm (sensitivity 86.21%, specificity 52%). Linear regression analysis (1 mm ≤ DOI ≤6 mm) revealed that a DOI ≥ 3.211 mm predicated an incidence of occult lymph node metastasis greater than 20%. Regional metastases were found in 12.82% of patients with DOI ≤ 4.0 mm. Within the entire cohort, 60 cases (28.85%) got upgraded with respect to T stage. No tumor underwent downstaging. CONCLUSION: The 8th edition provides better lymph node metastasis prediction for TSCC than the 7th. And DOI is a poor predictor for regional metastasis in patients with early T stage clinically node-negative TSCC. END in patients with early-stage TSCC should be performed in patients with DOI ≥ 3.211 mm.


Subject(s)
Carcinoma, Squamous Cell , Tongue Neoplasms , Humans , Carcinoma, Squamous Cell/pathology , Tongue Neoplasms/surgery , Tongue Neoplasms/pathology , Lymphatic Metastasis/pathology , Retrospective Studies , Neoplasm Staging , Tongue , Prognosis , Lymph Nodes/pathology
5.
J Phys Chem Lett ; 13(38): 8858-8863, 2022 Sep 29.
Article in English | MEDLINE | ID: mdl-36123602

ABSTRACT

Metal halide perovskites quantum dots (MHPQDs) have aroused enormous interest in the photovoltaic and photoelectric disciplines because of their marvelous properties and size characteristics. However, one of the key problems of how to systematically analyze charge carriers trapped by defects is still a challenging task. Here, we study multiphonon processes of the charge carrier trapping by various defects in MHPQDs based on the well-known Huang-Rhys model, in which a method of a full-configuration defect, including different defect species with variable depth and lattice relaxation strength, is developed by introducing a localization parameter in the quantum defect model. With the help of this method, these fast trapping channels for charge carriers transferring from the quantum dot ground state to different defects are found. Furthermore, the dependence of the trapping time on the radius of quantum dot, the defect depth, and temperature is given. These results not only enrich the knowledge of charge carrier trapping processes by defects, but also bring light to the designs of MHPQDs-based photovoltaic and photoelectric devices.

6.
Huan Jing Ke Xue ; 43(7): 3523-3531, 2022 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-35791536

ABSTRACT

In order to propose pertinent suggestions regarding eutrophication control for Lake Hongze, we used monthly monitoring data from 2011 to 2020 to elucidate the spatiotemporal changing characteristics of eutrophic status and the relevant driving factors. As the main river entering Lake Hongze, River Huaihe experienced an increase in permanganate index and a decrease in TN in the last 10 years. Meanwhile, Secchi depth, TP, and permanganate index increased, whereas TN and Chl-a concentration decreased significantly in Lake Hongze. As a result, the eutrophic status TLI index of Lake Hongze declined over the past 10 years. The change trend of TLI in Lake Hongze differed spatially. As the main water passage of River Huaihe, the algal biomass was lower in the eastern region than that in the other two lake regions, regardless of the relatively high nutrient concentration, due to the short water retention time. Furthermore, the water quality of River Huaihe improved; thus, the TLI index decreased significantly in the eastern lake region. The northern region had a high coverage of aquatic vegetation, which not only reduced the concentration of water nutrients but also provided a habitat for zooplankton and fish, effectively inhibiting algal growth. Thus, the TLI index was lowest among the three lake areas and showed a downward trend over the last 10 years. In the western region, the algal biomass was the highest due to the intensification of phosphorus release from sediment in summer. Thus, the TLI index was the highest and had not improved in the past 10 years. There were also significant seasonal differences in the TLI of Lake Hongze, which was highest in summer, due to the relatively high algal biomass. Moreover, the algal biomass in summer was mainly affected by the concentration of nitrate. According to the spatiotemporal distribution characteristics of eutrophic status and the impacting factors in Lake Hongze, corresponding measures for eutrophication control should be taken for different seasons and lake areas.


