Orientation and electrocatalysis of riboflavin adsorbed on carbon substrate surfaces

Based on scanning tunnelling microscopy and electrochemical measurements, orientation and electrocatalytic function of riboflavin adsorbed on carbon substrates have been described for the first time. Scanning tunnelling micrographs show clearly that tip induction may result in an orientation change of the adsorbed riboflavin molecule on highly oriented pyrolytic graphite from the initially vertical orientation to the stable flat form. The adsorbed riboflavin as an effective mediator can accelerate the reduction of dioxygen which accepts two electrons from the reduced riboflavin to generate hydrogen peroxide. The rate constants of the electrocatalytic reaction in various pH solutions were determined using a rotating disc electrode modified with riboflavin. The pH effect and possible catalytic mechanism are discussed in detail.

Direct electron communication between glucose oxidase and carbon electrode covered with polypyrrole

Glucose oxidase can be effectively adsorbed onto the polypyrrole(PPy) thin film electrochemically formed on an anodized galssy carbon electrode(GCEa). Direct electron communication between the redox of GOD and the modified electrode was successfully achieved, which was detected using cyclic voltammetry. GOD entrapped in PPy film still remained its biological activity and could catalyze the oxidation of glucose. As a third generation biosensor, GOD-PPy/GCEa responded linearly up to 20 mM glucose with a wider linear concentration range.

A comparison of electrocatalytic ability of various mediators adsorbed onto paraffin impregnated graphite electrodes for oxidation of reduced nicotinamide coenzymes

Twelve mediators have been modified by adsorption onto the paraffin impregnated graphite electrodes (IGE). The resulting electrodes exhibit electrocatalytic activity of different degrees towards oxidation of 1,4-dihydronicotinamide adenine dinucleotide (NADH). The electrocatalytic ability of the chemically modified electrode (CME) depends mainly on the formal potential and molecular structure of mediator. The formation of the charge transfer complex between NADH and adsorbed mediator has been demonstrated by the experiments using a rotating disk electrode. An electrocatalytic scheme obeying Michaelis-Menten kinetics has been confirmed, and some kinetic parameters were estimated. The solution pH influences markedly the electrocatalytic activity of the modified electrode. Various possible reasons are discussed.

ELECTROCATALYTIC OXIDATION OF REDUCED NICOTINAMIDE COENZYMES AT ORGANIC DYE-MODIFIED ELECTRODES

Chemically modified electrodes (CMEs) were prepared by adsorbing different dyes, including methylene blue (MB), toluidine blue (TB) and brilliant cresyl blue (BCB), onto glassy carbon electrodes (GCE) with anodic pretreatment. The electrochemical reactions of adsorbed dyes are fairly reversible at low coverages. The CMEs are more stable in acid solutions than in alkaline ones, which is mainly due to decomposition of the dyes in the latter media. They exhibit an excellent catalytic ability for the oxidation of nicotinamide coenzymes (NADH and NADPH). The formation of a charge transfer complex between the coenzyme and the adsorbed mediator has been demonstrated using a rotating disk electrode. The charge transfer complex decomposition is a slow step in the overall electrode reaction process. Some kinetic parameters are estimated. Dependence of the electrocatalytic activity of the CMEs on the solution pH is discussed.

ORGANIC-PHASE ENZYME ELECTRODE OPERATED IN WATER-FREE SOLVENTS

A new material, polyhydroxyl cellulose, and a refrigerating immobilization method were used to construct HRP-mediator electrode for determination of hydrogen peroxide in water-free organic solvents. Rapid and sensitive response was obtained. The enzyme el

ELECTROCATALYTIC OXIDATION AND FLOW-INJECTION DETERMINATION OF REDUCED NICOTINAMIDE COENZYME AT A GLASSY-CARBON ELECTRODE MODIFIED BY A POLYMER THIN-FILM

G chemically modified electrode (CME) was prepared by electrochemical copolymerization of pyrrole and Methylene Blue. The resulting CME exhibits effective electrocatalytic activity towards the oxidation of reduced nicotinamide coenzymes (NADH and NADPH),

ELECTROCATALYTIC OXIDATION OF REDUCED NICOTINAMIDE COENZYMES AT METHYLENE GREEN-MODIFIED ELECTRODES AND FABRICATION OF AMPEROMETRIC ALCOHOL BIOSENSORS

