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991.
This paper explores the influence over time of past policies on people’s attitudes towards the use of forestland in Bangladesh. The discourses of the attitudes of people were captured from the observed social tradition towards forest resources. Forests were reserved systematically and solely through the Forest Department. The conservation processes were not participatory, and rights and tenure were strictly controlled. People were socially excluded and alienated from the forest, and the socio-political factors stimulated negative attitudes among people. Forests were considered to be government property, and therefore managing forests was the responsibility of the government. People only used forest resources to meet their own requirements, either with formal permission or illegally. This situation continued even after the independence of Bangladesh in 1971. As a result, the forests of Bangladesh have been degraded heavily in recent decades. 相似文献
992.
Our study focuses on predicting the ultimate short-term load carrying capacity of timber-to-timber connections with dowel-type fasteners. The wide range of possible configurations in practice makes the resolution of these values by tests unrealistic. Moreover, different current regulations do not consider some specific failure mechanisms. In many countries, the reduction of resistance involved by this phenomenon is taken into account by considering an effective number of dowels (nef) smaller than the actual number of dowels (n) in the connection. However, these different regulations disagree on the values of nef and on other points (spacing, partial coefficient of security, formulas). These discrepancies in design rules invite the fundamental research on this topic and, therefore, new methods are sought in order to estimate the load carrying capacities of the connections. In the light of these, our approach consists of predicting the load carrying capacity with the neural network numerical tool. The results obtained by this analysis tool are satisfactory, although the model remains complex. Subsequently, we focus on the simplification of this numerical model with classical regression techniques in order to implement it in a design code. 相似文献
993.
The aqueous extracts of Datura fastuosa leaves and seeds were evaluated for the analgesic effect on acetic acid-induced writhing and hot plate reaction in mice. According to the results, D. fastuosa leaves and seeds extracts at oral doses of 400 and 800 mg/kg are effective as analgesic. The analgesic activity of leaf extract is reduced by naloxone but not that of seed extract. 相似文献
994.
Carbonic anhydrase (CA, EC: 4.2.1.1) activity in teak (Tectona grandis L.f.) was studied to determine its characteristics, kinetics and isozyme patterns. We also investigated effects of leaf age, plant age and genotype on CA activity and gas exchange parameters. Carbonic anhydrase extracted from leaves in 12 mM veronal buffer, pH 7.8, had a K(m) for CO(2) of 15.20 mM and a V(max) of 35,448 U mg(-1) chlorophyll min(-1), which values declined by 50 and 70%, respectively, after 1 week of storage at 4 degrees C. A 15% native polyacrylamide gel revealed the absence of CA isozymes in teak, with only a single CA band of 45 kD molecular mass observed across 10 segregating half-sib families and groups of trees ranging in age from 10 to 25 years. Activity remained stable during the first month in storage at 0 degrees C, but gradually declined to 25% of the initial value after 1 year in storage. During the period of active growth (February-May), maximal CA activity was observed in fully expanded and illuminated leaves. Significant variation was observed in CA activity across 10 1-year-old half-sib families and 21 5-year-old half-sib families. There was a positive correlation between CA activity and photosynthetic rate in a population of 10-year-old trees (P < 0.005). Positive correlations between CA activity and photosynthetic rate were found in 10 of 21 5-year-old half-sib families (P < 0.005 to P < 0.05), which showed greater diversity in CA activity than in photosynthetic characteristics. Thus, CA may serve as a biochemical marker for photosynthetic capacity in teak genotypes. 相似文献
995.
Nicole MC Zeneli G Lavallée R Rioux D Bauce E Morency MJ Fenning TM Séguin A 《Tree physiology》2006,26(11):1377-1389
996.
The methanolic extract of the aerial parts of Satureja khuzistanica was investigated for its antimicrobial activity. The maximum antibacterial and antifungal activities were observed against Staphylococcus aureus and Candida albicans. 相似文献
997.
From the isopropyl acetate fraction obtained by partition of the leaves ethanolic extract of Alchornea glandulosa, six phenolic compounds were isolated and identified. General lethality of the extract, fractions and compounds were assayed with Brine Shrimp Test (BST) and with Antifeedant Activity Bioassay (AAB) against neonate larvae of Spodoptera frugiperda. Aqueous fraction and ethyl gallate, one of the major constituents of the polar fraction, have shown the highest toxicity in BST. Ethanolic extract, isopropyl acetate fraction and gallic acid reduced significantly larval growth of S. frugiperda neonates. 相似文献
998.
Atien Priyanti Rob Cramb Vyta W. Hanifah I. G. A. P. Mahendri 《Asia Pacific viewpoint》2015,56(3):335-350
Despite its small area and intensively cropped landscape, East Java accounts for 30% of Indonesia's cattle population. About two million households draw on family labour to raise cattle in backyard sheds and small enclosures, largely for cash income. In this paper, we examine the opportunity for such small‐scale producers to benefit from Indonesia's economic transformation, given the rising urban demand for beef. The paper reports on a study in two contrasting sites in East Java – irrigated lowlands and rainfed uplands – to explore the constraints facing small‐scale cattle producers in these environments, the means by which they have adapted to these constraints (especially by going beyond the farm household to access feed supplies) and possible means to enhance their production systems and incomes. The findings suggest that such cattle production systems can provide a viable source of livelihood, even for resource‐poor households; hence, appropriately adapted cattle improvement programmes are a sensible component of a pro‐poor development strategy. 相似文献
999.
Arnold S. Parco Mavir C. Avellaneda Anna H. Hale Jeffrey W. Hoy Collins A. Kimbeng Michael J. Pontif Kenneth A. Gravois Niranjan Baisakh 《Plant Breeding》2014,133(5):654-659
Brown rust, caused by the fungus Puccinia melanocephala, poses an increasing threat to sugarcane industries worldwide. Recently, markers R12H16 and 9020‐F4 were developed for a major resistance gene Bru1 that contributes to a significant proportion of brown rust resistance in multiple sugarcane industries. Marker‐assisted screening of Louisiana sugarcane germplasm showed a low frequency (4.3%, five out of 117 clones) of Bru1 among sugarcane cultivars and elite breeding clones. Likewise, among progeny of crosses involving wild/exotic germplasm, only 14 of 208 clones (6.7%) tested Bru1 positive. However, Bru1 frequency was higher (28.7%, 52 of 181 clones) in wild/exotic germplasm, which indicated that diverse genetic resources are available for Bru1 introgression. Commercial Bru1‐positive cultivar, ‘L 01‐299', was resistant to brown rust. However, Bru1‐positive cultivar, ‘L 10‐146’, was susceptible while Bru1‐negative cultivars, such as ‘L 99‐233’, showed resistance to brown rust. Bru1‐negative clones with brown rust resistance offer an opportunity to identify alternate sources of resistance, which can be pyramided with Bru1 for effective and durable resistance in sugarcane against the changing pathogen. 相似文献
1000.
M. E. Looseley R. Keith D. Guy G. Barral-Baron A. Thirugnanasambandam D. Harrap P. Werner A. C. Newton 《Euphytica》2015,203(2):337-347