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41.
The importance of knowledge sharing, as an integral part of decision making, has been highly acknowledged by many authors. However, the process in which knowledge sharing should be conducted has remained a debatable issue. In this study, changes in experts’ attitudes, as a result of the knowledge-sharing process, in the context of rangeland management were assessed. We demonstrated a three-step knowledge-sharing process while recognizing collaborative knowledge sharing systems, which involves knowledge-sharing tools including face-to-face and virtual approaches. The process was applied to explore experts’ attitudes regarding livelihood alternatives in the Bazoft region of southwestern Iran. Sixty experts were selected from three groups categorized as key local stakeholders, practitioners, and scientists. First, the experts were independently given the task of ranking livelihood alternatives. Next, for a better understanding of alternatives and enhancing their view, additional knowledge and information were provided. Thereafter, their attitudes in the final step were assessed. According to the findings, change in the experts’ attitudes could take place, which eventually resulted in the prioritization of livelihood alternatives to approach sustainable rangeland management (SRM). The synergy of experts’ knowledge, which can be realized through a collaborative knowledge sharing process, can be further pursued by devising a workable policy framework to approach SRM.  相似文献   
42.
A 20-week growth trial was conducted to investigate the effect of two dietary blended vegetable oils (VO) on liver lipogenic enzyme activity, liver and gonad lipid class composition and fatty acid profiles, serum sex hormones, and gonad morphohistology in gilthead seabream, Sparus aurata. Three groups of fish (BW i 130.9 ± 3.1 g) were fed, close to satiation, three experimental diets: a control (CTRL) contained fish oil (FO) as the sole lipid source (100% FO) and two VO-blended diets in each 60% of FO was substituted by an equal mixture of cottonseed oil (CO), sunflower oil (SFO) and either linseed oil (LO) or soybean oil (SBO), designated as LO or SBO diet, respectively. Each diet was assigned to triplicate groups of fish. Results showed that all dietary treatments presented no significant (P > 0.05) differences in growth rate and feed conversion ratio for sexes combined. Enzyme activities of liver lipogenic enzymes of LO-fed fish (glucose-6-phosphate dehydrogenase (G6PDH), malic enzyme (ME) and fatty acid synthetase (FAS)) were not statistically (P > 0.05) different from those of CTRL fish. Only in the group of fish fed the SBO diet, G6PDH was slightly higher (P < 0.05) for both sexes, while ME showed a significant (P < 0.05) higher activity only in females relative to CTRL fish. Liver FAS enzyme activity remained unaltered among dietary groups. VO-fed fish recorded a significant (P < 0.05) increase in total lipid (TL) and triglyceride (TAG) contents in both liver and gonad, more pronounced in females than in males, concurrent with a significant (P < 0.05) decrease in cholesterol (CHL) and phospholipids (PL), more obvious for the SBO-fed fish, as compared to CTRL. The fatty acid (FA) composition of liver or gonad reflected that of the supplied diet and evidenced a significant (P < 0.01 or <0.05) alteration in the majority of individual FA in VO-fed fish compared to CTRL. There were decreased levels of ARA (20:4 n-6), EPA (20:5 n-3), and DHA (22:6 n-3) in VO-fed fish, more pronounced in females than in males, compared to CTRL. The liver and gonad FA profiles, for males and females, reflected the composition of the diet and showed sex variation in the output of multivariate principal component analysis (PCA). Feeding fish VO diets has also led to a significant (P < 0.05) reduction in serum estradiol level by 15.8 or 22.3% in LO- or SBO-fed fish, respectively, and in testosterone level by 7.7% in the latter dietary group only compared to the CTRL. Histomorphological examination of ovary and testis has indicated a relative retardation in oogenesis and spermatogenesis in VO-fed fish, less obvious in the LO-fed fish compared to CTRL. These results suggest a preference of LO over SBO blend diet in terms of liver lipogenic enzyme activity, liver and gonad lipid content, lipid class composition and fatty acid profile, serum sex hormones as well as gonad maturation. PCA analysis of gonads highlighted the importance of using a 100% marine FO diet for gilthead seabream broodstock for the recovery of a normal FA profile in gonads of fish, previously fed VO over the production cycle, to ensure successful spawning.  相似文献   
43.
Background: The aim of this research was to study the distribution and changes of glycoconjugates particularly their terminal sugars by using lectin histochemistry during mouse spinal cord development. Methods: Formalin-fixed sections of mouse embryo (10-16 fetal days) were processed for lectin histochemical method. In this study, two groups of horseradish peroxidase-labeled specific lectins were used: N-acetylgalactosamine, including Dolichos biflorus, Wisteria floribunda agglutinin (WFA), Vicia villosa, Glycine max as well as focuse-binding lectins, including tetragonolobus, Ulex europaeus, and Orange peel fungus (OFA). All sections were counterstained with alcian blue (pH 2.5). Results: Our results showed that only WFA and OFA reacted strongly with the floor plate cells from early to late embryonic period of developing spinal cord. The strongest reactions were related to the 14, 15, and 16 days of tissue sections incubated with OFA and WFA lectins. Conclusion: The present study demonstrated that cellular and molecular differentiation of the spinal cord organizers is a wholly regulated process, and α-L-fucose, α-D-GalNAc, and α/β-D-GalNAc terminal sugars play a significant role during the prenatal spinal cord development.Key Words: Development, Glycoconjugates, Spinal cord  相似文献   
44.
