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1.
Sodium adsorption ratio (SAR) is one of the water quality indexes that whose is important due to reuse or depletion to environment. Solutes in drain water can be controlled by adsorption, chemical or biological reaction, organic envelope of drainage. Rice husk is the common option of drainage envelops in paddy fields. In this study, the ability of reduction of SAR by rice husk was evaluated in batch scale and physical model of drain envelops. In the batch experiments, the adsorption of SAR parameters was investigated by adding 2 g of rice husk into a 100 ml of sodium chloride solution. The results indicated that rice husk absorbed calcium, magnesium and sodium, respectively. By increasing the temperature, contact time and pH, adsorption of calcium, magnesium and sodium was increased; however, the higher concentration of sodium in soil solution reduced the percentage of adsorption. In a more realistic state, physical models of subsurface drainage in the paddy fields were made. Drainage envelope treatments included of rice husk (H), combination of 20 and 60 % of husk with gravel (H20G80 and H60G40) and a pipe without envelope (NE). Due to higher drain discharge and more sodium removal (lower SAR in drain water), treatment H with the discharge of 16.2 ml/min and SAR of 1.27 (meq/l)0.5 was better in comparison with other treatments. 相似文献
2.
Ehsan Sabertanha Yousef Rouzbehan Hassan Fazaeli Javad Rezaei 《Journal of animal physiology and animal nutrition》2021,105(6):1034-1045
This study compared ensiled sorghum (ES) from two varieties (first and second cuts) with corn silage (CS) for chemical analysis, total-tract nutrient digestibility, ruminal variables and blood biochemistry metabolites in sheep. Five experimental silages representing first cut ES var. Pegah (PS1), second cut ES var. Pegah (PS2), first cut ES var. Speedfeed (SS1), second cut ES var. Speedfeed (SS2) and CS were assessed for chemical analysis, silage fermentation and anti-quality compounds. Diets consisted of lucerne hay, silage and a premix (at the ratio of 53.5:46:0.5 on a dry matter [DM] basis). Feed consumption, total-tract nutrient digestibility, microbial nitrogen supply (MNS), ruminal variables and blood biochemistry metabolites were determined in a Latin square design of five periods with five male sheep. Compared to sorghum, CS had lower (p < 0.01) concentrations of ash, water-soluble carbohydrates and crude protein, but higher starch, lignin (sa), non-structural carbohydrates and apparent nutrient digestibility. The measurements of pH, lactic acid, NH3-N and volatile fatty acids (VFA) confirmed that all silages were well-preserved. The anti-quality compound levels in the silages were below the safe limits for ruminants. No differences were observed in feed consumption (p > 0.05) and total-tract digestibility of DM and nutrients (p > 0.05). Rumen pH, NH3-N, VFA concentrations and acetate to propionate ratio showed no difference among treatments (p > 0.05). Sheep fed on sorghum silage showed a decrease (p < 0.01) in total protozoa, and particularly in the Entodiniae population. There were no differences in cellulolytic bacteria counts (p > 0.05) among treatments. Urinary N, MNS and blood biochemistry metabolites showed no difference among treatments (p > 0.05). Silages from both cuts of sorghum had comparable total-tract nutrient digestibility to CS, therefore, these varieties could be used as a more drought resilient silage source in the feeding of sheep. 相似文献
3.
Moqanaki Ehsan M. Milleret Cyril Tourani Mahdieh Dupont Pierre Bischof Richard 《Landscape Ecology》2021,36(10):2879-2895
Landscape Ecology - Spatial capture-recapture (SCR) models are increasingly popular for analyzing wildlife monitoring data. SCR can account for spatial heterogeneity in detection that arises from... 相似文献
4.
