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101.
Seyed Fakhreddin Hosseini Mojgan Zandi Farhid Farahmand Ghavi 《Journal Of Aquatic Food Product Technology》2013,22(6):835-842
ABSTRACTIn the present study, the effect of fish gelatin coating (FG; 4%, w/v) containing oregano (Origanum vulgare L.) essential oil (OEO; 1.2% w/v) on shelf-life extension of rainbow trout (Oncorhynchus mykiss) fillet stored under refrigerated storage (4 ± 1ºC) was investigated. The control and the treated fish samples were analyzed periodically for chemical (pH; total volatile basic nitrogen, TVB-N; peroxide value, PV; thiobarbituric acid, TBA) and microbiological (total viable count, TVC; psychrotrophic count) characteristics. The FG + OEO treatment produced significantly lower (p < 0.05) TVB-N values as compared to control and FG-coated samples after Day 6 and until the end of the storage period. The TBA values remained low and were found to fluctuate during storage. Results showed that TVC exceeded 6 log CFU g?1 on Day 8 of storage for control and FG-coated samples and Day 12 for samples coated with FG + OEO. The reduction of 1.05 and 0.83 log CFU g?1 of psychrotrophic counts was achieved by FG + OEO coating in trout fillet (p < 0.05) as compared with control and FG-coated samples, respectively. Therefore, the incorporation of OEO into FG coating may be a promising method of maintaining the storage quality of the rainbow trout fillet stored at refrigerated temperature. 相似文献
102.
Reza Hosseini Nhu D. Le James V. Zidek 《Journal of Agricultural, Biological & Environmental Statistics》2012,17(2):283-305
This paper uses high-order categorical non-stationary Markov chains to model the occurrence of extreme temperature events, in particular frost days. These models can be applied to estimate: the probability that a given day in the future is a frost day (below zero); the probability that a given period is frost-free; the distribution of the length of the frost-free period. These quantities then can be used for pricing of weather derivatives. Several stationary and non-stationary high-order (yet parsimonious) Markov models are proposed and compared using AIC and BIC. Partial likelihood theory is used to estimate the parameters of these models. We show that optimal (in terms of AIC/BIC) non-stationary Markov models that have constant ??Markov coefficients?? (across the year) are not adequate to estimate the aforementioned probabilities. Therefore this paper develops Markov models with a time-varying periodic structure across the year. A challenge in fitting these models (by maximizing the partial likelihood) is the large number of parameters. The paper presents a method for overcoming this challenge; one that uses parametric fits to the logit of the nonparametric estimates of the seasonal transition probability curves to initialize the optim function in the R package. Satisfactory results are shown to obtain from this approach. The work is applied to temperature records for the Province of Alberta, Canada. 相似文献
103.
104.
Mohammad-Reza Sarookhani Elmira Ghasemi-Dashkhasan Nima Heidari-Oranjaghi Hassan Azhdari-Zarmehri Elaheh Erami Sedighe-Sadat Hosseini 《Iranian Biomedical Journal》2014,18(2):107-113
Background: The present study examined the possible role of endogenous opioidergic system in effect of food deprivation on formalin-induced nociceptive behaviors in male and female rats. Also, we investigated the effect of food deprivation on the plasma level of beta-endorphin and sex hormones. Methods: Food was withdrawn 48 h prior to performing the formalin test, but water continued to be available ad libitum. The formalin was injected into hind plantar paw. Results: There is significant difference between male and female control rats during phase 2B. Following 48-h food deprivation, both male and female rats exhibited enhanced nociceptive behavior in response to formalin. Food deprivation for 12 and 24 h increased and for 48 h decreased beta-endorphin level in male and female rats. Food deprivation for 24 h decreased testosterone level in male, while it had no significant effect on female rats and food deprivation for 48 h decreased testosterone level in both sexes. Food deprivation for 24 h increased estradiol level in female and that for 48 h had no significant effect on male and female rats. Conclusions: The present study demonstrates the existence of food deprivation for 48 h causes enhancement of nociception in the formalin test in male and female rats that has correlation with decrease in plasma beta-endorphin and testosterone levels. Key Words: Rat, Food Deprivation, beta-endorphin, Naloxone 相似文献
105.
The city of Tehran,like many polluted metropolises of the world,has higher emissions of greenhouse gases than other cities in Iran,due to heavy consumption of fossil fuel and landuse changes.To estimate carbon sequestration in two 40 year-old stands of planted Cupressus arizonica and Fraxinus rotundifolia in degraded lands surrounding Tehran,sampling of above-and below-ground biomass,soil(at two depths of 0-15 and 15-30 cm),and leaf litter was done by systematic random sampling.The total carbon stocks of C.arizonica and F.rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1.The aboveground biomass with 233.16(71%)Mg·ha-1 in C.arizonica and88.16(58.50%)Mg·ha-1 in F.rotundifolia contributed the most shares to carbon sequestration.The diameter at breast height,total height,basal area,total volume,and biomass of C.arizonica were significantly(p0.01)higher than those of F.rotundifolia.Also the depth of 0-30 cm of soil contributed between 18.29%and 32.15%of total ecosystem carbon,respectively.The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars,respectively.Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land,the current status quo.These stands can absorb atmospheric CO2 at different rates,thus tree species selection and stand development should be considered in planning future afforestation projects. 相似文献
106.
Farrar Michael B. Wallace Helen M. Xu Cheng-Yuan Joseph Stephen Dunn Peter K. Nguyen Thi Thu Nhan Bai Shahla Hosseini 《Journal of Soils and Sediments》2021,21(2):784-798
Journal of Soils and Sediments - Biochar can improve soil nutrient retention and alleviate salinity; however, use is not widespread due to cost. Biochar is usually co-applied with a full-rate of... 相似文献
107.
