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Excitatory and inhibitory effects of nitric oxide on weight, size, and histological changes of rat cerebellum
Karambaksh A,Noori Mougahi SMH,Hassan Zadeh GR,Tak Zaree N
Tehran University Medical Journal , 2013,
Abstract: Background: Nitric oxide (NO) is produced in different body organs in mammals and numerous physiological and pathological properties are attributed to this small molecule. The precursor of this substance in the body, L-arginine, is synthesized by the enzyme nitric oxide synthase (NOS), and it is catalyzed, and is inhibited by a substance called L-NG-nitroarginine methyl ester (L-NAME). In this study we investigated the qualitative and quantitative effects of nitric oxide on cerebellar histopathology in vivo environment via increasing and decreasing its production.Methods: Forty Wister rats, weighing 200- 250 gr with a mean age of 8 weeks, were divided into 5 groups after making sure the rats were pregnant. Except the control group, the other pregnant groups, respectively received: 2 ml/kg normal saline, 200 mg/kg L-arginine, 20 mg/kg L-NAME and a mixture of the same doses of L-arginine and L-NAME on the third, fourth and fifth days of pregnancy. On day 18 of pregnancy, we anesthetized the rats, excised the cerebellum after craniotomy and fixed the organs in 10% formalin. We later prepared 5 to 6-micron in thickness tissue sections and dyed them by the routine Hematoxylin and eosin (HE) and Masson's Trichrom staining methods before studying them by light microscopy.Results: There was a significant difference between the rats receiving L-arginine and the rats in other groups (P<0.01). Conclusion: This study showed that L-NAME is capable of significantly decreasing the injury caused by nitric oxides in rat cerebellum.
"Stereological analysis of renal glomeruli following chronic lead intoxication in rat during a continuos period of 8 weeks "
"Mahmoodzadeh Sagheb HR,Dezfoulian A,Noori SMH,Heidari Z
Tehran University Medical Journal , 2002,
Abstract: Background: Stereologic methods are used to obtain quantitative information about three dimensional structures from histologic sections. The aim of present study was using new and unbiased stereological techniques to investigated changes in volume and number of glomeruli after chronic lead acetate intoxication. Lead is one of the heavy metals that have adverse effects on renal function. Its effects can involve both renal tubules as well as glomeruli. So many studies based on observation and qualitative reports. Some of which report changes in volume and number of glomeruli. Materials and Methods: Male Wistar rats were randomly divided to four groups (n=9). During a period of 8 weeks, the treatment groups were given 0.5 percent and 1 percent lead acetate in drinking water and the control and sham control were given distilled water and 0.4 percent acetic acid solution respectively. Stereological analysis based on Cavalierie's principle was performed to determine the reference volume (VRefrence), the fraction volume of glomeruli (VVGlom) and total glomerular volume (VTGlom). Furthermore, for estimating the numerical density (NVGlom) and total number of glomeruli (NTGlom), the physical dissector was utilized. Results: Results showed that the number of glomeruli in treatment group which received 1 percent lead acetate in drinking water decreased significantly (P0.05). On the other hand glomerular total volume in both 0.5 percent and 1 percent groups increased significantly in comparison to control and sham control groups (P=0.000). Conclusion: This experiment is in agreement with other qualitative reports by using unbiased method of stereological methods and showed changes in volume and number of glomeruli following lead acetate intoxication.
BSDCH: New Chain Routing Protocol with Best Selection Double Cluster Head in Wireless Sensor Networks  [PDF]
Majid Noori, Alireza Khoshtarash
Wireless Sensor Network (WSN) , 2013, DOI: 10.4236/wsn.2013.52002
Abstract:

The Optimum use of energy is one of the significant needs in wireless sensor networks, because sensor devices would usually use the battery power. In this article, we give the suggested routing algorithm (BSDCH) with determining an optimum routine due to the energy use and the number of passed hobs. To transfer date from nodes’ sensor to BS (Base Station), data sending has been utilized in chains. In BSDCH algorithm, the nodes’ space is divided into several regions. In this article, each part is called a cluster. In each cluster, a node which is the best due to energy and distance comparison with other cluster nodes it is continuously selected with a given Formula (4) which is called main CH (Cluster Head) and forms a chain in that cluster and in each node cluster, it is selected by Formula (5) as secondary CH with the least distance and the best situation to BS and main CH. the secondary CH task is to receive data from the main CH and send data to the BS. As far as the main cluster head would waste too much energy to send data to BS, so to send data through secondary CH, we can keep main CH energy for more time. In the time of sending data from nodes to main CH, a multi chain is utilized. In the time of making nodes’ chain, nods are connected straight into its main CH radius and other nodes are connected in their sending radius which would have the least distance to main CH. Finally, also, BSDCH has been compared with PEGASIS [1] and PDCH [2]. The simulation results are shown which are indicator of a better BSDCH performance.

Analytical image reconstruction methods in emission tomography  [PDF]
Mahsa Noori Asl, Alireza Sadremomtaz
Journal of Biomedical Science and Engineering (JBiSE) , 2013, DOI: 10.4236/jbise.2013.61013
Abstract:

Data collected in two-dimensional projections give planar images of object at each projection angle. To obtain information along the depth of the object, tomographic images are reconstructed using these projections. There are basically two approaches to solve the problem of reconstruction: analytical and iterative, each one presenting its own advantages and limitations. This paper provides a detailed introduction and comparison to four analytical image reconstruction methods including Fourier transformation, simple back-projection, back-projection filtering and filtered back-projection.

