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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(2): 121-127, 2023 Feb 12.
Artículo en Chino | MEDLINE | ID: mdl-36740371

RESUMEN

Objective: To evaluate the influencing factors of poor treatment adherence in patients with uncontrolled asthma in China. Methods: From April 2017 to April 2018, all asthma patients with uncontrolled asthma and poor compliance in 32 third-class hospitals in 28 provinces and cities of China mainland included in the "National Mobile Asthma Assessment and Management Project" were selected as the subjects. A total of 923 patients were enrolled in the study including 388 males and 535 females. By analyzing the baseline data of the patients at the initial visit when enrolled, the influencing factors of poor adherence of adult asthma was analyzed by inter-group comparison and χ2 test. Results: Poor compliance in asthma was related to the following factors: age from 59 to 68 years old, course of disease more than 20 years, low education level, non-local follow-up, having obstructive ventilation dysfunction and low awareness of the disease[P values were 0.026(t=1.20), 0.004(t=3.97), 0.001(t=4.92), 0.003(t=3.98), 0.032(t=1.22) and 0.001(t=4.99), respectively]. Totally, 243 patients (26.33%) answered all the questions about asthma correctly. Their medication adherence rating scale (MARS-A) scores were significantly higher than those who answered incompletely correctly (36.23±5.85 vs. 31.77±5.74, P=0.001). Conclusions: The adherence of adult asthma patients was affected by individual and external environment factors. Clinicians should choose individualized methods based on the characteristics of patients. Patient education should be strengthened to improve patients' awareness of the disease at the same time.


Asunto(s)
Asma , Cumplimiento de la Medicación , Masculino , Adulto , Femenino , Humanos , Persona de Mediana Edad , Anciano , Asma/tratamiento farmacológico , Pulmón , China , Hospitales
2.
Eur Rev Med Pharmacol Sci ; 27(1): 66-73, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36647851

RESUMEN

OBJECTIVE: Non-coding RNAs occupy a significant fraction of the human genome, and their biological significance during the pathological process is proved. More and more lncRNAs are reported in cancer research. MATERIALS AND METHODS: To investigate the non-coding RNA's biological relevance with cutaneous skin melanoma, we first compared the survival analysis by combining the most differentially expressed mRNA and non-coding RNA expression values. RESULTS: The result showed that the abundantly expressed mRNAs and lncRNAs have significant effects on the survival of patients. Compared to the mRNAs, these lncRNAs have more impact on the progress of cutaneous skin melanoma. Thus, we combined the two types of RNA factors having significant effects as risk factors to construct the diagnosis model, and the survival analysis confirmed the robustness of the diagnosis model. CONCLUSIONS: In summary, a list of eight lncRNA and five mRNA expression signatures can be used to improve the prognosis prediction of cutaneous skin melanoma, as well as help us to understand the pathogenic mechanism and provide a hint for targeting therapy.


Asunto(s)
Melanoma , ARN Largo no Codificante , Neoplasias Cutáneas , Humanos , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Melanoma/diagnóstico , Melanoma/genética , Pronóstico , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/metabolismo , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética
3.
Phys Chem Chem Phys ; 24(36): 22057-22066, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36070485

RESUMEN

The structural and vibrational properties of pristine graphite and point defects in graphite are studied by tight-binding (TB) calculations using a three-center TB potential model. We showed that the three-center TB potential without "ad hoc" van der Waals interaction corrections can accurately describe the inter-layer distance of graphite and the lowest-energy structures and stabilities of typical point defects in graphite. The results from our TB calculations are in good agreement with those from density-functional theory calculations with van der Waals interaction corrections. We also investigated the vibrational properties to gain better understanding on the localization of vibrational states induced by the point defects. Our calculation results show that although localized or quasi-localized vibrational modes can be found in all defected graphite, the localization induced by Frenkel pair, dual-vacancy, and dual-interstitial defects is much stronger. Atomic displacements associated with the localized vibrational modes induced by these three point defects are also analyzed.

