Abstract Background: Cyclocodon lancifolius (Roxb.) Kurz is a perennial medicinal and edible plant with a huge potential economic value. The wild resources of this plant are gradually scarce by the serious destruction of the habitat and the limitations of sexual reproduction. This is the first attempt to establish an in vitro reproductive system for the species. Hypothesis: The suitable plant regulator types and its mass concentration range, combined with the explants, can induce the development of plants at various stages. We expected to establish an in vitro regeneration system of C. lancifolius based on these factors. Species studied: Cyclocodon lancifolius Study site and years of study: Yunnan Breeding and Cultivation Research and Development Center of Endangered and Daodi Chinese Medicinal Materials, Yunnan University of Chinese Medicine, from 2017 to 2019. Methods: The plant regeneration of C. lancifolius was established by single factor, L9 (34) orthogonal and complete combination experiments. Results: Stem segments were the best explants for callus induction on MS medium containing 0.05 mg·L-1 KT, 0.5 mg·L-1 6-BA and 0.5 mg·L-1 NAA. MS medium with 0.2 mg·L-1 TDZ and MS medium were used alternately as the culture method to conduct differentiation and proliferation of adventitious shoot. The optimal protocol for the rooting was MS medium combined with 0.1 mg·L-1 6-BA and 1.0 mg·L-1 NAA. Conclusions: A rapid propagation system of C. lancifolius was established which provided a possible solution for the protection of wild resources and artificial cultivation.

Resumen Antecedentes: Cyclocodon lancifolius es una planta perenne medicinal y comestible. Los recursos silvestres de esta planta escasean gradualmente debido a la grave destrucción del hábitat y las limitaciones de la reproducción. Este es el primer intento de establecer un sistema reproductivo in vitro para esta especie. Hipótesis: El tipo de regulador de crecimiento adecuado y su rango de concentración másica, combinado con los explantes, pueden inducir el crecimiento de plantas en varias etapas. Se espera establecer un sistema de regeneración in vitro de C. lancifolius basado en estos factores. Especie estudiadas: Cyclocodon lancifolius. Sitio y años del estudio: Universidad de Medicina China de Yunnan, De 2017 a 2019. Métodos: La regeneración de plantas de C. lancifolius se estableció mediante los experimentos de un solo factor, ortogonales de tipo L9 (34) y los de combinación completa. Resultados: Los segmentos del tallo fueron los mejores explantes para la inducción de callos en un medio MS que contenía 0.05 mg·L-1 KT, 0.5 mg·L-1 6-BA y 0.5 mg·L-1 NAA. El medio MS + 0.2 mg·L-1 TDZ se usó de manera alternativa con el medio MS como el método de cultivo para realizar la diferenciación y proliferación de brotes adventicios. El protocolo óptimo para el enraizamiento fue el medio MS combinado con 0.1 mg·L-1 6-BA y 1.0 mg·L-1 NAA. Conclusiones: Se estableció un sistema de propagación rápida de C. Lancifolius que proporcionó una posible solución para la protección de los recursos silvestres, así como para el cultivo artificial.

ABSTRACT PURPOSE: To determine whether Toll-like receptor 7 (TLR7) is the potential targets of prevention or progression in the renal ischemia/reperfusion (I/R) injury of STZ-induced diabetic rats. METHODS: Thirty six Sprague-Dawley rats were randomly arranged to the nondiabetic (ND) or diabetic group (DM), with each group further divided into sham (no I/R injury), I/R (ischemia-reperfusion) and CD (given by Chloroquine) group. Preoperatively, Chloroquine (40 mg/kg, intraperitoneal injection.) was administrated 6 days for treatment group. I/R animals were subjected to 25 min of bilateral renal ischemia. Renal function, histology, apoptosis, cytokines, expression of TLR7, MyD88 and NF-κB were detected. RESULTS: The serum levels of blood urea nitrogen, creatinine, IL-6 and TNF-α, apoptotic tubular epithelial cells, expression of TLR7, MyD88 and NF-κB were significantly increased in DM+I/R group, compared with ND+I/R group (p<0.05). All these changes were further improved by TLR7 inhibition Chloroquine except Paller scores (p<0.05). CONCLUSION: Toll-like receptor 7 inhibition attenuates the acute renal ischemia/reperfusion injury of STZ-induced diabetic in SD rats.

