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排序方式: 共有256条查询结果,搜索用时 340 毫秒
41.
Fatemeh RAJAEI Abbas E SARI Abdolrassoul SALMANMAHINY Timothy O RANDHIR Majid DELAVAR Reza D BEHROOZ Alireza M BAVANI 《干旱区科学》2018,10(3):457-469
Conversion of forest land to farmland in the Hyrcanian forest of northern Iran increases the nutrient input, especially the phosphorus(P) nutrient, thus impacting the water quality. Modeling the effect of forest loss on surface water quality provides valuable information for forest management. This study predicts the future impacts of forest loss between 2010 and 2040 on P loading in the Tajan River watershed at the sub-watershed level. To understand drivers of the land cover, we used Land Change Modeler(LCM) combining with the Soil Water Assessment Tool(SWAT) model to simulate the impacts of land use change on P loading. We characterized priority management areas for locating comprehensive and cost-effective management practices at the sub-watershed level. Results show that agricultural expansion has led to an intense deforestation. During the future period 2010–2040, forest area is expected to decrease by 34,739 hm~2. And the areas of pasture and agriculture are expected to increase by 7668 and 27,071 hm~2, respectively. In most sub-watersheds, P pollution will be intensified with the increase in deforestation by the year 2040. And the P concentration is expected to increase from 0.08 to 2.30 mg/L in all of sub-watersheds by the year 2040. It should be noted that the phosphorous concentration exceeds the American Public Health Association′s water quality standard of 0.2 mg/L for P in drinking water in both current and future scenarios in the Tajan River watershed. Only 30% of sub-watersheds will comply with the water quality standards by the year 2040. The finding of the present study highlights the importance of conserving forest area to maintain a stable water quality. 相似文献
42.
The effects of replacing fish meal (FM) with corn gluten meal (CGM) on growth and physiological performance were evaluated in common carp (Cyprinus carpio). Six experimental diets were formulated by substituting 0 (control), 20, 40, 60, 80, and 100% CGM protein for FM protein. The concentrations of dietary protein in the experimental diets were 27.8–29% and the P:E ratios were 14.7–15.46 mg/kJ. Eighteen fish with an initial weight of 13.5?±?0.1 g were allocated to each of 18 circular tanks (450 L) to give triplicate groups for each dietary treatment. The fish were fed to satiation for 8 weeks. At the end of the feeding trial, growth indices, body proximate composition, and hematological and biochemical parameters were measured. Blood samples were taken from six fish in each tank. Final weight and total length were significantly higher in fish fed 100% CGM (27.8?±?1.2 g and 11.9?±?0.3 cm) than for those fed the control (22.7?±?1.4 g and 10.9?±?0.5 cm) or 20% CGM (22.3?±?1.2 g and 11?±?0.4 cm) diets. No effect of FM replacement by CGM was observed for condition factor or hepatosomatic index (P?>?0.05). The highest value of protein productive value (14.31?±?0.65) was observed in fish fed 20% CGM (P?<?0.05). There were no significant differences in percentage body moisture and fat, but percentages of protein and ash were significantly different among experimental groups; the highest values of protein (15.6?±?0.24%) and ash (3.01?±?0.26%) were recorded in fish fed 40% CGM. For hematological parameters, the highest number of white blood cells (4.1?±?0.1?×?103 mm?3) was observed in fish fed 100% CGM (P?<?0.05). In addition, the highest hematocrit (42.1?±?0.7%) and triglyceride (294.11?±?23.82 mg dl?1) were seen in fish fed the diet containing 40% CGM, while 80% CGM gave the highest cholesterol level (204.44?±?9.0 mg dl?1; P?<?0.05). Replacement of FM with CGM had no negative effects on growth and physiological parameters of common carp fingerlings in this short (8 weeks) trial, suggesting that it may be feasible to replace FM with CGM in diets formulated for juvenile common carp. 相似文献
43.
