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1.
Ann Vasc Surg ; 66: 406-414, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31918036

RESUMEN

BACKGROUND: The percutaneous access site of transfemoral transcatheter aortic valve implantation (TAVI) procedures is commonly closed using a preclosure technique with suture-type closure devices. We sought to evaluate the predictors and outcomes of percutaneous closure device (PCD) failure during transfemoral TAVI. METHODS AND RESULTS: This single-center retrospective analysis included 184 patients who underwent transfemoral TAVI using 2 ProGlide sutures for severe aortic stenosis between July 2011 and September 2018. PCD failure was observed in 11.4%. The causes of PCD failure included 5 cases of insufficient hemostasis, 13 cases of arterial stenosis or occlusion, and 3 cases of dissection. Closure failures were managed by surgical repair in 10 patients and endovascular treatment in 11 patients. In a multivariate binary logistic model, a minimum lumen diameter of the common femoral artery (CFA) (odds ratio [OR] 0.35, 95% confidence interval [CI] 0.15-0.83, P = 0.017) and left femoral access (OR 2.89, 95% CI 1.01-8.30, P = 0.048) was identified as a predictor of PCD failure. PCD failure was not associated with increased mortality (0% vs. 2.5%, P = 1.000) or a major adverse cardiovascular event (MACE; 4.8% vs. 4.3%, P = 1.000) at 30 days. CONCLUSIONS: PCD failures were not uncommon in patients undergoing percutaneous transfemoral TAVI. Small CFA diameter and left femoral access are predictors of PCD failure. However, PCD failures were not associated with increased mortality or MACE.


Asunto(s)
Cateterismo Periférico/efectos adversos , Arteria Femoral , Hemorragia/prevención & control , Técnicas Hemostáticas/efectos adversos , Técnicas Hemostáticas/instrumentación , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Dispositivos de Cierre Vascular , Anciano , Anciano de 80 o más Años , Arteriopatías Oclusivas/etiología , Cateterismo Periférico/mortalidad , Falla de Equipo , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/lesiones , Hemorragia/etiología , Técnicas Hemostáticas/mortalidad , Humanos , Masculino , Punciones , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Resultado del Tratamiento , Lesiones del Sistema Vascular/etiología
2.
Polymers (Basel) ; 15(10)2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37242846

RESUMEN

This research aimed to develop a simple and cost-effective method for fabricating electropositive membranes for highly efficient water filtration. Electropositive membranes are novel functional membranes with electropositive properties and can filter electronegative viruses and bacteria using electrostatic attraction. Because electropositive membranes do not rely on physical filtration, they exhibit high flux characteristics compared with conventional membranes. This study presents a simple dipping process for fabricating boehmite/SiO2/PVDF electropositive membranes by modifying an electrospun SiO2/PVDF host membrane using electropositive boehmite nanoparticles (NPs). The surface modification enhanced the filtration performance of the membrane, as revealed by electronegatively charged polystyrene (PS) NPs as a bacteria model. The boehmite/SiO2/PVDF electropositive membrane, with an average pore size of 0.30 µm, could successfully filter out 0.20 µm PS particles. The rejection rate was comparable to that of Millipore GSWP, a commercial filter with a pore size of 0.22 µm, which can filter out 0.20 µm particles via physical sieving. In addition, the water flux of the boehmite/SiO2/PVDF electropositive membrane was twice that of Millipore GSWP, demonstrating the potential of the electropositive membrane in water purification and disinfection.

