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971.
Toward an Eco-justice Pedagogy 总被引:1,自引:0,他引:1
C. A. Bowers 《Environmental Education Research》2002,8(1):21-34
This paper will address three issues: (1) the nature and importance of an eco-justice pedagogy; (2) how an eco-justice pedagogy differs from the recommendations of critical pedagogy theorists who rely upon key root metaphors (e.g. emancipated individualism, linear view of progress, anthropocentrism) that co-evolved with the Industrial Revolution and are now the basis of the globalization process; and (3) the reforms that need to be undertaken in teacher education in order for teachers to balance critical inquiry with helping students recognize and participate in the non-commodified aspects of community life. The latter will involve giving special attention to what teachers need to understand about how the language of the curriculum is based on root metaphors that organize thinking in ways that ignore environmental racism and the marginalization of different cultural approaches to community not oriented toward dependency upon modern technology and consumerism. 相似文献
972.
Recently direct optimization of information retrieval (IR) measures has become a new trend in learning to rank. In this paper,
we propose a general framework for direct optimization of IR measures, which enjoys several theoretical advantages. The general
framework, which can be used to optimize most IR measures, addresses the task by approximating the IR measures and optimizing
the approximated surrogate functions. Theoretical analysis shows that a high approximation accuracy can be achieved by the
framework. We take average precision (AP) and normalized discounted cumulated gains (NDCG) as examples to demonstrate how
to realize the proposed framework. Experiments on benchmark datasets show that the algorithms deduced from our framework are
very effective when compared to existing methods. The empirical results also agree well with the theoretical results obtained
in the paper. 相似文献
973.
974.
India seems to have the highest prevalence of osteoporosis. With growing awareness of osteoporosis and its impact on life
span especially in India, special attention is being paid to early detection, management and treatment of postmenopausal osteoporosis
in women. Measurement of BMD and osteocalcin are of value in estimating bone turnover rates. The aim of this study is (1)
to measure the specific, sensitive bone formation marker such as osteocalcin and BMD in postmenopausal osteoporosis women
and postmenopausal non-osteoporosis women; (2) the follow up study to evaluate the impact of specific antiresorptive therapy
(alendronate + calcium + vitamin D) regimen in postmenopausal osteoporosis by assaying osteocalcin and BMD. Sixty clinically
diagnosed postmenopausal osteoporosis patients and 60 normal subjects (postmenopausal non-osteoporosis women) were recruited
as control. Mean bone mineral density T score and Z score was significantly decreased (P < 0.001) in postmenopausal osteoporosis patients as compared to controls. Highly significant increase in the mean score of
BMD—T score and Z score from baseline to post therapy of 3 months was observed in postmenopausal osteoporosis women. Serum osteocalcin levels
were significantly increased (P < 0.001) as compared to control group. Serum osteocalcin levels were decreased significantly (P < 0.001) from baseline to post therapy of 3 months in postmenopausal osteoporosis women. BMD is the best quantifiable predictor
of osteoporotic fracture and osteocalcin is specific, sensitive, promising, currently used marker for better prognosis of
osteoporosis and for monitoring responses to antiresorptive therapy. 相似文献
975.
利用双标图分析基因型和环境交互作用 总被引:28,自引:0,他引:28
在作物的品种区域化试验中,品种的基因型和环境(G×E)交互作用越来越受到重视.一种新的非常有效的分析G×E交互作用模型是加性主效应和乘积交互作用模型(简称AMMI模型),而双标图(biplot)是解释AMMI分析结果的一种直观有效的图形工具.本文对AMMI模型及双标图作一扼要介绍,并选用1995年南方水稻区试单季晚粳组数据作为实例,给出了两种新的双标图,以帮助我们更深入地了解G×E交互作用. 相似文献
976.
Induction of diabetes by Streptozotocin in rats 总被引:1,自引:0,他引:1
A. Akbarzadeh D. Norouzian M. R. Mehrabi Sh. Jamshidi A. Farhangi A. Allah Verdi S. M. A. Mofidian B. Lame Rad 《Indian journal of clinical biochemistry : IJCB》2007,22(2):60-64
The objective of this study is to induce experimental diabetes mellitus by Streptozotocin in normal adult Wistar rats via
comparison of changes in body weight, consumption of food and water, volume of urine and levels of glucose, insulin and C-peptide
in serum, between normal and diabetic rats. Intra-venous injection of 60mg/kg dose of Streptozotocin in adult wistar rats,
makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes mellitus
in the 2–4 days. Induction of experimental diabetes mellitus is indeed the first step in the plan of purification of pancreatic
Langerhans islet cells of normal rats for transplanting under the testis subcutaneous of experimentally induced diabetic rats.