4.
Zhonghua Yi Xue Za Zhi ; 102(10): 735-740, 2022 Mar 15.
Artículo en Chino | MEDLINE | ID: mdl-35280018

RESUMEN

Objective: To investigate the expression of GATA3, SOX10, and p16 in triple-negative breast cancer (TNBC) and analyze their significance and correlation with clinicopathology. Methods: The expressions of GATA3, SOX10 and p16 in 53 cases of TNBC and 50 cases of non-TNBC were detected by immunohistochemical staining. Results: GATA3 and SOX10 were positive in 58.5%(31/53) and 75.5%(40/53) of TNBC, respectively. The expression of SOX10 was significantly higher than that in non-TNBC (P<0.05). SOX10 was positive in 17 of the 22 cases that lacked GATA3 expression (77.3%). The expression of p16 was significantly higher in the TNBC, and the co-expression with SOX10 was significantly increased (P<0.05). The sensitivity, specificity, and AUC under the ROC curve of SOX10 were higher than those of GATA3. The sensitivity of SOX10 was higher than that of p16, but the specificity was lower than that of p16. The AUC of SOX10 was higher than that of p16. AUC of combined detection of GATA3 and SOX10, SOX10 and p16 were higher than that of each antibody alone (P<0.05). The expression of GATA3, SOX10, and p16 had no significant correlation with age, tumor size, and lymph node metastasis. The expression of SOX10 and p16 in grade 3 and basal-like TNBC increased significantly, and their co-expression increased. Conclusions: The expressions of SOX10 and p16 in TNBC are significantly increased. SOX10 is a reliable marker for the diagnosis of TNBC and a supplement to GATA3. Whether p16 is a marker related to the prognosis of TNBC remains to be further studied.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Anticuerpos , Biomarcadores de Tumor/metabolismo , Factor de Transcripción GATA3 , Humanos , Factores de Transcripción SOXE , Neoplasias de la Mama Triple Negativas/metabolismo
5.
Zhonghua Gan Zang Bing Za Zhi ; 30(1): 87-93, 2022 Jan 20.
Artículo en Chino | MEDLINE | ID: mdl-35152675

RESUMEN

Objective: To establish a method for the induction of peripheral blood mononuclear cells to hepatocyte-like cells, and preliminarily investigate cell response to injury under the effect of acetaminophen (APAP). Methods: The surface marker CD45 of peripheral blood mononuclear cells wase detected cells by using flow cytometry and immunofluorescence methods. The cellular morphology of induced hepatocyte-like cells was observed under an inverted microscope. Real-time fluorescent quantitative PCR (RT-PCR) was used to detect the expression level of hepatocyte-specific genes, such as cytochrome (CY) P1A2, CYP3A4, CYP2C9, albumin (ALB), alpha-fetoprotein (AFP), and hepatocyte nuclear factor (HNF)4α mRNA. Immunofluorescence method was used to detect intracellular hepatocyte markers AFP, HNF4α, and ALB expression at the protein level. Biochemical analyzer was used to detect hepatocyte-specific secretory functions of AFP, ALB, and urea. Luciferase chemiluminescence method was used to detect the activity of key drug metabolizing enzyme CYP3A4. Colorimetric assay was used to detect the effect of the drug acetaminophen on hepatocyte-like cells, and alanine aminotransferase (ALT) was used as an indicator of liver cell injury. The statistical differences between the data were compared with t-test and rank-sum test. Results: The positive expression rate of CD45 cell surface markers isolated from peripheral blood mononuclear cells was about 98%, and hepatocyte-like cell morphology changes appeared on 15th day of induction. Compared with isolated mononuclear cells, CYP1A2, CYP3A4, CYP2C9, ALB, AFP and HNF4α mRNA was markedly elevated. The expression level of AFP, ALB and HNF4α protein were equally increased, and the secretory function of AFP, ALB and urea were enhanced. Compared with primary hepatocytes, CYP1A2, CYP2C9, AFP, HNF4α mRNA, and CYP3A4 mRNA did not decrease. The expression levels of AFP, ALB, and HNF4α proteins in the cells did not decrease, and the secretory function of AFP, ALB, and urea did not decrease. In addition, the CYP3A4 enzyme activity produced by hepatocyte-like cells was similar to that of primary hepatocytes. Compared with hepatocyte-like cells incubated without APAP, hepatocyte-like cells incubated with APAP had higher ALT level. Under the effect of APAP, the ALT level of hepatocyte-like cells was higher than isolated mononuclear cells. Conclusion: Peripheral blood mononuclear cells can be induced into hepatocyte-like cells with partial characteristics of hepatocytes, including the activity of CYP3A4, a key enzyme of hepatocyte drug metabolism. Additionally, preliminarily ALT secretory features reflect the hepatocytes injury under the effect of acetaminophen.


