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291.
Mostafa Farhadi Mulualem Tigabu Alireza Ghasemi Arian Mehdi Sharifani Abolfazl Daneshvar Per Christer Oden 《林业研究》2013,24(2):273-278
Acer velutinum Boiss is a valuable tree species native to Iran, and its seeds possess physiological dormancy that hampers seedling production in the nursery for large-scale reforestation efforts. The aim of this study was to determine the optimal dormancy breaking treatments for A. velutinum seeds. We conducted a factorial experiment involving six seed lots collected along an elevation gradient from 300 to 1800 m at 300 m interval and four cold-moist stratification periods (0, 4, 8 and 16 weeks) at 4℃ and 70% relative humidity. The result shows that the germination of cold-moist stratified seeds was significantly (p < 0.0001) higher than the control for all seed lots. The highest germination capacity was recorded after 16 weeks of cold-moist stratification for all seed lots (68% 88% depending on the seed lot) except those collected from mid altitude sites (600 and 900 m) that germinated equally well (≥ 75%) after 4and 8-week of clod-moist stratification compared to the other seed lots. The mean germination time was significantly shorter (12 to 19 days, depending on the seed lot) for seeds stratified for 16 weeks than for untreated seeds. It can be concluded that: (1) cold-moist stratification for 16 weeks is the best pre-sowing treatment for breaking dormancy in A. velutinum seeds; and (2) seeds should be collected from mid altitude sites (600 and 900 m) to get more than 80% germination within 15 days, and these seed lots even required shorter cold-moist stratification period(eight weeks) than other seed lots. 相似文献
292.
Ebrahimi G Ouraji H Khalesi MK Sudagar M Barari A Zarei Dangesaraki M Jani Khalili KH 《Journal of animal physiology and animal nutrition》2012,96(4):591-599
This study evaluated the effects of a commercial prebiotic, Immunogen, on feed utilization, growth rate, immunity promotion and carcass composition of the common carp Cyprinus carpio fingerlings. The fingerlings were adopted for 2 weeks and then reared in triplicate groups in 250-l tanks (n = 15 per tank with average initial weights of 11.12 ± 0.55 g). The fish fed on five isonitrogenous and isoenergetic experimental diets containing different levels of Immunogen (0, 0.5, 1, 1.5 and 2.5 g prebiotic/kg diet) to apparent satiation thrice a day for 8 weeks. Weight gain showed no differences among the groups fed different Immunogen levels. Both feed efficiency ratio and protein efficiency ratio significantly (p < 0.05) increased with increasing Immunogen levels from 0.5 to 1.5 g/kg diet. The highest protein content (p < 0.05) was found in the fish fed a diet containing 2.5 g/kg prebiotic. Haematological parameters and plasma total protein concentration were also significantly higher (p < 0.05) in the fingerlings fed diets containing 1.5 and 2.5 g/kg prebiotic in relation to the control. The control fish contained the highest mean of total bacterial counts. The lowest mean (p < 0.05) of total bacterial counts was observed in the fish fed the diet containing 2.5 g/kg Immunogen. The present study reveals that a dietary Immunogen supplementation from 1 to 1.5 g/kg is capable to improve the feed efficiency and growth performance of C. carpio fingerlings as well as their resistance to A. hydrophila infection. 相似文献
293.
Blaser M Bertagnoli A Räber M Nuss K Rasekh M Steiner A 《Veterinary journal (London, England : 1997)》2012,193(3):701-706
The objective of the present study was to describe the arthroscopic anatomy of the bovine fetlock joint using one palmar/plantar and three dorsal joint approaches. A comparative anatomic, ultrasonographic and arthroscopic study using 20 cadaveric feet from 13 non-lame adult dairy cows was performed. Arthroscopy was accomplished using a rigid arthroscope to view the synovial cavities with their synovial villi and parts of the following structures: the distal ends of the metacarpal/metatarsal III/IV bones with their trochleae and sagittal ridges, synovial grooves, the articular surfaces of the proximal sesamoid bones, the proximal aspects of the first phalanges, the lateral and medial collateral ligaments, the suspensory ligament and the interdigital ligaments as parts of the interosseus muscle, the cruciate sesamoidean ligaments, the communication site between the lateral and medial pouch in the palmar/plantar area, and dorsally the septum between the lateral and the medial pouch. The technique allowed a good overall view of most relevant structures in the sound cadaver joint. Further investigations are warranted to evaluate the diagnostic, therapeutic and prognostic applications of these techniques in the treatment of septic arthritis. 相似文献
294.
