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Rajashree P.V.,Kongunadu Arts and Science College | Sam K.G.,Gulf College
Research Journal of Medicinal Plant | Year: 2011

Alcoholic extracts of four Indian medicinal plants Kaempferia galanga (Zingiberacae) Linn. Clerodendrum viscosum (Verbenaceae) Linn., Jatropha curcus (Euphorbiaceae) Linn, and Lens culinaris (Fabaceae) Linn, were subjected to preliminary screening for their antitumor activity. Acute toxicity studies in mice revealed that all the ethanolic extracts were safe up to a dose level of 500, 1000, 2000 mg kg1-1 body weight. Preliminary short term anticancer screening, by brine shrimp lethality test, potato disc inhibition and DLA cell line assay, proved that K. galanga, exhibited significant antitumor activity and it was therefore, selected as a candidate plant for more detailed phytochemical and mechanistic studies. Brine shrimp lethality assay revealed that K. galanga extract inhibited tumor development at a lower concentration LC50 = 684.2 jig mL-1 as compared to 901, 866 and 5436 jig mL-1 for the extracts of C. viscosum, J. curcus and L. culnaris, respectively. Alcoholic extract of K. galanga significantly (p<0.001) inhibited Agrobacterium induced tumors in potato discs with average tumor count of 15, 11, 8.0, 6.0 and 4.8 at concentrations of 10, 20, 30, 40 and 50 jig mL-1, respectively. K. galanga extract regress tumors equipotently to vincristine in Dalton Lymphoma Ascitic (DLA) cell tumor bearing mice. There was a statistically significant (p<0.001) higher mean increase in Percentage Life Span (ILS) in rats treated with K. galanga extract 73.27±10.51 with median value of 69.85% as compared to Vincristine group 53.84±11.94 with median 54.25%. Preliminary phytochemical tests of the candidate plant K. galanga indicated the presence of flavonoids, suggesting a prominent role for them in anticancer activity. © 2011 Academic Journals Inc.

Harris K.J.,Florida State University | Murphy K.S.,University of Central Florida | DiPietro R.B.,University of South Carolina | Rivera G.L.,Gulf College
International Journal of Hospitality Management | Year: 2015

This study examined the proposition that cultural differences between ethnic-operated restaurants in high tourism areas of the United States (US) compared to non-ethnic operated restaurants explains the differences in food safety and sanitation inspection scores in five US cities considered popular tourism destinations. It was hypothesized that ethnic-operated restaurants, composed of people from different cultural norms than that of the indigenous US population, would result in significantly higher rates of critical regulatory violations than non-ethnic-operated restaurants. Food safety inspection data was obtained from five cities in the west, mid-west, east and two from the south for the years 2009 and 2010. Results confirmed the hypotheses that ethnic-operated restaurants have significantly higher rates of inspection and critical violations. Implications for regulators, trainers, ethnic restaurants and organizations seeking to manage diversity are discussed. © 2015 Published by Elsevier Ltd.

Harris K.J.,Florida State University | DiPietro R.B.,University of South Carolina | Murphy K.S.,University of Central Florida | Rivera G.,Gulf College
International Journal of Hospitality Management | Year: 2014

This study explores the relationship between the number of critical food safety violations and the restaurant's status as either a chain or independent foodservice provider and location. The State of Florida categorized the restaurant operations according to the type of license obtained, chain or independent. Chain restaurants are defined as multi-unit restaurants owned or operated by the same company or individual that total seven locations or more. Data for the current study was retrieved from the public records for the fiscal years 2009-2010 and 2010-2011. The study found that both the aggregate number of critical violations and risk factors and the number of individual critical violations and risk factors were significantly different among chain and non-chain restaurants in the state of Florida. Results indicate that the number of critical violations received is impacted by both the location of the restaurant and whether the restaurant is independently operated or a chain. The current study assists in explaining underlying reasons for repeated food safety violations despite Florida's required food safety training certification of restaurant managers and training of their staff; providing implications for academics and foodservice practitioners alike. © 2013 Elsevier Ltd.