A sensitive and stable electrochemical sensor based on polyaniline/graphene-ferrocenecarboxylic acid (PANI/GR-FCA) composite film modified glass carbon electrode for determination of nitrite was presented and its morphology and structure were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques were used to investigate the electrochemical behavior of the nitrite oxidation, which exhibited an enhanced voltammetric response at the modified electrode. In the optimal condition, the oxidation of nitrite in Britton-Robinson buffer solution (BR) of pH 4.0 had the higher peak current than the bare electrode. A linear calibration curve over the concentration range 0.4-300 µmol L-1 of nitrite were obtained with a linear regression equation I (µA) = 0.1589 + 0.0020C (µmol L-1) (R = 0.9991, n = 13) and the detection limit was down to 0.02 mmol L-1 (S/N = 3). The recoveries of all determinations ranged between 96-102%. At the same time, the modified electrode showed a good long-term stability and reproducibility for determination of nitrite, as well as high selectivity.

In order to assess the role of bromination reaction in the oxalic acid-acetone-KBrO3-Ce(IV)-H2SO4 oscillating system, both the effects of oxalic acid and acetone were studied in detail. Based on the experimental data, we propose a new skeleton scheme containing 11 reactions to simulate the oscillating behavior of the system, in which the bromination reaction between acetone and bromine should be considered as another source of Br−.

Se estudian en detalle los efectos del ácido oxálico y de la acetona en la reacción ácido oxálico-acetona-KBrO3-Ce(IV)-H2SO4 con el fin de evaluar el papel de la reacción de bromación el sistema oscilante. Basados en los datos experimentales, proponemos un nuevo esquema que contiene a 11 reacciones para simular el comportamiento oscilante del sistema en el que la reacción de bromación entre acetona y bromo debe ser considerada como otra fuente de Br−.

Based on a ten-step chemical model involving the concentrations of I2(aq), O2(aq), and the intermediates of I- and HIO2, four independent variables and seven irreversible steps, the nonlinear behavior of Bray-Liebhafsky (BL) oscillating reaction was investigated. The results showed that with different values of initial concentrations of reactants in the process of simulation, both periodic oscillation and chaotic behavior could be observed. In addition, at the same initial concentrations and rate constants, the system becomes more and more regular after being chaos. That is to say, the translation from chaos to periodic oscillation at the same initial conditions appeared in the BL system. The nonlinear behavior of system was also investigated briefly.

En base a un modelo químico de diez pasos que involucra las concentraciones de I2 (ac), O2 (ac), los intermediarios de I- y HIO2, cuatro variables independientes y siete pasos irreversibles, fue investigado el comportamiento no lineal de la reacción oscilatoria de Bray-Liebhafsky (BL). Los resultados mostraron que con valores diferentes de concentraciones iniciales de los reactantes en el proceso de simulación, tanto la oscilación periódica como el comportamiento caótico pudieron ser observados. Además, a la misma concentración inicial y constantes de velocidad, el sistema se convierte en más regular a partir del caos. Es decir, la traslación del caos a la oscilación regular en las mismas condiciones iniciales aparece en la Reacción BL. El comportamiento no lineal del sistema también fue estudiado resumidamente.

Através da técnica de polimerização radicalar por transferência atômica (ATRP) foram preparadas novos polímeros tipo pente com molhabilidade ajustável (líquido iônico) de hexafluorfosfato poli[2-(1-butilimidazolino-3-ila)etila metacrilato (PBIMH-PF6-), a partir de um substrato bruto modificado com uma camada iniciadora composta de brometo 2-bromoisobutirila. Várias técnicas de caracterização como elipsometria, medidas de ângulo de contato estático, espectroscopia fotoeletrônica de raios X (XPS) e microscopia de força atômica (AFM) foram utilizadas para caracterizar os filmes em cada etapa de modificação da superfície. Estudos cinéticos revelaram um aumento linear na espessura do filme polimérico em função do tempo de reação, indicando que o crescimento da cadeia a partir da superfície, é um processo cujo controle apresenta características de polimerização "viva". As medidas de molhabilidade indicaram que as interações de troca iônica podem ser usadas para alterar as características da superfície de hidrofilicidade para hidrofobicidade de forma reversível. O substrato bruto obtido por ataque químico exibiu uma melhor hidrofobicidade quando comparado à superfície lisa do substrato plano modificado com as mesmas cadeias poliméricas tipo pente (líquido iônico).