Amir Abbas Bazyar Lakeh Hamid Farahmand Werner Kloas Alireza Mirvaghefi Achim Trubiroha Brian C. Peterson Sven Wuertz 《Aquaculture International》2016,24(1):11-21
Juvenile rainbow trout (Oncorhynchus mykiss) were passively immunized by intraperitoneal immunization against somatostatin-14 (SS-14) using an antibody originating from egg-laying chicken (Gallus domesticus). Fish were immunized weekly (0, 7, 14, 21, 28, 35 days) with chicken egg yolk-derived immunoglobulin (IgY) against SS-14 (1:25 IgY, 5 mg mL?1), and growth performance, feed utilization as well as plasma concentrations and mRNA levels of growth hormone (GH) and insulin-like growth factor I (IGF-I) were compared to the control group that received placebo immunization with PBS. Passive immunization significantly increased weight gain of treated fish (67.7 ± 7.4 g) compared to the control group (40.1 ± 2.0 g) after 35 days (p < 0.05). Feed conversion ratio (FCR) was significantly improved in the immunized fish (0.7 ± 0.08) compared to control group (1.2 ± 0.06) (p < 0.05). The concentrations of GH and IGF-I in the blood plasma showed no significant differences between the fish treated with anti-SS-14 and those of control during the treatment (p > 0.05). In both groups, GH levels decreased over the 35 days of the experiment (p < 0.05). However, IGF-I level during the period of treatment remained unchanged in both control and immunized fish with the anti-SS-14. Similarly, no changes were observed in pituitary GH and liver IGF-I mRNA levels between treatment and control at each sampling time (p > 0.05). There was no indication of a cumulative, long-lasting effect of repeated immunization on GH or IGF-I plasma concentrations or mRNA expression. The present study shows that a passive immunization of rainbow trout against SS-14 using a chicken egg yolk-derived SS-14 antibody could increase growth rate and improved FCR. 相似文献
44.
Journal of Plant Diseases and Protection - Bacterial blight of common bean caused by Xanthomonas axonopodis pv. phaseoli (Xap) is one of the most devastating diseases and causes serious yield... 相似文献
45.
Neil R Smalheiser Vetle I Torvik Amanda Bischoff-Grethe Lauren B Burhans Michael Gabriel Ramin Homayouni Alireza Kashef Maryann E Martone Guy A Perkins Diana L Price Andrew C Talk Ruth West 《Journal of Biomedical Discovery and Collaboration》2006,1(1):8
Arrowsmith is a unique computer-assisted strategy designed to assist investigators in detecting biologically-relevant connections between two disparate sets of articles in Medline. This paper describes how an inter-institutional consortium of neuroscientists used the UIC Arrowsmith web interface http://arrowsmith.psych.uic.edu in their daily work and guided the development, refinement and expansion of the system into a suite of tools intended for use by the wider scientific community. 相似文献
46.
Background: The primary phase of traumatic spinal cord injury (SCI) starts by a complex local inflammatory reaction such as secretion of pro-inflammatory cytokines from microglia and injured cells that substantially contribute to exacerbating pathogenic events in secondary phase. Valproic acid (VPA) is a histone deacetylase inhibitor. Acetylation of histones is critical to cellular inflammatory and repair processes. Methods: In this study, rats were randomly assigned to five experimental groups (laminectomy, untreated, and three VPA-treated groups). For SCI, severe contusion was used. In treated groups, VPA was administered intraperitoneally at doses of 100, 200 and 400 mg/kg daily three hours after injury for 7 days. To compare locomotor improvement among experimental groups, behavioral assessments were performed by the Basso, Beattie and Bresnahan (BBB) rating scale. The expression of neurotrophins was evaluated by RT-PCR and real-time PCR. Results: VPA administration increased regional brain-derived neurotrophic factor and glial cell-derived neurotrophic factor mRNA levels. Local inflammation and the expression of the lysosomal marker ED1 by activated macrophages/microglial cells were reduced by VPA and immunoreactivity of acetylated histone and microtubule-associated protein were increased. Conclusion: The results showed a reduction in the development of secondary damage in rat spinal cord trauma with an improvement in the open field test (BBB scale) with rapid recovery.Key Words: Inflammation, Epigenetics, Valproic acid (VPA) 相似文献
47.
Zabihallah Bahmani Masoud Rezaei Seyed Vali Hosseini Seyed Fakhreddin Hosseini Alireza Alishahi Mehraj Ahmad 《Journal Of Aquatic Food Product Technology》2013,22(6):542-551
Research has shown that fresh fish is an extremely perishable food as compared to other food commodities. In this study, quality deterioration during storage of golden grey mullet (GGM) iced for 0, 6, and 12 h after landing was monitored. Microbiological indices (total viable count, TVC; psychrophilic counts, PTC; lactic acid bacteria, LAB; and Enterobacteriaceae counts, EBC), chemical parameters (pH; total volatile basic nitrogen, TVB-N; peroxide value, PV; thiobarbituric acid, TBA; and free fatty acids, FFA) values increased over the preicing duration. Delayed icing did not lead to significant increases (p > 0.05) in TVC, PTC, LAB, and EBC throughout the period of storage. All chemical indices increased during storage (p < 0.05). This study showed that sensorial analysis of GGM correlated well with microbiological analysis. Results of this study based on the microbiological and raw fish sensorial data indicated that the shelf life of GGM stored in ice immediately after catch was approximately 10–11 days, while the 6- and 12-h delays in icing shortened the shelf life to approximately 6–7 and 2–3 days, respectively. 相似文献
48.
