bluuebunny/crossref_metadata_2025 huggingface dataset:
Intelligent Well Completion in the Kitan Oil Field
Authors: Yokote Ryosuke , Milne John , Sanasi Carla , Hosatte Pierre , Mukashev Nurtas , Chadha Nishant
Published: October 2012

The first hydraulically operated completion was installed in Australia in 2004 (Guatelli et al 2004). Since then, a number of intelligent completions have been installed in offshore Australia. The remoteness of offshore Australia, particularly in the Timor Sea area, means intervention vessels are not readily available and well interventions are costly operations. For this reason, intelligent completion is considered to be an attractive alternative, by providing a down-hole solution to actively manage the reservoir production life and delay potential water breakthrough.

The Kitan oil field is remotely located in the Joint Petroleum Development Area (JPDA) between East Timor and Australia. The Kitan oil field production facilities consist of three vertical producing wells, subsea flowlines, risers, and one Floating Production Storage and Offloading (FPSO) facility. The wells were completed with an intelligent design and cleaned up using a rig before the FPSO arrived on location.

The intelligent completion design consists of two multi-stage hydraulic down-hole Flow Control Valves (FCVs) and three Down-Hole Gauges (DHGs) to independently control and monitor two different production zones. The FCVs have a total of 8 positions (fully opened, fully closed and 6 intermediate choke positions).

It is planned to close the lower FCV to shut off water production from the lower zone while the upper FCV remains fully opened over the field life. The different FCV choke positions were utilized during the field startup and during the early stages of production while the water cut was still low, to overcome unforeseen technical limitations in the production system, and to optimize hydrocarbon production.

This paper describes various aspects of the Kitan oil field intelligent well completion from design through installation and field startup to early stage of production operations, and includes technical problems encountered during the field startup as well as lessons learnt.
Reservoir Fluid Characterization for Tight Fractured Reservoirs: Effect of Diffusion
Authors: Imai Motonao , Sumikawa Isami , Yamada Tomomi , Nakano Masanori
Published: October 2012

Molecular diffusion effect has been ignored in many conventional reservoir studies, but it can play a significant role in tight fractured reservoirs and is crucial for an appropriate reservoir evaluation. We have characterized diffusion coefficients of methane gas in hydrocarbon fluid samples by combining experiment and simulation.

We employ the theory of Fickian diffusive flux to evaluate molecular diffusion behavior. It is described as a product of concentration gradient, molar density and Fickian diffusion coefficient. Diffusion coefficients, although commonly estimated by existing correlations, shall be calibrated against actual molecular diffusion behavior for practical use. There have been few published papers showing Fickian multicomponent diffusion coefficients, because a simple and reliable measurement method has not been available. We hereby propose a method for computer-assisted multicomponent diffusion coefficient evaluation based on experiments proposed by Riazi that uses a PVT cell apparatus.

We measure molecular diffusion behavior in a PVT cell and evaluate diffusion coefficients using Leahy-Dios and Firoozabadi's model with the assumption of local equilibrium described by the Peng-Robinson EOS. Volume shift parameters, binary interaction coefficients, initial pressure, initial liquid volume and diffusion coefficients are optimized to fit measurements by a new global optimization algorithm named iterative Latin hypercube samplings.

Simulation case studies are performed to show the effect of molecular diffusion in tight fractured reservoirs. Results indicate that injected gas diffuses deeply into rock matrices when diffusive flux is properly represented. Consequently, better sweep efficiency is achieved compared to the cases without considering diffusion.

In this paper, we present a systematic method to evaluate diffusion coefficients of reservoir fluids using EOS. It will be useful for reservoir simulation of oil and gas recovery in tight fractured reservoirs.
Harmonic Vibration Disruption Improves Drilling Performance in Challenging Applications
Authors: Bouziane Chakib , Bates Paul , May Norman , Nicholl Denise , Burnett Timm , Minardi Andrea , Golin Mario , BenMohamed Mohamed Heidi , Bennati Simone , Angeletti Paolo
Published: October 2012

The majority of wells drilled in Algeria are vertical with three hole sections 16, 12¼ and 8½ inches. The main challenge in these applications is the ability to manage the drilling system for optimal performance by drilling efficiently minimizing both drill string component and well bore damage. The highly interbedded and variable compressive strength of the formations make the system prone to severe vibrations.