Eller K.T.,Florida State University | Burnett W.C.,Florida State University | Fitzhugh L.M.,St. Andrew Bay Resource Management Association | Fitzhugh L.M.,Gulf College | Chanton J.P.,Florida State University
Estuaries and Coasts | Year: 2014

Activity ratios (AR) of radium isotopes have been used with success to constrain estimates of water ages and to approximate residence times in coastal waters. We compared two common radium sampling methods (grab sampling and stationary moorings) to estimate water ages and the residence time of St. Andrew Bay waters in northwest Florida, USA. Both sampling methods utilize manganese dioxide fibers ("Mn fibers") to adsorb dissolved radium from the water column. Grab samples capture radium activities at a discrete time while moorings integrate radium activities over longer deployments. The two methods yielded similar results in this study and thus both approaches are useful for water age comparisons and residence time approximations. However, since radium often varies as a function of tidal stage, deploying moorings over a complete tidal cycle is the preferred approach. An estimated residence time for North Bay and West Bay of 8-11 days was approximated using ARs for both ex224Ra/223Ra and ex224Ra/228Ra. Some complications were introduced as St. Andrew Bay is a tidally dominated, rather than a river-dominated bay system where this method has previously been applied. The largest freshwater source to this bay system is from a man-made reservoir, with an average freshwater flow of only 20 m3 s-1. The activity concentrations and ARs measured by both sampling methods suggest that while the reservoir is the prominent radium source, it is not the only radium source. Nonetheless, a tidal mixing model applied to the western half of the system yielded an approximate flushing time of 10-12 days, similar to that derived from our radium-based water age approach. © 2013 Coastal and Estuarine Research Federation.

Ali R.,University of Jordan | Neill P.A.,University of Nevada, Reno | Beiersdorfer P.,Lawrence Livermore National Laboratory | Harris C.L.,Gulf College | And 2 more authors.
Astrophysical Journal Letters | Year: 2010

Experimental and theoretical state-selective X-ray spectra resulting from single-electron capture in charge exchange (CX) collisions of Ne10+ with He, Ne, and Ar are presented for a collision velocity of 933 km s -1 (4.54 keV nucleon-1), comparable to the highest velocity components of the fast solar wind. The experimental spectra were obtained by detecting scattered projectiles, target recoil ions, and X-rays in coincidence; with simultaneous determination of the recoil ion momenta. Use and interpretation of these spectra are free from the complications of non-coincident total X-ray measurements that do not differentiate between the primary reaction channels. The spectra offer the opportunity to critically test the ability of CX theories to describe such interactions at the quantum orbital angular momentum level of the final projectile ion. To this end, new classical trajectory Monte Carlo calculations are compared here with the measurements. The current work demonstrates that modeling of cometary, heliospheric, planetary, and laboratory X-ray emission based on approximate state-selective CX models may result in erroneous conclusions and deductions of relevant parameters. © 2010. The American Astronomical Society. All rights reserved.

Ali R.,University of Jordan | Beiersdorfer P.,Lawrence Livermore National Laboratory | Harris C.L.,Gulf College | Neill P.A.,University of Nevada, Reno
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2016

Charge-exchange collisions of slow Ne10+ ions with He, Ne, and Ar targets were studied with simultaneous x-ray and cold-target recoil-ion-momentum spectroscopy proving the contribution of several mechanisms to the radiative stabilization of apparent (4,4) doubly excited states for He and Ne targets and of (5,6) states for Ar. In particular, the stabilization efficiency of the mechanism of dynamic auto-transfer to Rydberg states is confirmed. Moreover, we present evidence for direct radiative decays of (4,4) states populated in collisions with He, which is an experimental indication of the population of so-called unnatural-parity states in such collisions. These mechanisms lead to the emission of x-rays that have considerably higher energies than those predicted by current spectral models and may explain recent observations of anomalously large x-ray emission from Rydberg levels. © 2016 American Physical Society.

