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排序方式: 共有222条查询结果,搜索用时 296 毫秒
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.
Asadi Z. Mohammadi M. H. Shorafa M. Farhbakhsh M. Ghezelbash E. 《Eurasian Soil Science》2020,53(6):749-759
Eurasian Soil Science - The objectives of this research are prediction of soil drainage curve using Assouline and Or (2014) adjusted soil drainage model and comparison of the predicted results with... 相似文献
3.
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
4.
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
5.
Construction of a microarray specific to the chicken immune system: profiling gene expression in B cells after lipopolysaccharide stimulation 下载免费PDF全文
Aimie J. Sarson Leah R. Read Hamid R. Haghighi Melissa D. Lambourne Jennifer T. Brisbin Huaijun Zhou Shayan Sharif 《Canadian journal of veterinary research》2007,71(2):108-118
The objective of this study was to profile gene expression in cells of the chicken immune system. A low-density immune-specific microarray was constructed that contained genes with known functions in the chicken immune system, in addition to chicken-expressed sequence tags (ESTs) homologous with mammalian immune system genes, which were systematically characterized by bioinformatic analyses. Genes and ESTs that met the annotation criteria were amplified and placed on a microarray. The microarray contained 84 immune system gene elements. As a means of calibration, the microarray was then used to examine gene expression in chicken B cells after lipopolysaccharide stimulation. Differential gene expression was observed at 6, 12, and 24 h but not at 48 h after stimulation. The results were validated by semiquantitative polymerase chain reaction. The microarray showed a high degree of reproducibility, as demonstrated by intra- and interassay correlation coefficients of 0.97 and 0.95, respectively. Thus, the low-density microarray developed in this study may be used as a tool for monitoring gene expression in the chicken immune system. 相似文献
6.
Kamran Haq Sarah K. Wootton Neda Barjesteh Serguei Golovan Andrew Bendall Shayan Sharif 《Canadian journal of veterinary research》2015,79(1):1-7
Interferon (IFN)-γ has been shown to be associated with immunity to Marek’s disease virus (MDV). The overall objective of this study was to investigate the causal relationship between IFN-γ and vaccine-conferred immunity against MDV in chickens. To this end, 3 small interfering RNAs (siRNAs) targeting chicken IFN-γ, which had previously been shown to reduce IFN-γ expression in vitro, and a control siRNA were selected to generate recombinant avian adeno-associated virus (rAAAV) expressing short-hairpin small interfering RNAs (shRNAs). An MDV challenge trial was then conducted: chickens were vaccinated with herpesvirus of turkey (HVT), administered the rAAAV expressing shRNA, and then challenged with MDV. Tumors were observed in 4 out of 10 birds that were vaccinated with HVT and challenged but did not receive any rAAAV, 5 out of 9 birds that were administered the rAAAV containing IFN-γ shRNA, and 2 out of 10 birds that were administered a control enhanced green fluorescent protein siRNA. There was no significant difference in MDV genome load in the feather follicle epithelium of the birds that were cotreated with the vaccine and the rAAAV compared with the vaccinated MDV-infected birds. These results suggest that AAAV-based vectors can be used for the delivery of shRNA into chicken cells. However, administration of the rAAAV expressing shRNA targeting chicken IFN-γ did not seem to fully abrogate vaccine-induced protection. 相似文献
7.
Amber M. Kameka Siamak Haddadi Fathima Jesreen Jamaldeen Prima Moinul Xiao T. He Fathima Hafsa P. Nawazdeen Stephan Bonfield Shayan Sharif Nico van Rooijen Mohamed Faizal Abdul-Careem 《Canadian journal of veterinary research》2014,78(4):274-282
Macrophages function as phagocytes and antigen-presenting cells in the body. As has been demonstrated in mammals, administration of clodronate [dichloromethylene bisphosphonate (Cl2MBP)] encapsulated liposomes results in depletion of macrophages. Although this compound has been used in chickens, its effectiveness in depleting macrophages has yet to be fully determined. Here, we show that a single administration of clodronate liposomes to chickens results in a significant depletion of macrophages within the spleen and lungs of chickens up to 4 d post-treatment. This finding suggests that, in order to obtain depletion of macrophages in chickens for greater than 5 d, it is necessary to administer clodronate liposomes 4 d apart. The study also showed that 2 treatments of clodronate liposomes at 4-day intervals resulted in the depletion of macrophages for up to 10 d. The findings of the present study will encourage more precise studies to be done on the potential roles of macrophages in immune responses and in the pathogenesis of microbial infections in chickens. 相似文献
8.
