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61.
Contrasting soil microbial responses to fertilization and tillage systems in canola rhizosphere 总被引:1,自引:0,他引:1
Khosro Mohammadi Gholamreza Heidari Mohammad Tahsin Karimi Nezhad Salah Ghamari Yousef Sohrabi 《Saudi Journal of Biological Sciences》2012,19(3):377-383
Information regarding the simultaneous evaluation of tillage and fertilization on the soil biological traits in canola production is not available. Therefore, field experiments were conducted in 2007–2010 in a split plot based on randomized complete block design with three replications. Main plots consisted of conventional tillage (CT); minimum tillage (MT) and no tillage (NT). Six strategies of fertilization including (N1): farmyard manure (cattle manure); (N2): compost; (N3): chemical fertilizers; (N4): farmyard manure + compost; (N5): farmyard manure + compost + chemical fertilizers and (N6): control, were arranged in sub plots. Results showed that the addition of organic manure increased the soil microbial biomass. No tillage system increased microbial biomass compared to other tillage systems. The activities of all enzymes were generally higher in the N4 treatment. The activity of phosphatase and urease tended to be higher in the no tillage treatment compared to the CT and MT treatments. 相似文献
62.
We introduce a modified-firing-rate model based on Hebbian-type changing synaptic connections. The existence and stability
of solutions such as rest state, bumps, and traveling waves are shown for this type of model. Three types of kernels, namely
exponential, Mexican hat, and periodic synaptic connections, are considered. In the former two cases, the existence of a rest
state solution is proved and the conditions for their stability are found. Bump solutions are shown for two kinds of synaptic
kernels, and their stability is investigated by constructing a corresponding Evans function that holds for a specific range
of values of the kernel coefficient strength (KCS). Applying a similar method, we consider exponential synaptic connections,
where traveling wave solutions are shown to exist. Simulation and numerical analysis are presented for all these cases to
illustrate the resulting solutions and their stability. 相似文献
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Fardin Asadi Mehran Mohseni Karim Dadashi Noshahr Fariba Haj Soleymani Ahmad Jalilvand Azam Heidari 《Biological trace element research》2017,175(1):50-56
Despite an increasing surge in application of nanoparticles in industries, there is a serious lack of information concerning their impact on human health and the environment. The present study investigated effects of molybdenum nanoparticles (Mo NPs) injected intraperitoneally into Sprague-Dawley rats at different doses of Mo NPs (5, 10, and 15 mg/kg BW per day) during a period of 28 days. Hematological and biochemical parameters as well as sexual hormones and histopathological examinations of the liver and testis were assessed and compared with control group. The results showed that the serum levels of testosterone decreased significantly in both groups of 10 and 15 mg (Mo NPs)/kg BW in comparison with the control group (p < 0.05). However, there were insignificant differences observed in luteinizing hormone (LH) levels and hematological parameters when compared with the control group (p > 0.05). The results of liver enzymes showed that serum levels of aspartate aminotransferase (AST) decreased significantly in both dosage groups of 5 and 10 mg/kg BW (Mo NPs) when compared with the control group (p < 0.05), and significant decrease obtained in lactate dehydrogenase (LDH) levels at dose of 5 mg/kg BW in comparison with the control group (p < 0.05). The histopathological examination of testis showed a decrease in number of Leydig cells. Also, the number of chronic inflammatory cells increased in portal triad and parenchyma in liver tissue of rats exposed to Mo NPs. 相似文献
65.
Length–weight and length–length relationships for nine species of the genus Paracobitis (Nemacheiliidae) in Iran
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H. Mousavi‐Sabet A. Heidari S. Vatandoust 《Zeitschrift fur angewandte Ichthyologie》2017,33(3):617-619
Length–weight (LWR) and length–length (LLR) relationships were estimated for 330 specimens from nine Paracobitis species in 11 localities throughout Iran. All fish were collected upon occasion by electrofishing throughout Iran from July 2010 to October 2016. These represent the first reports of LWR data for eight species including: Paracobitis atrakensis, P. hircanica, P. longicauda, P. molavii, P. persa, P. rhadinaeus, P. smithi and P. vignai and first LLR data for all species. A new maximum length is reported for P. malapterura. Four of these species are endemic and five species are native to Iran. The length–weight parameter b ranged from a minimum of 2.74 for P. atrakensis to a maximum of 3.01 for P. longicauda, with regression coefficients (r2) ranging from 0.96 to 0.99. All LLRs were highly significant (r2 > .96). 相似文献
66.