Shahla Hosseini Bai Fangfang Sun Zhihong Xu Timothy J. Blumfield 《Journal of Soils and Sediments》2013,13(8):1378-1385
Purpose
Understorey Acacia spp. plays an important role in post-fire restoration because these understorey plants are tolerant to stress conditions. We investigated how the ecophysiological status of two species of understorey, Acacia leiocalyx and Acacia disparrima, varied depending on the plant growth stage after prescribed burning.Materials and methods
Plants were grouped in different size classes, namely seedlings, small and medium sizes, and physiological variables such as foliar gas exchange, water use efficiency and light dependency were measured at two experimental sites subjected to prescribed burning.Results and discussion
A. leiocalyx showed higher symbiotic N2 fixation and photosynthetic capacity compared to A. disparrima regardless of plant-size classes at both experimental sites. This could explain the greater relative growth rate of A. leiocalyx than that of A. disparrima. However, A. disparrima is more tolerant to shady conditions than A. leiocalyx.Conclusions
This finding may be an indication of how well these two species recover after fire, although A. leiocalyx may have faster regrowth, as it is fixing more N. 相似文献108.
Effects of treatments with gibberellic acid (GA3, 50 mg L−1 for 2 h) or carbon disulphide (CS2, 25 ml m−3 for four days) on breaking of dormancy and sprouting of potato (Solanum tuberosum L., cvs Agria and Marfona) minitubers of different weight classes (0.3, 0.7 and 1.5 g) were investigated. The dormancy period tended to decrease with an increase in the weight of minitubers, whereas the number of sprouts per minituber, their length and fresh weight and the sprout mass per unit of sprout length of the longest sprout tended to increase with an increase in minituber weight. In both cultivars, applying GA3 or CS2 advanced breaking of dormancy, but GA3 was less effective in Marfona than in Agria. Advancing breaking of dormancy was associated with removal of apical dominance and therefore applying GA3 or CS2 also increased the number of sprouts per minituber, especially in Agria. In Agria, the dry matter content of sprouts from the CS2 treatment was higher than in the GA3 or control treatments, whereas in Marfona dry matter content of sprouts was highest in the GA3 treatment. The length of sprouts, fresh weight of sprouts and the sprout mass per unit of sprout length of the longest sprout were significantly enhanced by treating minitubers with GA3 or CS2 compared with the untreated control minitubers, but there were strong interactions with cultivar and minituber weight. These interactions are important in practical use of dormancy breaking methods. 相似文献
109.
Land-use changes and land cover strongly influence carbon stock and distribution within ecosystems. Changing the land-use from natural forest to other land-uses has been more rapid in the past few decades than at any time in Iran’s history. In this study, we investigated the effects of changing the land-use from natural forest to other land-uses on carbon stocks in northern Iran. We selected five sites for this study: (I) a natural forest, (II) an agricultural field and (III) plantations of three different species (Alnus subcordata. L, Acer velutinum.Boiss and Cupressus sempervirens). We examined the effects of land-use changes on: (I) soil carbon stock (0–50 cm depth), (II) biomass and carbon content of grassy vegetation and litter and (III) above- and below-ground biomass C in trees. Soil C stock was higher under A. velutinum and C. sempervirens whereas it was lower under A. subcordata and agricultural sites. Biomass and C content of grassy vegetation were significantly higher at A. velutinum and C. sempervirens plantations. However, litter biomass and C content were significantly higher at the natural forest site. Natural forest had the highest amount of C content in above- and below-ground biomass. Total ecosystem C stocks declined following land-use changes. 相似文献
110.
Hamid AHANI Hamid JALILVAND Seyed Mohammad HOSSEINI NASR Hossein SOLTANI KOUHBANANI Mohammad Reza GHAZI Hassan MOHAMMADZADEH 《中国林学(英文版)》2013,15(3):231-237
Juniperus species （juniper） are resistant to drought and have medicinal properties. In order to investigatethe condition of juniper reproduction and prevent a decline in its area, largely caused by problems in natural regeneration, the asexual reproduction of juniper has received special attention besides its sexual propagation. Among the six species of juniper in Iran, the most abundant are Juniperus polycarpos and J. excelsa. Juniperus polycarpos is ambi-sexual and J. excelsa unisexual. We show that collecting seeds in September provided for better germination than in November. In sexual propagation 82.0% and in asexual （graft） 47.6% success were achieved. Compared to a mixture of water, lime and hormones, a natural treatment of only water had better results. Diurnal change of temperature increased germination of juniper seeds over a constant temperature. Aphyllous stem cuttings from mature and old trees are less successful in rooting than leafy cuttings of juniper saplings. A treatment with Aaterra significantly reduced the percentage of rooted cuttings and total root length. Aliette, Fongarid, Octave, Benomyl, Delsene M and Maneb fungicides significantly increased the percentage of rooted cuttings but did not affect total root length. Autumn explants formed more calli than spring explants. Successful multiplication was achieved by treating buds with a mixture of 0.7% polyvinyl pyrrolidone （PVP） and 2% sucrose and cultured in a basal MS or WRC medium, with a maximum number of new buds. In consideration of extracted material of juniper species in remedy of infectious, fungus, contagious diseases as well as for drought resistance and longevity of this species in severe arid environmental conditions and various industrial applications, reproduction and seed production by micro propagation and biotechnology are necessary. 相似文献