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11.
Saeid Amiri Mohammad Jafari Jozani Reza Modarres 《Journal of Agricultural, Biological & Environmental Statistics》2014,19(1):1-17
Ranked set sampling is a sampling approach that could lead to improved statistical inference when the actual measurement of the variable of interest is difficult or expensive to obtain but sampling units can be easily ordered by some means without actual quantification. In this paper, we consider the problem of bootstrapping an unbalanced ranked set sample (URSS) where the number of observations from each artificially created stratum can be unequal. We discuss resampling a URSS through transforming it into a balanced RSS and extending the existing algorithms. We propose two methods that are designed to obtain resamples from the given URSS. Algorithms are provided and several properties, including asymptotic normality of estimates, are discussed. The proposed methods are compared with the parametric bootstrap using Monte Carlo simulations for the problem of testing a hypothesis about the population mean. 相似文献
12.
Hadi Jafari Mohammad Zare Ali Akbar Kamgar Haghighi 《Archives of Agronomy and Soil Science》2013,59(6):673-689
The irrigation return-flow coefficient (IRFC) is based on rule of thumb estimations in most aquifers in Iran. The errors may be significant, and thus misleading for water resources management. We used lysimeters to more accurately predict IRFC. Five wheat and barley farms of different soil textures, which were irrigated using a border system, plus one with a sprinkler system, were selected for the installation of lysimeters. The practices at each farm were applied to the lysimeters. Irrigation return flows (IRF) were measured every other day over two growing seasons. The IRF time series displayed sharp peaks at the initial stages of the growing season and decreasing towards the end. IRFCs were classified into early and late stages. The average IRFC during the early stage was 29.9%, decreasing to 6.5% in the late stage. High IRFC values are due to the limitations of border irrigation to provide a small uniform amount of water, and over-irrigation due to low water demand during the early stage of growth. Variations in annual IRFCs of 0.4 to 38.7% are functions of total applied water, border length, management and soil texture. The early stage IRFC for the sprinkler system was small. Therefore, high early stage IRFCs can be reduced by changing from border irrigation to a sprinkler system. 相似文献
13.
Sadighi A Elmi A Jafari MA Sadeghifard V Goldust M 《Pakistan journal of biological sciences: PJBS》2011,14(20):950-953
Tibia fractures are the most common type of long bone fractures in US. This study aimed at comparing the therapeutic results of closed tibial shaft fracture with intramedullary nails inserted with and without reaming. In this randomized clinical trial study, 60 patients with a fracture of the tibia were examined. The patients were randomly divided into two groups. Thirty patients treated through inserting intramedullary nail with reaming technique (group A). The other 30 patients treated through inserting intramedullary nail without reaming technique (group B). After operation physical examination and control radiography were taken up to 6 month and results were compared. Sixty patients suffering from closed tibial diaphysis fractures were studied. Mean age of the group A and B were 40.24 +/- 12.32 and 38.42 +/- 14.28, respectively. Group A consisted of 24 (80%) males and 6 (20%) females while group B consisted of 24% females and 76% males. Considering fracture based on OTA criteria (p = 0.4) and severity of soft tissue damage based on Tscherne classification (p = 0.6), there was no statistically meaningful difference between groups A and B. The study demonstrated that degree of horizontal displacement, mean time of surgery, post-operation infection, organ shortness at the end of the follow-up period, organ deviation in patients of the group A was significantly more than that of the group B. Time required for callus formation (mean time of union), mean time of full weight bearing time and mean time of return to normal activities in group B was significantly more than that of the group A. 相似文献
14.
Elham Karimzadeh Jafari Hamed Naghavi Hooman Latifi 《Journal of Sustainable Forestry》2020,39(7):750-770
ABSTRACT Background: Traditional field-based methods of measurement of biomass and carbon storage face difficulty in collecting time-consuming and expensive, suggests the use of remote sensing-based techniques. It estimates the economic value of the aboveground biomass (AGB) using satellite remote sensing across the Hyrcanian forests of Iran. Methods: The Landsat-8 OLI sensor data were combined with field-based allometric information of 186 circular sample plots. The AGB was calculated at the plot level using the collected data and specific volumetric mass for species in the studied area. It was followed by calculating the carbon storage using a 50% carbon coefficient and the photosynthesis equation at the forest parcel level. Model results using the random forest and support vector machines. The carbon sequestration value was calculated with USD 25.3 as a shadow value of carbon in 2014 and using the replacement cost approach. Results: The highest performances achieved by RF for biomass, carbon storage and the carbon storage value (Iranian Rials of 0.67% and 16%, respectively). The value was derived once at the plot level of 12.22 million IRR (370.43 USD) per ha. In addition, at the parcel level, which resulted in an estimated value of 12.87 million IRR (390.24 USD) per ha. 相似文献
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16.
Farzaneh Noori Naser Agh Fatemeh Jafari Reza Jalili Enric Gisbert Mansour Torfi Mozanzadeh 《Aquaculture Nutrition》2019,25(5):1050-1062
The influence of dietary fish oil (FO) substitution with blends of vegetal oils (VO: canola, linseed, olive, sunflower, corn and coconut oils) in plant protein‐rich diets on reproductive performance and fatty acid dynamics of embryos was evaluated in female rainbow trout (Oncorhynchus mykiss) brooders (1.8 ± 0.1 kg). Four diets were formulated in which 20% (FO80/VO20), 50% (FO50/VO50), 75% (FO25/VO75) and 100% (VO100) of FO were replaced by mixture of VO. The above‐mentioned diets were administered for a short period prior to spawning (3 months). Fish fed the VO100 had the lowest fertilization rate (81.3 ± 2.3), whereas brooders fed the FO80/VO20 diet had the lowest survival rates at eyed embryo stage (83.7 ± 1.6%) and hatching rate (79.9 ± 3.1%). The fatty acid dynamics of embryos were not only affected by embryonic developmental stages, but also they were influenced by the dietary fatty acid profile. Our study confirmed that using blends of different VO sources and FM residual fat in the FO25/VO75 for the short‐term period prior to spawning seemed to be a good strategy in terms of successful reproduction for sparing high levels of FM and FO in diet of O. mykiss brooders. 相似文献
17.
Naser Agh Mansour Torfi Mozanzadeh Fatemeh Jafari Farzaneh Noori Reza Jalili 《Aquaculture Research》2020,51(3):918-931
A 90‐day feeding trial was carried out to examine the influence of fish oil (FO) substitution with blends of vegetable oils (VOs) on reproductive efficiency of female brooders and fluctuation in fatty acid (FA) profile of embryos in Oncorhynchus mykiss. A basal diet was formulated in which 20% (80FO/20VO), 50% (50FO/50VO), 75% (25FO/75VO) and 100% (100VO) of FO were replaced by mixture of VO. Reproductive performance of brooders was not affected by drastic alternations in FA profile of diets. The level of saturated and monounsaturated FAs (MUFAs) significantly increased, whereas the levels of long‐chain polyunsaturated FAs (LC‐PUFAs), mainly docosahexaenoic acid, profoundly decreased during embryogenesis. The concentrations of MUFA and n?6 PUFA increased in the eggs with increasing the incorporation of VO mixture in diets; however, the concentration of LC‐PUFA and n?3/n?6 PUFA ratio decreased. Haematological parameters and humoral immune responses including total immunoglobulin content, lysozyme and alternative complement pathway activities in brooders fed with the experimental diets did not statically different. In summary, incorporating mixture of various VO sources especially linseed and sunflower oils as good sources of α‐linolenic and linoleic acids, respectively, along with low levels of residual fat from fish meal in diet suggested a good strategy for providing the appropriate essential FA requirements of O. mykiss brooders for their successful reproduction. 相似文献
18.
Mohammad Hossein Boskabady Mahbobaeh Ghasemzadeh RahbardarZahra Jafari 《Fitoterapia》2011,82(2):162-167
The effect of three concentrations of safranal on histamine (H1) receptors was tested on two groups of tracheal chains incubated with: 1) indomethacin, and 2) indomethacin, propranolol and atropine (n = 6). The EC50 (effective concentration of histamine causing 50% of maximum response) obtained in the presence of chlorpheniramine and all concentrations of safranal in both groups were significantly greater than those of saline (p < 0.05 to p < 0.001). The EC50 obtained in the presence of all concentrations of safranal and maximum response of its two higher concentrations (1.25 and 2.5 μg/mL) in group 2 were greater than in group 1 (p < 0.05 to p < 0.001). 相似文献
19.
The efficacy of ivermectin was evaluated against Melophagus ovinus in Darab ecotype goats of Iran. Twenty-four healthy Iranian crossbreed male goats were randomly divided into three equal groups (n = 8). An experimental infestation was induced in all animals of the three groups with 100 M. ovinus on the body of each animal. Groups 1 and 2 were treated with 1% ivermectin solution at a dosage of 0.5 mg/kg of body weight applied as a pour-on along the dorsal midline and 0.2 mg/kg subcutaneously, respectively; while group 3 was kept as control group. Seven days after infestation ivermectin was administered then the goats were observed for a period of 7 days. Body surface of each goat of three groups was inspected daily and decreases in M. ovinus were recorded. The rate of elimination in keds was assessed on the basis of decrease in keds count on the skin and hairs. The results revealed that complete absence of keds were observed in 6 and 7 days post-treatment with injection and pour-on routes, respectively. The results of present study showed that subcutaneous injection of ivermectin more rapidly eliminated M. ovinus than pour-on route. Both routes were 100% effective against this parasite in the goats. Ivermectin can be a drug of choice against M. ovinus in long-hair Iranian goats due to its high efficacy, easy applicability and wide safety margin. 相似文献
20.
Nasibeh Jafari Loghman Karimi Mohammad Mirjalili Seyed Javad Derakhshan 《Fibers and Polymers》2016,17(6):888-895
In this study silver nanoparticles with different particle sizes and hence colors were synthesized on silk and cotton fabrics through reduction of silver nitrate. Particle sizes of the silver colloids were measured by dynamic light scattering (DLS). The structure and properties of the treated fabrics were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and UV-Vis reflectance spectroscopy. Various characteristics of the treated fabrics including antibacterial activities against a Gram positive (Staphylococcus aureus) and a Gram negative (Escherichia coli) bacteria, color effect, wash and light fastness, water absorption, fabric rigidity, and UV blocking properties were also assessed. The results indicated that the treated fabrics displayed different colors in the presence of silver nanoparticles with different particle sizes and exhibited good and durable fastness properties. Also, the size of the silver particles had a tangible effect on antibacterial activity of treated fabrics and its antibacterial performance was improved by decreasing the size of particles. Moreover, this process imparted significantly UV blocking activity to fabric samples. 相似文献