997 resultados para Abelian groups.


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In Tanzania, indigenous forests can still be found whose existence is based on the management systems of precolonial society. This study covers material from over 900 forests. There are similar types of forests elsewhere in Africa, and similar forests can also be found in indigenous cultures on every continent. In this study they are called traditionally protected forests (TPFs). They have a high level of endemism and a rich biodiversity. The field study was carried out during the years 1997-2003 using participatory methods. An active debate is going on concerning the capacity of local communities to manage their environment. The role of indigenous people and their institutions in the development of the physical environment is a central issue in the debate. This study discusses the opportunities that the local people have had to decide on how to conserve, maintain, utilise, and manage their environment during different political periods. The study explains what kinds of changes have taken place in these forests and institutions in northeastern Tanzania among the matrilinear Zigua and patrilinear Gweno ethnic groups. About 2% of the land area of the communities was still protected by the precolonial structures. The communities have established their protection systems for different reasons, not only because of their beliefs but also because of different secular and clearly environmentally motivated reasons. There are different TPF types. Less than half of them are directly related to spirituality, and more than half are not. In earlier research elsewhere, it has been commonly understood that spiritual reasons played the main role in the protection of these environments. This study is also part of the postcolonial geographical discussion on the precolonial landscape and environmental management which was started by Carl Sauer. In the Zigua case study villages, only two out of five first comer clans have performed rain rituals in the past 30 years. Many of the most respected sacred sites do not have a ritual maker or even a person who knows how to perform rituals any longer. The same is happening with male initiation rites. In all case study villages there have been illegal cuts in the TPFs, but variations can be seen between the communities. The number of those who neither respect indigenous regulations nor accept indigenous penalties is growing. Positive developments have also taken place. Nowadays, the Forest Act of 2002 is in effect, which works as a cornerstone of community-based land ownership and also allows elders to protect TPFs, and by-laws are created with the support of different projects. Moreover, during the field study it was found that many young people are ignorant about their village's TPF sites, but interested in learning about their history and values.

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This paper reports on a study conducted in Indonesia at a time when two curricular reforms were underway. School-based curriculum was being implemented to allow Indonesian teachers more autonomy to develop curriculum to suit their local school community and its needs. Alongside this, the second concurrent reform introducing Character Education was more strongly prescriptive, requiring all teachers, including those working in language education, to address a particular set of stipulated values across all classes. The Indonesian schooling sector employs teachers at two different levels of professional status: civil servant teachers working in the higher status public sector and non-civil servant teachers who teach in the private Islamic Schools. Each level received different professional learning opportunities to prepare for the reforms. This study is interested in whether and how EFL teachers of different status exercised degrees of professionalism as they recontextualised these reforms in their classes. Nine teachers were interviewed and three of their classes were observed. This study found that the group of teachers with more professional learning could cope better with the weaker framing of school-based curriculum, while teachers with less professional learning reported disengagement with the reforms.

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The esterification of Ribonuclease-A in methanol/0.1 M hydrochloric acid has been studied by measuring the decrease in the number of titratable groups of the protein and estimating the amount of methanol incorporated. Esterification of nearly five of the 11 free carboxyl groups of the protein resulted in almost complete inactivation of the enzyme. The initial products of esterification have been chromatographed on Amberlite columns, and five partially active methyl ester derivatives of Ribonuclease-A have been isolated. The dimethyl ester, the initial product of esterification with reduced catalytic activity, has the carboxyl groups of Glu-49 and Asp-53 modified. Even in the non-aqueous solvent, as in the native structure of the protein in aqueous solution, these carboxyl groups are the fast reacting ones. Subsquently, the esterification reaction appears to proceed preferentially at the C-terminal region of the molecule. Comparison of the reactivities of carboxyl groups of Ribonuclease-A in acidic methanol to that known in aqueous solutions (with carbodiimides) suggests that the structure of Ribonuclease-A in the non-aqueous solvent resembles, at least in part, the structure in aqueous environment.

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In view of the recent interest in compounds containing M-SH units, an organotin hydrosulfide compound, Me2Sn(SH)(O2CMe) (1) was prepared by controlled hydrolysis of the diorganotin thioacetate. Under similar mild hydrolytic conditions the corresponding benzoate could not be isolated. Instead, the thiobenzoate complex, Me2Sn(SOCPh)(2) (3) was obtained in excellent yields indicating that there was no hydrolysis. Both 1 and 3 were characterized by X-ray crystallography. Some properties of the polymeric compound 1, such as spectral, electrical conductivity and NLO response were also studied. The reactivity and properties were explained using density functional calculations.