Stemphylium lycopersici (Enjoji) W. Yamam was initially described from tomato and has been reported to infect different hosts worldwide. Sequence analyses of the internal transcribed spacer (ITS) regions 1 and 2, including 5.8S rDNA (ITS-5.8S rDNA) and glyceraldehyde-3-phosphate dehydrogenase (gpd) gene, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR), as well as virulence studies were conducted to analyze 46?S. lycopersici isolates. Stemphylium lycopersici isolates used in this study were obtained from diseased tomato (Solanum lycopersicum L.), eggplant (Solanum melongena L.), pepper (Capsicum annuum L.) and lettuce (Lactuca sativa L.) from major vegetable growing regions of Malaysia, including the three states of Pahang, Johor and Selangor between 2011 and 2012. Phylogenetic analysis of a combined dataset of the ITS-5.8S rDNA and gpd regions indicated that all isolates were clustered in the sub-cluster that comprised S. lycopersici, and were distinguished from other Stemphylium species. Cluster analyses using the UPGMA method for both RAPD and ISSR markers grouped S. lycopersici isolates into three main clusters with similarity index values of 67 and 68 %. The genetic diversity data confirmed that isolates of S. lycopersici are in concordance to host plants, and not geographical origin of the isolates. All S. lycopersici isolates were pathogenic on their original host plants and showed leaf spot symptoms; however, virulence variability was observed among the isolates. In cross-inoculation assays, the representative isolates were able to cause leaf spot symptoms on eggplant, pepper, lettuce and tomato, but not on cabbage.  相似文献   
45.
Native grasses are excellent candidate species for manipulation to produce dwarf and turf type varieties as well as for producing cultivars with higher attractiveness and requiring less maintenance to be used as a turf grass in arid and semi-arid regions of the world. This investigation was conducted to explore visual qualities of native grasses and their mixtures compared to commercial turf. The field experiment was set out in a split-plot in time based on a randomized experimental design with three replications. We used two native monoculture accessions, perennial ryegrass (Lolium perenne L. ‘Yarand’) and (Lolium perenne L. ‘Shadegan’), Native low-variety Mixture (NM1): consisting of 50% Lolium multiflorum ‘Shadegan’? 50% Festuca spp. ‘Shadegan’, Native high-variety Mixture (NM2): consisting of 55% Lolium perenne L. ‘Yarand’? 35% Lolium perenne L. ‘Shadegan’? 5% L. multiflorum ‘Shadegan’ and 5% Festuca spp. ‘Shadegan’ and compared this with one commercial turf mixture that is commonly used in landscaping. Results indicated the effects of seasons and turf grass types and their interaction had significant effects on most variables including quality, season color, leaf texture, density, quality after clipping (p < 0.01). The visual quality measurements indicated the superiority of L. perenne ‘Shadegan’ over other native monoculture and polyculture and its ablility to compete with the commercial turf. The native turf mixture of NM2 showed several good characteristics. L. perenne ‘Yarand’ had statistically the lowest score for visual appeal as compared with the other turf types. This research suggests that the use of native grass species of L. perenne ‘Shadegan’ is worth investigating for better performance of the native landscape.  相似文献   
46.
Using plant extracts as immunostimulants in aquaculture has prove effectiv in resisting infectious disease, in addition to being safe and inexpensive. The present study is concerned about the prospective mode of action of using lesser galangal extract (Alpinia officinarum) encapsulated into amine surface functionalized mesoporous silica nanoparticles (MSN) in order to elevate the immune status of rainbow trout (Oncorhynchus mykiss). Fish were randomly divided into 6 groups and fed for 4 weeks with commercial diets supplemented with 0% (control), 0.5% and 1.5% of lesser galangal extract, and with previous concentrations encapsulated with MSN (0.5% + MSN, 1.5% + MSN) and MSN (without extract). The effects of the feeding trial on the innate humoural immune parameters (total protein, myeloperoxidase content, lysozyme antiproteases and bactericidal activities) in rainbow trout were examined. Also, the influence of dietary supplement on some immune‐related genes in rainbow trout head kidney (TNF, IL‐8, IL‐1b, LYZ2 and CD4) after challenge with Yersinia ruckeri was examined. The results revealed enhancement in immune parameters in all treatment groups compared to the control, especially in the fish group fed with 1.5% + MSN which showed the highest significant difference (p < .05) in total protein, lysozyme and antiproteases activities. Also, feeding lesser galangal extract encapsulated into MSN led to an increase in myeloperoxidase content and bactericidal activity. An improvement in the expression of immune‐related genes has been recorded in fish groups fed doses of lesser galangal extract and lesser galangal extract encapsulated into MSN compared to the control or to the group fed with MSN only. Particularly, the group fed with 0.5% + MSN showed a significant up‐regulation in most of the immune‐related genes. The current investigation supports using lesser galangal extract encapsulated into MSN in fish diets as a supplement to enhance the immune response of rainbow trout and elevate its resistance to infectious diseases.  相似文献   
47.
The objective of this study was to determine the effects of genistein or 17β‐estradiol (E2) on the reproductive physiology in male gibel carp, Carassius auratus gibelio. Maturing male gibel carp received intraperitoneal injections of E2 (10 µg/g body weight), one of two genistein doses (5 µg/g body weight, G5, or 50 µg/g body weight, G50), or the injection vehicle every other day for 10 d. Disruptions in reproductive capacity were determined by measuring indices of sperm quality, plasma metabolites and sex steroids, histological analyses of testes, fertilization rate, and offspring viability. E2 and genistein treatment reduced gonadosomatic index and milt volume, while reduction in spermatozoa concentration and spermatocrit occurred only in E2 and G50‐treated males. Histological examination of the testes indicates that E2 and genistein inhibited reproductive capacity through disruption of the spermatogenesis in males. Genistein reduced fertilization rate and offspring viability at 6 d after hatch (d.a.h.). Plasma testosterone and E2 decreased and increased, respectively, with E2 and G50 treatment. E2 and G50 treatment altered plasma metabolite phosphorus, calcium, cholesterol, and triglyceride. These findings indicate that genistein can negatively affect reproductive capacity in male gibel carp, suggesting that high dietary genistein may impair gonad development.  相似文献   
48.

