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961.
962.
963.
Bryan J. Hains Gary L. Hansen Ronald J. Hustedde 《Cultural Studies of Science Education》2017,12(1):199-210
It can be argued that agricultural science is one of the original forms of science education. However, over the past century, agricultural science education has habitually been perceived as an educational venue meant solely for production agriculturalists. When examining modern agricultural education we find it to be a minority within the broader field of science education, contradicting its historically stout scientific standing within the sciences. This educational shift leaves one to ponder the historic development of contemporary agricultural education. To gain deeper insight into these questions we reviewed the historical evolution of agricultural education within the United States. We then examined the professional habitus, or cultural nuances, associated with contemporary agricultural education. Next, we considered potential outcomes associated with the profession embracing post-modern perspectives within mainstream science and community-based education. Finally, we call for critical venues within agriculture education to question the status quo and challenge the acceptance of commonly held views. 相似文献
964.
Karim-Aly S. Kassam Leanne M. Avery Morgan L. Ruelle 《Cultural Studies of Science Education》2017,12(1):97-118
Using two case studies of children’s knowledge, this paper sheds light on the value, diversity, and necessity of Indigenous and place-based knowledge to science and engineering curricula in rural areas. Rural contexts are rich environments for cultivating contextual knowledge, hence framing a critical pedagogy of teaching and learning. Indigenous and rural place-based knowledge are nuanced and pragmatic in character, and offer solutions to both local and global challenges. Two case studies, drawn from the experience of Lakota and Dakota communities and rural New York State, demonstrate the need to conserve, transmit, and contribute to Indigenous and rural knowledge through experiential and place-based education that bridges the gap between children’s knowledge and global STEM. This knowledge is inherently diverse in its complexity and connectivity to habitat, and when viewed in this light, has the capacity to transform our perspectives on educational practices and policies as well as our overall outlook on conserving both ecological as well as cultural diversity worldwide. Because diversity and knowledge are necessary for the survival of life on this planet, an enriched concept of pedagogical pluralism, in terms of multiple ways of knowing, is a necessity. 相似文献
965.
J. B. Varuna Kumara N. R. Ravikumara Basavaraj Madhusudhan 《Indian journal of clinical biochemistry : IJCB》2016,31(4):390-401
Folic acid is used for preventing and treating multiple diseases and disorders, administered in the form of oral supplements. The present research work was aimed to study the influence of two non-ionic surfactants Poloxamer and Tween 80 (Polysorbate 80) on pectin submicrospheres formulations. Typical natural polymer pectin was used to encapsulate folic acid by cross linking method. The resultant submicrospheres contributed to improve the aqueous solubility to enhance the bioavailability of folic acid. During investigation, it was observed that pectin polymers influenced kinetics of the rate of reaction more intensively than the surfactants. The physical phenomenon caused the change in their size, shape and chemistry of pectin polymers transforming into submicrospheres in aqueous condition. The characteristic differences of submicrospheres were assessed by scanning electron microscopy, differential scanning calorimetry and Fourier-transform infrared spectroscopy. The average diameters of the submicrospheres ranged between 250 and 500 nm. The encapsulation efficiency of submicrospheres ranged between 80 and 96 %. The characteristic swelling behavior of lyophilized submicrospheres was influenced by the ratio of pectin polymers and folic acid used in the formulations. The submicrospheres systems exhibited controlled release of folic acid due to the pH-dependent solubility of pectin polymers in aqueous medium. The submicrospheres showed good haemocompatibility suggesting them to be promising candidates for oral delivery. 相似文献
966.
967.
