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31.
Factors influencing conservation attitudes of local people in Western Serengeti,Tanzania 总被引:2,自引:0,他引:2
Jafari R. Kideghesho Eivin Røskaft Bjørn P. Kaltenborn 《Biodiversity and Conservation》2007,16(7):2213-2230
Attitudinal studies are increasingly being adopted as tools for evaluating public understanding, acceptance and the impact
of conservation interventions. The findings of these studies have been useful in guiding the policy interventions. Many factors
affect conservation attitudes positively or negatively. The factors inspiring positive attitudes are likely to enhance the
conservation objectives while those inducing negative attitudes may detrimentally undermine these objectives. The magnitude
of the resultant effects of each particular factor is determined by the historical, political, ecological, socio-cultural
and economic conditions and this may call for different management interventions. In this study we examined how conservation
attitudes in western Serengeti are shaped by the following factors: level of conflicts with protected areas; wildlife imposed
constraints (inadequate pasture, water, diseases, loss of livestock during migration, theft and depredation); participation
in the community based project; and socio-demographic factors (age, education level, wealth, immigration, gender and household
size). The results indicated that the level of conflicts, participation in the community based project, inadequate pasture,
lack of water, diseases, wealth and education were important in shaping peoples’ attitudes. However, in a stepwise linear
regression analysis, 59% of the variation in peoples’ attitudes was explained by three variables i.e., conflict level with
protected areas, lack of water and participation in the community based project. In addition to these variables, level of
education also contributed in explaining 51% of the variation in people’s attitude regarding the status of the game reserves.
Five variables (lack of water, level of education, inadequate pasture, participation in the community based project and diseases)
explained 12% of the variation in people’s attitude towards Serengeti National Park. The paper discusses the implications
for conservation of these results and recommends some measures to realise effective conservation of wildlife resources. 相似文献
32.
Soror SH Verma V Rao R Rasool S Koul S Qazi GN Cullum J 《Journal of industrial microbiology & biotechnology》2007,34(8):525-531
The genome sequence of Streptomyces coelicolor A3(2) contains 51 putative lipase and esterase genes mostly of unknown function. The gene estB (locus SCO 6966) was expressed as a His-tagged protein in E. coli. Esterase B was active at low temperatures exerting its maximum activity at 30°C and retaining more than 25% of its activity
at 4°C. The optimum pH was 8–8.5. The enzyme was active against short synthetic p-nitrophenylesters (C2–C10) with maximum activity towards the acetate ester (C2). The esterase was tested on 13 series of racemic esters of potential interest for the synthesis of chiral pharmaceutical
compounds. 4 of the series were substrates and a modest degree of enantioselectivity was observed (enantiomeric ratios of
1.1–1.9). 相似文献
33.
Žunić Vladimira Jafari Timea Hajnal Grabić Jasna Đurić Simonida Stamenov Dragana 《Journal of applied phycology》2022,34(2):903-913
Journal of Applied Phycology - Co-cultivation of plants and microalgae represents an optimized production method which is less resource intense and it is ecologically correct and clean.... 相似文献
34.
Comparative morphology,anatomy and palynological studies of perennial species of Onobrychis (Fabaceae) in northeast Iran
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This study examined morphological, anatomical and palynological characters for six species, two subspecies and two varieties of perennial Onobrychis growing in northeast Iran. In the morphological study, shape, size and color of vegetative organs and legumes were assessed. For the anatomical study, cross sections of mature fresh or dried stems, leaflets and petioles were prepared and stained. In the palynological study, pollen were extracted, acetolysed and observed by SEM. The morphological study indicated that some characteristics varied among species, such as shape of stipules and calyx teeth, color and shape of corolla segments and legumes and an identification key is provided based on these characters. Also, in internal structure some differences were noticed in the shape of petiole cross sections, the thickness of cortex and pith shape in petioles and the arrangement of vessels in stems. Some anatomical characters proved useful to identify species, but not sections. Palynological results showed circular and obtuse triangular pollen in polar view and elliptical pollen in equatorial view with reticulate ornamentation. In addition, a cluster analysis was done based on morphological, anatomical and palynological features. The resulting dendrogram confirmed the taxonomic treatment suggested by Sirjaev and Rechinger. 相似文献
35.
Mahmood Rasool Arif Malik Abdul Manan Khuram Aziz Amna Mahmood Saima Zaheer Naveed Shuja Mahmood Husain Qazi Mohammad Amjad Kamal Sajjad Karim 《Saudi Journal of Biological Sciences》2015,22(6):739-743
The present study was designed to explore the antioxidative status and circulating biochemical markers having a potential role in the pathogenesis of ethambutol (EMB) induced toxic optic neuropathy (TON) among diabetic and non-diabetic patients.Fifty patients under complete therapy of EMB for tuberculosis were included in the present study. Inclusion criteria for patients were to receive EMB everyday during treatment, a dose of 25 mg/kg for initial 2 months and 15 mg/kg during the rest of therapy period. We conducted color vision and visual acuity test for all patients.Fifteen out of fifty EMB induced TON patients, were found to be diabetic. Color vision and visual acuity test results were evaluated for diabetic and non-diabetic as well as twenty age matched controls. The results demonstrated a significant pattern of circulating biochemical markers between the studied groups. Data regarding hematological (RBC, p value = 0.02; Hemoglobin, p value = 0.02), hepatic (total bilirubin, p value = 0.01), renal (urea, p value = 0.03; creatinine, p value = 0.007), lipid (total cholesterol, p value = 0.01; total triglycerides, p value = 0.03) and antioxidative (superoxide dismutase, p value = 0.005; glutathione, p value = 0.02; catalase, p value = 0.02) profile showed a highly significant difference among the studied groups specially patients with diabetes. Malondialdehyde (MDA) level had gone significantly up in diabetic TON patients (p value = 0.02), in comparison to other antioxidants and vitamins (Vit). Vit-A, E, B1, B12 and Zinc seem to be playing a major role in the pathogenesis of TON, specially Vit-E and B1 surpassed all the antioxidants as having highly significant inverse relationships with MDA (MDA vs Vit-E, r = −0.676** and MDA vs Vit-B1, r = −0.724** respectively).We conclude that during the ethambutol therapy the decreased levels of Vit-E and Vit-B1 possibly play a role in the development of TON and may be used as therapeutic agents to lessen the deleterious effects of ethambutol. 相似文献
36.