3.
Coron Artery Dis ; 31(1): e44-e50, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34347637

RESUMEN

BACKGROUND: Cholesterol control with statins has been shown to have beneficial effects in coronary artery disease. However, the relationship between initial very low low-density lipoprotein (LDL) cholesterol levels and long-term clinical outcomes in patients with acute myocardial infarction (AMI) remains unclear. METHODS: A total of 8741 (mean age: 64.6 ± 12.7 years, men) consecutive AMI patients treated with drug-eluting stents were entered into the Korea Acute Myocardial Infarction Registry from November 2011 to December 2015. Patients were divided into six groups according to whether they were taking statins (on-statin group) or not (statin naive group) and depending on their LDL cholesterol level at admission (<70, 70-99, 100-129, 130-159, >160 mg/dl). Clinical outcomes at 24 months in patients with AMI were examined. RESULTS: The incidence of risk factors including hypertension, diabetes, coronary artery disease and heart failure was lower as LDL cholesterol increased, except in the on-statin group. Clinical outcomes, including total mortality at 24 months, showed better outcomes in those with high LDL cholesterol than those with low LDL cholesterol, except in the statin group. In the statin-naïve group, the higher the LDL cholesterol level, the higher the rate of 24-month survival. In a Cox regression model, initial low LDL cholesterol was an independent predictor of mortality at 24 months after adjusting for baseline confounding factors. CONCLUSIONS: At admission, a very low LDL cholesterol level (<70 mg/dL) in statin-naïve AMI patients undergoing percutaneous coronary intervention was independently associated with higher mortality at 24 months.


Asunto(s)
Lipoproteínas LDL/análisis , Infarto del Miocardio/complicaciones , Anciano , Femenino , Humanos , Estimación de Kaplan-Meier , Lipoproteínas LDL/sangre , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Infarto del Miocardio/mortalidad , Pronóstico , Modelos de Riesgos Proporcionales , República de Corea/epidemiología , Factores de Riesgo
4.
Korean J Intern Med ; 36(2): 352-361, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32564571

RESUMEN

BACKGROUND/AIMS: Coronary endothelial and microvascular function play important roles in cardiovascular disease. We aimed to evaluate the effect of ticagrelor on coronary artery function and tested the antiplatelet effect of low dose ticagrelor in East-Asian patients. METHODS: Sixty-one consecutive patients with non-significant coronary disease were included in the study. Initially, patients were randomized in 1:1:1 ratio to receive drugs: ticagrelor 90 mg twice a day (bid; n = 22), ticagrelor 45 mg bid (n = 19) or clopidogrel 75 mg once a day (qd; n = 20) and then divided into two groups (ticagrelor vs clopidogrel) for evaluation of coronary artery function, and three groups for evaluation of antiplatelet function. Endothelial dysfunction was measured by coronary flow reserve (CFR), and changes in the levels of asymmetric dimethylarginine (ADMA), cluster of differentiation (CD) 40 ligand, and P-selectin. Microvascular function was evaluated as index of microvascular resistance (IMR). Platelet reactivity was assessed by VerifyNow P2Y12 assay. RESULTS: The levels of CFR, ADMA, and CD 40 ligand were not different between the two groups. However, P-selectin was lower in the ticagrelor group compared with clopidogrel group. IMR was significantly lower in the ticagrelor group compared with clopidogrel group (median, 15.0 [interquartile range, 12.0 to 21.0] vs. 47.5 [23.0 to 67.5], p = 0.014). There was significant difference in platelet inhibition among the three groups (ticagrelor 90 mg bid vs. ticagrelor 45 mg bid vs. clopidogrel 75 mg qd; 85.57 ± 47.63 vs. 120.33 ± 51.09 vs. 256.42 ± 55.10, p < 0.001). CONCLUSION: It is hypothesized that ticagrelor might ameliorate the coronary microvascular function. When compared with clopidogrel, low dose ticagrelor exhibited satisfactory antiplatelet effect in the present study.