Adarbah H.Y.,Gulf College | Linfoot S.,De Montfort University
Proceedings 2013 IEEE 3rd International Conference on Consumer Electronics - Berlin, ICCE-Berlin 2013 | Year: 2013

A Mobile Ad hoc NETwork is built by mobile consumer devices but its efficiency is limited by the battery life. The challenge facing mobile consumer device designers is that the discovery phase of the routing process when attempting to establish a mobile ad hoc network tends to put the highest strain on the battery of the device. They tend to be affected by routing packets which need to be sent during the re-built the route. This paper is concerned with studying the performance analysis of Routing Overhead and its messages in Route discovery based on physical module such as noise power and MAC module such types of access as well as the effect of routing overhead on the lifetime of networks. First study focuses on physical factors in terms of The Signal to Interference plus Noise Ratio. In this study the results shows that there are major effects on the routing overhead of MANETs, once the PHY factors are considered because of re-implementing the route discovery phase more often. Second study focuses on MAC factors in terms of carrier sensing ranges (Virtual carrier sensing RTS/CTS, Physical carrier sensing). From the results can be proposed that that the probability of collision in the channel can be reduced by tuning the carrier sensing thresholds as well as the routing overhead becomes better. It proposes that the power consumption could be enhanced by reduce unnecessary sending and receiving between nodes in route discovery phase (routing overhead) and the factors of PHY, MAC modules need to be considered during the design of routing protocols, as well as the relationships between routing packets and the power consumption have been identified. © 2013 IEEE.

Obaidy M.A.,Gulf College | Ayesh A.,De Montfort University
Sustainable Computing: Informatics and Systems | Year: 2015

Abstract In this work we are presenting the design of an intelligent hybrid optimization algorithm which is based on Evolutionary Computation and Swarm Intelligence to increase the life time of mobile wireless sensor networks (WSNs). It is composed of two phases; Phase-1 is designed to divide the sensor nodes into independent clusters by using Genetic Algorithms (GAs) to minimise the overall communication distance between the sensor-nodes and the sink-point. This will decrease the energy consumption for the entire network. Phase-2 which is based on Particle Swarm Optimization (PSO) is designed to keep the optimum distribution of sensors while the mobile sensor network is directed as a swarm to achieve a given goal. One of the main strengths in the presented algorithm is that the number of clusters within the sensor network is not predefined, this gives more flexibility for the nodes' deployment in the sensor network. Another strength is that sensors' density is not necessary to be uniformly distributed among the clusters, since in some applications constraints, the sensors need to be deployed in different densities depending on the nature of the application domain. Although traditionally Wireless Sensor Network have been regarded as static sensor arrays used mainly for environmental monitoring, recently, its applications have undergone a paradigm shift from static to more dynamic environments, where nodes are attached to moving objects, people or animals. Applications that use WSNs in motion are broad, ranging from transport and logistics to animal monitoring, health care and military. These application domains have a number of characteristics that challenge the algorithmic design of WSNs. © 2014 Elsevier Inc. All rights reserved.

Al-Radaideh Q.A.,Yarmouk University | Masri K.H.,Gulf College
Computer Standards and Interfaces | Year: 2011

Classical mobile phone keypads which consist of 12 buttons are commonly used to write short text messages through two common methods, the multi-tap and the predictive text entry. For the Arabic language mobile keypads, all Arabic letters are distributed over the 8 buttons of the keypad where three or more letters share the same button. In this paper, a new text entry environment is proposed. The environment includes two proposed improved approaches for Arabic language messages to make the multi-tap text entry method faster and easier. The first approach is based on the idea of remapping the distribution of Arabic letters on the keypad according to the frequency of letters. In the second approach, a bi-Gram based method is used to predict the next letter to be typed automatically. The proposed approaches are evaluated using a corpus of 1514 real Arabic text messages. Several experiments were conducted to evaluate the proposed text entry environment. The results of the experiments have showed that using the proposed remapped keypad is faster and consumes less effort in comparison to the classical keypad. © 2010 Elsevier B.V. All rights reserved.

Al-Azawi R.,Gulf College | Ayesh A.,University of Leicester
2015 International Conference on Open Source Software Computing, OSSCOM 2015 | Year: 2015

This paper describes a case study of how Agent Oriented Agile Based (AOAB) development methodology was implemented in mobile computing module to create game as a part of the module assessment requirements. Games can be used in higher education in many ways to increase students participation, enable variation in how lectures are taught and to increase students interest when they create their own game. We provide a new game development methodology and integrated with mobile computing module. The experience described in this paper is based on the feedback from the module staff member, students feedback, final student report and finally module evaluation report by students. The evaluation shows that the students who used AOAB methodology provide a better result rather than groups who used Agile game development methodology in game creation. Finally, we describe the benefit of using game in higher education and how we could enhance students progress in their study. © 2015 IEEE.

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