Subject(s)
Environmental Monitoring , Eutrophication , Animals , Lakes , Phosphorus/analysis , Rivers
7.
J Hazard Mater ; 435: 128959, 2022 08 05.
Article in English | MEDLINE | ID: mdl-35483265

ABSTRACT

In situ leaching of ion-adsorption rare earth element (REE) deposits has released large amounts of REE-containing wastewater. However, the origin, speciation, distribution and migration of REEs in aqueous systems of the mining catchment are poorly understood. Groundwater, surface water, in situ leachates and weathered granite soil samples were collected from a catchment affected by mining activities in South China. The REE concentrations in groundwater (6.18 × 10-3-0.49 µmol L-1) and surface water (2.54-44.05 µmol L-1) decreased from upstream to downstream. REEs in groundwater were detected in organic matter associated (FA-REE) colloids, while the REE3+ and REE(SO4)+ were converted to REE(CO3)+ and FA-REE colloids from leachates and upstream surface water to downstream. The REE patterns of leachates and upstream groundwater (light and middle REE enrichment) resembled those of soil, but showed heavy REE enrichment due to FA-REE colloids in the downstream. REE in surface water were derived from middle REE enriched leachate. The Ce and Eu anomalies in the water samples indicated the REE origin (i.e., mining activities) and the hydrological variations (e.g., oxidation environment and water-rock interaction). Our results reveal the origin and fate of REE in aqueous systems of ion-adsorption REE mining catchments.


Subject(s)
Environmental Monitoring , Metals, Rare Earth , China , Environmental Monitoring/methods , Mining , Soil , Water
8.
J Phys Chem Lett ; 13(16): 3732-3739, 2022 Apr 28.
Article in English | MEDLINE | ID: mdl-35445599

ABSTRACT

The self-trapped state (STS) of the interlayer exciton (IX) has aroused enormous interest owing to its significant impact on the fundamental properties of the van der Waals heterostructures (vdWHs). Nevertheless, the microscopic mechanisms of STS are still controversial. Herein, we study the corrections of the binding energies of the IXs stemming from the exciton-interface optical phonon coupling in four kinds of vdWHs and find that these IXs are in the STS for the appropriate ratio of the electron and hole effective masses. We show that these self-trapped IXs could be classified into type I with the increasing binding energy in the tens of millielectronvolts range, which are very agreement with the red-shift of the IX spectra in experiments, and type II with the decreasing binding energy, which provides a possible explanation for the blue-shift and broad line width of the IX's spectra at low temperatures. Moreover, these two types of exciton states could be transformed into each other by adjusting the structural parameters of vdWHs. These results not only provide an in-depth understanding for the self-trapped mechanism but also shed light on the modulations of IXs in vdWHs.

9.
Phys Chem Chem Phys ; 24(8): 5048-5051, 2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35144279

ABSTRACT

Inelastic electron transfer, regarded as one of the potential mechanisms to explain odorant recognition in atomic-scale processes, is still a matter of intense debate. Here, we study multiphonon processes of electron transfer using the Markvart model and calculate their lifetimes with the values of key parameters widely adopted in olfactory systems. We find that these multiphonon processes are as quick as the single phonon process, which suggests that contributions from different phonon modes of an odorant molecule should be included for electron transfer in olfaction. Meanwhile, the temperature dependence of electron transfer could be analyzed effectively based on the reorganization energy which is expanded into the linewidth of multiphonon processes. Our theoretical results not only enrich the knowledge of the mechanism of olfaction recognition, but also provide insights into quantum processes in biological systems.


Subject(s)
Electrons , Smell , Electron Transport , Odorants , Temperature
10.
J Phys Chem Lett ; 12(45): 11182-11190, 2021 Nov 18.
Article in English | MEDLINE | ID: mdl-34761944

ABSTRACT

Quantum defects have been shown to play an essential role in nonradiative recombination in metal halide perovskites (MHPs). Nonetheless, the processes of charge transfer assisted by defects are still ambiguous. Herein, we theoretically study the nonradiative multiphonon processes among different types of quantum defects in MHPs using Markvart's model for the induced mechanisms of electron-electron and electron-phonon interactions. We find that the charge carrier can transfer between the neighboring levels of the same type of shallow defects by multiphonon processes, but it will be distinctly suppressed with an increase in the defect depth. For the nonradiation multiphonon transitions between donor- and acceptor-like defects, the processes are very fast and not sensitive to the defect depth, which provides a possible explanation for the phenomenon of blinking of photoluminescence spectra. We also discuss the temperature dependence of these multiphonon processes and find that their variational trends depend on the comparison of the Huang-Rhys factor with the emitted phonon number. These theoretical results not only fill some of the gaps in defect-assisted nonradiative processes in the perovskite materials but also provide deeper physical insights into producing higher-performance perovskite-based devices.

11.
Org Lett ; 23(15): 5719-5723, 2021 08 06.
Article in English | MEDLINE | ID: mdl-34286981

ABSTRACT

A rhodium(III)-catalyzed C-H allylation of (hetero)arenes by using 2-methylidenetrimethylene carbonate as an efficient allylic source has been developed for the first time. Five different directing groups including oxime, N-nitroso, purine, pyridine, and pyrimidine were compatible, delivering various branched allylarenes bearing an allylic hydroxyl group in moderate to excellent yields.

