News Article | November 2, 2016
Athens, Ga. - An interdisciplinary team of researchers at the University of Georgia has developed a new technology that may help scientists better understand how an individual cell synchronizes its biological clock with other cells. While scientists have previously observed synchronization at the macroscopic level of millions of cells, the UGA researchers say this is the first time anyone has been able to observe single cells syncing their circadian rhythms with each other. Circadian rhythm is a roughly 24-hour cycle in the physiological process of living things, including animals, plants and fungi. This daily cycle is linked to sleeping and feeding patterns, hormone production, cell regeneration and other biological activities. The new microfluidic technology developed by the UGA researchers--in which individual cells are encapsulated in droplets and tagged with a fluorescent protein--provides scientists with a stable platform to track tens of thousands of cells with single-cell precision, according to Zhaojie Deng, a Ph.D. candidate in the College of Engineering and the lead author of the study. The team's findings were published online Oct. 27 in the journal Scientific Reports. In the study, Deng and her colleagues were able to monitor more than 25,000 individual cells of Neurospora crassa, a type of bread mold often used as a research model. Not only did they confirm that many cells had a distinct circadian rhythm, they also observed the individual cells synching their rhythms over time. The researchers say the new process outlined in the study also will allow scientists to observe and gather data from cells over a longer period of time than has been possible in the past. "This technology allows us to collect a tremendous amount of data as we try to make sense of the cells' circadian rhythm," said Leidong Mao, an associate professor in the College of Engineering and one of the study's corresponding authors. "We've been able to stabilize cells for up to 10 days, while in the past scientists were only able to gather data from individual cells for approximately 48 hours." Mao says monitoring large numbers of N. crassa cells is difficult work because each cell is only 10 microns in diameter. By comparison, the average cross-section of a human hair is about 100 microns. "If you want to measure tens of thousands of individual cells at the same time, each cell must be extremely stable and stay in place for up to 10 days or you lose track of them," Mao said. The researchers say their findings may eventually lead to advances in a number of areas where the circadian rhythms of organisms play a role. "You might want to exploit the biological clock of algae to make biofuel reactors more efficient or you might want to understand the synchronization phenomenon of agricultural pests such as locusts," said Jonathan Arnold, a professor in the Franklin College of Arts and Sciences' department of genetics and a corresponding author of the study. The team's study provides tools and approaches that might even shed light on the synchronization of cells in the master clock of the human brain, according to Arnold. He notes the behavior of the human master clock has been tied to health problems such as heart disease and cancer. In addition to Deng, Mao and Arnold, the research team includes Taotao Zhu, a Ph.D. student in the College of Engineering; Sam Arsenault, a Ph.D. student in the department of entomology; Cristian Caranica, a Ph.D. student in the department of statistics; James Griffith, a research coordinator in the department of genetics and in the College of Agricultural and Environmental Sciences; Heinz-Bernd Schüttler, a professor in the department of physics and astronomy; and Ahmad Al-Omari, an associate professor in the department of biomedical systems and informatics engineering at Yarmouk University in Jordan. The full study is available online at http://www. . This research is supported by the National Science Foundation under Grant Nos. 1150042, 1242030, 1359095, 1426834; and by the National Institute of General Medical Sciences of the National Institutes of Health under Award No. R21GM104528.
Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: KBBE.2010.3.5-03 | Award Amount: 3.91M | Year: 2011
The project ULIXES aims to unravel, categorize, catalogue, exploit and manage the microbial diversity available in the Mediterranean Sea for addressing bioremediation of polluted marine sites. The idea behind ULIXES is that the multitude of diverse environmental niches of the Mediterranean Sea contains a huge range of microorganisms and their components (e.g. catabolic enzymes) or products (e.g. biosurfactant) that can be exploited in pollutant- and site-tailored bioremediation approaches. ULIXES intends to provide the proof of concept that it is possible to establish and exploit for bioremediation site-specific collections of microbial strains, mixed microbial cultures, enzymes, biosurfactants and other microbial products. These biotechnological resources will be mined by using approaches based on isolation of culturable microorganisms as well as by extensively applying advanced novel meta-omics technologies recently developed by the project partners and exclusively available for ULIXES. Three pollutant classes recognized worldwide as environmental priorities will be considered: petroleum hydrocarbons, chlorinated compounds and heavy metals. A large set of polluted environmental matrices from sites located all over the Mediterranean Sea will be explored, including seashore sands, lagoon sediments, deep sea sediments polluted by heavy oil hydrocarbons at oil tanker shipwreck sites, hypersaline waters and sediments from polluted salty coastal lakes and natural deep hypersaline anoxic submarine basins and mud volcanoes where hydrocarbon seepages occur. The mined collections of microbial biotechnological products will be exploited for development of novel improved bioremediation processes whose effectiveness will be proved by ex situ and in situ field bioremediation trials. A careful dissemination action will be pursued to assure capillary information of the ULIXES results and products to stakeholders and SMEs operating in the sector of marine bioremediation.