Length–weight relationships of six species of the genera Cobitis and Sabanejewia (Cobitidae) in Iranian river systems
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H. Mousavi‐Sabet A. Heidari K. Abbasi S. Vatandoust 《Zeitschrift fur angewandte Ichthyologie》2016,32(6):1310-1312
Length‐weight relationships (LWRs) were estimated for six spined loach species from Iran. Data were collected between 2010 and 2015. These represent the first reports of length–weight data for five of the species (Cobitis avicennae, Cobitis faridpaki, Cobitis keyvani, Sabanejewia aurata and Sabanejewia caspia) while also providing additional data on the remaining species (Cobitis linea). Five of these species are endemic and the remaining S. caspia, is native to the country. Estimated b values obtained for the studied species ranged from 2.381 for S. aurata to 3.411 for C. keyvani. 相似文献
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Andrew E. Heidari Tiffany T. Pham Ibe Ifegwu Ross Burwell William B. Armstrong Tjoa Tjoson Stephanie Whyte Carmen Giorgioni Beverly Wang Brian J. F. Wong Zhongping Chen 《Journal of biophotonics》2020,13(3)
Incomplete surgical resection of head and neck squamous cell carcinoma (HNSCC) is the most common cause of local HNSCC recurrence. Currently, surgeons rely on preoperative imaging, direct visualization, palpation and frozen section to determine the extent of tissue resection. It has been demonstrated that optical coherence tomography (OCT), a minimally invasive, nonionizing near infrared mesoscopic imaging modality can resolve subsurface differences between normal and abnormal head and neck mucosa. Previous work has utilized two‐dimensional OCT imaging which is limited to the evaluation of small regions of interest generated frame by frame. OCT technology is capable of performing rapid volumetric imaging, but the capacity and expertise to analyze this massive amount of image data is lacking. In this study, we evaluate the ability of a retrained convolutional neural network to classify three‐dimensional OCT images of head and neck mucosa to differentiate normal and abnormal tissues with sensitivity and specificity of 100% and 70%, respectively. This method has the potential to serve as a real‐time analytic tool in the assessment of surgical margins. 相似文献
70.
Transmission blocking vaccines (TBVs) that target the antigens on the midgut epithelium of Anopheles mosquitoes are among the promising tools for the elimination of the malaria parasite. Characterization and analysis of effective antigens is the first step to design TBVs. Calreticulin (CRT), a lectin-like protein, from Anopheles albimanus midgut, has shown antigenic features, suggesting a promising and novel TBV target. CRT is a highly conserved protein with similar features in vertebrates and invertebrates including anopheline. We cloned the full-length crt gene from malaria vector, Anopheles stephensi (AsCrt) and explored the interaction of recombinant AsCrt protein, expressed in a prokaryotic system (pGEX-6p-1), with surface proteins of Plasmodium berghei ookinetes by immunofluorescence assay. The cellular localization of AsCrt was determined using the baculovirus expression system. Sequence analysis of the whole cDNA of AsCrt revealed that AsCrt contains an ORF of 1221 bp. The amino acid sequence of AsCrt protein obtained in this study showed 64% homology with similar protein in human. The AsCrt shares the most common features of CRTs from other species. This gene encodes a 406 amino-acid protein with a molecular mass of 46 kDa, which contains a predicted 16 amino-acid signal peptides, conserved cysteine residues, a proline-rich region, and highly acidic C-terminal domain with endoplasmic reticulum retrieval sequence HDEL. The production of GST-AsCrt recombinant protein was confirmed by Western blot analysis using an antibody against the GST protein. The FITC-labeled GST-AsCrt exhibited a significant interaction with P. berghei ookinete surface proteins. Purified recombinant GST-AsCrt, labeled with FITC, displayed specific binding to the surface of P. berghei ookinetes in comparison with control. Moreover, the expression of AsCrt in baculovirus expression system indicated that AsCrt was localized on the surface of Sf9 cells. Our results suggest that AsCrt could be utilized as a potential target for future studies in TBV area for malaria control. 相似文献