Vol. 31 Issue 2/3

Khodran Al-Zahrani, Mirza Baig and Gary Straquadine
Arid climate, high temperatures, limited water supplies; and scarce fresh water resources are prominent features of the ecosystems of the kingdom of Saudi Arabia. Water results sustainability and ensures the survival of the living biota. Since the development of new water resources happens to quite expensive and difficult, therefore conservation of presently available supplies and their wise management by the households, farms and industries seems to be the most suitable option to combat water scarcity. Enormous quantities of water can be saved by employing the simple concepts and principles of Water Demand Management (WDM) in the conservation programs. Realizing the importance of conservation initiatives, the kingdom made generous offers to the consumers in the forms of free distribution of water saving devices and kits. The kingdom offered free friendly technical assistance and support for the installations of the sanitary fittings at the consumers’ residences. These initiatives were also supported by the Extension and Education programs. Extension messages were brought to the water consumers and general public in the pictorial forms. They produced a positive impact and helped reducing the water consumption by 20-30 percent. The present study suggests the continuation of the extension education programs on water conservation.

Taibi Khaled, Taibi Fadhila and Belkhodja Moulay
The performances of two common bean genotypes; Djadida and Tema were tested under NaCl stress. The plants of three weeks were treated for 10 days with NaCl from 30 mM to 150 mM. It appears that salinity produced an imbalance in water relations and affected growth parameters. NaCl application altered roots, leaves and stems mass production and plant water relations. NaCl application affected adversely roots, leaves and stems mass production and altered plant water relations and stomata density. It should be noted that the same physiological behavior was observed for both bean genotypes subjected to salinity which revealed the existence of a quantitative instead of a qualitative difference between the tested genotypes. Here we observed the superiority of the genotype Tema, for maintaining its growth and water relations under salt stress while further researches are necessary to validate our finding under field conditions.

Walid Saleh, Taysier Hujair and Alaa El-Sadek
Because of the importance of the Wadi Gaza as a unique ecosystem in Gaza Governorates, it was declared a nature reserve in June 2000. Wadi Gaza Nature Reserve was established to conserve the wetland ecosystem, to stop or slow the degradation of its natural resources and biological diversity and to promote measures for their eventual rehabilitation. Wadi Gaza represents a unique habitat supporting a rich biodiversity. The Wadi is under threat from many environmental pressures, in particular from sewage generated by recent urban growth within the catchments area, and the use of the Wadi basin as a solid waste dumping site. These polluting sources are not only deteriorating the natural habitat, but also they have an increasing negative impact on the public health of the communities around Wadi Gaza. This study outlines an agenda for investigating the sources of pollution of Wadi Gaza, effects of pollution on Gaza’s ecology and on the health of its inhabitants. Also, to establish an integrated approach for river reclamation management, including technical, administrative and legislative mechanisms for improvement of existing conditions and for ensuring the sustainability of clean Wadi. A capacity building component through training and educational activities are also proposed to proactively address issues of public health/awareness, as well as the protection and sustainability of the Wadi Gaza environment. All the Wadi sources of pollution and their impacts are illustrated in details, these illustrations will be helpful tools to set the suitable solution to each source of pollution and this will give a better understanding of how to solve Wadi Gaza problems. This will lead to the right steps that should be taken in order to improve the environmental situation in Wadi Gaza area.

Muhammad Aqeel Ashraf, Memona Ramzan, Karamat Mahmood and Abdul Wajid
The present study evaluates the nutritive value of different accessions of perennial range grass Cenchrus ciliaris collected from Choilsitan Desert, Pakistan. Different standard methods (Benedict’s quantitative reagent for carbohydrates, crude protein and nitrogen by Kjehldahl method, mineral analysis by flame photometer and estimation of crude fiber by using acid base treatment) are utilised for nutritive analysis. Proximate analysis of plant sample determines that maximum crude protein is present in the range of (13 to 17.5%) and nitrogen contents are in the range of (2.8 to 2.24%). Crude fiber in the range of (24.34 to 39.48%) and crude lipids in the range of (2.3 to 3.2%) are present in the Cenchrus ciliaris. Whereas minerals such as sodium is present in the range between (0.2 to 0.7%), potassium in the range of (3.6 to 6.0%) while lithium was absent. Similarly, reducing sugar present in the range from (2.8 to 4%), non reducing sugar in the range of (2.12 to 3.31%) and total sugars are present in the range of (3.16 to 9.8%). In conclusion, it could be suggested that Cenchrus ciliaris has great medicinal and nutritional importance that could be good sources of some important nutrients for humans and can become a source of poverty alleviation of poor local community of the area.

Mohamed Ait Belaid and Nissreen Altureeki
This research project explains how Three-Dimensional (3D) city models are important and developed all over the world, because it represent the Earth’s surface and give the people the chance to enjoy a virtual visit in cities. It also presents some Techniques used for generating 3D cities, how we used it, and the difficulties we faced. It also shows that The Kingdom of Bahrain started to develop itself and to follow the world in its progress. A mosaic of high resolution aerial photographs was used to reconstruct 3D building models with accurate details. First, we used stereo graphics to determine the rooftops, roads and trees in the 3D window and also we determined the centroid of the roofs. Second, after finishing all roofs we used the tool extrude for extruding the buildings to ground and we used the tool 3D construct to extrude the buildings from the centroid of the roof. So the main goal of this paper was to build 3Dimensional buildings for Manama capital as a case study using available techniques and datasets. The results show that there is many ways to create 3D buildings if the dataset and the software are available, but not all the ways show real 3D city. In the present research we were able to extrude 3D solid buildings with high quality and high accuracy for Manama Center because this work was huge and needed many interpreters or operators with plenty of time.