Streptozotocin induces one type of diabetes which is similar to diabetes mellitus with non-ketosis hyperglycemia in some animal
species. For induction of experimental diabetes in male adult rats weighted 250–300 grams (75–90 days), 60mg/kg of Streptozotocin
was injected intravenously. Three days after degeneration of beta cells, diabetes was induced in all animals. The diabetic
and normal animals were kept in the metabolic cages separately and their body weight, consumption of food and water, urine
volume, the levels of serum glucose, insulin and C-peptide quantities in all animals were measured and then these quantities
were compared. For a microscopic study of degeneration of Langerhans islet beta cells of diabetic rats, sampling from pancreas
tissue of diabetic and normal rats, staining and comparison between them, were done. Induction of diabetes with Streptozotocin
decreases Nicotinamide-adenine dinucleotide (NAD) in pancreas islet beta cells and causes histopathological effects in beta
cells which probably intermediates induction of diabetes. In this study, we used Streptozotocin for our experiments in induction
of experimental diabetes mellitus. After Induction of diabetes, consumption of food and water, volume of urine and glucose
increased in the diabetic animals in comparison with normal animals, but the weight of body and the volume of insulin and
C-peptide decreased in the diabetic animals. Sampling and staining of pancreas tissue of diabetic and normal rats showed that
the Langerhans islet beta cells of diabetic rats have been clearly degenerated. In three days, Streptozotocin makes pancreas
swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes. It also changes normal
metabolism in diabetic rats in comparison with normal rats. Consumption of water and food, volume of urine, serum glucose
increases in diabetic animals in comparison with normal rats but the levels of serum insulin, C-peptide and body weight decreases. 相似文献
977.
Soumela Atmatzidou Stavros Demetriadis Panagiota Nika 《Journal of Science Education and Technology》2018,27(1):70-85
Educational robotics (ER) is an innovative learning tool that offers students opportunities to develop higher-order thinking skills. This study investigates the development of students’ metacognitive (MC) and problem-solving (PS) skills in the context of ER activities, implementing different modes of guidance in two student groups (11–12 years old, N1 = 30, and 15-16 years old, N2 = 22). The students of each age group were involved in an 18-h group-based activity after being randomly distributed in two conditions: “minimal” (with minimal MC and PS guidance) and “strong” (with strong MC and PS guidance). Evaluations were based on the Metacognitive Awareness Inventory measuring students’ metacognitive awareness and on a think-aloud protocol asking students to describe the process they would follow to solve a certain robot-programming task. The results suggest that (a) strong guidance in solving problems can have a positive impact on students’ MC and PS skills and (b) students reach eventually the same level of MC and PS skills development independently of their age and gender. 相似文献
978.
In this paper, we consider theories about processes of visual perception and perception-based knowledge representation (VPR)
in order to explain difficulties encountered in figural processing in junior high school geometry tasks. In order to analyze
such difficulties, we take advantage of the following perspectives of VPR: (1) Perceptual organization: Gestalt principles,
(2) recognition: bottom-up and top-down processing; and (3) representation of perception-based knowledge: verbal vs. pictorial
representation, mental images and hierarchical structure of images. Examples given in the paper were mostly taken from Gal's
study (2005) which aimed at identifying and analyzing Problematic Learning Situations (after Gal & Linchevski, 2000) in junior high school geometry classes. Gal's study (2005) suggests that while this theoretical perspective became part of teachers' pedagogic content knowledge, the teachers were
aware of their students' thinking processes and their ability to analyze and cope with their students’ difficulties in geometry
was improved. 相似文献
979.
Issues associated with school absenteeism have attracted considerable attention and have long been one of the focal points of government strategies for school improvement. Pupil non-attendance is not a new phenomenon and featured prominently in Her Majesty’s Inspectors’ reports from 1839. This paper outlines the patterns of and influences on elementary education in early Victorian industrial Monmouthshire during the period 1839–1865. The twin problems of irregular attendance and early withdrawal of pupils are discussed together with the limitations and unreliability of contemporary statistics. An examination of the reasons for absence is then discussed together with the remedies proposed to alleviate the problem with particular reference to the contribution of the Prize Schemes. The paper illustrates the disadvantages of basing an educational system on voluntary endeavour and enlightened self-interest and highlights the paradox that, despite the introduction of mandatory attendance, the problem is still persistent and protracted and finding definitive solutions still remains elusive. 相似文献
980.
ZHANG Ji-gao 《浙江大学学报(A卷英文版)》2007,8(3):361-369
Particle pollution in air, also sometimes known as fine dust contamination, may cause electric contact failure. Recent research further proved that the fine particle is becoming a major disruption of the electronic connectors in signal transmission system. This paper specifies the connector contact in mobile phone application. To study the contact failure of mobile phone, a series of inspections and analytical research methods are introduced. Special features that cause the contact failure are summarized. Particle accumulation is the main problem; organic material such as lactates from sweat of the human body may act as adhesives to stick the separate particles together and make them adhere on the contact surface; chemical properties of dust cause serious local corrosion. The corrosion products may trap the particles and firmly attach on the contact surface; micro motion frequently occurs at the contact interface. Hard particle can be embedded into the surface, and soft particle could be squeezed and inserted into the contact; silicon compounds in dust play the most important role in forming high resistance regions that lead to failure; deposition of particles depends on the amount of materials, static electricity attracting force and gravity force applied on the particles. Current dust test can hardly reflect the serious contact failure. It is difficult to simulate the complexity of contact failure caused by particle contamination. Thus alternative ways of simulation experiment and improvement of contact reliability are proposed. 相似文献