Fatemeh Ranjbar Parviz Rezvani Moghaddam Alireza Koocheki 《Communications in Soil Science and Plant Analysis》2017,48(7):801-807
Essential oil content and concentration of anise plant planted in different times under various sources of nitrogen was evaluated in this study. The experiment was conducted in a split plot based on a randomized complete block (RCB) design (different sources of fertilizer as the main plot and planting dates as subplots) with three replications in the Agricultural Research Station at Ferdowsi University of Mashhad in 2015–2016. Treatments included: planting times (sub plot factor): (27th of October, 27th of November, 1st of March, 10th of March, and 8th of April) and nutritional sources (main plot factor): (Cow Manure, Chemical Fertilizer, and mixture of Cow Manure + Chemical Fertilizer). The results showed that the anise plant essential oil qualitative characteristics were significantly influenced by treatments. Also, interaction between the fertilizer treatments and planting dates on the essential oil content and concentration of the plants were significant. The highest percentage of plant essential oil (3.71%) was found in the cow manure treatment, and the lowest percentage of essential oil (2.95%) was obtained in the chemical fertilizer. The highest essential oil yield (16.09 kg/ha) was found in the mixed treatment of the cow manure and the chemical fertilizer, and the chemical fertilizer treatment had the lowest rate of essential oil yield (11.41 kg/ha). The highest percentages of the plant oil (14.31%) and the plant oil yield (77.46 kg/ha) were found in the integrated treatment of the cow manure and the chemical fertilizers. The lowest amounts of the plant oil (12.19%) and the plant oil yield (41.28 kg/ha) were found in the chemical fertilizer. According to the percentage and the yield of the essential oil, the best planting time and fertilizer treatment was the one on 10th of March and using integrated cow manure and chemical fertilizer. 相似文献
49.
Roozbeh Mirza Mehdi Mohammadi Ali Dadolahi Sohrab Alireza Safahieh Ahmad Savari Pavaneh Hajeb 《Water, air, and soil pollution》2012,223(1):189-198
The concentration of polycyclic aromatic hydrocarbons (PAHs) was determined in seawater, sediment, and Rock oyster Saccostrea cucullata collected from four sampling sites in the inter-tidal areas of Bushehr province. The total concentrations of 14 PAHs varied
from 1.5 to 3.6 ng/L in seawater, 41.7 to 227.5 ng/g dry weight in surface sediment, and 126 to 226.1 ng/g dry weight in oyster
tissue. In comparing PAH concentrations among the three matrices in Bushehr province, data showed that the pattern of individual
PAHs in seawater, oyster, and sediment were different. The oysters tended to accumulate the lower molecular weight and the
more water-soluble PAHs. Sediment samples were distinguished from the sea water and oyster samples by the presence of high
molecular weight PAHs, especially six-ring PAHs. Three- and four-ring PAHs were the most abundant compounds among the 14 PAHs
investigated in surface seawater, sediment, and oyster samples. As expected, differences in octanol/water partition coefficient
among individual PAHs and the greater persistence of the higher molecular weight PAHs contributed to the accumulation patterns
in oyster and sediment. The results of the study suggested that the main sources of PAHs in the seawater and sediment in the
region were mixed pyrolitic and petrogenic inputs. 相似文献
50.
Alireza Ashori 《Fibers and Polymers》2006,7(1):26-29
Samples of kenaf (Hibiscus cannabinus) grown in Malaysia were examined to determine the kraft pulp and papermaking properties of their bast (or bark) fibers. Using kraft pulping process showed that bast fibers were relatively easy to cook resulting good pulp yields in the range of 45–51%. The bast pulp produced sheets with great density, tear index and dry zero-span breaking length. Kenaf bast fiber is considered promising for production of high-grade printing, writing and specialty papers. 相似文献