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Fatemeh Bakhtiari Jette Bredahl Jacobsen Frank Søndergaard Jensen 《Urban Forestry & Urban Greening》2014,13(4):662-671
Conflicts among forest visitors have direct effects on the quality of a recreational experience. As the number of visitors to forests close to residential areas increases, as well as the number of different activities, so does the potential for perceived conflicts. According to the literature, expanding knowledge of conflict characteristics and their causes is important for recreation planners and managers who aim to reduce conflicts.In the present study, different forest user groups were identified and categorised according to their pursued activities, and for each group, causes of conflict were identified. Furthermore, a choice experiment was constructed to estimate the distance visitors are willing to travel to encounter few visitors as opposed to many visitors, and thereby potentially experience fewer conflicts. Comparing the marginal willingness to travel (WTT) of different user groups suggests that some groups have a WTT further than the average to reach a forest with ‘Few’ visitors. The average WTT to reach a forest area with ‘Few’ visitors. ‘Mountain bikers,’ ‘Peace and nature lovers’ and ‘Horse riders’ are willing to travel 4 km more than the average per visit to reach a less crowded forest. At the other end of the scale, we find that people who are doing physical exercise are willing to travel 2 km less than the average to reach a less crowded forest. 相似文献
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An experiment was carried out to assess the influence of tannic acid (TA) on integrity of the intestine in broiler chicks vaccinated against coccidiosis and challenged with the disease. In a 2 × 2 factorial design, the trial had five groups of 10 chickens each, including positive (group 2) and negative (group 1) controls. The chickens were kept on wood shavings and fed a commercial maize and soybean-based starter-grower diet. From day 1, groups 3 and 5 received TA (10 g kg(-1)) in their diet. On day 4, birds of groups 4 and 5 were vaccinated orally against coccidiosis with anti-coccidial vaccine, Livacox T?. Each dose of the vaccine contained 300-500 sporulated oocysts of each of Eimeria acervulina, Eimeria maxima and Eimeria tenella. On day 18, all experimental groups except for the negative (group 1) were challenged with 10-fold dose of Livacox T? to produce a mild coccidiosis infection. Faecal samples of individual birds were collected on day 23, and the number of faecal oocysts was determined. d-Xylose absorption test was also carried out on all birds on day 23. Immediately after d-xylose absorption test, all birds were killed humanely and the intestinal tract was removed, weighed and examined for gross lesions. Results showed that negative (group 1) and positive controls (group 2) had the highest and lowest levels of plasma d-xylose post-ingestion of the substrate, respectively. Vaccination and/or feeding TA raised the level of plasma d-xylose in infected birds, although this was not significant for TA-fed birds. Vaccination reduced but TA increased the total number of oocysts per gram of faeces. Birds of groups 2-5 had distinct intestinal lesions when compared with group 1. However, vaccination prevented intestinal lesions. Relative weights of intestinal parts were the lowest in group 1 and the highest in group 2. Vaccination but not TA reduced the relative weights of intestinal parts in infected birds. It was concluded that dietary tannins may reduce the efficacy of anticoccidial vaccines and alter the proper development of immunity against the disease. 相似文献
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Hesam A. Seifi DVM DVSc Hooshang Gray DVM Mehrdad Mohri DVM DVSc Arya Badiee DVM DVSc 《Journal of Equine Veterinary Science》2002,22(5)
The susceptibility of Caspian miniature horses to hyperlipidemia was followed in a study of healthy Caspian miniature horses in which food but not water was withheld for 48 hours. Two months before the study, the horses were fed a high-energy diet. The mean of weight gain was 26.46 kg per horse during this period. All horses had a normal rectal temperature, respiratory rate, and pulse throughout the experiment. During the period of food deprivation, levels of serum triglyceride, aspartate aminotransferase, and alanine aminotransferase significantly (P < .05) increased and glucose concentration decreased. As a conclusion, Caspian miniature horses were susceptible to hyperlipidemia, but they did not show classic hyperlipemia syndrome. 相似文献
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Farzam Tavankar Angela Lo Monaco Mehrdad Nikooy Rachele Venanzi Amireslam Bonyad Rodolfo Picchio 《林业研究》2019,(4):1383-1394