Al-Agtash S.Y.,Yarmouk University
Energy | Year: 2010
This paper presents a Supply Curve Bidding (SCB) approach that complies with the notion of the Standard Market Design (SMD) in electricity markets. The approach considers the demand-side option and Locational Marginal Pricing (LMP) clearing. It iteratively alters Supply Function Equilibria (SFE) model solutions, then choosing the best bid based on market-clearing LMP and network conditions. It has been argued that SCB better benefits suppliers compared to fixed quantity-price bids. It provides more flexibility and better opportunity to achieving profitable outcomes over a range of demands. In addition, SCB fits two important criteria: simplifies evaluating electricity derivatives and captures smooth marginal cost characteristics that reflect actual production costs. The simultaneous inclusion of physical unit constraints and transmission security constraints will assure a feasible solution. An IEEE 24-bus system is used to illustrate perturbations of SCB in constrained power networks within the framework of SDM. By searching in the neighborhood of SFE model solutions, suppliers can obtain their best bid offers based on market-clearing LMP and network conditions. In this case, electricity producers can derive their best offering strategy both in the power exchange and the long-term contractual markets within a profitable, yet secure electricity market. © 2010 Elsevier Ltd.
Alomoush M.I.,Yarmouk University
Electrical Engineering | Year: 2010
Recently, fractional calculus has received extensive attention and research. Accordingly, there is an increasing interest in fractional-order (FO) dynamic systems and controllers. The widely used classical integer-order proportional-integral controller and proportional-integral-derivative controller are usually adopted in the load frequency control (LFC) and automatic generation control (AGC) to improve the dynamic response and to eliminate or reduce steady-state errors. This paper utilizes the FO controllers to improve stability and response of LFC and AGC system. The paper uses the integral of the time-weighted absolute error performance index for optimal controller design. The paper investigates LFC and AGC for both isolated and interconnected power systems and shows that FO controllers perform better than classical integer-order controllers in theses systems. © Springer-Verlag 2009.
Alomary A.,Yarmouk University
Environmental Monitoring and Assessment | Year: 2013
Drinking water samples from Irbid, the second populated city in Jordan were analyzed for trace metals (As, Ba, Cd, Pb, Cr, Cu, Fe, Zn, Mn, Ni, and Se) content. The study was undertaken to determine if the metal concentrations were within the national and international guidelines. A total of 90 drinking water samples were collected from Al-Yarmouk University area. The samples were collected from three different water types: tap water (TW), home-purified water (HPW), and plant-purified water (PPW). All the samples were analyzed for trace metals using an inductively coupled plasma-optical emission spectrometry. All the samples analyzed were within the United States Environmental Protection Agency admissible pH limit (6.5-8.5). The results showed that concentrations of the trace metals vary significantly between the three drinking water types. The results showed that HPW samples have the lowest level of trace metals and the concentrations of some essential trace metals in these samples are less than the recommended amounts. Slight differences in the metal contents were found between HPW samples, little differences between PPW samples; however, significant differences were found between TW samples. Although some TW samples showed high levels of trace metals, however, the mean level of most elements determined in the samples were well within the Jordanian standards as well as the World Health Organization standards for drinking water. © 2012 Springer Science+Business Media B.V.
Bany Salameh H.A.,Yarmouk University
Mathematical and Computer Modelling | Year: 2011
Cognitive radio (CR) is a revolutionary technology in wireless communications that enhances spectrum utilization by allowing opportunistic and dynamic spectrum access. One of the key challenges in this domain is how CR users cooperate to dynamically access the available spectrum opportunities in order to maximize the overall perceived throughput. In this paper, we consider the coordinated spectrum access problem in a multi-user single-transceiver CR network (CRN), where each CR user is equipped with only one half-duplex transceiver. We first formulate the dynamic spectrum access as a rate/power control and channel assignment optimization problem. Our objective is to maximize the sum-rate achieved by all contending CR users over all available spectrum opportunities under interference and hardware constraints. We first show that this problem can be formulated as a mixed integer nonlinear programming (MINLP) problem that is NP-hard, in general. By exploiting the fact that actual communication systems have a finite number of available channels, each with a given maximum transmission power, we transfer this MINLP into a binary linear programming problem (BLP). Due to its integrality nature, this BLP is expected to be NP-hard. However, we show that its constraint matrix satisfies the total unimodularity property, and hence our problem can be optimally solved in polynomial time using linear programming (LP). To execute the optimal assignment in a distributed manner, we then present a distributed CSMA/CA-based random access mechanism for CRNs. We compare the performance of our proposed mechanism with reference CSMA/CA channel access mechanisms designed for CRNs. Simulation results show that our proposed mechanism significantly improves the overall network throughput and preserves fairness. © 2010 Elsevier Ltd.