13.
J Phys Condens Matter ; 33(23)2021 May 13.
Article in English | MEDLINE | ID: mdl-33827068

ABSTRACT

We propose a theoretical model for studying the effective velocities of polaron spin states in monolayer transition metal dichalcogenides (TMDS) on the substrate. It is found that the effective velocity of polaron shows the splitting with different magnitudes due to the Rashba spin-orbit coupling, which results in the reversed distribution of the effective velocities of polaron spin states. Moreover, the reversed points depend on the truncated wave-vector of optical phonon and can be modulated by the polarity of substrate and the internal distance between monolayer TMDS and substrate. These theoretical results enlighten some simple ways to distinguish and modulate the polaron spin states in two-dimensional heterostructures.

14.
J Phys Condens Matter ; 33(14)2021 Feb 16.
Article in English | MEDLINE | ID: mdl-33494077

ABSTRACT

Quantum defects are essential to understand the non-radiative recombination processes in metal halide perovskites-based photovoltaic devices, in which Huang-Rhys factor, reflecting the coupling strength between the charge carrier and optical phonons, plays a key role in determining the non-radiative recombination via multiphonon processes. Herein, we theoretically present multiphonon Raman scattering intermediated by defects arising from the charge carrier of defect coupled with the longitudinal optical (LO) phonon in the deformation potential and Fröhlich mechanisms, respectively. We find that the Raman scattering shows multiple LO phonon overtones at equal interval LO phonons, where Huang-Rhys factor could be evaluated by the order of the strongest overtone. Meanwhile, we give the combinational multiphonon scattering between two mechanisms. Different types of the combinational modes with the weak scattering intensities provide a possible explanation for the long non-radiative charges-carrier lifetimes in metal halide perovskites.

15.
Acta Anatomica Sinica ; (6): 803-811, 2021.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1015418

ABSTRACT

Objective To explore the regional differences of body anthropometric traits in the Han population. Methods From 2015 to 2019, thirty-one body anthropometric traits of three Han ethnic groups were measured from Nanning (Guangxi), Zhengzhou (He'nan), and Taizhou (Jiangsu). The gender and regional difference analysis of each trait, and the correlation analysis between age and traits were carried out. Based on the principal component analysis of individual data of body phenotypic traits, the traits with significant regional difference were extracted to finely describe the physical characteristics of the Han peoplpe in the three regions. Results Most of the anthropometric traits of the three Han populations were statistically different in gender and region, and there was a positive or negative correlation between certain traits and age. The result of principal component analysis based on individual data showed that there were obvious regional differences in body anthropometric traits of the Han people. The difference between the Han Chinese in Guangxi ( south of the Yangtze River ) with He ' nan ( north of the Huaihe River ) and Jiangsu was relatively large, and difference was relatively small between He ' nan and Jiangsu Han Chinese. Meanwhile the Han Chinese in Jiangsu had its own characteristics in part of the phenotypic traits, which could be distinguished from the Han Chinese in He ' nan. Conclusion The research on the body anthropometric traits confirmed that there were significant regional differences in Han population, and suggested that the Yangtze River might be the largest geographic barrier for the population migration and genetic exchange between the north and south population.

16.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-921927

ABSTRACT

OBJECTIVE@#To evaluate the effect of one-stage treatment of bone morphogenetic protein 2 combined with Jifusheng in the experimental model of osteomyelitis in rabbits.@*METHODS@#The model of chronic osteomyelitis of tibia was established in 30 3-month-old male New Zealand white rabbits with a body weight of (2.0±0.5) kg, and the model was verified 4 weeks after operation. Thirty rabbits with osteomyelitis were randomly divided into 3 groups with 10 rabbits in each group (@*RESULTS@#At 4 weeks after operation, 30 rabbits with osteomyelitis were successfully validated. The results of serological examination showed that the hypersensitive C-reactive protein (CRP) and white blood cell count(WBC)in the model group were significantly higher than those in the blank group at 2 and 4 weeks after operation. Eight weeks after treatment, the detection of blood indexes showed that the white blood cell count (WBC)and hypersensitive C reactive protein (CRP)in treatment group A and treatment group B were significantly lower than those in the model group (@*CONCLUSION@#The combined application of apolipoprotein 2-Jifusheng can promote bone repair and reduce the inflammation of the focus. it can treat rabbits with osteomyelitis in one stage, provide objective basis for the formulation of clinical treatment strategy of osteomyelitis and further promote clinical research.