Asunto(s)
Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Plaquetas , Clopidogrel/efectos adversos , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Humanos , Inhibidores de Agregación Plaquetaria/efectos adversos , Antagonistas del Receptor Purinérgico P2Y/efectos adversos , Ticagrelor/efectos adversos
5.
Clin Hypertens ; 27(1): 15, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34332647

RESUMEN

BACKGROUND: It is most important to measure blood pressure (BP) exactly in treating hypertension. Recent recommendations for diagnosing hypertension clearly acknowledge that an increase in BP attributable to the "whitecoat response" is frequently associated with manual BP recordings performed in community-based practice. However, there was no data about after-consult (AC) BP that could reduce whitecoat effect. So we evaluated before-consult (BC) and AC routine clinic BP and research based automated office blood pressure (AOBP) measured. METHODS: The study population consisted of 82 consecutive patients with hypertension between April 2019 and December 2019. We measured routine clinic BP and AOBP before and after see a doctor, respectively. Seated blood pressure and pulse are measured at each time after a rest period using an automated device as it offers reduced potential for observer biases. AOBP was measured and measuring BP 3 times un-observed. We compared each BP parameter for identifying exact resting BP state. RESULTS: There was significant difference between BC and AC systolic BP (135.37 ± 16.90 vs. 131.95 ± 16.40 mmHg, p = 0.015). However there was no difference in the BC and AC diastolic blood pressure (73.75 ± 11.85 vs. 74.42 ± 11.71 mmHg, p = 0.415). In the AOBP comparison, there was also significant difference (BC systolic AOBP vs. AC systolic AOBP, 125.17 ± 14.41 vs. 122.98 ± 14.09 mmHg, p = 0.006; BC diastolic ABOB vs. AC diastolic AOBP, 71.99 ± 10.49 vs. 70.99 ± 9.83, p = 0.038). CONCLUSIONS: In our study, AC AOBP was most lowest representing resting state. Although AC BP was higher than BC AOBP, it might be used as alternative measurement for reducing whitecoat effect in the routine clinical practice.

6.
ACS Appl Mater Interfaces ; 13(45): 53767-53776, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34739203

RESUMEN

Fluorine (F) atoms with the highest electronegativity and low polarizability can easily modify the surface and composition of carbon-based electrode materials. However, this is accompanied by complete irreversibility and uncontrolled reactivity, thus hindering their use in rechargeable electronic devices. Therefore, understanding the electrochemical effects of the C-F configuration might lead to achieving superior electrochemical properties. Here, we demonstrate that the fluorinated and simultaneously reduced graphene oxide (FrGO) was easily synthesized through direct gas fluorination. The as-prepared 11%-FrGO electrode exhibited a high capacity (1365 mAh g-1 at 0.1 A g-1), remarkable rate capability, and good stability (64% retention after 1000 cycles at 5 A g-1). Furthermore, the annealed FrGO (11%-FrGO(A)) electrode in which the C-F bond configurations were controlled by facile thermal treatment shows long-term stability (80% retention after 1000 cycles at 5 A g-1). Above a certain content, F atoms enhance Li-ion adsorption and electron transfer, accelerate Li-ion diffusion, and facilitate the formation of a solid electrolyte interphase layer. In particular, the C-F configuration plays a significant role in retaining the capacity under harsh recharging conditions. The results in this study could provide valuable insights into the field of rechargeable devices.

7.
ACS Appl Mater Interfaces ; 13(6): 7161-7170, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33539708

RESUMEN

Si-based anode materials are considered as potential materials for high-energy lithium-ion batteries (LIBs) with the advantages of high specific capacities and low operating voltages. However, significant initial capacity loss and large volume variations during cycles are the primary restrictions for the practical application of Si-based anodes. Herein, we propose an affordable and scalable synthesis of double-layered SiOx/Mg2SiO4/SiOx composites through the magnesiothermic reduction of micro-sized SiO with Mg metal powder at 750 °C for 2 h. The distinctive morphology and microstructure of the double-layered SiOx/Mg2SiO4/SiOx composite are beneficial as they remarkably improve the reversibility in the first cycle and completely suppress the volume variations during cycling. In our material design, the outermost layer with a highly porous SiOx structure provides abundant active sites by securing a pathway for efficient access to electrons and electrolytes. The inner layer of Mg2SiO4 can constrain the large volume expansion to increase the initial Coulombic efficiency (ICE). Owing to these promising structural features, the composite prepared with a 2:1 molar ratio of SiO to Mg exhibited initial charge and discharge capacities of 1826 and 1381 mA h g-1, respectively, with an ICE of 75.6%. Moreover, it showed a stable cycle performance, maintaining high capacity retention of up to >86.0% even after 300 cycles. The proposed approach provides practical insight into the mass production of advanced anode materials for high-energy LIBs.

