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1.
Phytopathology ; 109(9): 1638-1647, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31044662

RESUMO

Infectious clones of Korean turnip mosaic virus (TuMV) isolates KIH1 and HJY1 share 88.1% genomic nucleotides and 96.4% polyprotein amino acid identity, and they induce systemic necrosis or mild mosaic, respectively, in Nicotiana benthamiana. Chimeric constructs between these isolates exchanged the 5', central, and 3' domains of KIH1 (K) and HJY1 (H), where the order of the letters indicates the origin of these domains. KIH1 and chimeras KHH and KKH induced systemic necrosis, whereas HJY1 and chimeras HHK, HKK, and HKH induced mild symptoms, indicating the determinant of necrosis to be within the 5' 3.9 kb of KIH1; amino acid identities of the included P1, Helper component protease, P3, 6K1, and cylindrical inclusion N-terminal domain were 90.06, 98.91, 93.80, 100, and 100%, respectively. Expression of P1 or P3 from a potato virus X vector yielded symptom differences only between P3 of KIH1 and HJY1, implicating a role for P3 in necrosis in N. benthamiana. Chimera KKH infected Brassica rapa var. pekinensis 'Norang', which was resistant to both KIH1 and HJY1, indicating that two separate TuMV determinants are required to overcome the resistance. Ability of diverse TuMV isolates, chimeras, and recombinants to overcome resistance in breeding lines may allow identification of novel resistance genes.


Assuntos
Brassica , Nicotiana , Brassica/virologia , Quimera , Doenças das Plantas/microbiologia , Potyvirus , Nicotiana/virologia
2.
J Environ Sci (China) ; 24(5): 897-902, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22893968

RESUMO

Aqueous 1,8-diamino-p-menthane (KIER-C3) and commercially available amine solutions were tested for CO2 absorption. A 2-amino-2-methyl-1-propanol (AMP) solution with an addition of KIER-C3 showed 9.3% and 31.6% higher absorption rate for CO2 than the AMP solution with an addition of monoethanolamine (MEA) and ammonia (NH3), respectively. The reaction rate constant for CO2 absorption by the AMP/KIER-C3 solution was determined by the following equation: k2,AMP/C3 = 7.702 x 10(6) exp (-2248.03/T). A CO2 loading ratio of the AMP/KIER-C3 solution was also 2 and 3.4-times higher than that of the AMP/NH3 solution and the AMP/MEA solution, respectively. Based on the experimental results, KIER-C3 may be used as an excellent additive to increase CO2 absorption capability of AMP.


Assuntos
Dióxido de Carbono/isolamento & purificação , Cicloexanos/química , Diaminas/química , Propanolaminas/química , Solventes/química , Absorção , Amônia/química , Monoterpenos Cicloexânicos , Difusão , Etanolamina/química , Cinética , Pressão Parcial , Solubilidade , Soluções , Temperatura
3.
ACS Omega ; 7(42): 37825-37833, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36312342

RESUMO

Sustainable and scalable fabrication of electrode materials with high energy and power densities is paramount for the development of future electrochemical energy storage devices. The electrode material of a supercapacitor should have high electrical conductivity, good thermal and chemical stability, and a high surface area per unit volume (or per unit mass). Researchers have made great efforts to use two-dimensional (2D) nanomaterials, but the separated 2D plates are re-stacked during processing for electrode fabrication, impeding the transport of ions and reducing the number of active sites. We developed a novel process for manufacturing thin and flexible electrodes using a 2D material (MXene,Ti3AlC2) and a conducting polymer (poly(3,4-ethylenedioxythiophene), PEDOT). Because the PEDOT layer is electrochemically synthesized, it does not contain the activator poly(styrene sulfonate). The electrospray deposition technique solves the restacking problem and facilitates the infilling of the gel electrolyte by forming a highly porous open structure across the entire electrode. In the PEDOT/MXene multilayered electrode, the double-layer capacitance increased substantially because of a dramatic increase in the number of accessible sites through the MXene layer. Although applied to solid supercapacitors, these new supercapacitors outperform most aqueous electrolyte supercapacitors as well as other solid supercapacitors.

