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51.
A survey was carried out to investigate the prevalence of hard tick species (Acari: Ixodidae) on cattle and sheep southeast of Iran. A total of 972 ticks were collected from 280 infested cattle and 1,207 ticks were collected from 632 infested sheep during activating seasons of ticks in 2008–2009. The species collected from cattle were Hyalomma marginatum marginatum (50.92%), Hyalomma anatolicum excavatum (25.61%), Hyalomma anatolicum anatolicum (8.12%), Hyalomma asiaticum asiaticum (1.85%), and Rhipicephalus sanguineus (13.47%) while the species collected from sheep were R. sanguineus (36.37%), H. marginatum marginatum (30.65%), H. anatolicum excavatum (19.05%), H. asiaticum asiaticum (10.52%), Hyalomma detritum (3.14%), and Dermacentor marginatus (0.24%). The results show that, H. marginatum marginatum, H. anatolicum excavatum, and R. sanguineus are dominant tick species in the surveyed area.  相似文献   
52.
Salicylic acid (SA) occurs naturally in plants at low concentrations. Previous studies reported a vast range of responses after SA application on plants. Nickel (Ni) as an essential element for plant growth and development has been proven to have positive impact on overall plant life cycle. To evaluate influence of these two compounds on strawberry plants cv. ‘Pajero’ this study was carried out as a 3 × 4 factorial in a completely randomized design in greenhouse conditions. Treatments included SA at 0, 1, 2, and 3 mM and nickel sulfate (NiSO4) at 0, 150 and 300 mg L?1 concentration. It seems that treatments had promoting effects on measured parameters as 2 mM of SA increased root and shoot fresh and dry weight, concentration of anthocyanins and poliphenolics of fruits significantly, 3 mM of this phytohormone caused augmentation of vitamin C content of fruits. Nitrogen and nickel concentration within leaves and fruits were affected after SA treatments. 150 mg L?1 of nickel solution promoted total yield, root dry weight and nitrogen concentration of fruits. Worth mentioning, beneficial effects of such treatments were higher when applied together. Further research is needed before recommendation on other cultivars and commercial use.  相似文献   
53.
Foliar application of fertilizers can guarantee the availability of nutrients to rice for obtaining higher yield. Rice responds favorably to macro- and micronutrients and the tolerance to salinity hazards improves by decreasing the N/S ratio. In this study, results showed that nutrient concentrations (g L?1) for rice are: nitrogen (N) 108.0, phosphorous (P2O5) 6, potassium (K2O) 81.0, calcium (CaO) 15.0, and magnesium (MgO) 6 g L?1; and for iron (Fe), manganese (Mn), zinc (Zn), cupper (Cu), boron (B), molybdenum (Mo) and silicon (Si) the recommended concentrations are 0.6, 0.45, 0.21, 0.06, 0.09, 0.0002 and 0.004 g L?1, respectively. A significant increase was recorded in number of panicles m?2, 1000 grain weight, biological yield and grain yield with foliar application of nutrients. Five foliar applications of nutrients resulted in maximum number of panicles m?2, grains panicle?1, 1000 grain weight and biological yield. It is concluded that five foliar applications of balanced amounts of fertilizers at the seedling stage (two sprays), tillering (single spray) and at panicle initiation and panicle differentiation (two sprays) helped in enhancing yield and yield components of rice. In this research, five foliar applications produced the smallest damaging effects of blast (Pyricularia oryzae) in rice.  相似文献   
54.
The aim of this study was to compare, levels of genetic polymorphism between Iranian and Azeri bream (Abramis brama orientalis) populations using five microsatellite loci. The reduced number of alleles in the Iranian populations compared with the Azeri population led us to infer that the genetic variability of the Iranian stocks has been reduced due to inbreeding and genetic drift. Significant population differentiation (Fst) was observed between the Azeri and the Iranian populations, which could be explained by the higher number of alleles in the Azeri population. Significant deviations from Hardy–Weinberg equilibrium were found at more loci in the Iranian populations than the Azeri population. Beyond the hypothesis of null alleles, the heterozygote deficiency may have arisen due to breeding between related individuals in the Iranian populations. This investigation represents the first approach to the knowledge of the genetic variability of Iranian and Azeri bream populations using microsatellite markers, and the reported results could be of interest for management and conservation programmes of this species in Iran.  相似文献   
55.