Chemically modified electrodes with Methylene Green adsorbed on the graphite surface and incorporated into carbon paste exhibit excellent electrocatalytic ability for oxidation of NADH. Alcohol dehydrogenase, nicotinamide adenine dinucleotide (NAD+) and m

FLOW-INJECTION ANALYSIS OF MYOGLOBIN AND HEMOGLOBIN AT TOLUIDINE BLUE CHEMICALLY MODIFIED ELECTRODE

Electrodeposition of the phenothiazine mediator titrant toluidine blue onto a glassy carbon substrate at an appropriate potential was used to construct a toluidine blue chemically modified electrode (CME) exhibiting electrocatalytic reduction for myoglobin and hemoglobin. The CME catalyzed the hemoprotein electroreduction at the reduction potential of the mediator molecule. When the CME as used as a detector for flow injection analysis at a constant applied potential of -0.30 V vs. a saturated calomel electrode, it gave detection limits of 20 and 50 ng (1.2 and 0.78 pmol) injected myoglobin and hemoglobin, respectively, with a dynamic linear concentration range over 2 orders of magnitude. After a brief equilibration period, the CME retained nearly 90% of its initial myoglobin response over 8 hours of continuous exposure to the flow-through system.

成就目标与心理健康的关系及相关因素的作用

The relationship between achievement goal and mental health, and the effect of the related factors Abstract Recently, adolescent’s mental health and depression problem have been widely concerned all over the world. Studies concerning it have been done from different perspectives. High school is the key period of adolescent’s physical and mental development, when they may have a high risk of mental conflicts, certain behavioral and emotional problems. Through questionnaire with high school students as subjects, this study examines achievement goal, self-concept, social comparison and the relationship between these factors and mental health. This study consists of three parts: 1) a preliminary exploration of the relationship between vocational school students’ achievement goal, self-concept and their mental health; 2) a revision of the simplified Chinese version for Dykman’ s goal Orientation Inventory; 3) a further discussion on the relationship between high school students’ achievement goal, self-concept, social comparison and depression. Major findings of this study are: 1. Dykman’s Goal Orientation Inventory is revised. This revised version, with high validity and reliability, conforms to Dykman’s theoretical assumptions and can be a convenient and effective measurement for achievement goal. 2. Self-concept and achievement goal of vocational school students can make a significant prediction of their mental health. Learning goal influences mental health through self-concept. 3. Achievement goal, self-concept and social comparison of high school students are closely related to their depression. 4. Self-concept and social comparison of high school students are the mediator variable between achievement goal and depression. The theoretical and practical implications of this study: 1. With the simplified Chinese version of Dykman’s Goal Orientation Inventory revised and used first in this study, its applicability is inspected and the conclusion drawn by Dykman on the prediction of achievement goal on depression is examined as well; on the basis of previous studies, a comprehensive and systematic study is done on how the factors work together to influence mental health(particularly depression). 2. This study enrichs the studies with high school students as subjects. It provides methods and basis for the theoretical studies and interference about high school students’ mental health education and depression problem.

我国部分地区中学生的学校回避倾向研究

The aim of this research is to explore the relationships between school avoidance tendency and school stressors, stress response, social support, coping style of secondary school students. Three studies were carried out. School avoidance tendency scale, mental health scale, coping style scale of secondary school students from Japan were revised in the first research. In the second research, the difference in gender, cities, grades of five variables were discussed. In the third research, the relationships of five variables were discussed. A total of 883 students from grade one of middle school to grade 3 of high school in Beijing, Taiyuan and Wulanchabu, completed three scales. Analysis showed that: 1. The main effects of city, gender, and grade were present significantly on School avoidance tendency, and the inter-effects were not significant. The differences were significant between three grades of middle schools, and not significant between three grades of high schools. The high school students were significant than middle school students on school avoidance tendency. 2. The main effect of city was not significant, but gender, and grade were present significantly on stressor, and the inter-effects were not significant. The most stressor was study one, than the relationship stressor from teachers. The relationship stressor from friends was at least. 3. The main effects of city and grade were present significantly on stress responses, but the main effect of gender was not significant, and the inter-effect was not significant. The most stress response was the physical response. 4. The main effects of city and gender, the inter-effect were not present significantly on social supports. The main effect of grade was present significantly. The most social support was from mother, than from friends, father, and the teachers. 5. The differences between cites on coping styles were not significant. Positive coping style was used mostly, than the style of help requirement, cognitive coping style. 6. Stressor and stress responses had significant positive predictive role on school avoidance tendency. Social supports had negative predictive role. Social supports had not moderator role between stressor, stress responses and schools avoidance tendency. Stress responses had a part of mediator between stressor and school avoidance tendency. 7. In the coping styles, positive coping style and help requirement style had negative predictive role, but cognitive coping style had positive predictive role on school avoidance tendency. Coping styles had negative predictive role. Coping styles had not moderator role between stressor, stress responses and school avoidance tendency.