Snow damage on natural stands is an important problem concerning mountainous forest management.In the present research,the frequency and intensity of heavy snow damage on natural stands and the relationship of damages with characteristics of trees,stand and topography were studied in mountainous forests of northern Iran.A systematic sampling design was applied to the study area(140 ha),with 122 circular plots.The grid dimension was100 m and each plot area was 1000 m^2.The four types of snow damage to trees include:crown damage(8.6%),stem breakage(5.4%),uprooting(3.2%),and bending(1.4%).The frequency of crown damage grew with an increase inthe diameter at breast height(DBH),while the frequency of stem breakage,uprooting and bending decreased with an increase the DBH.The frequency of crown damage,stem breakage,and total damages was related to tree species(p<0.01).Not all tree species were equally susceptible to snow damage.The amount of damage grew with increasing elevation and slope angle and decreased with increasing soil depth.Young trees(DBH<25 cm)were more susceptible to snow damage than other trees.Snow damage decreased by as the trees in the stand became more mixed in age.The susceptibility of trees to snow damage increased by height and slenderness coefficient.With adequate silvicultural operation,snow damage can be reduced to a minimum level in these natural forests. 相似文献
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Majid Salehi Ahmad Vaez Mahdi Naseri-Nosar Saeed Farzamfar Arman Ai Jafar Ai Shima Tavakol Mehrdad Khakbiz Somayeh Ebrahimi-Barough 《Fibers and Polymers》2018,19(1):125-134
In the present study, naringin, a flavonoid isolated from the grape and citrus fruit species, was incorporated with poly(ε-caprolactone)/gelatin composite mats in order to develop a potential wound dressing. The composite mats were prepared by electrospinning of poly(ε-caprolactone)/gelatin (1:1 (w/w)) solution incorporated with 1.50 %, 3 % and 6 % (w/w) of naringin. The electrospun mats were evaluated regarding their morphology, contact angle, water-uptake capacity, water vapor transmission rate, tensile properties, drug release, cellular response and in vivo wound healing activity. The study showed that after 2 weeks, the full-thickness excisional wounds of Wistar rats treated with the naringin-loaded dressings achieved a wound closure of higher than 94 % and the dressing containing 6 % (w/w) naringin had almost 100 % wound closure. The sterile gauze, as the control group, showed nearly 86 % of wound closure after this period of time. Our results provided evidence that supports the possible applicability of naringin-loaded wound dressing for successful wound treatment. 相似文献
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Serum lipid and lipoprotein parameters of Turkman horses 总被引：1，自引：0，他引：1
Asadi F Mohri M Adibmoradi M Pourkabir M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(3):332-334
BACKGROUND: Lipid transport systems in animals have been evaluated both as experimental models for lipid and lipoprotein metabolism in humans and to gain insight into the lipid metabolism of specific breeds. The Turkman horse is a pure-blooded horse that lives on the margins of the Caspian Basin; information about serum lipids and lipoproteins in this breed is lacking. OBJECTIVE: The purpose of this study was to evaluate serum lipid and lipoprotein concentrations in clinically healthy Turkman horses. METHODS: Concentrations of triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDLC), low density lipoprotein cholesterol (LDL-C), and very low density lipoprotein cholesterol (VLDL-C), and lipoprotein electrophoretic patterns were determined in serum samples from 48 Turkman horses of both sexes and 0-12 years of age. Results were analyzed by 1-way ANOVA. RESULTS: In both sexes and all age groups, the relative percentages of LDL-C (44.2-64.3%) were higher than those of HDL-C (29.7-47.1%) and VLDL-C (5.9-9.0%). Serum concentrations of TG and TC were significantly higher in male (0.45 +/- 0.12 mmol/L; 2.70 +/- 0.45 mmol/L) than in female (0.34 +/- 0.1 mmol/L; 2.15 +/- 0.3 mmol/L) horses in most age groups. The relative percentages of alpha- and beta-lipoproteins in electrophoretic tracings were 62.77 +/- 5.05% and 36.67 +/- 4.29%, respectively. CONCLUSION: Serum lipid and lipoprotein values in Turkman horses differ from those of other equine breeds, and may be useful for evaluating metabolic diseases in this species. 相似文献
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Hamid Reza Ahmadnia Motlagh Mehrdad Farhangi Gholamreza Rafiee Farzaneh Noori 《Aquaculture International》2012,20(4):693-705
The aim of this study was to evaluate the effects of Bacillus subtilis and Bacillus licheniformis on growth, gut microbiota, and digestive enzyme activities of Artemia urmiana. Three diets containing 102 (T1), 104 (T2), 106 (T3) CFU of probiotics/g feed, and a control diet (C) without probiotic were used through a completely randomized design (treatments with triplicates). Twelve plastic tanks with the capacity of 60- l and density of 20 nauplii/ml were used and the trial continued for 15?days. Results showed that probiotics significantly increased the total length of A. urmiana (P?<?0.05). Although the total aerobic gastrointestinal bacteria count showed no significant differences among the treatments, the total Bacillus count significantly increased in experiments (P?<?0.05). The ratio of TCBS to total aerobic bacteria count was significantly lower in T1 (0.31?±?0.05), T2 (0.27?±?0.15), and T3 (0.25?±?0.05) compared to the control (0.76?±?0.34) (P?<?0.05). The probiotics were able to increase the protease and amylase activities (P?<?0.05). No significant effect on lipase activity. The study determined T2 and T3 as the most effective treatments for improving growth, bacterial flora, and digestive enzyme activities. As less probiotic needed in T2, using 104 bacteria per g diet is recommended for rearing Artemia up to the maturity stage. 相似文献