8.
Int J Pharm ; 603: 120670, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33964337

RESUMEN

The present study aims to develop curcumin-loaded nanostructured lipid carriers (CUR-NLCs) and investigate their neuroprotective effects in lipopolysaccharide (LPS)-induced depression and anxiety model. Nanotemplate engineering technique was used to prepare CUR-NLCs with Compritol 888 ATO and oleic acid as solid and liquid lipid, respectively. Poloxamer 188, Tween 80 and Span 80 were used as stabilizing agents for solid-liquid lipid core. The physicochemical parameters of CUR-NLCs were determined followed by in vitro drug release and in vivo neuroprotective activity in rats. The optimized CUR-NLCs demonstrated nanometric particle size of 147.8 nm, surface charge of -32.8 mV and incorporation efficiency of 91.0%. CUR-NLCs showed initial rapid followed by a sustained drug release reaching up to 73% after 24 h. CUR-NLCs significantly elevated struggling time and decreased immobility time in forced swim and tail suspension tests. A substantial increase in time spent and number of entries into the light and open compartments was observed in light-dark box and elevated plus maze models. CUR-NLCs improved the tissue architecture and suppressed the expression of p-NF-κB, TNF-α and COX-2 in brain tissues from histological and immunohistochemical analysis. CUR-NLCs improved the neuroprotective effect of curcumin and can be used as a potential therapeutics for depression and anxiety.


Asunto(s)
Curcumina , Nanoestructuras , Animales , Antidepresivos , Ansiedad/tratamiento farmacológico , Depresión/tratamiento farmacológico , Portadores de Fármacos , Lipopolisacáridos , Tamaño de la Partícula , Ratas
9.
Colloids Surf B Biointerfaces ; 194: 111209, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32599505

RESUMEN

The potential of duloxetine-loaded solid lipid nanoparticles (DLX-SLNs) for enhanced antidepressant activity was investigated in the current study. Nano-template engineering technology was successfully employed for the preparation of DLX-SLNs. In vivo forced swim and tail suspension tests were used to evaluate behavioral changes of rats in lipopolysaccharide-induced depression. The determination of brain-derived neurotropic factor (BDNF) in brain and plasma was carried out using enzyme-linked immunosorbent assay. The incorporation efficiency of optimized DLX-SLNs formulation was found to be 80 % with particle size of 114.5 nm, PDI of 0.29 and zeta potential of -18.2 mV. Powder X-ray diffractometry and differential scanning calorimetry demonstrated sufficient incorporation into lipid matrix and amorphous behavior of DLX. In vitro release profile of DLX-SLNs showed a sustained release achieving a cumulative amount of 52.97 % for 24 h. DLX-SLNs showed a significant decrease in immobility time in forced swim and tail suspension tests. DLX-SLNs increased BDNF levels in plasma and brain after 2 weeks. Immunohistochemistry results demonstrated significant reduction in the expression of tumor necrosis factor-α and cyclooxygenase enzyme-2 in brain. In conclusion, solid lipid nanoparticles can be utilized as a potential carrier for the delivery of antidepressant drugs into the brain.