Asunto(s)
Acetaminofén , Leucocitos Mononucleares , Acetaminofén/farmacología , Diferenciación Celular , Células Cultivadas , Hepatocitos , ARN Mensajero
6.
J Chem Phys ; 155(19): 194503, 2021 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-34800941

RESUMEN

Al-rich Al-Ce alloys have the possibility of replacing heavier steel and cast irons for use in high-temperature applications. Knowledge about the structures and properties of Al-Ce alloys at the liquid state is vital for optimizing the manufacture process to produce desired alloys. However, reliable molecular dynamics simulation of Al-Ce alloy systems remains a great challenge due to the lack of accurate Al-Ce interatomic potential. Here, an artificial neural network (ANN) deep machine learning (ML) method is used to develop a reliable interatomic potential for Al-Ce alloys. Ab initio molecular dynamics simulation data on the Al-Ce liquid with a small unit cell (∼200 atoms) and on the known Al-Ce crystalline compounds are collected to train the interatomic potential using ANN-ML. The obtained ANN-ML model reproduces well the energies, forces, and atomic structure of the Al90Ce10 liquid and crystalline phases of Al-Ce compounds in comparison with the ab initio results. The developed ANN-ML potential is applied in molecular dynamics simulations to study the structures and properties of the metallic Al90Ce10 liquid, which would provide useful insight into the guiding experimental process to produce desired Al-Ce alloys.

7.
J Physiol Pharmacol ; 72(2)2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34374659

RESUMEN

The Asian ginseng root (Panax ginseng C.A. Meyer) is a very commonly used herbal medicine worldwide. Ginseng fruit, including the berry (or pulp) and seed, is also valuable for several health conditions including immunostimulation and cancer chemoprevention. In this study, the anticancer and anti-proliferative effects of the extracts of ginseng berry and seed were evaluated. The ginsenosides in the ginseng berry concentrate (GBC) and ginseng seed extract (GSE) were analyzed. We then evaluated their anti-colorectal cancer potentials, including antiproliferation, cell cycle arrest, and apoptotic induction. Further investigation consisted of the berry's adaptive immune responses, such as the actions on the differentiation of T helper cells Treg, Th1, and Th17. The major constituents in GBC were ginsenosides Re and Rd, which can be compared to those in the root. The GBC significantly inhibited colon cancer cell growth, and its anti-proliferative effect involved mechanisms including G2/M cell cycle arrest via upregulation of cyclin A and induction of apoptosis via regulation of apoptotic related gene expressions. GBC also downregulated the expressions of pro-inflammatory cytokine genes. For the adaptive immune responses, GBC did not influence Th1 and Treg cell differentiation but significantly inhibited Th17 cell differentiation and thus regulated the balance of Th17/Treg for adaptive immunity. Although no ginsenoside was detected in the GSE, interestingly, it obviously enhanced colon cancer cell proliferation with the underlined details to be determined. Our results suggested that GBC is a promising dietary supplement for cancer chemoprevention and immunomodulation.