Using surface initiated atom transfer radical polymerization (ATRP), novel tunable wettability polymer (ionic liquid) brushes poly[2-(1-butylimidazolium-3-yl)ethyl methacrylate hexafluorophosphate] (PBIMH-PF6-) from a rough substrate modified with an initiator layer composed of 2-bromoisobutyryl bromide was prepared. Various characterization techniques including ellipsometry, static water contact angle measurements, X-ray photoelectron spectroscopy (XPS), and atomic force microscope (AFM) were used to characterize the films for each surface modification step. Kinetic studies revealed a linear increase in polymer film thickness with reaction time, indicating that chain growth from the surface was a controlled process with a "living" characteristic. Wetting measurements indicated that ion exchanging interactions can be used to switch surface characteristics from hydrophilicity to hydrophobicity in a reversible manner. Compared with the smooth surface of the flat substrate modified with the same polymer (ionic liquid) brushes, the rough substrate by chemical etching exhibited better hydrophobicity.

Foi proposto um procedimento para a determinação de para-fenilenodiamina (PPD) em águas residuais, baseada na perturbação de uma reação oscilante em uma situação fora do equilíbrio, próximo a uma bifurcação pela reação Belousov-Zhabotinskii (B-Z), uma vez que este ponto encontra-se muito sensível → perturbação pela mudança de vizinhança. Os resultados indicam que a variação de potencial (ΔE) é linearmente proporcional ao antilogarítmo da concentração de PPD, (-logC), no intervalo de concentração correspondente a 4,68 × 10-7 - 1,95 × 10-5 mol L-1 (r = 0,9981) e com limite de determinação (LOD) de 9,50 × 10-8 mol L-1. Uma boa recuperação do analito foi obtida, em um intervalo de aproximadamente 95,1 a 102,3%.

A convenient method for determination of p-phenylenediamine (PPD) in wastewater has proposed, based on the perturbation of a non-equilibrium stationary state near a bifurcation for the Belousov-Zhabotinskii (B-Z) reaction, due to this point being very sensitive to the surrounding change. Results indicate that the change of the potential (ΔE) is linearly proportional to the negative logarithm concentration of PPD (-logC) in the range of 4.68 × 10-7 - 1.95 × 10-5 mol L-1 (r = 0.9981) with a limit of detection (LOD) of 9.50 × 10-8 mol L-1. A good recovery was obtained at ca. 95.1 to 102.3%.

Foi proposto um procedimento conveniente por meio de um sistema químico oscilante como uma ferramenta analítica para a determinação de ácido L-aspártico (L-Asp). O sistema envolve a reação entre peróxido de hidrogênio e tiocianato de sódio, catalizada por íons Cu(II) em meio alcalino. O método baseia-se na relação linear entre as mudanças no período de oscilação e o logarítmo da concentração de ácido L-aspártico. Condições otimizadas foram posteriormente validadas para garantir a confiabilidade do método. Sob condições otimizadas, o gráfico de calibração é linear e proporcional à concentração do ácido L-aspártico no intervalo de 1,17 × 10-5 mol L-1 a 7,10 × 10-8 mol L-1 com um coeficiente de regressão linear de 0,9990 e RSD de 2,75%. O limite de determinação (LOD) foi de 5,58 x 10-8 mol L-1. O método proposto foi empregado na determinação do ácido L-aspártico em amostras de medicamentos. Além disto, a técnica HPLC foi empregada para confirmar os resultados.

A convenient procedure by means of oscillating chemical system as an analytical tool to determine the L-aspartic acid (L-Asp) is proposed. The system involves the Cu(II)-catalyzed reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium. The method relies on the linear relationship between the changes in the oscillation period and the logarithm of concentration of L-aspartic acid. Optimized conditions were further validated to ensure the reliability of the method. Under optimum conditions, the calibration plot is linearly proportional to the concentration of L-aspartic acid over the range from 1.17 × 10-5 mol L-1 to 7.10 × 10-8 mol L-1 with a corresponding regression coefficient of 0.9990 (RSD 2.75%). A lower limit of determination (LOD) was 5.58 × 10-8 mol L-1. The proposed method has been used to determine L-aspartic acid in drug sample. Additionally, the HPLC technique was also used to confirm the determination results.