Fawzi Al-Shyeab
Karyotype of two rodent species, Cricetulus migratorius and Jaculus jaculus were studied from Jordan. Jaculus jaculus karyotype was found to be 2n=48, NFa= 88, while the autosomes consist of five metcentric, 14 submetacenteric and four acrocentric pairs of chromosomes. For Cricetulus migratorius, the karyotype was found to be 2n= 22, NFa= and NF=40, while the autosomes consist of three telocentric, four metacenteric and four acrocentric pairs of chromosomes.

Asim Balbay
In this study, drying of black cumin seeds (BCs) (Nigella sativa) with initial moisture content (MC) of %56.74 (dry basis (d.b)) was investigated in a novel designed fixed bed drying system (isothermal condition) and in a thermo gravimetric analysis system (non-isothermal condition). In isothermal conditions, the drying experiments were carried out at different temperatures (40, 60, and 80 °C) and air velocities (0.25, 0.5 and 1 m/s) and bed heights (14 mm and 28 mm). Several models in literature were selected to fit the experimental data. The fit quality of models was evaluated using the coefficient of determination (R2), sum square error (SSE) and root mean square error (RMSE). Two term model has a good agreement with the experimental data and gave the best results for BCs. The activation energy was calculated to be as 19.92 kJ/mol and effective diffusivity values were calculated to be between 2.85x10-10 and 6.77x10-10 m2/s depending on air temperatures. Furthermore, drying and decomposition behaviours of BCs in thermo gravimetric analysis system were studied in nitrogen flow of 0.850 ml/s and of constant heating rate of 5 °C/min towards 250 °C by means of non-isothermal methods.

Kunaraj Kumarasamy and Seshasayanan Ramachandran
Leading One Detector (LOD) is an important and preliminary stage used for the normalization process in floating point multiplication, floating point addition/subtraction and in logarithmic converters. In this paper the authors propose various gate level architectures for the LOD. The LOD circuit is evolved using the evolutionary algorithm (EA) and using the evolved lower order LOD gate structure, various higher order LOD circuits are constructed using a hierarchical methodology. To obtain better results, the evolutionary algorithm is modified and a novel shuffling operation is performed to prevent the algorithm from settling in the local minima. The convergence and the robustness of the evolutionary algorithm is verified using standard test functions. The constructed LOD circuits are synthesized using Cadence® RTL Compiler® using TSMC 180nm library. The results obtained in terms of cell area and power of the elite LOD circuits show that the proposed evolved-architecture outperforms the existing circuits. The proposed architectures show a maximum of 31.18% improvements in Cell area and 31.27% in power for the 64-bitLOD circuit with an increase of 3.9% in the propagation delay.

Ali Satty and Ali Basher Abdullah Babikir
Dropout is a pervasive problem in longitudinal clinical trials, and it is the result mainly of non-responses due to individuals who leave the study and are therefore lost to follow-up. The current paper deals with incomplete longitudinal clinical trials data when there are dropout. Statistical methods that ignore the mechanism for dropouts are susceptible to biased inference. This article focuses on dropouts missing at random (MAR). The study demonstrates application and the performance of likelihood-based and inverse probability weighting (IPW) in handling dropout in longitudinal continuous responses. The main objective of this paper is to compare the performance of these methods under different dropout rates. Data from a study with individual heart rate as the outcome is used to investigate the performance of the considered methods. Based on this longitudinal clinical trial data, results from IPW will be compared with those obtained from likelihood-based analysis. The performance of these methods are compared in terms of bias and efficiency.

Asim Ismail, Gang Qiao, Feng Zhou and Muhammad Aatiq
Multi-path interference due to boundary reflection and variation of sound speed profile in underwater acoustic channel pose a major barrier to dependable underwater acoustic communications. Based on actual data of northwestern Arabian Sea, multipath impulse response profiles of the area were obtained previously. These channel models are used in spread spectrum communication simulation described in this paper. The transmitted signals, which consist of frames of multiple spreading sequences, are modulated using coherent phase shift keying. The use of multiple pseudo noise sequences (PN) in a single frame allows one to achieve robust communication with a relatively simple receiver structure as compared to traditional single spreading sequence approach. This long code multiple sequence approach also helps in realizing low probability of intercept(LPI) communication. On the receiver side, a rake type receiver collects the energy present in multiple propagation paths after synchronization and Doppler compensation. Channel estimation necessary for the correct working of rake receiver is done together with a Doppler tracking that allows an adaptation to the instantaneous shift. The performance of underwater acoustic communication scheme has been evaluated by simulation. Bit error rate (BER) has been used as a performance metric and effects of different channels, types of noises, data rates, chip rates etc. have been evaluated. The results indicate that such communication systems overcome multipath channel distortion and can perform at low signal to noise ratio. This work can be used as a lead for the practical design of underwater acoustic DSSS communication/telemetry system for this area.