Asunto(s)
Neoplasias del Colon , Panax , Apoptosis , Ciclo Celular , Diferenciación Celular , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/prevención & control , Medicamentos Herbarios Chinos , Frutas , Humanos , Inflamación/tratamiento farmacológico , Inflamación/prevención & control , Extractos Vegetales/farmacología
8.
Phys Chem Chem Phys ; 23(8): 4835-4840, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33605963

RESUMEN

Amorphous diamond structures are generated by quenching high-density high-temperature liquid carbon using tight-binding molecular-dynamics simulations. We show that the generated amorphous diamond structures are predominated by strong tetrahedral bonds with the sp3 bonding fraction as high as 97%, thus exhibit an ultra-high incompressibility and a wide band gap close to those of crystalline diamond. A small amount of sp2 bonding defects in the amorphous sample contributes to localized electronic states in the band gap while large local strain gives rise to localization of vibrational modes at both high and low frequency regimes.

9.
Phys Rev E ; 102(4-1): 043213, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33212587

RESUMEN

Ground-state structures of a two-dimensional (2D) system composed of superparamagnetic charged particles are investigated by means of molecular dynamics simulation. The charged particles trapped in a quadratic potential interact with each other via the repulsive, attractive, and magnetic dipole-dipole forces. Simulations are performed within two regimes: a one-component system and a two-component system where the charged particles have the identical charge-to-mass ratio. The effects of magnetic dipole-dipole interaction, mixing ratio of the two species and confinement frequency on the ground-state structures are discussed. It is found that as the strength of the magnetic dipole increases, the charged particles tend to self-organize into chainlike structures. The two species particles exhibit different structural features, depending on the competition of electrostatic repulsive interaction, magnetic dipole-dipole interaction and confinement force. The potential lanes are observed through analyzing the global potential of the magnetic particles, which guide the unmagnetic particles aligning themselves in the direction of the potential lanes.

10.
J Phys Condens Matter ; 32(47): 475001, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32870810

RESUMEN

Monolayer C2N has been successfully synthesized. To explore the enhancement of its stability and the expansion of its potential applications in electronics and optoelectronics, a vertical van der Waals heterostructure is constructed by C2N monolayer integrated with h-BN monolayer. The first-principles calculations based on the density functional theory show that this structure possesses a type-II band alignment with a smaller direct band gap and lager band offsets, suggesting that photo-generated electron-hole pairs can be well spatially separated, and thus an excellent photoelectric and photovoltaic material can be obtained. Also shown is that the electronic properties of such a heterostructure can be effectively regulated by a vertical strain and external electric field. For example, under compressive strain or forward electric field, its band gap can be significantly reduced to enhance light-excitation electron transition further, meanwhile the feature of direct band-gap and large band offsets is always well-preserved. Furthermore, it is found that the intrinsic heterostructure holds a wide optic adsorption range and large adsorption coefficient, and the applied compressive strain or a positive electric field can lead to a wide and high main absorption peak across the near-infrared, visible light, and ultraviolet region, implying that a tuned heterostructure has more promising applications in optoelectronics.

11.
Phys Chem Chem Phys ; 22(33): 18467-18479, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-32778859

RESUMEN

An interatomic potential for the Al-Tb alloy around the composition of Al90Tb10 is developed using the deep neural network (DNN) learning method. The atomic configurations and the corresponding total potential energies and forces on each atom obtained from ab initio molecular dynamics (AIMD) simulations are collected to train a DNN model to construct the interatomic potential for the Al-Tb alloy. We show that the obtained DNN model can well reproduce the energies and forces calculated by AIMD simulations. Molecular dynamics (MD) simulations using the DNN interatomic potential also accurately describe the structural properties of the Al90Tb10 liquid, such as partial pair correlation functions (PPCFs) and bond angle distributions, in comparison with the results from AIMD simulations. Furthermore, the developed DNN interatomic potential predicts the formation energies of the crystalline phases of the Al-Tb system with an accuracy comparable to ab initio calculations. The structure factors of the Al90Tb10 metallic liquid and glass obtained by MD simulations using the developed DNN interatomic potential are also in good agreement with the experimental X-ray diffraction data. The development of short-range order (SRO) in the Al90Tb10 liquid and the undercooled liquid is also analyzed and three dominant SROs, i.e., Al-centered distorted icosahedron (DISICO) and Tb-centered '3661' and '15551' clusters, respectively, are identified.

12.
Phys Chem Chem Phys ; 22(26): 14630-14636, 2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32568353

RESUMEN

We have performed systematic molecular dynamics simulations to study the structures of liquid carbon at 5000 K with the weight density ranging from 1.4 to 3.5 g cm-3, using a three-center tight-binding potential of carbon. The simulation results show that the bonding characteristics of the liquid changes predominately from twofold to threefold, and then to fourfold coordination as the density increases. Signals of two structural changes at the densities of about 1.9 and 3.0 g cm-3 respectively are revealed by the slope changes in the density dependence of structural, electronic and dynamical properties. Our simulation results suggest that there are three distinct liquid carbon phases in this density range. However, further thermodynamics calculations, e.g., free energy calculations, would be required to clarify the possible liquid-liquid transitions.

13.
Clin Transl Oncol ; 22(7): 1013-1022, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31650468

RESUMEN

OBJECTIVE: Chronic inflammation is recognized as a risk factor for colorectal cancer (CRC) development. Baicalin (BI), a major constituent in an anti-inflammatory herb Scutellaria baicalensis, can be biotransformed into baicalein (BE) by the intestinal microbiota. We evaluated the anti-inflammation and anti-CRC effects of the metabolite BE. METHODS: The in vitro biotransformation by human intestinal microbiota from BI into BE has been determined with HPLC. Using a gut-specific ApcMin/+ mouse model, the effects of oral BE on the life span, organ index, and tumor multiplicity were evaluated. The expressions of inflammatory cytokines were determined using ELISA. To verify the in vivo data, the anti-inflammatory and antiproliferative effects of BE were determined with an in vitro cell model. RESULTS: HPLC analysis showed that BI was quickly transformed into BE by the intestinal microbiota. Oral BE (30 mg/kg/day) significantly increased the life span, from 125.2 to 218.4 days (P < 0.01%). BE treatment also decreased intestine index and increased spleen index. Compared with the model group, following BE treatment, tumor numbers were significantly reduced in the small intestine and colon (P < 0.01, P < 0.05, respectively). In the gut tissues, BE treatment significantly reduced inflammatory cytokine levels such as IL-1ß, IL-2, IL-6, IL-10, G-CSF, and GM-CSF. In vitro data supported our in vivo results that the anti-CRC effects of BE were via the inhibition of gut inflammation and induction of cancer cell death. CONCLUSION: Our results suggest that the parent compound BI can be quickly converted into its microbial metabolite BE, which has stronger bioactive effects than BI. Baicalein is an active chemopreventive metabolite for inflammatory associated CRC.


Asunto(s)
Antioxidantes/farmacología , Colon/efectos de los fármacos , Neoplasias Colorrectales/patología , Citocinas/efectos de los fármacos , Flavanonas/farmacología , Intestino Delgado/efectos de los fármacos , Proteína de la Poliposis Adenomatosa del Colon/genética , Animales , Colon/inmunología , Colon/patología , Neoplasias Colorrectales/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Flavanonas/metabolismo , Flavonoides/metabolismo , Microbioma Gastrointestinal , Células HT29 , Humanos , Inflamación/metabolismo , Neoplasias Intestinales/genética , Neoplasias Intestinales/patología , Intestino Delgado/inmunología , Intestino Delgado/patología , Longevidad , Ratones , Carga Tumoral
14.
J Chem Phys ; 151(21): 214502, 2019 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-31822091