Halloush M.,Yarmouk University |
Radha H.,Michigan State University
IEEE Transactions on Wireless Communications | Year: 2011
Due to the broadcast nature of wireless networks they have been a natural platform for applying Network Coding (NC). Wireless networks can benefit significantly from NC due to their broadcast nature and the opportunity of enhancing bandwidth utilization. In this paper, we develop Multi-Generation Mixing (MGM), which is a generalized approach for generation based network coding. With traditional generation based NC sender packets are grouped in generations where encoding and decoding are performed on packets that belong to the same generation. In scenarios where losses cause insufficient reception of encoded packets, NC losses occur. NC losses are expensive; the minimum unit of loss is the loss of one generation. The proposed MGM framework allows the encoding among generations for the purpose of enhancing NC decodability. With MGM in scenarios where insufficient number of encodings received of a generation, it is still possible to recover the generation using data encoded in other generations. We develop MGM encoding and decoding approaches, and demonstrate the improvements in performance achieved by MGM. Further, a canonical analytical model for MGM network coding is developed, and, extensive simulations over random wireless networks experiencing random packet losses are presented. © 2011 IEEE.
Shatnawi Y.,Yarmouk University |
Al-Khassaweneh M.,Yarmouk University
IEEE Transactions on Industrial Electronics | Year: 2014
The internal combustion engine (ICE) is a special type of reciprocating and rotating machine which is an essential part of every automobile and industry in our modern life. Various faults frequently encounter this machine and cause significant losses. Thus, in this paper, we propose an effective and automated technique to diagnose the faults. Unlike the existing methods in this field, the emitted sound signal of the 'ICE' is exploited as the information carrier of the faults, wavelet packet decomposition is used as the feature extraction tool, and finally, extension artificial neural network is used for the classifications of the extracted features. The extension neural network (ENN) consists of just the input layer and the output layer. This simple structure of the 'ENN' enhances the performance compared to the traditional neural networks and enables us to easily insert any new information, like a new fault or new feature. Therefore, 'ENN' is adaptive for new information by just adding new nodes without affecting the previously built network. The results of the proposed method show the effectiveness and the high recognition rate in classifying different faults. © 1982-2012 IEEE.
Migdadi Y.K.A.-A.,Yarmouk University
International Journal of Services and Operations Management | Year: 2012
The aim of this study is to identify the effective banking service delivery process design strategy during the period 1999 to 2008. Fifteen local banks in Jordan were surveyed by using three questionnaires, one of them directed to branch managers, another to tellers and last one to front office credit employees. This study revealed that the majority of process design actions made were related to information system, however, the significant capabilities were related to reducing account transaction time, reducing account transaction cost, improving tellers' productivity, reducing loan approval time, and reducing loan approval cost. The relative impact of information system actions on account transaction time and loan approval time is significantly more than reducing number of process steps. The banks in Jordan and other developing countries can focus now on more effective aspects of process design rather than investing in less effective actions. No previous study reported in-depth the banking service delivery process, so this paper is the first paper that reports this issue in developing economies. Copyright © 2012 Inderscience Enterprises Ltd.
Al-Taani A.A.,Yarmouk University
Arabian Journal of Geosciences | Year: 2013
Al-Wehda dam is an impoundment on the Yarmouk River basin north of Jordan, which came recently into operation. The reservoir is designated to provide water for agricultural, domestic, and industrial uses. Evaluation of seasonal trends in water quality of Al-Wehda dam over the year 2010 showed strong influences by weathering and leaching of geologic units along with discharge of effluents from the adjacent agricultural lands. Seasonal trends in TDS level showed slight variations, though its concentrations have been affected by events of rainfall and evaporation. The presence of total nitrogen (TN) and total phosphorus (TP) promoted the development of photosynthetic algae. Temporal fluctuations in TN, TP, chlorophyll a, COD, and BOD have been observed with peaks occurred in spring season. TN to TP ratios varied seasonally with a minimum ratio observed in spring concurrent with algal bloom. Eutrophication tends to occur throughout the year, though its intensity increased in springtime. A variety of water quality parameters has been used to evaluate water for irrigation use during summer time when the water demand for irrigation increased. Of all parameters evaluated, Na% and TH indicated that the reservoir water is not suitable for irrigation purposes. © 2011 Saudi Society for Geosciences.