Bone marrow samples were collected from the ribs of 20 healthy adult male Iranian camels (Camelus dromedarius). The bone marrow smears were stained using Wright's stain. Blood samples were collected at the same time for routine haematological examination. The development and morphology of the blood cells in the bone marrow of the camels were similar to those of other domestic species. The mean myeloid/erythroid ratio was 1.21, the mean erythroid percentage was 42.7% and the mean myeloid percentage was 52.0%. The mean percentage of other cells was 5.3%. The mean percentage of eosinophils in the myeloid series was higher than in other domestic species. Iron stores, estimated from Perl's stain, ranged from scant (1+) to moderate (3+) but most samples had 2+ iron content. All peripheral blood results were within reference ranges. 相似文献
5.
Amer Ibrahim Basha Stefano Padulosi Kamel Chabane Adnan Hadj-Hassan Ehsan Dulloo Mario Augusto Pagnotta Enrico Porceddu 《Genetic Resources and Crop Evolution》2007,54(8):1807-1816
Pistachio (Pistacia vera L.) is a strategic nut tree species in the Middle East which holds comparative advantage over other fruit trees in view of
its hardiness, income generation opportunities and benefits for the ecosystem. Yet pistachio cultivation depends on a very
narrow genetic base, in spite of the existence of many varieties still marginally exploited. Syria is an important center
of diversity for pistachio. A country wide ecogeographic survey in this country was carried out to determine the extent of
pistachio genetic diversity and its use. As a whole, 114 accessions were collected from 37 farms to assess diversity at morphological
and molecular level. Molecular evaluation was carried out using Amplified Fragment Length Polymorphism (AFLP) technique and
performed using seven primer pair combinations. Results from the studies allowed the identification of 25 pistachio female
varieties in Syria, some of which unique and described for the first time. Three groups of pistachio diversity were identified
by cluster analysis which provides useful information about the distribution of genetic diversity in Syria for enhanced use
and sustainable conservation. 相似文献
6.
Ehsan Arya KolaeiRussell J. Tweddell Tyler J. Avis 《Postharvest Biology and Technology》2012,63(1):55-59
In the search for alternatives to synthetic fungicides to control postharvest disease, sulfur-containing salts were evaluated for their effects on the mycelial growth of various fungal or fungus-like pathogens and their ability to control carrot cavity spot (Pythium sulcatum) and potato dry rot (Fusarium sambucinum). Results showed that metabisulfite-containing salts provided strong inhibition of all the tested fungi. Furthermore, some sulfate-containing salts were also directly inhibitory to P. sulcatum (calcium sulfate and ammonium sulfate) and to F. sambucinum (sodium sulfate). The metabisulfite salts also provided 100% inhibition of cavity spot and dry rot at concentrations of 50 and 200 mM, respectively. Calcium sulfate and sodium sulfate also significantly reduced carrot cavity spot lesions at 50 mM and ammonium sulfate, magnesium sulfate, potassium sulfate and sodium sulfate reduced potato dry rot lesions at 200 mM. These results indicate that various sulfate and metabisulfite salts could be used to control these postharvest microorganisms. 相似文献
7.
Hashemnia M Khodakaram-Tafti A Razavi SM Nazifi S 《Veterinary research communications》2012,36(1):47-55
The progressive morphohistopathologic changes, distribution pattern of lesions and ultrastructural characteristics in Eimeria arloingi infection were investigated in experimentally infected kids. The 18 newborn animals allocated to 3 equal groups. Two of groups,
A, B were inoculated with a single dose of 1 × 103 and1 × 105 sporulated oocysts of E. arloingi, respectively. At 7, 14, 21, 28, 35, and 42 days postinoculation (DPI), 1 kid from each group was necropsied for pathologic
and ultrastructural studies. Progressive lesions were present at 21, 28, 35 and 42 DPI in the jejunum, ileum, cecum with fewer
in the duodenum and proximal colon. The oocysts shedding begin between 16 to 18 DPI. Grossly, minimal changes were observed
at 21 DPI as few whitish plaques or nodules and advanced lesions at 42 DPI as pseudoadenomatous pattern in the mucosa and
a cerebriform pattern on the serosal surface of jejunum and ileum. Early histopathologic lesions due to schizogony phase were
including presence of intracytoplasmic developmental stages of the parasite such as trophozoites, immature to mature schizonts
and mild infiltration of inflammatory cells. In late lesions due to various stages of gametogony, the histological pattern
was mainly remarkable hyperplasia of the villi and crypts epithelial cells, eventually developed into papillary projections
of reactive epithelium. The mesenteric lymph nodes showed a few numbers of large schizonts in the cortical lacteals. This
study showed E. arloingi as a highly pathogenic species for kids, the incubation period was 16–18 days and the main target organ was jejunum with
characteristic morphohistopathologic lesions. 相似文献
8.