Background:

Hyperprolactinemia is a common side effect of antipsychotic drugs that requires further investigation. The current study was designed to evaluate dose-dependent effect of chlorpromazine (CPZ) on hormonal changes and uterine horn histological structure in rats. Moreover, the mammary glands were analyzed to show hyperprolactinemia-induced histological changes.

Methods:

Albino Wistar rats (n = 32) were divided into four groups. The first group was set as a control. In the three drug-treated groups (eight rats in each group), CPZ was administered by a gavage at doses of 3, 10, and 30 mg/kg/day for 28 days. One day after the last administration of the drug, the animals were sacrificed. Histopathological and histomorphometrical analyses of the uterine horns and mammary glands were carried out to evaluate dose-dependent effect of CPZ on histological structure. Serum levels of prolactin (PRL), estradiol, progesterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were also evaluated.

Results:

Remarkable (P < 0.05) elevation was observed in CPZ-administrated animals'' uterine horn endometrium, myometrium, and perimetrium thicknesses, and the mammary glands were observed with galactorrhea features. The serum level of progesterone and PRL significantly (P < 0.05) increased, while the serum concentration of LH, FSH, and estradiol was notably (P < 0.05) decreased depending on administrated CPZ dose. No histological and biological changes were occurred in the control animals.

Conclusion:

The present findings suggest that CPZ-induced disturbances not only depend on PRL level and increased PRL level largely depends on administrated doses of the CPZ. Key Words: Hyperprolactinemia, Uterus, Rats  相似文献   
49.
In this work, the natural dyeing behavior of woollen yarn with madder (Rubia tinctorum L.) root extract was studied. The effects of different tannin-rich plants (Rhus coriaria, Eucalyptus, Terminalia chebula, Quercus castaneifolia, Pomegranate) extract as biomordants and alum (as a chemical mordant) with two mordanting procedures (pre- and metamordanting) on color characteristics of the dyed samples were also investigated. The CIEDE2000 values, color strength (K/S), washing fastness and tensile property of the mordanted and dyed samples were assessed. Visually, a range of hues from orange to brownish-red were obtained. In general, pre-biomordanted samples with Rhus coriaria (10 %owf), Eucalyptus (10 %owf), Terminalia chebula (5 %owf), Quercus castaneifolia (5 %owf) and Pomegranate (5 %owf) showed almost the same color difference (ΔE00) and wash fastness values compared to those treated with 3 %owf alum. Finally, it was concluded from the comparative studies that the biomordants have good potential to be considered as alternatives to the common chemical mordants.  相似文献   
50.
Thymus pubescens is an aromatic and medicinal plant, which has been widely distributed in Iran. The anti-inflammatory and analgesic effects of the T. pubescens aerial parts methanol extract were studied at doses of 50-400 mg/kg i.p. using carrageenan-induced edema, formalin, hot plate and writhing tests. The extract produced a significant decrease in the degree of swelling, 3 h after carrageenan injection and caused graded inhibition of both phases of formalin-induced pain. Moreover, in the hot plate test, it significantly raised the pain threshold. While in the writhing test produced a significant decrease in the number of writhing in comparison with the control group (P<0.001). The results of pharmacological tests performed in the present study suggest that the extract of T. pubescens presents analgesic and anti-inflammatory effects.  相似文献   
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