4.
ACS Omega ; 7(4): 3341-3347, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128244

RESUMO

In this work, we investigated the effect of a change in the molecular structure and ensuing molar mass change of a matrix polymer (polyamide 6, Ny 6) on droplet deformation of a dispersed thermotropic liquid crystalline polymer (TLCP, a poly(ester amide)) in shear flow. This study focuses on a total capillary number (the sum of the shear capillary number and the elasticity capillary number) and the viscosity ratio between the TLCP and Ny 6, for the morphological development and mechanical performance of TLCP/Ny 6 blends. In contrast to Ny 6, which has a lower melt viscosity than the TLCP melt, a modified Ny 6 (m-Ny 6) with ca. 2 orders higher melt viscosity than that of Ny 6 at a shear rate of 1 s-1 was found to facilitate the deformation of the TLCP phase. A total capillary number was defined to characterize the viscoelasticity effect on droplet deformation in the blend system. The first normal stress difference obtained from the viscosity curve using Steller's method was used for the evaluation of the elasticity capillary number. The total capillary number for the Ny 6 blend was far less than the critical capillary number and was insufficient for the dispersed TLCP droplets to be deformed. The shear capillary number of the m-Ny 6 blend was greater than the critical capillary number but was still insufficient for droplet deformation into fibril shapes. The total capillary number, including the elastic capillary number, was sufficiently greater than the critical capillary number for deformation of the dispersed TLCP droplets. Morphological observations and a comparison with the theoretical work confirmed the importance of the viscoelasticity of the melt in the immiscible Ny 6/TLCP blends for in situ composite fabrication in shear flow. Both the high viscosity and the first normal stress difference of m-Ny 6 promote the deformation and fibrillation of the dispersed TLCP droplets.

5.
Materials (Basel) ; 15(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35591740

RESUMO

This study investigated the hydrogen embrittlement (HE) characteristics of advanced high-strength steels (AHSSs). Two different types of AHSSs with a tensile strength of 1.2 GPa were investigated. Slow strain rate tests (SSRTs) were performed under various applied potentials (Eapp) to identify the mechanism with the greatest effect on the embrittlement of the specimens. The SSRT results revealed that, as the Eapp increased, the elongation tended to increase, even when a potential exceeding the corrosion potential was applied. Both types of AHSSs exhibited embrittled fracture behavior that was dominated by HE. The fractured SSRT specimens were subjected to a thermal desorption spectroscopy analysis, revealing that diffusible hydrogen was trapped mainly at the grain boundaries and dislocations (i.e., reversible hydrogen-trapping sites). The micro-analysis results revealed that the poor HE resistance of the specimens was attributed to the more reversible hydrogen-trapping sites.

6.
Materials (Basel) ; 14(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066848

RESUMO

This study investigated the effect of Cr alloying element on the corrosion properties of automotive carbon steel (0.1C, 0.5Si, 2.5Mn, Fe Bal., composition given in wt.%) in aqueous and atmospheric conditions using electrochemical measurement and cyclic corrosion tests. Three steels with 0, 0.3, and 0.5 wt.% Cr were studied by electrochemical impedance spectroscopy. Polarization resistance (Rp) of 0.3 Cr and 0.5 Cr steels was higher than that of 0 Cr steel, and the Rp also increased as the Cr content increased. Therefore, Cr increases the corrosion resistance of automotive carbon steel immersed in a chloride ion (Cl-)-containing aqueous solution. In the cyclic corrosion test results, Cl- was concentrated at the metal/rust interface in all of the steels regardless of Cr content. The Cl- was uniformly concentrated and distributed on the 0 Cr steel, but locally and non-uniformly concentrated on the Cr-added steels. The inner rust layer consisted of ß-FeOOH containing Cl- and Cr-goethite, while the outer rust layer was composed of amorphous iron oxyhydroxide mixed with various types of rust. FeCl2 and CrCl3 are formed from the Cl- nest developed in the early stage, and the pitting at CrCl3-formed regions are locally accelerated because Cr is strongly hydrolyzed to a very low pH.