RESUMEN

The fast increase in available computation power allowed us to decrease the cooling rate in molecular dynamics (MD) simulation of vitrification by several orders of magnitude. While the reliability of the MD simulation should obviously benefit from this increase in the computational power, in some cases, it led to unexpected results. In particular, Ryltsev et al. [J. Chem. Phys. 149, 164502 (2018)] found that the most popular potentials for the Cu-Zr and Cu-Zr-Al alloys from Mendelev et al. [Philos. Mag. 89, 967 (2009)] and Cheng et al. [Phys. Rev. Lett. 102, 245501 (2009)] do not actually describe good glass forming systems but in contradiction with experiment predict rather fast crystallization of the Cu64.5Zr35.5 alloy which is the well-known example of bulk metallic glasses. In this paper, we present a new Cu-Zr semiempirical potential suitable to simulate vitrification. No crystal nucleation was observed in MD simulation using this potential in the concentration range from 75% to 5% of Zr. Since the new potential leads to about the same liquid structure and viscosity as the Cu-Zr potential from Mendelev et al. [Philos. Mag. 89, 967 (2009)] which failed to describe the good glass formability, our study clearly shows that no reliable conclusions about the glass formability can be deduced based solely on the analysis of the liquid properties and a nucleation/crystal growth study should be performed to address this question.

15.
Eur Rev Med Pharmacol Sci ; 23(20): 8813-8822, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31696468

RESUMEN

OBJECTIVE: To investigate the role of microRNA-15 (miR-15) in the progression of bladder cancer (BC) cell and its underlying mechanism. PATIENTS AND METHODS: Human BC specimens were collected from BC patients during operations. BC cell lines (T24, BIU87, and HT1376) and normal uroepithelial cell lines SV-HUV-1 were cultured. The abilities of cell proliferation and invasion were detected by Methyl thiazolyl tetrazolium (MTT) and transwell assay, respectively. Additionally, the relevant mRNA and protein expressions were measured by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), Western blot and immunohistochemistry, respectively. Furthermore, the luciferase reporter assay was used to verify the target gene of miR-15. Besides, Xenograft tumor formation assay was performed to confirm the effect of miR-15 on tumor growth. RESULTS: A low expression of miR-15 was detected by qRT-PCR, whereas the high expression of B cell-specific Moloney murine leukemia virus integration site 1 (BMI1) was detected by immunocytochemical assay in BC tissues. Moreover, miR-15 expression and BMI1 expression were significantly associated with the overall survival of BC patients. MTT and transwell assay results stated that the up-regulation of miR-15 inhibited BC cell proliferation, migration, and invasion. BMI-1 was verified as a direct target of miR-15 in BC using Luciferase reporter assay. Besides, miR-15 regulated epithelial-mesenchymal transition (EMT)-related makers, protein kinase B (AKT), and the phosphorylation of AKT protein levels in BC using the Western blot assay. Xenograft tumor formation assay indicated that the over-expression of miR-15 inhibited the tumor growth. CONCLUSIONS: We stated that miR-15 suppressed BC cell progression by targeting BMI1 through the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, which provided a potential target for BC treatment.


Asunto(s)
MicroARNs/metabolismo , Complejo Represivo Polycomb 1/metabolismo , Transducción de Señal , Neoplasias de la Vejiga Urinaria/patología , Animales , Antagomirs/metabolismo , Antagomirs/uso terapéutico , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Desnudos , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasa/metabolismo , Complejo Represivo Polycomb 1/química , Complejo Represivo Polycomb 1/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tasa de Supervivencia , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/mortalidad , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Nano Lett ; 19(9): 6058-6064, 2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31398046