小学学习不良儿童对言语交际策略的理解与运用

[Abstract] Verbal communication strategy (VCS) refers to a programmed knowledge applied by individuals to understand and express intentions via language symbols in their realization of communicative objectives according to social conventions. As an important index of social development, verbal communication strategy has provided a new perspective for social skill studies. However, more work has to be done in the investigation of LD children’s VCS developmental pattern and affecting mechanism. Through contextual test, structured interview and role-play, the present study, by adopting integrated measurements of instrumental and interpersonal effectiveness, explored the developmental characteristics of Chinese learning-disabled primary school children across 3-6th grades at both comprehension and application levels. Then, their social perspective-taking performance and verbal retelling competence of each participant were examined, on the basis of which, path analysis was conducted, with social perspective-taking, verbal retelling and verbal communication strategy comprehension as independent variables, to reveal the inner mechanism affecting LD children’s application of verbal communication strategy. Finally, an intervention study was carried out through a combination of polite request strategy understanding lessons and social perspective-taking training dramas. The results indicate that:(1) No significant grade differences were found in LD group for polite request strategy, while significant differences were reported across different grades of non-LD children. For indirect reply strategy, significant grade and gender differences were found among LD children, but the developmental trajectory between the two groups was different. For both polite request and indirect reply strategies, the strategy comprehension level of LD children was significantly lower than those without learning disabilities. (2) No significant grade and gender differences were found in LD group in their application of polite request strategy, while for non-LD children, significant differences were reported across different grades. For indirect reply strategy, both LD and non-LD groups exhibited similar developmental characteristics. Significant group differences only exist in the over-all application level of polite request strategies, not in indirect reply strategies. However, the differences of the latter between the two groups were found at significant level only among the 11-12 year olds. (3) LD children’s perspective-taking and verbal retelling competence were significantly lower than those of non-LD group. For polite request strategy, the influence of social perspective-taking to strategy application was indirect and must be via strategy comprehension, while for indirect reply strategy, strategy comprehension was found to play as a partial mediator between social perspective-taking and strategy application. The influence of verbal retelling to strategy application was indirect on both types of strategies. (4) LD children’s strategy comprehension and social perspective-taking level can be improved, and the improvement of these two competences has significant positive impact on the increase of their strategy application level. Key Words: learning disabilities, verbal communication strategy, social perspective- taking