Asunto(s)
Lipopolisacáridos , Nanopartículas , Animales , Antidepresivos/farmacología , Portadores de Fármacos , Clorhidrato de Duloxetina , Tamaño de la Partícula , Ratas
10.
Pharmaceutics ; 12(12)2020 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-33291312

RESUMEN

During the past two decades, the clinical use of biopharmaceutical products has markedly increased because of their obvious advantages over conventional small-molecule drug products. These advantages include better specificity, potency, targeting abilities, and reduced side effects. Despite the substantial clinical and commercial success, the macromolecular structure and intrinsic instability of biopharmaceuticals make their formulation and administration challenging and render parenteral delivery as the only viable option in most cases. The use of nanocarriers for efficient delivery of biopharmaceuticals is essential due to their practical benefits such as protecting from degradation in a hostile physiological environment, enhancing plasma half-life and retention time, facilitating absorption through the epithelium, providing site-specific delivery, and improving access to intracellular targets. In the current review, we highlight the clinical and commercial success of biopharmaceuticals and the overall applications and potential of nanocarriers in biopharmaceuticals delivery. Effective applications of nanocarriers for biopharmaceuticals delivery via invasive and noninvasive routes (oral, pulmonary, nasal, and skin) are presented here. The presented data undoubtedly demonstrate the great potential of combining nanocarriers with biopharmaceuticals to improve healthcare products in the future clinical landscape. In conclusion, nanocarriers are promising delivery tool for the hormones, cytokines, nucleic acids, vaccines, antibodies, enzymes, and gene- and cell-based therapeutics for the treatment of multiple pathological conditions.

11.
Acta Pharm Sin B ; 10(12): 2362-2373, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33354507

RESUMEN

The short release half-life of carbon monoxide (CO) is a major obstacle to the effective therapeutic use of carbon monoxide-releasing molecule-2 (CORM-2). The potential of CORM-2-entrapped ultradeformable liposomes (CORM-2-UDLs) to enhance the release half-life of CO and alleviate skin inflammation was investigated in the present study. CORM-2-UDLs were prepared by using soy phosphatidylcholine to form lipid bilayers and Tween 80 as an edge activator. The deformability of CORM-2-UDLs was measured and compared with that of conventional liposomes by passing formulations through a filter device at a constant pressure. The release profile of CO from CORM-2-UDLs was evaluated by myoglobin assay. In vitro and in vivo anti-inflammatory effects of CORM-2-UDLs were assessed in lipopolysaccharide-stimulated macrophages and TPA-induced ear edema model, respectively. The deformability of the optimized CORM-2-UDLs was 2.3 times higher than conventional liposomes. CORM-2-UDLs significantly prolonged the release half-life of CO from 30 s in a CORM-2 solution to 21.6 min. CORM-2-UDLs demonstrated in vitro anti-inflammatory activity by decreasing nitrite production and pro-inflammatory cytokine levels. Furthermore, CORM-2-UDLs successfully ameliorated skin inflammation by reducing ear edema, pathological scores, neutrophil accumulation, and inflammatory cytokines expression. The results demonstrate that CORM-2-UDLs could be used as promising therapeutics against acute skin inflammation.

13.
Nanoscale ; 9(44): 17167-17173, 2017 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-28786463

RESUMEN

We demonstrate that a bi-interlayer consisting of water-free poly(3,4-ethylenedioxythiophene) (PEDOT) and fluorinated reduced graphene oxide (FrGO) noticeably enhances the efficiency and the stability of the normal-structure perovskite solar cells (PeSCs). With simple and low temperature solution-processing, the PeSC employing the PEDOT + FrGO interlayer exhibits a significantly improved power conversion efficiency (PCE) of 14.9%. Comprehensive investigations indicate that the enhanced PCE is mostly attributed to the retarded recombination in the devices. The minimized recombination phenomena are related to the interfacial dipoles at the PEDOT/FrGO interface, which facilitates the electron-blocking and the higher built-in potential in the devices. Furthermore, the PEDOT + FrGO device shows a better stability by maintaining 70% of the initial PCE over the 30 days exposure to ambient conditions. This is because the more hydrophobic graphitic sheets of the FrGO on the PEDOT further protect the perovskite films from oxygen/water penetration. Consequently, the introduction of composite interfacial layers including graphene derivatives can be an effective and versatile strategy for high-performing, stable, and cost-effective PeSCs.

