University of Jordan

About: University of Jordan is a education organization based out in Amman, Jordan. It is known for research contribution in the topics: Population & Medicine. The organization has 7796 authors who have published 13764 publications receiving 213526 citations.

BPA-CRP: A balanced power-aware clustering and routing protocol for wireless sensor networks

Abstract: Advances in sensor technology has enabled the development of small, relatively inexpensive, and low-power sensors, which are connected together through wireless medium, forming what is so called Wireless Sensor Networks (WSNs). WSNs have huge number of applications out of which military target tracking and surveillance. However, sensors operate on limited power resources; therefore, utilizing those resources has brought the attention of current researchers. In this paper, we propose a Balanced Power-Aware Clustering and Routing protocol (BPA-CRP). Specifically, we developed a batch-based clustering and routing protocol in which the network topology divides the sensor field into equal-sized layers and clusters. The clustering algorithm allows any cluster to operate multiple rounds (a batch) without any need for set-up overhead. BPA-CRP assigns four different broadcast ranges for each sensor. Not only to this extent, but rather, BPA-CRP introduces a routing algorithm in which a new node role called “Forwarder” which is capable of relaying the collected data from the layer, it resides in, and far away forwarders toward the base station. As a complementary to prior described protocol, BPA-CRP proposes that a batch ends when the energy of any of the forwarders dips below a certain threshold. Additionally, BPA-CRP introduces the “Only Normal” operation mode, which primarily prevents exhausted nodes from serving as cluster heads or forwarders any longer. In fact, all of just mentioned enhancements not only are energy-aware, but also contributes in accomplishing efficient load balancing. Finally, we put proper node death-handling rules, which guarantee that each node dies smoothly without any loss of data, neither causing disruption for the network. Simulation results showed an exceptional performance of BPA-CRP over different relevant works in terms of network lifetime and network energy utilization. The load balancing capability of BPA-CRP is validated as well.

Organic matter release by dominant hermatypic corals of the Northern Red Sea

Abstract: Particulate organic matter (POM) and dissolved organic carbon (DOC) release by six dominant hermatypic coral genera (Acropora, Fungia, Goniastrea, Millepora, Pocillopora and Stylophora) were measured under undisturbed conditions by laboratory incubations during four seasonal expeditions to the Northern Red Sea. In addition, the influence of environmental factors (water temperature, light availability and ambient inorganic nutrient concentrations) was evaluated. Particulate organic carbon (POC) and particulate nitrogen (PN) release were always detectable and genus-specific, with Stylophora releasing most POM (6.5 mg POC and 0.5 mg PN m−2 coral surface area h−1) during all seasons. The fire coral Millepora released significantly less POM (0.3 mg POC and 0.04 mg PN m−2 coral surface area h−1) than all investigated anthozoan genera. The average POC:PN ratio of POM released by all coral genera was 12 ± 1, indicating high carbon/low nitrogen content of coral-derived organic matter. POM release showed little seasonal variation, but average values of POC and PN release rates correlated with water temperature, light availability and ambient nitrate concentrations. DOC net release and elevated DOC:POC ratios were detectable for Acropora, Goniastrea and Millepora, revealing maximum values for Acropora (30.7 mg DOC m−2 coral surface area h−1), whilst predominant DOC uptake was observed for Pocillopora, Fungia and Stylophora. Depth-mediated light availability influenced DOC fluxes of Acropora and Fungia, while fluctuations in water temperature and ambient inorganic nutrient concentrations showed no correlation. These comprehensive data provide an important basis for the understanding of coral reef organic matter dynamics and relevant environmental factors.

Assessment of groundwater vulnerability in the coastal region of Oman using DRASTIC index method in GIS environment.

Abstract: A study was carried out to develop a vulnerability map for Barka region in the North Batina of Oman using DRASTIC vulnerability index method in GIS environment. DRASTIC layers were created using data from published reports and the seven DRASTIC layers were processed by the ArcGIS geographic information system. Finally, DRASTIC maps were created for 1995 and 2004 to understand the long-term changes in the vulnerability index. DRASTIC vulnerability maps were evaluated using groundwater quality data such as chemical and biological parameters. DRASTIC vulnerability maps of 1995 and 2004 indicate that the northern part of Barka is more vulnerable to pollution than southern part and the central part of Barka also shows high relative vulnerability which is mostly related to the high conductivity values. Moreover, the changes in water level due to high abstraction rate of groundwater reflect in the vulnerability maps and low vulnerability area is increased in the southern part during 2004 compared to 1995. Moreover, regional distribution maps of nitrate, chloride and total and fecal coliforms are well correlated with DRASTIC vulnerability maps. In contrast to this, even though DRASTIC method predicted the central part of the study region is highly vulnerable, both chemical and biological parameters show lower concentrations in this region compared to coastal belt, which is mainly due to agricultural and urban development. In Barka, urban development and agricultural activities are very high in coastal region compared to southern and central part of the study area. Hence, this study concluded that DRASTIC method is also applicable in coastal region having ubiquitous contamination sources.

Oral candidosis in patients with removable dentures.

Abstract: The prevalence of Candida species with and without denture-related stomatitis were evaluated in 167 Jordanian patients. The study revealed that 47 (28%) of the patients with denture-related stomatitis were colonized with Candida species (clinical group). Candida albicans was responsible for most cases of denture-related stomatitis (72%), and it was the only species capable of secreting aspartic proteinases. The study also indicated that candidal colonization was not influenced by predisposing haematological deficiencies, as both the clinical and control patient groups showed comparable haematological parameters and the differences were not significant (P > 0.05). All Candida species isolates were 100% susceptible to amphotericin B, while these isolates were less susceptible (25-75%) to fluconazole.