7.
Materials (Basel) ; 14(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466494

RESUMO

This study investigated the optimum pickling conditions for improving the phosphatability of advanced high-strength steel (AHSS) using surface analysis and electrochemical measurements. To remove the SiO2 that forms on the surface of AHSS, 30 wt.% NH4HF2 was added to the pickling solution, resulting in a significant reduction in the amount of SiO2 remaining on the surface of the AHSS. The phosphatability was improved remarkably using HNO3 concentrations higher than 13% in the pickling solution. Furthermore, phosphate crystals became finer after pickling with a HNO3-based solution rather than a HCl-based solution. Electrochemical impedance spectroscopy (EIS) data indicated that the corrosion resistance of AHSS subjected to HNO3-based pickling was higher than that of AHSS subjected to HCl-based pickling. Fluorine compounds, which were involved in the phosphate treatment process, were only formed on the surface of steel in HNO3-based solutions. The F compounds reacted with the phosphate solution to increase the pH of the bulk solution, which greatly improved the phosphatability. The phosphatability was better under HNO3-based conditions than a HCl-based condition due to the fineness of the phosphate structure and the increased surface roughness.

8.
J Pediatr Endocrinol Metab ; 29(2): 221-5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353171

RESUMO

Diabetic ketoacidosis (DKA) is one of the precipitating factors that can evoke a thyroid storm. Thyroid storm may cause cerebral ischemia in Moyamoya disease, which can coexist in patients with Graves' disease. A 16-year-old girl complaining of dizziness and palpitations visited the emergency department and was diagnosed with DKA combined with hyperthyroidism. A thyroid storm occurred 6 h after the start of DKA management. Her Burch and Wartofsky score was 65 points. Right hemiplegia developed during the thyroid storm, and brain magnetic resonance (MR) diffusion-weighted images revealed multiple acute infarcts in both hemispheres. MR angiography showed stenosis of both distal internal carotid arteries and both M1 portions of the middle cerebral arteries, consistent with Moyamoya disease. After acute management for the thyroid storm with methimazole, Lugol solution and hydrocortisone, the patient's neurological symptoms completely resolved within 1 month, and free T4 level normalized within 2 months. Thyroid storm may trigger cerebral ischemia in Moyamoya disease and lead to rapid progression of cerebrovascular occlusive disease. As a simultaneous occurrence of DKA, thyroid storm and cerebrovascular accident in Moyamoya disease highly elevates morbidity and mortality, prompt recognition and management are critical to save the patient's life.


Assuntos
Infarto Cerebral/complicações , Cetoacidose Diabética/complicações , Doença de Moyamoya/complicações , Crise Tireóidea/complicações , Adolescente , Feminino , Humanos
9.
J Altern Complement Med ; 19(1): 50-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22950657

RESUMO

OBJECTIVES: Yin Deficiency (YD) is a pathophysiologic pattern that manifests with emaciation, dry mouth, tidal fever, Five Center Heat, night sweats, and malar flushing. The purpose of the present study was to develop and validate a new YD metric, the Yin Deficiency Scale (YDS), to define an optimum cutoff point for the YDS, and to examine the relationships between YD and Cold-Heat patterns. METHODS: A total of 169 outpatients and 83 college students were asked to complete the YDS. The college students were also asked to complete the Yin Deficiency Questionnaire (YDQ) and Cold-Heat Questionnaire (CHQ). Twelve clinicians determined whether or not the 169 outpatients had YD. YDS and YDQ data were used to estimate the internal consistency, construct validity, and concurrent validity of the YDS. CHQ data were used to examine the relationships between YDS and CHQ subscale scores. Total YDS scores and the clinicians' diagnoses of the outpatients were used to define an optimum cutoff score for the YDS. RESULTS: The 27-item YDS had satisfactory internal consistency (α=0.885) and concurrent validity, with correlations between the YDS and YDQ subscale scores. A total of eight factors were extracted in the test of construct validity, using principal component analysis, and the overall variance explained by all factors was 63.1%. Among the eight factors, cough, fever, and skin-related factors were associated only with Heat pattern, whereas pain, urine, and fatigue-related factors were associated with both Cold and Heat patterns. In the receiver operating characteristic curve analysis, the sensitivity, specificity, and area under the curve of the YDS were 73.7%, 84.8%, and 0.875, respectively. The optimum cutoff score was defined as 10 points. CONCLUSIONS: The results of this study suggest that the YDS is a reliable and valid instrument for evaluating YD.