Glycosylated Porphyra-334 and Palythine-Threonine from the Terrestrial Cyanobacterium Nostoc commune
Ehsan Nazifi Naoki Wada Minami Yamaba Tomoya Asano Takumi Nishiuchi Seiichi Matsugo Toshio Sakamoto 《Marine drugs》2013,11(9):3124-3154
Mycosporine-like amino acids (MAAs) are water-soluble UV-absorbing pigments, and structurally different MAAs have been identified in eukaryotic algae and cyanobacteria. In this study novel glycosylated MAAs were found in the terrestrial cyanobacterium Nostoc commune (N. commune). An MAA with an absorption maximum at 334 nm was identified as a hexose-bound porphyra-334 derivative with a molecular mass of 508 Da. Another MAA with an absorption maximum at 322 nm was identified as a two hexose-bound palythine-threonine derivative with a molecular mass of 612 Da. These purified MAAs have radical scavenging activities in vitro, which suggests multifunctional roles as sunscreens and antioxidants. The 612-Da MAA accounted for approximately 60% of the total MAAs and contributed approximately 20% of the total radical scavenging activities in a water extract, indicating that it is the major water-soluble UV-protectant and radical scavenger component. The hexose-bound porphyra-334 derivative and the glycosylated palythine-threonine derivatives were found in a specific genotype of N. commune, suggesting that glycosylated MAA patterns could be a chemotaxonomic marker for the characterization of the morphologically indistinguishable N. commune. The glycosylation of porphyra-334 and palythine-threonine in N. commune suggests a unique adaptation for terrestrial environments that are drastically fluctuating in comparison to stable aquatic environments. 相似文献
9.
Efficacy of 1?mM humic (HA) and salicylic (SC) acids on SC 260 and SC 705 corn seedlings to alleviate drought stress via polyethylene glycol was studied via hydroponics at Shiraz University, Iran in a factorial, randomized design, with four replicates each. Under stress, SC 260 had higher electrolyte leakage compared to SC 705, and exogenous application of HA combined with SA decreased SC 705 electrolyte leakage. As a general trend, photosynthetic pigment content, relative water content, root and shoot length, mean number and diameter of central and peripheral root metaxylem, and K+ accumulation were higher in SC 705 treated with HA and SA compared to SC 260. Application of HA with SA could be an effective and low cost approach to ensure seedling establishment and plant growth in fields affected by soil drought in the early season, especially for the SC 705 corn hybrid in semi-arid regions. 相似文献
10.
A 2-year field experiment using a randomized complete block design with the treatments arranged as split-split-plot with three replicates was conducted to investigate the effects of different sowing dates. Different irrigation regimes and different triticale cultivars were tested during 2014 and 2015 growing seasons. Under cutting off irrigation at the milk development stage, Sanabad with 46.2% had higher relative water content on December 3 sowing date. Assimilate remobilization in cutting off irrigation at dough development was more than that at milk development and Sanabad had the highest assimilate remobilization on 3 December sowing date in both years. In both years, Sanabad had the highest remobilization efficiency. The highest contribution of pre-anthesis assimilates to grain was obtained on 3 December sowing date in both years in Sanabad. Lower grain yield in Juanillo cultivar under cutting off irrigation, appeared to be due to reduction in remobilization efficiency, especially by cutting off irrigation at milk development stage in late sowing date. Overall, Sanabad was more tolerant to cutting off irrigation than Juanillo. 相似文献