A.N.K. Floras M.K. Holowaychuk D. Bienzle A.M.E. Bersenas S. Sharif T. Harvey S.K. Nordone G.A. Wood 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(5):1447-1453
Background
Serum N‐terminal pro‐C‐natriuretic peptide (NT‐proCNP) concentration at hospital admission has sufficient sensitivity and specificity to differentiate naturally occurring sepsis from nonseptic systemic inflammatory response syndrome (SIRS). However, little is known about serum NT‐proCNP concentrations in dogs during the course of sepsis.Objective
To determine serum NT‐proCNP and cytokine kinetics in dogs with endotoxemia, a model of canine sepsis.Samples
Eighty canine serum samples.Methods
Eight healthy adult Beagles were randomized to receive Escherichia coli lipopolysaccharide (LPS, 5 μg/kg) or placebo (0.9% NaCl) as a single IV dose in a randomized crossover study. Serum collected at 0, 1, 2, 4, and 24 hours was stored at −80°C for batch analysis. Serum NT‐proCNP was measured by ELISA and 13 cytokines and chemokines by multiplex magnetic bead‐based assay.Results
Serum NT‐proCNP concentrations did not differ significantly between LPS‐ and placebo‐treated dogs at any time. When comparing serum cytokine concentrations, LPS‐treated dogs had higher interleukin‐6 (IL‐6), IL‐10, TNF‐α and KC‐like at 1, 2, and 4 hours; higher CCL2 at 1, 2, 4, and 24 hours; and higher IL‐8 and CXCL10 at 4 hours compared to placebo‐treated dogs. There were no differences in serum GM‐CSF, IFN‐γ, IL‐2, IL‐7, IL‐15 or IL‐18 between LPS‐ and placebo‐treated dogs.Conclusions and Clinical Importance
Serum NT‐proCNP concentration does not change significantly in response to LPS administration in healthy dogs. Certain serum cytokine and chemokine concentrations are significantly increased within 1–4 hours after LPS administration and warrant further investigation as tools for the detection and management of sepsis in dogs. 相似文献9.
Saiful Izwan Abd Razak Noor Fadzliana Ahmad Sharif Nadirul Hasraf Mat Nayan 《Fibers and Polymers》2014,15(6):1107-1111
This research work reports new electrically conductive paper made of pineapple leaf fiber and polyaniline (PALF/PANI). The conductive paper shows remarkable preservation of mechanical properties while achieving its conductive state. Also it was found that, the amount of PANI needed to achieve the conductivity transformation is as low as 5 wt.%. 相似文献
10.
Karim Sorkheh Behrouz Shiran T. M. Gradziel B. K. Epperson Pedro Martínez-Gómez E. Asadi 《Euphytica》2007,156(3):327-344
Amplified fragment length polymorphism (AFLP) analysis is a rapid and efficient method for producing DNA fingerprints and
molecular characterization. Our objectives were to: estimate genetic similarities (GS), marker indices, and polymorphic information
contents (PICs) for AFLP markers in almond cultivars; assess the genetic diversity of almond cultivars and wild species, using
GS estimated from AFLP fingerprints and molecular characterization; and facilitate the use of markers in inter-specific introgression
and cultivar improvement. The genetic diversity of 45 almond cultivars from Iran, Europe, and America, were studied assaying
19 primer combinations. In addition, several agronomic traits were evaluated, including flowering and maturity times, self-incompatibility,
and kernel and fruit properties. Out of the 813 polymerase chain reaction fragments that were scored, 781 (96.23%) were polymorphic.
GS ranged from 0.5 to 0.96, marker indices ranged from 51.37 to 78.79, and PICs ranged from 0.56 to 0.86. Results allowed
the unique molecular identification of all assayed genotypes. However, the correlation between genetic similarity clustering
as based on AFLP and clustering for agronomic traits was low. Cluster analysis based on AFLP data clearly differentiated the
genotypes and wild species according to their origin and pedigree, whereas, cluster analysis based on agronomic data differentiated
according the pomological characterization. Our results showed the great genetic diversity of the almond cultivars and their
interest for almond breeding. 相似文献