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The vertical distribution of phytoplankton in stratified water columns (upper 150 m), was studied at five stations around the cap Juby area, Moroccan Atlantic sea, during four periods in 2009. Five depth levels were sampled: 5, 25, 50m for coastal stations and up to 90, 150m for offshore stations. The vertical variability of the physical parameters was analyzed to assess the impact of hydrological fluctuations on phytoplankton vertical distribution. The maximal densities are noted at the surface in April and June, where the upwelling activity reaches its maximum, manifested by cold-water temperature, low salinities and an intense intake of nutrients. These observations are confirmed by the vertical distribution of dominant species, such as Thalassiosira spp, Leptocylindrus danicus, Leptocylindrus minimus, Nitzschia spp and Alexandrium spp. Indeed, these five common and frequently occurring phytoplankton species showed maximal proliferation, on the upper layers, in upwelling periods. In February and October, a considerable stratification of all parameters is noticed, leading to an unremarkable vertical variability in phytoplankton distribution.

Existing and in recent times proposed clustering algorithms are studied and it is known that the k-means clustering method is mostly used for clustering of data due to its reduction of time complexity. But the foremost drawback of k-means algorithm is that it suffers from sensitivity of outliers which may deform the distribution of data owing to the significant values. The drawback of the k-means algorithm is resolved by k-medoids method where the novel approach uses user defined value for k. As a result, if the number of clusters is not chosen suitably, the accuracy will be minimized. Even, K-medoids algorithm does not scale well for huge data set. In order to overcome the above stated limitations, a new grid based clustering method is proposed, where time complexity of proposed algorithm is depending on the number of cells. Simulation results show that, the proposed approach has less time complexity and provides natural clustering method which scales well for large dataset.

The applications of audio and video compression are limitless and the ISO has done well to provide standards which are appropriate to the wide range of possible compression products. MPEG coding embraces video pictures from the tiny screen of a videophone to the high-definition images needed for electronic cinema. Audio coding stretches from speech-grade mono to multichannel surround sound. This paper presents an overview of the video compression standards related to the MPEG family. MPEG-7 and MPEG-21 are specially covered including its latest standards. MPEG-7 is mainly used for object descriptions and MPEG-21 is for DRM (Digital Rights Management).

Sedimento logical analysis methods to study historical events and environmental sections of these dimentary basins of the natural sciences is common. Analysis of sedimentary sections particularly Quaternaryse dements can be revealed climatic and environmental conditions of the area and uncover favorable view of the environmental conditions. The purpose of this study is Analysis of Bayazeh sediments and Chopanan sediments and explanation of their formation environment. In this study the physical properties of these diments containing Granulometry, Analysis, Calcimetry, Transparent rate, rounding rate and chemical properties, including the amount of lime, pH, EC were compared and the results indicated that Chopanan sediments were aeolian sediments and deposited in dry environment and Bayazeh sediments deposits in an aquatic environment. This causes indicate that in the past era there was a local pond in the Bayazeh.

The in vitro antibacterial activity of flavonoid and alkaloid extracts of various plant parts of V. negundo and A. paniculata was investigated using Disc Diffusion Assay against four Gram negative (E. aerogens, R. planticola, A. tumefaciens and K. pneumoniae) and one Gram positive bacteria (B. subtilis). Minimum inhibitory concentration of the extracts was evaluated by micro broth dilution method, while minimum bactericidal concentrations were determined by sub culturing the relevant samples. The extracts exhibited antimicrobial activities with zones of inhibition ranging from 9 to 23.5 mm. A. tumefaciens was found to be most susceptible organism in the investigation against which all the extracts showed positive response. Stem free flavonoid extract of V. negundo and stem bound flavonoid extract of A. paniculata was recorded as most active extract as it showed significant zone of inhibition against all the tested pathogens. The range of MIC and MBC was recorded 1.25-0.039mg/ml. Results of the present study reveal that extracts of both the selected plants are showing great antimicrobial potential against tested pathogen, and may be exploited for future antibacterial drugs.