Subject(s)
Animals , Male , Rabbits , Apolipoproteins , Bone Density , Bone and Bones , Osteomyelitis/drug therapy , Tibia
17.
Article in English | WPRIM (Western Pacific) | ID: wpr-922777

ABSTRACT

An eco-friendly and fast HPLC method was developed for the determination of adenosine, inosine, guanosine and uridine in Cordyceps and related products (fermented mycelia of Hirsutella sinensis andPaecilomyces hepiali). The sample was ultrasonically extracted using 0.5% phosphoric acid solutions for 2.5 min. Sample separation was performed on a Poroshell SB-Aq column (50 mm × 4.6 mm, 2.7 μm) using eco-friendly mobile phase consisting of formic acid and ammonium formate aqueous solution at a flow rate of 1.0 mL·min


Subject(s)
Adenosine , Chromatography, High Pressure Liquid , Cordyceps , Nucleosides
18.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-879088

ABSTRACT

Alzheimer's disease(AD) is a chronic progressive neurodegenerative disease with recent memory impairment as the main clinical manifestation and senile plaques and neurofibrillary tangles as the main pathological changes. In recent years, the effect of microRNAs on AD has attracted widespread attention. Patients with AD have abnormal expression of miRNA, which is closed related to regulation of AD pathophysiology-related genes. Therefore, this paper first elaborated neuroprotective and toxic effects of microRNA in AD, and then explored relevant traditional Chinese medicines that can regulate miRNA in the treatment of AD, so as to provide basis for revealing the pathogenesis relationship between miRNA and AD and provide ideas for further development of anti-AD traditional Chinese medicine.


Subject(s)
Humans , Alzheimer Disease/genetics , Medicine, Chinese Traditional , MicroRNAs/genetics , Neurodegenerative Diseases
19.
Acta Pharmaceutica Sinica ; (12): 1057-1062, 2021.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-886972

ABSTRACT

This study investigated the effects of ginkgolide B on the long-chain fatty acid metabolism-related enzyme protein peroxisome proliferators-activated receptors α (PPARα), long-chain specific acyl-CoA dehydrogenase (LCAD), carnitine palmitoyl transterase-1 (CPT-1), and acyl coenzyme A oxidase 1 (ACOX1) expression in the liver of rats with non-alcoholic fatty liver disease (NAFLD). All the animal welfare and experimental procedures are in accordance with the regulations of the Animal Ethics Committee of Yunnan University of Traditional Chinese Medicine. After successfully building the rat model of non-alcoholic abnormal liver disease, the rats were divided into the model group, the simvastatin group, and the low-dose, middle-dose, and high-dose groups of ginkgolide B according to random number method, and were given corresponding drug treatment 4 weeks. We detected liver pathological indicators and determined blood lipids, transaminase and anti-oxidation indexes. Western blot and RT-PCR assays were used to detect the protein and mRNA levels of PPARα, LCAD, CPT-1, and ACOX1 in livers. The results showed that: ① the liver histopathology showed that the liver slices of the model group had obvious structural disorder, the nucleus was squeezed, and there were obvious fat vacuoles. The treatment groups improved significantly compared with the model group; ② compared with the normal group, the liver function and blood lipid indexes of the model group increased significantly, while the anti-oxidation indexes decreased significantly. Compared with the model group, each treatment groups were significantly improved; ③ compared with the normal group, the protein and mRNA expression levels of PPARα, ACOX1, CPT-1, and LCAD in the model group were significantly reduced, compared with the model group, those indexes in the treatment groups were significantly up-regulated. This study found that ginkgolide B could regulate the expression of long-chain fatty acid metabolism-related proteins PPARα, ACOX1, CPT-1, and LCAD, meanwhile improve the body's antioxidant capacity, thereby reduce blood lipids, further improve liver function and protect the liver.

20.
J Phys Condens Matter ; 32(42): 425005, 2020 Jul 03.
Article in English | MEDLINE | ID: mdl-32619995

ABSTRACT

We study the infrared optical absorption of magnetopolaron resonance states in graphene in the strong magnetic field based on the Huybrechts's model, in which polaron states are formed due to the strong coupling between electrons and surface optical (SO) phonons induced by the polar substrate. We propose the special magnetopolaron states [Formula: see text], namely, the superposition states between one SO phonon and the first-excited Landau level, which split into two branches of coupling modes and give rise to two optical absorption peaks with different intensities. Moreover, their intensities can be sensitively modulated by the magnetic field, the truncated wave-vector of SO phonon, polarity of substrate and internal distance between graphene and substrate. These results indicate that the structure of graphene laying on the polar substrate provide a good platform for exploring the polaron resonance states and magneto-optical transitions by infrared spectroscopy.

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