排序方式： 共有26条查询结果，搜索用时 343 毫秒
11.
We have employed both common and novel methods to measure the amount of silver released from nanoparticle composite packaging. Forty-eight packages of green tiger prawns (Penaeus semisulcatus) were prepared: 24 packages with nanoparticle packaging and 24 packages without nanoparticle packaging. The normal shelf life of P. semisulcatus in the refrigerator is 1–2 days, and we therefore we tested the packages after 0, 1, 2, 3, 4, 5 and 6 days. We measured the diameter of the inhibition zone of the targeted microorganisms (Escherichia coli and Staphylococcus aureus) and examined scanning electron microscopy (SEM) images, using both titration and migration methods, to measure the amounts of silver nanoparticles released. Compared to the standard amount allowed by standard 13737-3 of the National Information Standards Organization, our results indicated the superior sensitivity of the titration method over the migration method in terms of determining the remaining amount of nanoparticles (P < 0.05). The evaluation of SEM images indicated the homogeneity of the surface of the silver nanoparticle packaging and the even exchange capacity of titanium dioxide. The average size of the nanoparticles in the packaging films was determined to be 30–48 nm. The diameter of the inhibition zone in the silver nanoparticle, measured at the six time points, was significantly larger than that seen with other packaging, except for the phosphomycin and penicillin antibiogram disks (P < 0.01). The sensitivity of the titration method using the titration equipment was significantly higher than that of the migration method (P < 0.05). The findings indicate that nanoparticle packaging decreased the microbial count and enhanced the shelf life of P. semisulcatus, leading us to recommend the utilization of silver nanoparticle packaging. 相似文献
12.
This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length （CGL） and cooked grain shape （CGSH）. General combining ability （GCA） and specific combining ability （SCA） effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index （GEI）. In the controlling of the inheritance of milled grain shape （GSH）, milled grain width （MGW）, GEI, milled grain length （MGL）, CGSH and cooked grain width （CGW）, the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 （GSH） to 0.36 （CGL）. GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits. 相似文献
13.
This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one.The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits. 相似文献
14.
Jo-Anne E. Cavanagh Peyman Zawar-Reza J. Gaines Wilson 《Urban Forestry & Urban Greening》2009,8(1):21-30
Of interest to researchers and urban planners is the effect of urban forests on concentrations of ambient air pollution. Although estimates of the attenuation effect of urban vegetation on levels of air pollution have been put forward, there have been few monitored data on small-scale changes within forests, especially in urban forest patches. This study explores the spatial attenuation of particulate matter air pollution less than 10 μ in diameter (PM10) within the confines of an evergreen broadleaved urban forest patch in Christchurch, New Zealand, a city with high levels of PM10 winter air pollution. The monitoring network consisted of eight monitoring sites at various distances from the edge of the canopy and was operated on 13 winter nights when conditions were conducive for high pollution events. A negative gradient of particulate concentration was found, moving from higher mean PM10 concentrations outside the forest (mean=31.5 μg m?3) to lower concentrations deep within the forest (mean=22.4 μg m?3). A mixed-effects model applied to monitor meteorological, spatial and pollution data indicated temperature and an interaction between wind speed and temperature were also significant (P?0.05) predictors of particulate concentration. These results provide evidence of the potential role that urban forest patches may play in mitigating particulate matter air pollution and should be considered in plans for improving urban air quality. 相似文献
15.
Journal of Crop Science and Biotechnology - It is of special importance to track the fertility restoring alleles in plants such as sugar beet in which cytoplasmic male sterility (CMS) is used to... 相似文献
16.
Using sequential Gaussian simulation to assess the field-scale spatial uncertainty of soil water content 总被引：1，自引：0，他引：1
Soil water content (SWC) has a vital role in a variety of hydrological processes such as infiltration, runoff and erosion. Mapping the spatial pattern of SWC is then essential for appropriate addressing of these processes. Geostatistics is often used to characterize the spatial variability of SWC. This information may be used for estimating SWC e.g., by ordinary kriging (OK) or modeling location-specific uncertainty (local uncertainty) of the estimates by indicator kriging (IK). Kriging-based algorithms however smooth out the details and are incapable of detecting multi-location uncertainty (spatial uncertainty) of SWC estimates. Sequential Gaussian simulation (sGs) can model the spatial uncertainty through generation of several equally probable stochastic realizations. In this study sGs is used to map SWC spatial distribution and to provide a quantitative measure of its spatial uncertainty in particular. The SWC measurements were performed on 157 soil samples taken from an 18 ha erosion experiment field in Lower Austria. The results show that the spatial pattern of SWC is well recognized using the sGs as the simulated models reproduce the sample statistics including histogram and semivariogram model reasonably well. The difference among realizations is used to provide a quantitative measure of spatial uncertainty of SWC estimates. Knowledge of spatial uncertainty is helpful to evaluate the delineation of vulnerable areas to erosion. 相似文献
17.