This paper explores links between the development of innovation theory since the late 1970s, and the evolution of innovation policy ideas, primarily in the 1990s. The argument is that there is a close connection between theory and policy, so that theory and policy learning can be seen as an integrated, co-evolving and interactive process. We analyse the theory-policy learning link in terms of two phases. We suggest that the complex economic crisis of the 1970s created an opening for rival analyses of events. During the 1980s, the development of evolutionary theories (pioneered by Nelson and Winter) and of empirically-based theories of the innovation process (pioneered by Nathan Rosenberg) created a framework in which policy agencies could consider heterodox ideas concerning objectives and instruments of public policy. By the early 1990s policy-makers, particularly in Europe, came to see RTD and innovation policies not just as important arenas of action in themselves, but as instruments towards more wide ranging policy objectives. The policy agencies involved, though hierarchical, were characterised by relatively open structures that permitted a degree of intellectual diversity: so organisations like the OECD and the European Commission played a central role, whereas the World Bank, for example, did not. Increasing policy interest stimulated a second phase of research in the 1990s, sponsored both nationally and by various EU programmes, in which expanding the innovation-oriented knowledge base became a significant objective for policy-makers. The paper argues that the theory-policy link has been central to the intellectual development of this field, which would have been impossible within the constraints of existing disciplinary structures and university funding systems. At the same time the analytical achievements have permitted a wide expansion in the conceptualization of policy targets and in the design of instruments available to policy-makers. In a sense, this is itself an evolutionary story: of a crisis and a conjunctural niche that permitted the creation and (so far) survival of a set of diverse and certainly non-conventional ideas. 相似文献
968.
S. K. Bansal H. N. Pandey A. Bansal L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1992,7(2):179-184
Circadian rhythm of serum glucose, pyruvate, lactate and lactate dehydrogenase (LDH) was studied in normal healthy young volunteers
at the onset (I Group, 7 cases) and peak (II Group, 8 cases) of winters in India with highly varied temperature. There was
a significant difference, in the circadian rhythm of glucose, pyruvate and lactate dehydrogenase (LDH) of the two groups.
A clockwise shift was observed in acrophase except in serum lactate, which is related to the energy demand in association
with time qualified changes in diurnal activity of the individuals and change in photoperiod. 相似文献
969.
Seema Gupta Rajesh Pandey Ranjan Katyal H. K. Aggarwal R. P. Aggarwal S. K. Aggarwal 《Indian journal of clinical biochemistry : IJCB》2005,20(1):67-71
The present study was conducted to evaluate some of the components of antioxidant defense system and oxidative damage in 20
male patients of alcoholic liver disease (ALD). The results were compared with 20 healthy male smokers and 20 healthy male
non-smokers volunteers. Patients were subjected to detailed clinical examination and laboratory investigations. Blood samples
were collected for estimating reduced glutathione (GSH), total thiols (T-SH) malondialdehyde (MDA), transaminases (AST, ALT),
glutathione-S-transferease (GST) and gammaglutamyl transferase (GGT). Serum aspartate amino transferase (AST)/alanine amino
transferase (ALT) ratio was significantly (p<0.01) reduced in ALD patients as compared to the controls. However, the core
of utility of MDA and GST was found to be significantly (p<0.01) increased in ALD patients compared to controls. There was
a significant negative correlation of MDA with both GSH and TSH. Plasma GGT levels were significantly (p<0.01) increased in
alcoholics and the enzyme showed a significant positive correlation with MDA. These results give enough evidence of increased
oxidative stress and compromised antioxidant defense system in patients with ALD. 相似文献
970.
R. K. Singh A. Bansal S. K. Bansal A. K. Upadhyay V. K. Singh 《Indian journal of clinical biochemistry : IJCB》1992,7(1):61-65
Nychthemeral rhythmicity of urinary copper (Cu) was studied in 40 clinically healthy volunteers and 35 renal stone formers.
A marked diurnal rhythm was noticed in urinary Cu levels in healthy subjects with maximum excretion at 0000 to 0600 hr followed
by a progressive fall during the rest of the period reaching minimum between 1200 to 1800 hr in males and 0600 to 1200 hr
in female volunteers. Similarly, all stone patients exhibited a definite rhythm in urinary Cu with significant amplitude and
acrophases at 2145 hr for males and 2141 hr for female stone formers. However, there was no difference in mean 24-hr Cu excretion
in male and female stone formers, whereas a significant change was observed in case of healthy subjects. Urinary Cu was found
to be significantly increased in renal stone formers in comparison to healthy controls of either sex attributing a significant
role of this overlooked trace mineral in the crystallization and/or activation of either of the process of stone formation
in the renal tubules. 相似文献