Assuntos
Diagnóstico Diferencial , Medicina Tradicional do Leste Asiático , Deficiência da Energia Yin/diagnóstico , Adulto , Área Sob a Curva , Temperatura Baixa , Tosse , Fadiga , Feminino , Febre , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Dor , Análise de Componente Principal , Curva ROC , Valores de Referência , Sensibilidade e Especificidade , Pele , Inquéritos e Questionários , Urina , Deficiência da Energia Yin/fisiopatologia
10.
J Prev Med Public Health ; 40(1): 7-15, 2007 Jan.
Artigo em Coreano | MEDLINE | ID: mdl-17310593

RESUMO

OBJECTIVES: This study investigated the relationship of occupational class and educational background with proportional mortality ratios in Korea. METHODS: Mortality was investigated using the entire registered death data from 1993 to 2004, obtained from the Korean National Statistics Office. Proportional mortality ratios (PMRs) for specific diseases were calculated according to the occupational class and educational background of men aged 20-64. RESULTS: Manual workers were found to have higher PMRs for liver disease and traffic accidents, as did the lower educated group. Especially, this study showed trends of an increasing of the wide gap between lower and higher socioeconomic stati for liver disease, traffic accidents, diabetes mellitus and cerebral vascular disease. The mortality for cerebrovascular disease, diabetes mellitus, heart disease, traffic accident and liver disease showed increasing trends according to the calendar year for the lower than the higher social class. CONCLUSIONS: The specific conditions that had higher PMRs in the Korean lower social class were liver disease and traffic accidents. Especially, there was an increasing trend for a widening of the gap between manual and non-manual groups in relation to mortality from liver disease, diabetes mellitus and traffic accidents.


Assuntos
Causas de Morte/tendências , Escolaridade , Ocupações/classificação , Acidentes de Trânsito/mortalidade , Adulto , Transtornos Cerebrovasculares/mortalidade , Diabetes Mellitus/mortalidade , Humanos , Coreia (Geográfico)/epidemiologia , Hepatopatias/mortalidade , Masculino , Pessoa de Meia-Idade , Ocupações/estatística & dados numéricos , Razão de Chances , Fatores Socioeconômicos
11.
Bioorg Med Chem Lett ; 16(19): 5244-8, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16876404

RESUMO

Morpholin-2-one-5-carboxamide derivatives were prepared by using the one-pot Ugi multicomponent reaction and evaluated for blocking effects on T- and N-type Ca(2+) channels. Among them, compound 5i produced the highest potency (IC(50)=0.45+/-0.02 microM), while compounds 5d, 5f, 5k, 5n, 5o, and 6m produced relatively high potency as well as selectivity on T-type Ca(2+) channels. These novel scaffolds showed potent and selective T-type Ca(2+) channel blocking activities.


Assuntos
Bloqueadores dos Canais de Cálcio/síntese química , Canais de Cálcio Tipo T/efeitos dos fármacos , Morfolinas/síntese química , Morfolinas/farmacologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo N/efeitos dos fármacos , Linhagem Celular , Humanos , Concentração Inibidora 50 , Oócitos , Relação Estrutura-Atividade , Xenopus
12.
J Org Chem ; 68(1): 180-2, 2003 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-12515479

RESUMO

Olefin formation has been successfully carried out by reductive elimination reactions of halohydrins with Pd(PPh(3))(4)/In/InCl(3) in aqueous media.

13.
Mol Divers ; 6(3-4): 283-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15068092

RESUMO

A facile synthetic approach to 2,5-diketopiperazines 4 by the Ugi four-center three-component reaction using commercially available dipeptides as a bifunctional component, aldehydes, and isocyanides was described.


Assuntos
Aldeídos/química , Cianetos/química , Dipeptídeos/química , Piperazinas/síntese química , Técnicas de Química Combinatória , Dicetopiperazinas , Estrutura Molecular
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