Background:

β-thalassemia is the most common monogenic disorder in human. The (CT) polymorphism at -158 upstream region of the γG-globin gene and pharmacological factors such as hydroxyurea have been reported to influence γ-globin gene expression and the severity of clinical symptoms of β-thalassemia.

Methods:

In the present study, 51 β-thalassemia intermediate patients were studied. Xmn1γG polymorphism genotype was determined using Tetra-Primer ARMS-PCR technique. Hemoglobin (Hb) and fetal hemoglobin (HbF) levels were determined by gel electrophoresis.

Results:

Of 51 patients, 35 (68.6%) patients were heterozygous (CT) and 16 (31.4%) patients were homozygous (CC). Of 30 patients under treatment by hydroxyurea, 20 (66.7%) patients were heterozygous (CT) and 10 (33.3%) patients were homozygous (CC). Our results demonstrated that in the heterozygous (CT) genotype, the Hb (9.58 ± 1.25 gm/dl) and HbF (89.30 ± 21.87) levels were significantly higher in comparison with homozygous (CC) genotype (7.94 ± 1.34 gm/dl and 70.32 ± 40.56, respectively). Furthermore, we observed that after drug usage, the Hb and HbF levels in patients with heterozygous (CT) genotype (0.7 ± 1.26 gm/dl and 5.95±14.8, respectively) raised more in comparison with homozygous (CC) genotype (0.26 ± 1.43 gm/dl and 0.8 ± 1.31, respectively).

Conclusion:

Hb and HbF levels in the patients carrying T allele are increased significantly, and they also response to hydroxyurea treatment.Key Words: Fetal hemoglobin (HbF), Hydroxyurea, Intermediate β-thalassemia  相似文献   
56.
In this study, a temperature sensitive shape memory polymer (SMP) system based on polylactic acid (PLA) has been developed and the effect of graphene nanoplatelets (GNPs) on the shape memory properties was evaluated. Dispersion of GNPs in PLA was improved with the aid of a zwitterionic surfactant. X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed that the surface modified graphene nanoplatelets (SMGNPs) were exfoliated and homogenously dispersed in the PLA matrix due to enhancement of the polymer-graphene interaction. Mechanical properties of the samples namely stiffness and elasticity were increased upon incorporation of graphene nanoplatelets accompanied by their good dispersion in the PLA matrix. Furthermore, differential scanning calorimetry (DSC) revealed that the nucleation effect of graphene promote the crystallization and noticeably enhanced the degree of crystallinity. Finally, prominent mechanical properties along with high degree of crystallization due to fine dispersion of surface modified graphenes, resulted in drastic improvement in shape memory performance.  相似文献   
57.
Long-term effects of different levels of dietary vermicompost manure leachate powder (VCL) were investigated on the nauplii growth and survival, biochemical composition, total carotenoids, and reproductive performance of broodstock Artemia franciscana in laboratory cultures. The instar I nauplii were fed in five treatments including 100% of the microalga Dunaliella salina (Alg; control group, with a density of 18?×?106 cells mL?1) and mixtures of 75% Alg-25% VCL, 50% Alg-50% VCL, 25% Alg-75% VCL, and 100% VCL for 3 weeks. At maturity, 35 pairs (males and females) were individually isolated from each treatment and transferred to 50-mL falcon tubes in which the reproduction and longevity of females were monitored until mortality. Results showed that the total length of Artemia in the control, 75 Alg-25 VCL, and 50 Alg-50 VCL treatments was significantly different from the other groups at the end of the 2nd and 3rd weeks. The pre-puberty survival rate was severely affected by the increased dietary levels of VCL declining from 52% (control) to 6.7% (100 VCL). The adults’ body protein levels in the control and 75 Alg-25 VCL (54–57%) were similar, but both groups were significantly different from the other treatments. However, the lipid content (13.7–19.8%) and total carotenoids (36.5–47.7 μg mg?1) were significantly different between treatments. Many broodstocks’ reproductive characteristics were affected by the diet so that the total number of offspring in the control was markedly higher than the other groups. However, the number of offspring per brood revealed no differences between the control and 75 Alg-25 VCL treatment, but both were significantly dissimilar with the other groups. The interval between two successive brood productions detected in 100 VCL was almost double those in the other groups. The lifetimes of Artemia were not significantly different in the treatments received varied algal diets with the lowest lifespan in 100 VCL treatment. By increasing VCL to over 25%, the growth, survival, and particularly females’ reproductive performance decreased significantly so that Artemia had to be fed only up to 25% VCL (with 75% Alg). These findings indicate an inefficiency of VCL powder supply in long-term feeding to A. franciscana. Moreover, the use of only 25% VCL is apparently appropriate in small-scale laboratory cultures.  相似文献   
58.
This study was performed to investigate the effect of dietary supplementation with Aloe vera (AV) powder and synbiotic as growth promoter agents on performance, gut morphology, immune responses, hematology and serum biochemistry in broilers. A total of 240‐day‐old male broiler chicks (Ross 308) were randomly assigned to six treatments with four replicates. Birds were offered either a corn‐soybean meal basal diet (control) or the basal diet supplemented with 200 mg/kg virginiamycin (VM), 1 g/kg synbiotic (Syn), 2.5 g/kg AV (AV1), 5.0 g/kg AV (AV2) or 7.5 g/kg AV (AV3). Chickens fed any of the diets, except diet AV1, exhibited better feed conversion ratios at the 14–28 day period and higher average daily gain and duodenal villus height/crypt depth ratio at 42 days than those fed the control diet. Synbiotic supplementation caused a marked increase in the serum antibody titer against infectious bursal disease and infectious bronchitis vaccines. Feeding diet AV3 significantly increased red blood cell count and hemoglobin concentration, and decreased serum triglyceride level compared to the control group. The results suggested that dietary inclusion of 5 and 7.5 g/kg AV, similar with synbiotic supplementation, can be applied as effective alternatives to in‐feed antibiotics for broiler diets.  相似文献   
59.
Among physical characteristics, dimensions, mass, volume and projected areas are important parameters in sizing and grading systems. Fruits with the similar weight and uniform shape are desirable in terms of marketing value. Therefore, grading fruit based on weight reduces packing and handling costs and also provides suitable packing patterns. The different grading systems require different fruit sizing based on particular parameters. In this study pomegranate mass was predicted by applying different physical characteristics with linear and nonlinear models as three different classifications: (1) single or multiple variable regressions of pomegranate dimensional characteristics, (2) single or multiple variable regression of pomegranate projected areas and (3) estimating pomegranate mass based on its volume. The results showed that mass modeling of pomegranate based on minor diameter and three projected areas are the most appropriate models in the first and second classifications, respectively. In third classification, the highest determination coefficient was obtained for mass modeling based on the actual volume as R2 = 0.99 whereas corresponding values were 0.93 and 0.79 for assumed pomegranate shapes (oblate spheroid and ellipsoid), respectively. In economical and agronomical point of view, suitable grading system of pomegranate mass was ascertained based on minor diameter as nonlinear relation M = 0.06c2 − 4.11c + 143.56, R2 = 0.91.  相似文献   
60.
New bio‐based dietary supplement with micronutrients for livestock was elaborated. The new preparation was tested on laying hens to determine the influence of new biological feed additives on the level of trace elements in egg content. The diet of laying hens (Hy‐Line Brown, 30 weeks of age) was supplemented with soya bean meal enriched with Cu(II), Zn(II), Fe(II) and Cr(III) by biosorption. A total of 150 laying hens were divided into five groups: one control and four experimental. In the control group, microelements were supplemented in the inorganic form, whereas in experimental groups, Cu, Zn, Fe and Cr were replaced with soya bean meal enriched with a given microelement ion. The feeding experiment was conducted for 12 weeks and was divided into three series. The results showed that adding the new feed additives to the diet of laying hens had an impact on microelement transfer to eggs, in particular with increased dosing. Eggs were biofortified with iron, zinc and copper and to a lesser extent with chromium. The microelements were accumulated primarily in the albumen because soy protein was the carrier of micronutrient ions in hens’ diet. Transfer of trace elements to eggs was not linearly dependent on the dosage of biologically bound microelements in the diet.  相似文献   
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