RESUMEN

van der Waals (vdW) heterostructures, which are produced by the precise assemblies of varieties of two-dimensional (2D) materials, have demonstrated many novel properties and functionalities. Here we report a nanoplasmonic study of vdW heterostructures that were produced by depositing ordered molecular layers of pentacene on top of graphene. We find through nanoinfrared (IR) imaging that surface plasmons formed due to the collective oscillations of Dirac Fermions in graphene are highly sensitive to the adjacent pentacene layers. In particular, the plasmon wavelength declines systematically but nonlinearly with increasing pentacene thickness. Further analysis and density functional theory (DFT) calculations indicate that the observed peculiar thickness dependence is mainly due to the tunneling-type electron transfer from pentacene to graphene. Our work unveils a new method for tailoring graphene plasmons and deepens our understanding of the intriguing nano-optical phenomena due to interlayer couplings in novel vdW heterostructures.

17.
Sci Rep ; 9(1): 12434, 2019 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-31455835

RESUMEN

In this work, the two-dimensional profile of the light transmission through a prism-like metallic film sample of Au was measured at a wavelength of 632.8 nm in the visible intraband transition region to verify that, beyond the possible mechanisms of overcoming the diffraction limit, a strongly nonuniform optical absorption path length of the light traveling in the metal could induce a lensing effect, thereby narrowing the image of an object. A set of prism-like Au samples with different angles was prepared and experimentally investigated. Due to the nonuniform paths of the light traveling in the Au samples, lens-effect-like phenomena were clearly observed that reduced the imaged size of the beam spot with decreasing light intensity. The experimental measurements presented in the work may provide new insight to better understand the light propagation behavior at a metal/dielectric interface.

18.
Sci Rep ; 9(1): 11276, 2019 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-31375732

RESUMEN

Gravitational stress in general and microgravity (µg) in particular are regarded as major stress factors responsible for immune system dysfunction in space. To assess the effects of alternating µg and hypergravity (hyper-g) on immune cells, the attachment of peripheral blood mononuclear cells (PBMCs) to adhesion molecules under flow conditions and the antigen-induced immune activation in whole blood were investigated in parabolic flight (PF). In contrast to hyper-g (1.8 g) and control conditions (1 g), flow and rolling speed of PBMCs were moderately accelerated during µg-periods which were accompanied by a clear reduction in rolling rate. Whole blood analyses revealed a "primed" state of monocytes after PF with potentiated antigen-induced pro-inflammatory cytokine responses. At the same time, concentrations of anti-inflammatory cytokines were increased and monocytes displayed a surface molecule pattern that indicated immunosuppression. The results suggest an immunologic counterbalance to avoid disproportionate immune responses. Understanding the interrelation of immune system impairing and enhancing effects under different gravitational conditions may support the design of countermeasures to mitigate immune deficiencies in space.


Asunto(s)
Hipergravedad/efectos adversos , Leucocitos Mononucleares/inmunología , Vuelo Espacial , Simulación de Ingravidez/efectos adversos , Adhesión Celular/inmunología , Moléculas de Adhesión Celular/inmunología , Moléculas de Adhesión Celular/metabolismo , Células Cultivadas , Citocinas/inmunología , Citocinas/metabolismo , Femenino , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad , Cultivo Primario de Células
19.
Sci Rep ; 9(1): 6692, 2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31040308

RESUMEN

Using an effective genetic algorithm, we uncover the structure of a metastable Al41Sm5 phase that supplements its family sharing similar short-range orders. The phase evolves upon heating an amorphous Al-9.7 at.% Sm ribbon, produced by melt-spinning. The dynamical phase selection is discussed with respect to the structural connections between the short-range packing motifs in the amorphous precursor and those observed in the selected phases. The phase elucidated here is one of several newly discovered large-unit-cell phases found to form during devitrification from the glass in this binary system, further illustrating the power and efficiency of our approach, the important role of structural hierarchy in phase selection, and the richness of the metastable phase landscape accessible from the glassy structure.

20.
Zhonghua Yi Xue Za Zhi ; 99(16): 1207-1209, 2019 Apr 23.
Artículo en Chino | MEDLINE | ID: mdl-31060157
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