Vibrations are generated down hole while drilling. There are three types of vibration modes and they follow in order of severity, axial, torsional, and lateral. Lateral vibration is the most destructive mode and can create large shocks down hole with the Bottom Hole Assembly (BHA) components impacting the wellbore wall. The design of the drilling system should maximize the transfer of all the energy put into the drilling system drilling the hole rather than vibration. The anti-vibration sub is a tool designed to benefit the drilling by mitigating lateral vibration as part of the required energy management for efficient drilling. This has been observed through downhole data as well as Mechanical Specific Energy (MSE) comparisons.

Unlike traditional stabilizers, the near bit anti-vibration stabilizer acts more like a stabilizer and a centralizer while not generating point loaded blade friction associated with traditional stabilizers. The system has been introduced successfully on rotary BHAs with all types of drill bits. The cost per meter has been reduced while improving borehole quality thus reducing associated non-productive time required when conditioning the hole prior to setting casing.

This paper presents the field data acquired which indicates the importance of choosing the correct type, dimensions, and placements of the anti-vibration stabilizer. This anti-vibration stabilizer has been successfully utilized in several applications and is currently standard equipment for most vertical wells with rotary BHAs in Algeria.
Carbon footprint and life cycle assessment of centralised and decentralised handling of wastewater during rain
Authors: Clauson-Kaas Jes , Sørensen Birgitte Lilholt , Dalgaard Ole G. , Sharma Anitha K. , Johansen Niels Bent , Rindel Kim , Andersen Helle K.
Published: October 2012

The most widely used approaches for handling of combined sewer overflows (CSOs) are: (1) storage in smaller retention basins and local decentralised treatment; and (2) storage in larger retention basins and treatment at a central wastewater treatment plant. This paper compares the environmental impact including carbon footprint for these two approaches using the life cycle assessment (LCA) method, and provides a holistic view of how CSO is to be treated considering technical, economic and environmental issues. The analysis is based on the results of the EU-financed LotWater project and 9 years of operational data from wastewater treatment in Copenhagen. All technologies are analysed for handling of 1 m3 of CSO. However, costs are compared based on cost per reduced area. The study showed that decentralised treatment of CSO is the cheapest method and the power consumption for the decentralised treatment is five times less than that for central treatment of CSO. However, central treatment of CSO appeared to be most efficient in reducing discharge of nutrients and environmental toxics. The LCA showed that the largest environmental impacts from handling CSOs are eutrophication and aquatic ecotoxicity. This study concludes that focusing on global warming alone in the form of reduced energy consumption could result in negative impacts on recipient waters.
Implications of climate and urban development on the design of sustainable urban drainage systems (SUDS)
Authors: Semadeni-Davies Annette
Published: October 2012

This paper explores the implications of climate change and urban development on the design of sustainable urban drainage systems (SUDS) using the example of ponds and raingardens in Auckland, New Zealand. Many of Auckland's coastal and freshwater receiving environments have been degraded due to stormwater inflows and are potentially at further risk due to continued urbanisation and climate change. SUDS have been suggested as a possible means of adapting to those risks. However, there is little guidance available on how they should be designed for future conditions. Response-curves which relate changes in SUDS sizing to both climate change and imperviousness are presented as a means of displaying a range of possible future design needs. It is suggested that they could aid in the selection of adaptation strategies. The methodology followed is based on publicly available guidance material to provide a real world example of the design issues facing stormwater managers. An incremental adaptation strategy, whereby construction is staggered over time, is recommended for ponds which vary greatly in size depending on the projected climate and imperviousness. In contrast, adapting raingardens at the time of construction is pragmatic as the change in size, with even the maximum projected climate change, is modest.
A Summary of Research on External Auditor Reliance on the Internal Audit Function
Authors: Bame-Aldred Charles W. , Brandon Duane M. , Messier William F. , Rittenberg Larry E. , Stefaniak Chad M.
Published: October 2012