The Bray-Liebhafsky reaction exhibits different nonlinear behaviors during the iodate catalyzed decomposition of acidic hydrogen peroxide in the different conditions. Both the chaotic and regular oscillations were observed. The largest Lyapunov exponent (λL), the power spectram and the log(P)-log(f) dependence for power spectram were used to evalúate these nonlinear behaviors. The effect of initial concentration of reactants on the types of oscillations and the initial potential (E o) were discussed in detail. The possible mechanism of the Bray-Liebhafsky reaction was also approached in this work

A rapid, simple and reliable method was devised for separation and determination of six metal cations, based on the capillary zone electrophoresis. The results showed that the complete separation of K+,Cu2+, Zn2+, Mn2+, Pb2+and Cd2+canbe achieved within 5 min. Anew electrolyte system containing 15 mmol-L"¹ imidazole as a background absorbance reference and 8 mmol-L"¹ malonic acid, 2 mmol-L-1 18-crown-6 ether as the complexing agents, 10%methanol as anorganic modifier, by using acetic acid to adjust the pH=4.40 was developed. The applied voltage was 20 kV at 25 °C. Under the optimum conditions, 6 ions were separated and determined with the correlation coefficient of 0.9984-0.9993. The detection limits (S/N=3) from 0.05 (K+)to 0.75 (Zn^mg-L¹. The repeatability of migration times was less than 0.60% and of peak area ranged from 3.4 to 5.6% (n=6). The results were compared with AAS for analyzing the real samples of waste-water and snow water

The computational simulation of the Bray-Liebhafsky (BL) oscillating chemical reaction by differential kinetic methodology is carried out in this work. According to the mechanism of Treindl and Noyes involving 10 reaction steps, the changes of the concentrations of I2 and O2 in solution are simulated. When the control parameters are α = 0.55, β = 0.2882 and δ < 0.6, the differential equations present periodic solution, and the oscillations can be observed in 150 min. If α, β and δ are taken as the control parameters, respectively, the bifurcation points would be observed in the processes of control parameters, changing successively with the critical values of α = 0.55, β = 0.2882, and δ = 0.6. The acidity of solution on the nonlinear phenomena is also investigated in detail.

Both the perturbation of ribavirin and the effect of variables on the proposed chemical oscillating system were studies in detail. When the sample was injected, the change of amplitude is linearly proportional to the concentration of ribavirin in the range of 1.5×10-7-6.3×10-5 mol·L-1, with a detection limit of 3.20×10-8 mol·L-1 (RSD=0.9964, N=10). In addition, a possible mechanism of the perturbation of ribavirin on the oscillating reaction was also discussed

Este estudo descreve o movimento oscilatório de uma interface água/óleo em um sistema em que a fase óleo era composta por uma mistura de nitrobenzeno, ácido pícrico e etanol, enquanto a fase aquosa era composta por uma solução de CTAB (brometo de cetiltrimetilamônio). A interface apresentava diferentes tipos de movimentos como aleatório, ondulatório e tipo gangorra, que eram afetados por condições experimentais como a concentração dos reagentes e a geometria do vaso de reação. Um mecanismo é proposto para explicar estes movimentos oscilatórios.

A macroscopic interface self-motion appearing on an oil/water liquid membrane was clearly observed. The oil phase was a mixture solution containing nitrobenzene, picric acid and ethanol, whereas the aqueous phase was a solution of CTAB (cetyltrimethylammonium bromide). The interface displayed different types of motion, such as random, wave-like motion and teeterboard-like motions, which were affected by experimental conditions like concentration of reactants and geometry of the reaction vessel. A possible mechanism to explain these motions was also proposed.

Este trabalho trata da aplicação do sistema químico oscilante B-Z catalisado por cério, na determinação do íon índio em solução aquosa, baseada na sua perturbação linear sobre o período oscilante. Os resultados mostraram que a alteração no período oscilante é linearmente proporcional à concentração do íon índio, no intervalo de 4,98×10-7 a 3,85×10-6 mol L-1, com coeficiente de correlação de 0,9984 e limite de detecção de 4,96×10-7 mol L-1, sob condições ótimas. Vários fatores influentes na determinação foram também examinados e o mecanismo de determinação foi discutido.

The present paper deals with the application of cerium-catalyzed B-Z oscillating chemical system to the determination of indium ion in aqueous solution based on its linear perturbation on the oscillating period. Results showed that the change in the oscillating period is linearly proportional to the concentration of indium ion in the range from 4.98×10-7 to 3.85×10-6 mol L-1, with a correlation coefficient of 0.9984 and a detection limit of 4.96×10-7 mol L-1 under the optimum conditions. Various influencing factors on the determination were also examined and the determination mechanism was discussed.