This paper focuses on the bidirectional associative memory its features and the future aspects and the current context of application. BAM is a type of neural network. Artificial neural network (Ann’s) resembled the human nervous system, with algorithms consisting of weighted interconnecting processing units (like neural map of the human brain). To address a particular problem using Ann’s, the interrelated connections are tuned and the value of weights between units is needed. Neural network is a new unexplored topic of interest for the computer scientists. Bam comes under recurrent types of network called Hopfield network. BAM is a resonance model, in the sense that information is passed back and forth between two layers of units until a stable sate is reached. The Hopfield network is said to be auto associative, because it uses a partial and noisy pattern to recall the best match of itself. BAM includes: ASSOCIATIVE NEURAL MEMORIES: Associative neural memories are a class of artificial neural networks (connectionist nets) which have gained substantial attention relative to other neural net paradigms. Associative memories have been the subject of research. NOISE TOLERANCY: This paper analyzes the sensitivity to noise in BAM (Bidirectional Associative Memory), and then proves the noise immunity of BAM relates not only to the minimum absolute value of net inputs (MAV) but also to the variance of weights associated with synapse connections.

The present study was conducted to investigate the association between some single nucleotide polymorphisms in hspa1b and hspa1l genes with the incidence of severe oligozoospermia in Iraq. Blood samples were obtained from Kamal Al-Samraee hospital for fertility, infertility and in vitro fertilization –Baghdad - Iraq .Blood samples were collected from 50 of severe oligozoospermic patients and 50 apparently healthy subjects (control group). Data related with age, smoking status and semen parameters (concentration, semen volume, sperm motility and sperm abnormality) were obtained using questioner forma for each patient. DNA was extracted from all blood samples by using Promega Kit ,then the extracted DNA was used for amplification of targeted fragments genes using PCR.PCR products were incubate with the restriction enzymes used in this study(PstI and NcoI ,respectively). Then subject to electrophoresis for identification the genotypes of rs1061581 G > A SNP in hspa1b gene and rs2227956 C > T SNP in gene. The PCR products of positive samples were sent for sequencing to confirm the results. . As related with rs1061581 G 0.05) higher in control group than in severe oligozoospermic patients (48 versus 40% ,respectively).Whereas , the frequency of AA genotype was significantly (p > 0.05) higher in severe oligozoospermic patients group than in control group (38 versus 24% ,respectively).G allele frequency was 52 and 42% ; and A allele frequency was 48 and 58 % in control and severe oligozoospermic patients group , respectively. As related with rs2227956 C > T SNP (hspa1l gene) , the frequency of TT genotype was significantly(p<0.05) higher in severe oligozoospermic patients group than in control group( 42 versus 34 % ,respectively) .C allele frequency was 41 and 35% ; and T allele frequency was 59 and 65% in control and severe oligozoospermic patients group ,respectively. It can be concluded that homozygous mutants (AA genotype in rs1061581 G

Voltage instability problems have become important issues in unbalanced distribution networks. In this paper, a new bus positive sequence voltage index of Vcollapse/Vbase-load is introduced to identify the weakest three-phase buses in unbalanced three-phase distribution networks. First, the proposed ranking index is validated based on grid losses and PV curves without and with compensation devices. Then, the index is utilized to place three-phase DG without and with SVC devices at the three-phase weakest buses of the modified IEEE unbalanced 13 node test feeder using the DIgSILENT Power Factory software. Finally, simulation results are presented to show the application of the proposed approach in improving voltage stability and increasing the maximum loading factor under unbalanced loading and/or network conditions.

Kashan playa, Located in the west of Central Desert of Iran, has been subjected to severe desertification problems. Most of these problems are due to human activities, overgrazing, sand dune mobility, soil salinity and ground water depletion. Monitoring desertification, land degradation and land cover requires rapid and accurate procedures. Remotely sensed satellite technology allows land degradation processes to be monitored over time. Two Landsat TM/ETM+ satellite images for 12 years period (1990-2002) with field observations were provided basic information for mapping of the extend and monitoring of the Kashan playa in central desert of Iran. Several change detection techniques such as image differencing, vegetation change analysis, principal component analysis and classification comparison have been applied to the data. Maximum Likelihood classification analysis showed a kappa coefficient accuracy of 86% and 82% for the TM and ETM+ images. Results revealed that about 35 % of the study area mostly salty lands and fixed sand dune has been rapidly changed. The overall rate changes of the desert lands and vegetation are about 7275 and 62 ha year^-1 respectively.

The Next Generation Wireless Networks (NGWN) are heterogeneous in nature and Call Admission Control (CAC) in NGWN is a challenging problem. User differentiation is becoming increasingly important to the service providers as Quality of Service (QoS) requirements vary amongst users. The number of users in the network is directly controlled by CAC and hence must be carefully designed to guarantee the varying QoS needs of users. This paper proposes a channel partitioning model for CAC in NGWN by taking into account the users QoS needs and the simulation results for the call blocking probability of different user classes is presented.