Distributed Multi-objective Multidisciplinary Design Optimization Algorithms
Amir Noori
Mathematics , 2012,
Abstract: This work proposes multi-agent systems setting for concurrent engineering system design optimization and gradually paves the way towards examining graph theoretic constructs in the context of multidisciplinary design optimization problem. The flow of the algorithm can be described as follow; generated estimates of the optimal (shared design) variables are exchanged locally with neighbor subspaces and then updated by computing a weighted sum of the local and received estimates. To comply with the consistency requirement, the resultant values are projected to local constraint sets. By employing the existing rules and results of the field, it has shown that the dual task of reaching consensus and asymptotic convergence of the algorithms to locally and globally optimal and consistent designs can be achieved. Finally, simulations are provided to illustrate the effectiveness and capability of the presented framework.
On the Relation between Centrality Measures and Consensus Algorithms
Amir Noori
Mathematics , 2012,
Abstract: This paper introduces some tools from graph theory and distributed consensus algorithms to construct an optimal, yet robust, hierarchical information sharing structure for large-scale decision making and control problems. The proposed method is motivated by the robustness and optimality of leaf-venation patterns. We introduce a new class of centrality measures which are built based on the degree distribution of nodes within network graph. Furthermore, the proposed measure is used to select the appropriate weight of the corresponding consensus algorithm. To this end, an implicit hierarchical structure is derived that control the flow of information in different situations. In addition, the performance analysis of the proposed measure with respect to other standard measures is performed to investigate the convergence and asymptotic behavior of the measure. Gas Transmission Network is served as our test-bed to demonstrate the applicability and the efficiently of the method.
Numerical Solution of a Class of Nonlinear Optimal Control Problems Using Linearization and Discretization  [PDF]
Mohammad Hadi Noori Skandari, Emran Tohidi
Applied Mathematics (AM) , 2011, DOI: 10.4236/am.2011.25085
Abstract: In this paper, a new approach using linear combination property of intervals and discretization is proposed to solve a class of nonlinear optimal control problems, containing a nonlinear system and linear functional, in three phases. In the first phase, using linear combination property of intervals, changes nonlinear system to an equivalent linear system, in the second phase, using discretization method, the attained problem is converted to a linear programming problem, and in the third phase, the latter problem will be solved by linear programming methods. In addition, efficiency of our approach is confirmed by some numerical examples.
Mitigating Time Interval Error (TIE) in High-Speed Baseband Digital Transports: Design for Delay Compensation at Baseband Infrastructure of Smart-Phones Using Fractal Dispersive Delay-Lines  [PDF]
Perambur S. Neelakanta, Aziz U. Noori
Circuits and Systems (CS) , 2014, DOI: 10.4236/cs.2014.55013
Abstract:

A major concern in modern smart-phones and hand-held devices is a way of mitigating the time interval error (TIE) perceived at high-speed digital transits along the traces of the circuit-board (rigid and or flexible) used in baseband infrastructures. Indicated here is a way of adopting a planar fractal inductor configuration to improvise the necessary time-delay in the transits of digital signal phase jitter and reduce the TIE. This paper addresses systematic design considerations on fractal inductor geometry commensurate with practical aspects of its implementation as delaylines in the high-speed digital transports at the baseband operations of smart-phone infrastructures. Experimental results obtained from a test module are presented to illustrate the efficacy of the design and acceptable delay performance of the test structure commensurate with the digital transports of interest.

On the achievable rates of symmetric Gaussian multi-way relay channels
Moslem Noori and Masoud Ardakani
EURASIP Journal on Wireless Communications and Networking , 2013, DOI: 10.1186/1687-1499-2013-11
Abstract: Considering a symmetric Gaussian multi-way relay channel (MWRC) with K users, this work compares two transmission strategies, namely one-way relaying (OWR) and multi-way relaying (MWR), in terms of their achievable rates. While in OWR, only one user acts as data source at each time and transmits in the uplink channel access, users can make simultaneous transmissions in MWR. First, we prove that for MWR, lattice-based relaying ensures a gap less than bit from the capacity upper bound while MWR based on decode-and-forward (DF) or amplify-and-forward (AF) is unable to guarantees this rate gap. For DF and AF, we identify situations where they also have a rate gap less than bit. Later, we show that although MWR has higher relaying complexity, surprisingly, it can be outperformed by OWR depending on K and the system SNR. Summarily speaking, for large K and small users’ transmit power, OWR usually provides higher rates than MWR.
Evaluation of MIMO Channel Capacity in Indoor Environments Using Vector Parabolic Equation Method
Narges Noori;Homayoon Oraizi
PIER B , 2008, DOI: 10.2528/PIERB07121903
Abstract: In this paper, the vector parabolic equation method (VPEM) is used to investigate the Shannon capacity of multiple-input multiple-output (MIMO) communication systems in indoor corridors. This deterministic three-dimensional (3-D) full-wave method is capable to demonstrate the effects of antennas and propagation environment on the channel capacity. The VPEM can model any field depolarization effects which are caused by the corridor walls. This method is particularly useful for evaluation of MIMO channel capacity in corridors with local narrowing of cross section. The channel capacity is computed for both single and hybrid polarizations and simulation results are compared with those obtained by the ray tracing method.
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