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Methods for the preparation of palladium(II) complexes of the type Pd(R-IAI)(IAI'), where IAI' is the anion of isonitrosoacetylacetoneimine and R-IAI, its N-alkyl or N-aryl derivative, are given.

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The effect of modification of carboxyl groups of Ribonuclease-Aa on the enzymatic activity and the antigenic structure of the protein has been studied. Modification of four of the eleven free carboxyl groups of the protein by esterification in anhydrous methanol/0.1 M hydrochloric acid resulted in nearly 80% loss in enzymatic activity but had very little influence on the antigenic structure of the protein. Further increases in the modification of the carboxyl groups caused a progressive loss in immunological activity, and the fully methylated RNase-A exhibited nearly 30% immunological activity. Concomitant with this change in the antigenic structure of the protein, the ability of the molecule to complement with RNase-S-protein increased, clearly indicating the unfolding of the peptide "tail" from the remainder of the molecule. The susceptibility to proteolysis, accessibility of methionine residues for orthobenzoquinone reaction and the loss in immunological activity of the more extensively esterified derivatives of RNase-A are suggestive of the more flexible conformation of these derivatives as compared with the compact native conformation. The fact that even the fully methylated RNase-A retains nearly 30% of its immunological activity suggested that the modified protein contained antibody recognizable residual native structure, which presumably accommodates some antigenic determinants.

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We develop a political-economic model of foreign aid allocation. Each ethnic group in the donor country lobbies the government to allocate more aid to its country of origin, and the government accepts political contributions from lobby groups. Initial per-capita income of the recipients and those of the ethnic groups are shown to be important determinants of the solution of the political equilibrium. We also examine the effects of changes in the degree of corruption, aid fatigue, and ethnic composition, in the donor country on the allocation of aid.

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This work demonstrates how the Australian core food groups system can be modified to enable the planning of vegan and lactovegetarian diets as well as omnivorous diets. In the modified version the cereals, vegetables and fruits groups remain the same as in the core food groups system, while the meat group is replaced with legumes, soya products, nuts and seeds. The milk group becomes milk or fortified soya milk, to allow for both lactovegetarian and vegan diets. The core food groups standard of 70% of the recommended dietary intake was adopted as a target for determining recommendations on the minimum number of serves from each food group. As found in the development of the core food groups system, zinc was the most limiting nutrient. Vitamin B 12 and calcium were other limiting nutrients in the vegan and lactovegetarian guides. The number of serves from each group required to meet 70% of the applicable recommended dietary intake has been calculated for children from four years old, adult men and women and pregnant and lactating women. It was found that the number of serves from each food group required in the vegan and lactovegetarian planning guides was in most cases similar to the number of serves of corresponding core food groups specified for a particular population group. This suggests that the vegan and lactovegetarian planning guides could be incorporated into a modified core food groups planning guide. Such a guide would cater for the general omnivorous population as well as for those seeking to avoid meat and/or dairy products. (Aust J Nutr Diet 1999:56:22-30) Key words: vegan, vegetarian, food guide, food groups, dietary planning.

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Peptide NH chemical shifts and their temperature dependences have been monitored as a function of concentration for the decapeptide, Boc-Aib-Pro-Val-Aib-Val-Ala-Aib-Ala-Aib-Aib-OMe in CDCl3 (0.001-0.06M) and (CD3)2SO (0.001-0.03M). The chemical shifts and temperature coefficients for all nine NH groups show no significant concentration dependence in (CD3)2SO. Seven NH groups yield low values of temperature coefficients over the entire range, while one yields an intermediate value. In CDCl3, the Aib(1) NH group shows a large concentration dependence of both chemical shift and temperature coefficient, in contrast to the other eight NH groups. The data suggest that in (CD3)2SO, the peptide adopts a 310 helical conformation and is monomeric over the entire concentration range. In CDCl3, the 310 helical peptide associates at a concentration of 0.01M, with the Aib(1) NH involved in an intermolecular hydrogen bond. Association does not disrupt the intramolecular hydrogen-bonding pattern in the decapeptide.

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We give it description, modulo torsion, of the cup product on the first cohomology group in terms of the descriptions of the second homology group due to Hopf and Miller.