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201.
Engaging local actors in Environmental Education activities seems to be an important condition for environmental sustainability. Lack of common purpose among local and external researchers constrains the engagement. Following these insights, we implemented a participatory action research project related to tree planting as part of creating an Environmental Education programme at Ilonga Teacher Training College, surrounding primary schools and villages. The purpose of the initial phase of the project was to contextualize an action plan as a strategy to engage local actors in the change process from the beginning of the project. The research questions were: How can we engage local actors in participatory action research addressing resource constraints for EE; and what are the results of the participatory planning process? To answer these questions, we mapped environmental resources and challenges in the chosen area. Thereafter, we organized an empowerment process through Focus Group Discussions and a workshop discussing the challenges and opportunities available for successful implementation of the project. These discussions formed the foundation for creating a plan for implementing the EE project. In this paper, we present the results of the planning strategies, and discuss factors contributing to the success of the initial phase of the project. We found that stakeholders’ trust and sense of project coherence were key motivating factors for the development of a collaborative planning process and learning through initial actions.  相似文献   
202.
Chronic myeloid leukemia is a myeloproliferative disorder with a unique rearrangement, the Philadelphia chromosome. Oxidative stress, a pervasive condition of an increased number of reactive oxygen species, is now recognized to be prominent feature of various diseases and their progression. Thus antioxidants, which control the oxidative stress state, represent a major line of defense regulating overall true state of health. The relationship between antioxidants status and levels of well-known markers of oxidative stress that are measured as lipid peroxides and oxidized proteins reflect better health indices and postures. The aim of this study was to evaluate the role of oxidative stress in pathophysiology of Chronic myeloid leukemia by measuring the circulating plasma lipid peroxide levels in terms of malonyldialdehyde, total lipid hydroperoxide and oxidized proteins as protein carbonyl whereas antioxidant status were estimated in terms of reduced glutathione and total thiol in plasma of Chronic myeloid leukemia patients. The present study included 47 Chronic myeloid leukemia patients and 20 age-and sex-matched healthy subjects. Out of 47 Chronic myeloid leukemia patients, 31 were in chronic phase (CML-CP) and 16 in accelerated phase (CML-AP). The median age of Chronic myeloid leukemia patients was 33 years and that of controls was 32 years. Oxidative stress and antioxidant status in plasma were evaluated by spectrophotometric procedures. There was a significant increase (p<0.05) in plasma malonyldialdehyde, total lipid hydroperoxide and protein carbonyl levels in Chronic myeloid leukemia patients as compared to healthy subjects. Our results also showed that plasma malonyldialdehyde and protein carbonyl levels were markedly elevated (p<0.05) in both chronic phase (CML-CP) and accelerated phase (CML-AP) as compared to healthy volunteers. Antioxidant status was found to be significantly decreased (p<0.05) in Chronic myeloid leukemia patients and its phases as compared to healthy participants. It could be concluded that oxidative stress may be associated with the pathophysiology of Chronic myeloid leukemia.  相似文献   
203.
In this study, an adaptive interval type-2 Takagi-Sugeno-Kang fuzzy logic controller based on reinforcement learning (AIT2-TSK-FLC-RL) is proposed. The proposed controller consists of an actor, a critic and a reward signal. The actor is represented by the IT2-TSK-FLC in which the antecedents and the consequents are interval type-2 fuzzy sets (IT2FSs) and type-1 fuzzy sets (T1FSs), respectively, which are named A2-C1. The critic is represented by a neural network, which approximates the optimal guaranteed cost in the control design to ensure the system stability for all admissible uncertainties and noise. The use of a reward signal to formalize the idea of a goal is one of the most distinctive features of RL. Thus, the proposed controller evolves in time as a result of the online learning algorithm. The parameters of the proposed controller are learned online based on the Lyapunov theorem to guarantee the stability, overcome the shortcomings of the gradient descent, such as the local minima and instability, and determine the learning rate of the IT2-TSK-FLC controller. Furthermore, the critic stability is discussed for determining the optimal learning rate. The proposed controller is applied to uncertain nonlinear systems to show its robustness in reducing the effect of system uncertainties and external disturbances and is compared to other controllers.  相似文献   
204.
Impaired fasting glucose (IFG) is a high risk subclinical condition for the progression of type 2 diabetes mellitus and the hyperglycemia seen in this condition is because of the development of insulin resistance (IR). Obesity, inflammation, oxidative stress and many other factors have been implicated in development of IR in type 2 diabetes mellitus and its successive complications. Current study was aimed to ascertain the correlation of inflammation and oxidative stress markers [interleukin-6 (IL-6) and myeloperoxidase (MPO)] with IR in subjects with IFG. In this study, 80 subjects (40 IFG, 40 healthy controls) aged 25–45 years were selected based on their fasting plasma glucose (FPG) values and clinical history. Serum insulin, IL-6 and MPO were estimated by ELISA method and IR was calculated using Homeostatic Model Assessment Index 2 (HOMA 2) calculator. Pearson’s correlation coefficient and independent sample ‘t’ test were used for statistical analysis. IL-6 and MPO were found to be significantly elevated in IFG group and both correlates significantly with IR (r 0.413, r 0.645). Only MPO had significant correlation with FPG (r 0.388). In conclusion, the association of altered levels of IL-6 and MPO with IR are suggestive of a role of inflammation and oxidative stress in the initiation and progression of IR in individuals with IFG.  相似文献   
205.
The thirsty bird     
Z. Ahmad 《Resonance》1997,2(6):86-88
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206.
207.
A mathematical theory is developed for the nonlinear flexural response of an elastic, infinitely long, thin cylindrical shell submerged in an acoustic medium. The non- linearities examined pertain solely to the elastic field. Application of the theory is displayed in the context of a specific interaction problem. Inadequacies resulting from the use of existing interaction theories which employ a linear shell theory are displayed and critically examined.  相似文献   
208.
在国家自然科学基金和国家重点基础研究专项经费(“973”项目) 资助下,自2003年以来,中国科学院半导体研究所固态量子信息课题组在固态量子信息研究 中取得了一些新进展。本文对这些进展作一些简单介绍。  相似文献   
209.
Education and Information Technologies - Mobile-learning (M-learning) apps have grown in popularity and demand in recent years and have become a typical occurrence in modern educational systems,...  相似文献   
210.
Education and Information Technologies - The key objective of this study was to reveal the key factors that impact university students’ continued usage intentions with respect to Learning...  相似文献   
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