14.
ACS Appl Mater Interfaces ; 9(33): 27832-27838, 2017 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-28752996

RESUMEN

Despite the potential of roll-to-roll processing for the fabrication of perovskite films, the realization of highly efficient and reproducible perovskite solar cells (PeSCs) through continuous coating techniques and low-temperature processing is still challenging. Here, we demonstrate that efficient and reliable CH3NH3PbI3 (MAPbI3) films fabricated by a printing process can be achieved through synergetic effects of binary processing additives, N-cyclohexyl-2-pyrrolidone (CHP) and dimethyl sulfoxide (DMSO). Notably, these perovskite films are deposited from premixed perovskite solutions for facile one-step processing under a room-temperature and ambient atmosphere. The CHP molecules result in the uniform and homogeneous perovskite films even in the one-step slot-die system, which originate from the high boiling point and low vapor pressure of CHP. Meanwhile, the DMSO molecules facilitate the growth of perovskite grains by forming intermediate states with the perovskite precursor molecules. Consequently, fully printed PeSC based on the binary additive system exhibits a high PCE of 12.56% with a high reproducibility.

15.
Sci Rep ; 7: 41190, 2017 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-28106126

RESUMEN

Amorphous molybdenum sulfide (MoSx) is covalently anchored to reduced graphene oxide (r-GO) via a simple one-pot reaction, thereby inducing the reduction of GO and simultaneous doping of heteroatoms on the GO. The oxygen atoms form a bridged between MoSx and GO and play a crucial role in the fine dispersion of the MoSx particles, control of planar MoSx growth, and increase of exposed active sulfur sites. This bridging leads to highly efficient (-157 mV overpotential and 41 mV/decade Tafel slope) and stable (95% versus initial activity after 1000 cycles) electrocatalyst for hydrogen evolution.

16.
Mol Cells ; 19(3): 356-64, 2005 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-15995352

RESUMEN

Intramolecular excimer formation of 1,3-di(1-pyrenyl) propane(Py-3-Py) and fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) were used to evaluate the effect of ethanol on the rate and range of lateral and rotational mobilities of bulk bilayer structures of synaptosomal plasma membrane vesicles (SPMVs) from the bovine cerebral cortex. Ethanol increased the excimer to monomer fluorescence intensity ratio (I'/I) of Py-3-Py in the SPMVs. Selective quenching of both DPH and Py-3-Py by trinitrophenyl groups was used to examine the range of transbilayer asymmetric rotational mobility and the rate and range of transbilayer asymmetric lateral mobility of SPMVs. Ethanol increased the rotational and lateral mobility of the outer monolayer more than of the inner one. Thus ethanol has a selective fluidizing effect within the transbilayer domains of the SPMVs. Radiationless energy transfer from the tryptophans of membrane proteins to Py-3-Py was used to examine both the effect of ethanol on annular lipid fluidity and protein distribution in the SPMVs. Ethanol increased annular lipid fluidity and also caused membrane proteins to cluster. These effects on neuronal membranes may be responsible for some, though not all, of the general anesthetic actions of ethanol.


Asunto(s)
Membrana Celular/efectos de los fármacos , Corteza Cerebral/citología , Etanol/farmacología , Fluidez de la Membrana/efectos de los fármacos , Sinaptosomas/efectos de los fármacos , Animales , Bovinos , Corteza Cerebral/efectos de los fármacos , Difenilhexatrieno , Colorantes Fluorescentes , Fluorometría , Membrana Dobles de Lípidos/química , Proteínas de la Membrana/química , Proteínas de la Membrana/efectos de los fármacos , Pirenos/química , Ácido Trinitrobencenosulfónico
17.
Sci Rep ; 5: 9141, 2015 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-25771823