Sadegh Maleki Akbar Rostampsour Haftkhani Mosayeb Dalvand Mehdi Faezipour Mehdi Tajvidi 《林业研究》2012,23(3):481-490
We determined the effects of the penetration depth and spline material and composite material type as well as joining method on bending moment resistance under diagonal compression and tension in common wood panel structures. Composite materials were laminated medium density fiberboard (MDF) and particle board. Joining methods were buttand miter types. Spline materials were high density fiber board (HDF).The penetration depths of plywood, wood (Carpinus betolus) and splinewere 8, 11 and 14 mm. The results showed that in both diagonal compression and tension, MDF joints are stronger than particle board joints,and the bending moment resistance under compression is higher compared with that in tension. The highest bending moment resistance under tension was shown in MDF, butt joined using plywood spline with 8 mm penetration depth, whereas under compression bending moment resistance was seen in MDF, miter joined with the HDF spline of 14 mm penetration depth. 相似文献
295.
296.
Seyed Pezhman Hosseini Shekarabi Mehdi Shamsaie Mehrgan Akbar Banavreh Farhad Foroudi 《Aquaculture Research》2021,52(1):249-259
An 8‐week feeding trial was run to investigate the replacement of fishmeal with corn protein concentrate (CPC; Empyreal®) in rainbow trou (100.5 ± 2.3 g) diet. Fishmeal was increasingly replaced with 0 (Control), 30 (CPC3), 60 (CPC6), 90 (CPC9) and 120 (CPC12) g/kg CPC. The results showed that the substitution of fishmeal with CPC up to 90 g/kg did not cause significant differences in the growth indices as compared to the control group, while further replacement resulted in the reduction of the growth performance. The fillet crude protein showed no significant difference between the control diet and diets containing up to 90 g/kg CPC (p > .05). Serum biochemical parameters such as albumin and glucose did not change notably, while the highest levels of alanine aminotransferase and lactate dehydrogenase were seen in the CPC12 group (p < .05). Also, serum lysozyme activity was increased with the elevation of dietary CPC up to 90 g/kg (p < .05). The redness and yellowness of the fillet were markedly elevated with the dietary incorporation of CPC (p < .05). Taken together, the optimum range of fishmeal substitution with CPC was 81.0–82.2 g/kg CPC in rainbow diet based on the broken‐line regression analysis. 相似文献
297.
Colloidal stability in some tropical soils of southeastern Nigeria as affected by iron and aluminium oxides 总被引:2,自引:0,他引:2
The stability of microaggregates in soils as opposed to its dispersion is a very important soil phenomenon that checks degradation arising from unguided tillage and soil erosion. Ten soils from southeastern Nigeria were sampled from their typical A and B horizons for the study. The aim was to identify the extent of colloidal stability of the soils and the forms of Fe and Al oxides in the soils contributing to their stability. The soils are mostly Ultisols and Inceptisols formed on sandstones and shale parent materials. The soils are low in soil basic cations including the soil organic carbon (SOC). The major clay mineral is kaolinite while the soil is acid in reaction. The various forms of soil Fe and Al oxides are high with the total forms of Fe and Al being most dominant and > dithionite extracted Fe and Al > oxalate extracted Fe and Al > pyrophosphate extracted Fe and Al. The water-dispersible clay and silt (WDC) and (WDSi) which are index of dispersion in most soils are low to medium thus reflecting in the low to medium dispersion ratio (DR). The clay flocculation index (CFI) and aggregated silt + clay (ASC) were moderate to high implying the high potential stability of the soils. Soil organic carbon did not seem to be contributing much to the stability of the microaggregates while oxalate and pyrophosphate extractable Fe (Feox, Fep) and to some extent total Al (Alt) were among the different forms of oxides that act as aggregating agents. We propose here that rather than SOC acting as a disaggregating agent in the soils, it might have acted in association with these oxides in a linkage or bridge such as C–P–OM–C to ensure stability of the soils. 相似文献
298.