Sadeghian H Seyedi SM Attaran N Jabbari A Jafari Z 《Journal of enzyme inhibition and medicinal chemistry》2011,26(2):238-244
A group of 2-alkoxy-5-methoxyallylbenzene were designed, synthesised and evaluated as potential inhibitors of the soybean 15-lipoxygenase (SLO) on the basis of the eugenol and esteragol structures. Compound 4d showed the best half maximal inhibitory concentration (IC??) for SLO inhibition (IC???=?5.9?±?0.6 μM). All the compounds were docked in the SLO active site retrieved from the Research Collaboratory for Structural Bioinformatics (RCSB) Protein Data Bank (PDB entry: 1IK3) and showed that the allyl group of the synthetic compounds similar to the linoleic acid double bond, were oriented toward the Fe3+-OH moiety in the active site of the enzyme and this conformation was especially fixed by the hydrophobic interaction of the 2-alkoxy group with Leu?1?, Trp?1?, Val??? and Ile??2. It was concluded that the molecular volume and shape of the alkoxy moiety was a major factor in the inhibitory potency variation of the synthetic compounds. 相似文献
37.
BACKGROUND: Pleomorphic adenoma of the breast is a rare benign tumor. Only a few cases have been reported. The histologic features have been described well. However, the cytologic findings have been described in only a few papers. CASE: A 47-year-old female presented with a left breast mass of several months' duration. The clinical and mammographic findings were highly suspicious for malignancy. Following an aspiration biopsy diagnosis of "positive for malignancy," the mass was excised. The histologic diagnosis was pleomorphic adenoma (mixed tumor of salivary gland type) rather than carcinoma. CONCLUSION: The cytologic presentation of pleomorphic adenoma of the breast can masquerade as that of a malignant tumor, in this case colloid carcinoma. This case delineates the cytomorphologicfeatures of pleomorphic adenoma, which may mimic carcinoma. 相似文献
38.
BACKGROUND: Breast cysts are mainly benign and are reported in association with fibrocystic disease and phyllodes tumor. Rarely have cystic changes been reported to occur in malignant tumors. They are usually small but large in rare cases. Giant breast cysts are very rare, and only a few cases have been reported. CASE: A 37-year-old woman presented with a rapidly growing breast mass. Mammography showed a huge, well-circumscribed cystic mass (17 x 16 x 16 cm) suggestive of a benign lesion. Cytologic examination revealed a highly cellular tumor composed of malignant cells of various sizes and shapes in a necrotic background. The smears were diagnosed as positive for malignancy and suggested metaplastic carcinoma. Mastectomy was performed, and histologic study confirmed the cytologic diagnosis. CONCLUSION: This is the first reported case of a breast cyst of this size. Clinically the cyst was confused with a benign lesion. The fine needle aspiration aided the diagnosis and planning of treatment. 相似文献
39.
40.
Somayeh Ghasemi Amir H. Khoshgoftarmanesh Hassan Hadadzadeh Mehran Jafari 《Journal of Plant Growth Regulation》2012,31(4):498-508
Supplying a sufficient amount of available iron (Fe) for plant growth in hydroponic nutrient solutions is a great challenge. The chelators commonly used to supply Fe in nutrient solutions have several disadvantages and may negatively affect plant growth. In this research study we have synthesized certain Fe-amino acid chelates, including Fe-arginine [Fe(Arg)2], Fe-glycine [Fe(Gly)2], and Fe-histidine [Fe(His)2], and evaluated their efficacy as an Fe source for two tomato cultivars (Lycopersicon esculentum Mill. cvs. ‘Rani’ and ‘Sarika’) grown in nutrient solution. Application of Fe-amino acid chelates significantly increased root and shoot dry matter yield of both tomato cultivars compared with Fe-EDTA. Tomato plants supplied with Fe-amino acid chelates also accumulated significantly higher levels of Fe, Zn, and N in their roots and shoots compared with those supplied with Fe-EDTA. In ‘Sarika’, the effect of Fe-amino acid chelates on shoot Fe content was in the order Fe(His)2?>?Fe(Gly)2?>?Fe(Arg)2. In ‘Rani’, the addition of all synthesized Fe-amino acid chelates significantly increased activity of ascorbate peroxidase (APX) in comparison with Fe-EDTA, whereas in ‘Sarika’, only Fe(His)2 increased shoot APX activity. The results obtained indicated that using Fe-amino acid chelates in the nutrient solution could supply a sufficient amount of Fe for plant uptake and also improve root and shoot growth of tomato plants, although this increase was cultivar-dependent. According to the results, Fe-amino acid chelates can be used as an alternative for Fe-EDTA to supply Fe in nutrient solutions. 相似文献