RESUMEN

The drying process of graphene-polymer composites fabricated by solution-processing for excellent dispersion is time consuming and suffers from a restacking problem. Here, we have developed an innovative method to fabricate polymer composites with well dispersed graphene particles in the matrix resin by using solvent free powder mixing and in-situ polymerization of a low viscosity oligomer resin. We also prepared composites filled with up to 20 wt% of graphene particles by the solvent free process while maintaining a high degree of dispersion. The electrical conductivity of the composite, one of the most significant properties affected by the dispersion, was consistent with the theoretically obtained effective electrical conductivity based on the mean field micromechanical analysis with the Mori-Tanaka model assuming ideal dispersion. It can be confirmed by looking at the statistical results of the filler-to-filler distance obtained from the digital processing of the fracture surface images that the various oxygenated functional groups of graphene oxide can help improve the dispersion of the filler and that the introduction of large phenyl groups to the graphene basal plane has a positive effect on the dispersion.

18.
Rev Sci Instrum ; 85(2): 02A903, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24593482

RESUMEN

A 14.5 GHz Electron Cyclotron Resonance ion source (ECRIS) has been made to produce C(4+) beam for using a carbon therapy facility and recently tested at KAERI. Highly charged carbon ions have been successfully extracted. When using only CO2 gas, the beam current of C(4+) was almost 14 µA at 15 kV extraction voltage. To get higher current of the C(4+) beam, while optimizing confinement magnetic field configuration (e.g., axial strengths at minimum and extraction side), gas-mixing (CO2/He), and biased disk were introduced. When the gas mixing ratio of the CO2/He gas is 1:8 at an operational pressure of 5 × 10(-7) mbar and the disk was biased to -150 V relative to the ion source body, the highest current of the C(4+) beam was achieved to be 50 µA, more than three times higher than previously observed only with CO2 gas. Some details on the operating conditions of the ECRIS were discussed.

19.
Virology ; 452-453: 264-78, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24606704

RESUMEN

Different isolates of Alternanthera mosaic virus (AltMV; Potexvirus), including four infectious clones derived from AltMV-SP, induce distinct systemic symptoms in Nicotiana benthamiana. Virus accumulation was enhanced at 15 °C compared to 25 °C; severe clone AltMV 3-7 induced systemic necrosis (SN) and plant death at 15 °C. No interaction with potexvirus resistance gene Rx was detected, although SN was ablated by silencing of SGT1, as for other cases of potexvirus-induced necrosis. Substitution of AltMV 3-7 coat protein (CPSP) with that from AltMV-Po (CP(Po)) eliminated SN at 15 °C, and ameliorated symptoms in Alternanthera dentata and soybean. Substitution of only two residues from CP(Po) [either MN(13,14)ID or LA(76,77)IS] efficiently ablated SN in N. benthamiana. CPSP but not CP(Po) interacted with Arabidopsis boron transporter protein AtBOR1 by yeast two-hybrid assay; N. benthamiana homolog NbBOR1 interacted more strongly with CPSP than CP(Po) in bimolecular fluorescence complementation, and may affect recognition of CP as an elicitor of SN.


Asunto(s)
Antiportadores/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de la Cápside/metabolismo , Necrosis , Nicotiana/virología , Enfermedades de las Plantas/virología , Potexvirus/metabolismo , Secuencia de Aminoácidos , Antiportadores/genética , Arabidopsis/genética , Arabidopsis/virología , Proteínas de Arabidopsis/genética , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Silenciador del Gen , Datos de Secuencia Molecular , Enfermedades de las Plantas/genética , Potexvirus/química , Potexvirus/genética , Alineación de Secuencia , Temperatura , Nicotiana/genética , Nicotiana/fisiología
20.
Nanoscale ; 6(13): 7183-7, 2014 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-24801948

RESUMEN

A one-step reduction and functionalization of graphene oxide (FrGO) was easily achieved using a novel phenylhydrazine-based reductant containing fluorine atoms, which can induce p-type doping due to its high electronegativity. The FrGO-based OPV exhibited a high power conversion efficiency of ∼6.71% and a superior OPV-stability to commercial PEDOT:PSS.

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