Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros

Base de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
PhytoKeys ; 239: 205-213, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38545398

RESUMEN

Ajaniaflavida, a new species from western Sichuan and eastern Xizang, China, is described and illustrated. It is readily assigned to A.sect.Ajania owing to its straw-colored, glossy involucres and marginally whitish scarious phyllaries. Within the section, it is distinct in being a shrub of 1-2 m in height, and in having creamy yellow florets. It is superficially similar to A.ramosa in A.sect.Phaeoscyphus, but can easily be distinguished by, among other characters, the plant height, color of the florets and margins of the phyllaries. In addition, we provide a distribution map of the new species.

2.
PhytoKeys ; 238: 75-83, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38361982

RESUMEN

Ligularialushuiensis, a new species from northwestern Yunnan, China, is described and illustrated. It was tentatively placed in L.sect.Ligulariaser.Ligularia on the basis of the pinnate-palmate leaf venation, racemose synflorescence and pappus which is as long as tubular corolla. Within the series, it appeared somewhat close to both L.lamarum and L.pseudolamarum. However, L.lushuiensis can be easily distinguished from the latter two species by, among other characters, the leaf margin, bract size, involucre shape and size, and number and width of ray florets. Morphologically, L.lushuiensis is also superficially similar to L.secunda but differs readily by having distally shortly yellowish and brownish puberulent stems, palmately-pinnately veined leaves regularly dentate at margin, scarious, brown and larger bracts, and larger ray laminae. In addition, a distribution map and a diagnostic key to Chinese species of L.ser.Ligularia are also provided.

3.
Environ Res ; 248: 118420, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38316384

RESUMEN

The hydrophobic nature of an extractant is particularly critical in the treatment of wastewater. Considering that dicationic ionic liquids (DILs) are likely to be more hydrophobic, a comparative study of the separation of phenol from waters using [NTf2]- based monocationic ionic liquids (MILs) and DILs is carried out both from experimental and theoretical analysis perspectives. Experimental results revealed that DILs exhibited superior extraction ability compared to MILs, with extraction efficiencies of 93.7% and 97.4% using [BMIM][NTf2] and [C6(MIM)2][NTf2]2 as extractants, respectively. The microscopic examination through theoretical calculations elucidated the higher hydrophobicity and extraction efficiency of DILs over MILs. The results indicated that the DIL showed stronger hydrophobicity than the MIL because the hydrogen bond strength between the DIL and water was lower than that of the MIL. Although the hydrogen bond strength between the DIL and phenol was lower than that of the MIL, the stronger van der Waals forces existed between DIL and phenol, so DIL was more efficient in extracting phenol. In addition, the experimental parameters were optimized to provide basic data for application, such as mass ratio of ILs to water, extraction time and temperature, pH, and initial phenol content. Finally, the DILs were recovered using rotary evaporation apparatus, and the results demonstrated that DILs had good recovery and reuse performance. In brief, this work could provide an effective method for the treatment of phenol-containing wastewater. And the revelation of molecular mechanism is expected to positively impact the design of high-performance task-specific ILs.


Asunto(s)
Líquidos Iónicos , Líquidos Iónicos/química , Fenol , Aguas Residuales , Fenoles , Agua/química , Interacciones Hidrofóbicas e Hidrofílicas
4.
Ann Thorac Surg ; 77(6): 2066-70, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15172268

RESUMEN

BACKGROUND: Exercise intolerance of the hand after harvest of the radial artery is not well understood, although mild reductions of blood flow to the hand are reported. To ascertain its prevalence, patient symptoms implying potential exercise intolerance were evaluated by measuring transcutaneous oxygen pressure of the hand during grip exercise. For ascertaining predictive values, we verified ulnar flow reserve measured by Doppler ultrasonography before the harvest of radial artery. METHODS: Forty patients whose radial artery was harvested for coronary bypass graft, were interviewed and tested 1 year after operation, and their preoperative ultrasonographic data compared. RESULTS: Five patients (12.5%) had mild symptoms implying exercise intolerance. Exercise tests revealed severe decreases in tissue oxygenation in 7 patients (17.5%), but in accordance with symptoms (p = 0.0018). Tissue oxygenation in the operated hand was lower than in the nonoperated even in asymptomatic patients (p = 0.0011). Preoperative Doppler echography revealed that ulnar arteries of symptomatic patients were smaller (p = 0.0019) and carried lower blood flows during manual compression of the radial artery (p = 0.0004) compared with those of asymptomatic patients. Smaller ulnar arteries (less than 1.4 mm/m(2)) with poor flow reserves (less than 60 mL x min(-1) x m(-2) during radial compression) appear to indicate risks for exercise intolerance (p = 0.0004). CONCLUSIONS: More than 10% of patients after harvest of radial arteries had mild symptoms implying exercise-intolerance, which accorded with abnormal tissue oxygenation during grip exercise. Work habits of patients should be considered in radial harvest decisions, especially if preoperative Doppler echography indicates lower flow reserves for the ulnar artery.


Asunto(s)
Puente de Arteria Coronaria , Tolerancia al Ejercicio , Fuerza de la Mano , Oxígeno/sangre , Arteria Radial/trasplante , Recolección de Tejidos y Órganos/efectos adversos , Velocidad del Flujo Sanguíneo , Monitoreo de Gas Sanguíneo Transcutáneo , Femenino , Mano/irrigación sanguínea , Humanos , Isquemia/sangre , Isquemia/diagnóstico por imagen , Isquemia/etiología , Masculino , Persona de Mediana Edad , Arteria Cubital/diagnóstico por imagen , Arteria Cubital/fisiopatología , Ultrasonografía Doppler
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA