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101.
Rohollah Ghasemi Mehran Torki Hossein Ali Ghasemi 《Tropical animal health and production》2014,46(5):717-723
The objective of this study was to determine the effects of different levels of crude protein (CP) and dietary electrolyte balance (DEB) on productive performance, egg quality, and blood biochemical parameters of laying hens reared during hot summer months. The average minimum and maximum room temperatures recorded from 32 to 42 weeks of age were 27.2 and 36.5 °C, respectively, with relative humidity ranging from 48 to 56 %. A total of 144 Lohmann LSL-Lite laying hens were assigned to each of four dietary treatments with six replicate cages of six birds. The treatments were as follows: CP 15.4 % + DEB 165 mEq/kg (group 1), CP 15.4 % + DEB 250 mEq/kg (group 2), CP 13.9 % + DEB 165 mEq/kg (group 3), and CP 13.9 % + DEB 250 mEq/kg (group 4). In groups 3 and 4, feed conversion ratio and blood uric acid were decreased (P?<?0.05); but the plasma triglyceride level was increased (P?<?0.05) compared to groups 1 and 2. Low-CP diet with DEB 250 (group 4) also induced significant increases of average egg production and eggshell thickness compared to group 1. Blood pH, Na+, and HCO3 ? values were also higher (P?<?0.05) in groups 2 and 4 than in the other groups. These results indicate that, under tropical conditions, using a DEB of 250 mEq/kg achieves a correction of the lay-induced metabolic acidosis and induces a positive effect on eggshell quality when the hens were fed low-protein diet. 相似文献
102.
103.
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
104.
Hossein Madadi Emad Mohajeri Parizi Hossein Allahyari Annie Enkegaard 《Journal of pest science》2011,84(4):447-455
Lady beetles are among the most successful predators of aphids in different environments. The functional responses of different
life stages of Hippodamia variegata (Goeze) towards cotton aphids were examined in two different set-ups, a two-dimensional Petri dish set-up with detached leaves
and a three-dimensional set-up with whole plants. In addition, the functional responses in two-dimensional set-ups towards
cotton aphids and the pea aphids were compared. H. variegata exhibited a functional type II response to both cotton aphids and pea aphids irrespective of life stage and spatial scale
of the set-up. Females and fourth instars generally had higher search rates than third instars whereas handling times were
consistently lower for the fourth instar stage compared with the preceding juvenile stage and with females. The spatial dimensions
did not have any significant influence on the functional responses towards cotton aphids, except for third instars which in
the three-dimensional set-up reduced their search rate and increased their handling time. Fourth instars reacted in the same
way to both Aphis gossypii and Acyrthosiphon pisum whereas the functional response parameters for third instars and females were significantly different on the two prey species.
Our study, a part of this first-step evaluation of H. variegata as a biocontrol agent against A. gossypii and A. pisum under field condition, suggest that the voracity of all tested stages of H. variegata towards both aphid species hold good promises for a use of especially fourth instars and females in inundative biocontrol. 相似文献
105.
Hassanpour H Momtaz H Shahgholian L Bagheri R Sarfaraz S Heydaripoor B 《Research in veterinary science》2011,91(3):370-375
To investigate the effect of T3-induced pulmonary hypertension on endothelin (ET) production and genes expression of ET-1, ETA and ETB receptors (ETAR and ETBR) during rearing, semiquantitative RT-PCR and enzyme immunometric assay were performed in the heart ventricles and serum, respectively. The ET-1 and its receptor genes were expressed in the right and left ventricles of control and T3-treated broilers at 12, 28 and 49 days of age. There were significant (P < 0.05) reductions of the relative amounts of ET-1 (in both ventricles) and ETAR (in the right ventricle) mRNAs at 28 and 49 days of age, in T3-treated broilers compared to controls. The relative amounts of ETBR mRNA in the right and left ventricles did not significantly differ between control and T3-treated broilers at any age. The serum level of ET was significantly (P < 0.05) increased in T3-treated chickens at 28 and 49 days of age when compared with that of the control. It is concluded that ET-1, ETAR and ETBR genes are normally expressed in the heart ventricles of broilers. It is likely that increased serum level of ET and decreased ET-1/ETAR genes expression in the ventricles are involved in the heart dysfunction of broiler chickens with developmental pulmonary hypertension. 相似文献
106.