Mehdi Alikhani Samaneh Saberi Maryam Esmaeili Valrie Michel Mohammad Tashakoripour Afshin Abdirad Arezoo Aghakhani Sana Eybpoosh Massoud Vosough Mohammad Ali Mohagheghi Mahmoud Eshagh Hosseini Eliette Touati Marjan Mohammadi 《Iranian Biomedical Journal》2021,25(5):323
Background:Variations in mtDNA-CN of PBLs, as a potential biomarker for GC screening has currently been subject to controversy. Herein, we have assessed its efficiency in GC screening, in parallel and in combination with sPG I/II ratio, as an established indicator of gastric atrophy. Methods:The study population included GC (n = 53) and non-GC (n = 207) dyspeptic patients. The non-GC group was histologically categorized into CG (n = 104) and NM (n = 103) subgroups. The MtDNA-CN of PBLs was measured by quantitative real-time PCR. The sPG I and II levels and anti-H. pylori serum IgG were measured by ELISA. Results:The mtDNA-CN was found significantly higher in GC vs. non-GC (OR = 3.0; 95% CI = 1.4, 6.4) subjects. Conversely, GC patients had significantly lower sPG I/II ratio than the non-GC (OR = 3.2; CI = 1.4, 7.2) subjects. The combination of these two biomarkers yielded a dramatic amplification of the odds of GC risk in double-positive (high mtDNA-CN-low sPGI/II) subjects, in reference to double-negatives (low mtDNA-CN-high sPGI/II), when assessed against non-GC (OR = 27.1; CI = 5.0, 147.3), CG (OR = 13.1; CI = 2.4, 72.6), or NM (OR = 49.5; CI = 7.9, 311.6) groups. Conclusion:The combination of these two biomarkers, namely mtDNA-CN in PBLs and serum PG I/II ratio, drastically enhanced the efficiency of GC risk assessment, which calls for further validations. Key Words: Biomarkers, DNA copy number variation, Mitochondrial DNA, Stomach neoplasms 相似文献
299.
Mehdi Hosseini Farahi Bahman Kholdebarin Saeid Eshghi Babak Jamali 《Journal of plant nutrition》2019,42(9):1047-1060
The aim of this study was to investigate the biochemical responses and vase life of rose cut flowers under different ratios of NO3:NH4:urea in soilless culture. In this study, urea was used as the source of nitrogen (N) in solution cultures. For this purpose, an experiment was conducted as completely randomized design with seven ratios of N forms and three replications. The rooted cuttings of rose cv Dolce Vita were supplied with seven different ratios of NO3?:NH4+:urea (100:0:0, 70:15:15, 50:25:25, 50:0:50, 0:0:100, 50:50:0 and 0:100:0). Results showed that with the increase in urea and ammonium concentrations, the amounts of cuttings IAA, GA3, zeatin, ABA and polyamines contents decreased significantly. Plants fertigated with nutrient solution containing NO3?:NH4+:urea (50:25:25) had the highest concentrations of growth regulators, the highest stalk length and flower vase life. As the ammonium ratios in the nutrient solution increased, the flower vase life decreased significantly. It was concluded that using NO3?:NH4+:urea at the ratio of 50:25:25 had the highest effects on improving the rose cut flowers quality by affecting plants growth regulators and can be recommended for cut rose production in soilless culture systems. 相似文献
300.
Hygroscopic thickness swelling rate of composites from sawdust and recycled plastics 总被引:1,自引:1,他引:0
Saeed Kazemi Najafi Azadeh Kiaeifar Mehdi Tajvidi Elham Hamidinia 《Wood Science and Technology》2008,42(2):161-168
The thickness swelling rates of compression molded wood plastic composites (WPCs) prepared from 50% by weight sawdust and
50% by weight virgin and/or recycled plastics (HDPE and PP) were studied. Thickness swelling rates of the manufactured WPCs
were evaluated by immersing them in water at room temperature and monitoring thickness changes for several weeks. A swelling
model developed by Shi and Gardner (Composites Part A, 37:1276–1285, 2006) was used to study the thickness swelling process
of WPCs. The parameter K
SR of the model can be used to quantify the swelling rate. The results indicated that composites containing PP had lower equilibrium
thickness swelling and also shorter equilibrium time (time to reach equilibrium thickness swelling). The swelling model developed
was a good predictor of the hygroscopic swelling process of wood plastic composites. Composites containing PP (virgin and
recycled) had higher K
SR than those containing HDPE. The minimum and maximum K
SR values were observed in composites made of virgin HDPE and a mixture of recycled plastics, respectively. With increasing
recycled plastic content K
SR linearly decreased. 相似文献