道德强度对企业道德决策的影响及作用机制

Moral decision-making in business means the decisions involved in moral issues in business context. Moral intensity is a construct that captures the extent of issue-related moral imperative in a situation, which is one of the most important factors in the study of moral decision-making in business. Based on Issue-Contingent Model, the present study investigated the influence of moral intensity on moral decision-making in business (including moral recognition, moral judgment, and moral intent in the present study), and further focused on exploring the mechanism of moral intensity in moral decision-making in business. Recently, the studies in decision-making gave more emphasis to the role of emotions. The present study tried to include empathy into moral decision-making in business to explore the role of empathy in the relationship between moral intensity and moral decision-making in business, which would enrich and extend Issue-Contingent Model. The present study would also make up for a deficiency in the study of moral decision-making in business that overemphasized the rational reasoning and neglected the role of emotions. There were three parts in the present study. Firstly, study 1 replicated the former study and explored the relationship between perceived moral intensity and moral decision-making in business in China by questionnaire method. Secondly, study 2 focused on exploring the influence of the components of moral intensity on moral decision-making in business and empathic response by experimental method. Finally, study 3 explored the role of empathy in the relationship between moral intensity and moral decision-making in business. The results indicated that, 1.Perceived moral intensity was the significant predictor for moral decision- making in business. 2.Magnitude of consequence, social consensus, and probability of effect had significant effects on moral decision-making in business. Magnitude of consequence and probability of effect could influence empathic response significantly. 3.Empathic response played the role of mediator between moral intensity and moral decision-making in business. Empathic response completely mediated the relationship between moral intensity and moral recognition. Empathic response partly mediated the relationship between moral intensity and moral judgment, moral intent. Further analysis indicated that probability of effect and magnitude of consequence relied more on empathic response than social consensus to influence moral judgment and moral intent. Dispositional empathy could influence moral decision-making in business through perceived moral intensity and empathic response. 4.Controlled empathic levels could influence moral decision-making in business significantly. Empathic levels influenced the effect of probability of effect on moral decision-making in business, and did not influence the effect of magnitude of consequence and social consensus on moral decision-making in business. These findings not only contribute to enrich the models of moral decision- making in business, but also have significant practical applications in the training of moral decision-making in business.

消费者特征对其网络购物态度和行为意向的影响

In recent years, global online shopping grows rapidly, China's growth rate is far greater than the average level of the world. Online shopping as a new type of shopping patterns gradually drew the researcher's attention. There were so many existing researches on the relationship between consumer characteristic and online shopping attitude and intention, but few togethered the different abstract levels of consumer characteristic in one research. In this study, 3M Model was introduced as theory guide of whole research work, the Chinese consumers who knew about the online shopping was the research object, questionnaire survey was used to collect the data, different abstract levels of consumer characteristic were togethered in a hierarchical model, tried to establish a model to explain the relationship between different abstract levels of consumer characteristic and online shopping attitude and intention. In addition, the study also compared the models posed by data from different consumer groups. The results showed that: First, consumers’ openness, need for arousal, assessment of online shopping experience, perceived risk of online shopping would affect their online shopping attitude and online shopping intention. Second, openness, need for arousal indirectly influenced the online shopping intention through the perceived risk of online shopping. Third, the perceived risk of online shopping indirectly influenced the online shopping intention through online shopping attitude. Fourth, assessment of online shopping experience indirectly influenced the online shopping intention through the perceived risk of online shopping and online shopping attitude. Fifth, only online shopping attitude would directly affect online shopping intention. It also worked as a mediator variable in the final model. Sixth, network age, risk propensity did not significantly affect the online shopping attitude and online shopping intention. Seventh, freight fluctuation can affect student more than in-service on online shopping intention.

保险推销员自我效能感及其工作模型

The research studied self-efficacy and job mechanism of insurance salesmen in China by the methods of in-depth interview, focus-group, semi-open questionnaire, standard questionnaire. There were about 1300 samples surveyed. The way of data analysis such as factor analysis, correlation analysis, regreesion analysis and structure equation was used. Four following conclusions were drawn: First, self-efficacy of inssurance salesmen in China consists of eight factorswhich are interview skills, manner, persistence, control of emotion, plans and comments, master of knowledge, intuition and judgement, preparation. Second, the relationship between self-efficacy and other job variables such as achievement motivation, work incentive, coping strategy, view of ability, performance, goalsetting, colleague relationship, the way of feedback from leader, job satisfaction and exertion were tested and all the correlations were significant. Third, regression analysis was used to test the relationship between self-efficacy and the antecedent variables. The result was that four antecedent varialbes enter equation (p<.05). They are self-oriented achievement motivation, stability of emotion, performance and colleague relationship.. Finally, vertified by path-analysis, the research posits a comprehensive model about job for insurance salesmen, in which self-efficacy was the most important factor. On the one hand, self-efficacy has dominant effects on the consequent variables, such as mastery goal, performance- approach goal, job satisfaction, exertion, coping strategy, on the another hand, self-efficacy was found as mediator of the relationship between the antecedent variables and consequent variables.

STAT1 – główny czynnik regulatorowy w zapaleniu i dysfunkcji naczyniowej

Wydział Biologii: Instytut Biologii Molekularnej i Biotechnologii