Gerardo Lopez Christian Larrigaudière Joan Girona M. Hossein Behboudian Jordi Marsal 《Scientia Horticulturae》2011
Fruit thinning in pear is feasible for mitigation of water stress effects. However, it is not well known how fruit quality at harvest and after cold storage is affected by pre-harvest water stress. Even less is known about the effects of fruit thinning on quality under these circumstances. To elucidate these, we applied deficit irrigation (DI) and fruit thinning treatments to ‘Conference’ pear over the growing seasons of 2008 and 2009. At the onset of Stage II (80 and 67 days before harvest in 2008 and 2009, respectively), two irrigation treatments were applied: full irrigation (FI) and DI. FI trees received 100% of crop evapotranspiration (ETc). DI trees received no irrigation during the first three weeks of Stage II to induce water stress, but then received 20% of ETc to ensure tree survival. From bud-break until the onset of Stage II and during post-harvest, FI and DI trees received 100% of ETc. Each irrigation treatment received two thinning levels: no thinning leaving commercial crop load (∼180 fruits tree−1), and hand-thinning at the onset of Stage II leaving a light crop load (∼85 fruits tree−1). Under commercial crop loads, DI trees were moderately water-stressed and this had some positive effects on fruit quality. DI increased fruit firmness (FF), soluble solids concentrations (SSC) and acidity at harvest while no changes were observed in fruit maturity (based on ethylene production). Differences in FF and acidity at harvest between FI and DI fruit were maintained during cold storage. DI also reduced fruit weight loss during storage. But fruit size was reduced under DI. Fruit thinning under DI resulted in better fruit composition with no detrimental effect on fresh-market yield compared to un-thinned fruit. Fruit size at harvest and SSC values after five months of cold storage were higher in fruit from thinned trees than fruit from un-thinned trees. Fruit thinning increased fruit ethylene production, indicating advanced maturity. This may lead to earlier harvest which is desirable in years with impending drought. Fruit thinning is therefore a useful technique to enhance pear marketability under water shortage. 相似文献
107.
Hossein Ebrahimnezhad-Khaljiri Reza Eslami-Farsani Kousha Abbas Banaie 《Fibers and Polymers》2017,18(2):296-302
In this research work, aramid and semi-carbon fibers (SCFs) were hybridized in the form of interlayer or layer by layer into epoxy matrix by hand lay-up method. Afterward, the effect of hybridization on the thermal and mechanical properties of epoxy composites was characterized by thermal analysis; horizontal burning; tensile and bending tests. Based on the results of the mechanical tests, increasing SCFs to aramid fibers ratio decreased tensile strength, elastic and flexural modulus. But with increasing this ratio to 53 % failure strain reduced, whereas in the ratios of more than 53 %, the failure strain enhanced. The results of thermal analysis curves indicated that there are three stage mass loss at the temperature ranges of 100-220, 270-470 and 500-620 °C. It was also found that with increasing the SCFs to aramid fibers ratio decreased the third-stage of the mass loss. The results of horizontal burning showed that increasing the SCFs to aramid fibers ratio decreased the rate of burning. 相似文献
108.
Abouzar Hatam Kambiz Pourtahmasi Hossein Resalati A. Hossein Lohrasebi 《Wood Science and Technology》2008,42(5):353-367
Due to the variations in opacity and brightness of peroxide bleached pulp at Mazandaran Wood and Paper Industries Company
(MWPI), empirical models were developed to predict chemimechanical pulp (CMP) brightness and opacity from peroxide bleaching
conditions and to drive the optimum operating conditions. To overcome the inconsistency problem, a multi-variate regression
analysis method was used for model building. The models were then validated using a new data set from the bleach plant at
MWPI, assessing the models’ predictive ability and performance. The results show that there is a relationship between bleaching
variables and such dependent variables as pulp brightness and opacity. In addition to the hydrogen peroxide charge and pulp
initial brightness, the initial opacity had a significant reverse effect on the final CMP brightness. It was also found that
the concentration of total Na+ in the CMP tower was the most important variable affecting the final pulp opacity. The validation results demonstrated that
these models can be employed as useful tools for process optimization purposes. 相似文献
109.
In this paper, a softener of aliphatic acid ester was treated with an ultrasonic bath and coated on cotton. The particle size distribution of the softener in water was evaluated by a particle size analyzer. Physical and surface properties of the fabric after coating with the ultrasonic treated softener were compared with a control sample. Different technical measurements were utilized for this purpose including bending lengths measurement (BLM), friction coefficient measurement (FCM), evaluation of crease recovery angle (CRA), moisture regain measurement (MRM), evaluation of contact angle (CA), reflectance spectroscopy (RS), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Results showed that ultrasound enhances softener distribution in water and it improves the drapeability, friction behavior, wrinkle recovery and water repellency of cotton due to uniform coating of softener. 相似文献
110.
Sevda Amini Hossein Ghadiri Chengrong Chen Petra Marschner 《Journal of Soils and Sediments》2016,16(3):939-953