Choi M Scholl UI Yue P Björklund P Zhao B Nelson-Williams C Ji W Cho Y Patel A Men CJ Lolis E Wisgerhof MV Geller DS Mane S Hellman P Westin G Åkerström G Wang W Carling T Lifton RP 《Science (New York, N.Y.)》2011,331(6018):768-772
Endocrine tumors such as aldosterone-producing adrenal adenomas (APAs), a cause of severe hypertension, feature constitutive hormone production and unrestrained cell proliferation; the mechanisms linking these events are unknown. We identify two recurrent somatic mutations in and near the selectivity filter of the potassium (K(+)) channel KCNJ5 that are present in 8 of 22 human APAs studied. Both produce increased sodium (Na(+)) conductance and cell depolarization, which in adrenal glomerulosa cells produces calcium (Ca(2+)) entry, the signal for aldosterone production and cell proliferation. Similarly, we identify an inherited KCNJ5 mutation that produces increased Na(+) conductance in a Mendelian form of severe aldosteronism and massive bilateral adrenal hyperplasia. These findings explain pathogenesis in a subset of patients with severe hypertension and implicate loss of K(+) channel selectivity in constitutive cell proliferation and hormone production. 相似文献
18.
Karimi Vahid Mohammadi Peyman Ghalyanchilangeroudi Arash Ghafouri Seyed Ali Hashemzadeh Masoud Farahani Reza Khaltabadi Maghsouldoo Hussein Isakakroudi Nima 《Tropical animal health and production》2019,51(3):629-635
Tropical Animal Health and Production - Infectious bronchitis virus (IBV) is a highly infectious pathogen, which affects the respiratory tract, reproductive system, and kidney of chickens. Many... 相似文献
19.
Izadyar Nasrin Abd Nikfarjam Bahareh Esmaeili Rastaghi Ahmad Reza Alizadeh Safar Ali Heydarian Peyman Saraei Mehrzad 《Tropical animal health and production》2019,51(5):1289-1293
Background
Toxoplasma gondii is a common protozoan parasite among all mammals, in particular small ruminants, worldwide. Traditional husbandry can be a major risk factor for infection of sheep and goats with this parasite.
ObjectivesThe present study aimed to determine the current status of the prevalence for T. gondii in livestock of Qazvin Province.
MethodsIn this cross-sectional study, the sera of 455 sheep and 375 goats were examined to detect anti-Toxoplasma IgG antibodies by using in-house indirect ELISA.
ResultsOverall, 33.62% (153/455) of sheep and 36.41% (130/375) of goats were positive for anti-Toxoplasma IgG antibodies with no statistically significant difference. The prevalence rate of T. gondii among the sheep of Qazvin County was significantly higher than in Abyek and Abhar counties (p < 0.001).
ConclusionsThe results of the present study indicate that the prevalence of T. gondii in sheep and goats of the study area is high. Therefore, the meat of the animals reared in this area can be a potential source of human infections by this parasite.
相似文献20.
Peyman Eynipour Morteza Chaji Mohsen Sari 《Journal of animal physiology and animal nutrition》2019,103(6):1708-1718
The aim of the experiment was to investigate the replacement value of common bean residues in the diet of finishing lambs as an inexpensive fodder instead of wheat straw or maize silage. Forty Arabi male lambs with average body weight of 18.90 ± 0.6 kg were randomly divided into five treatments with eight replications. The five experimental treatments consisted of control diet, and 50% and 100% replacement of bean residues with wheat straw or 25% and 50% replacement with maize silage in the control diet respectively. Lambs were slaughtered at the end of the experiment to evaluate carcass traits and meat characteristics. Dry matter intake, blood glucose, urea nitrogen, cholesterol and triglyceride concentration were not affected by the experimental treatments. Apparent digestibility of nutrients; total concentration of volatile fatty acids, acetate and butyrate; and total rumen protozoa population were linearly increased by increasing the levels of bean residues, as replacement with wheat straw (p < .05). Replacement of bean residues in control diets instead of wheat straw or maize silage caused a positive linear incremental trend for average daily gain and total weight gain. There was no significant difference in daily gain, final weight and feed conversion ratio among the treatments. Instead of wheat straw or maize silage, replacement bean residues linearly increased chewing, ruminating and eating activities per neutral detergent fibre intake (p < .05). Carcass traits and physicochemical characteristics of meat were not affected by the treatments. It is advisable to use bean residues in the diet of lambs as an alternative to the wheat straw or maize silage, because no adverse effects were observed on rumen fermentation, blood metabolites and performance; moreover, improvement in average daily gain, total weight gain and digestibility of nutrients, and the fact that bean residue is less expensive than wheat straw and maize silage. 相似文献