Public Company Accounting Oversight Board (PCAOB) Auditing Standard No. 5 (AS5) allows external auditors (EAs) to rely on the internal audit function (IAF) when the internal audit activities meet certain criteria and the EAs would find efficiencies in relying on their work (PCAOB 2007). This paper reviews the extant literature on the EAs' reliance on IAF, identifies gaps in the literature, and proposes a series of research questions aimed at closing these gaps. We focus our review on research pertaining to how environmental factors and IAF-specific factors influence initial EAs' reliance decisions, the nature and extent of EAs' reliance on IAF, and the observable outcomes as a result of EAs' reliance decisions. Our review finds that the environment in which EAs must make a reliance decision is complex—involving several factors that must be considered simultaneously. Moreover, an evolving set of auditing standards introduces several necessary intermediary judgments that the EAs must process before, and during, reliance on the IAF. In addition, our review indicates that we continue to know very little about how, and to what extent, EAs are currently evaluating IAF's quality factors. Similarly, while we find that the nature and extent of EAs' reliance on IAF is influenced by account risk, inherent risk, and IAF sourcing, how the EAs choose task environments (e.g., revenue recognition versus payroll), and the types of tests to be relied upon within these task environments, is not completely understood. Finally, we find that there is a paucity of research concerning the effects of EAs' reliance on IAF in terms of external audit quality.
Labeled vs Actual Concentration of Bleaching Agents
Authors: Matis BA , Matis JI , Wang Y , Monteiro S , Al-Qunaian TA , Millard R
Published: October 2012

The purpose of this study was to determine if the actual concentration of bleaching agents available in four different countries were the same as the label indicated and within the recommendations of the International Standard on Tooth Whitening. The method recommended for assaying peroxide by the United States Pharmacopeia was used to determine concentrations. All products in the United States and China were within the standard when products were tested immediately upon delivery at testing sites. One product in Saudi Arabia and three products in Brazil had greater than 30% concentration loss. Three of 24 products in the United States did not meet the International Standard when they were tested at month of expiration.
Comparison of Acid Versus Laser Etching on the Clinical Performance of a Fissure Sealant: 24-Month Results
Authors: Karaman E , Yazici AR , Baseren M , Gorucu J
Published: October 2012

Objective

To compare the clinical performance of a pit and fissure sealant placed with the use of different enamel preparation methods, i.e. acid or Er,Cr:YSGG laser etching, over 24 months.

Methods

Sixteen subjects (15 female, 1 male) with no restorations or sealant present on their fissures and no detectable caries participated. Using a table of random numbers, a total of 112 sealants (56 with acid-etching, 56 with laser etching) were placed on the permanent premolar and molar teeth. All restorative procedures except for application of the laser were performed by the same dentist. After completion of the fissure preparation either with acid or laser, the adhesive was applied; then a pit and fissure sealant, Clinpro Sealant, was placed and polymerized. Clinical evaluations were done at baseline and at 6-, 12-, 18-, and 24-month follow-up visits by two calibrated examiners, who were unaware of which etching method had been used. The retention of sealants and caries were evaluated with the aid of a dental explorer and an intra-oral mirror. Each sealant was evaluated using the following criteria: 1=completely retained; 2= partial loss; 3= total loss. The Pearson chi-square test was used to evaluate differences in the retention rates among the sealants used with different etching methods.

Results

All patients attended the 24-month follow-up visit and all sealants were evaluated (total recall rate 100%). At the end of 24 months, 83.9% of the sealants from laser group and 85.7% of those from acid-etch group were recorded as “completely retained”. There were no statistically significant differences in retention rates among the preparation methods after all evaluation periods (p>0.05). No statistically significant differences were found between the retention rates of premolar and molars at each evaluation period. No secondary caries was detected in association with any sealants. Conclusion: The clinical performance of fissure sealants placed after acid or Er,Cr:YSGG laser etching was similar.
The Vented Crown: A Pictorial Case Report
Authors: Small B
Published: October 2012

The venting of crowns has been shown to be one of the important factors in achieving the optimal marginal fit that can lead to improved longevity. This case report describes the technique and demonstrates the preparation, laboratory work, seating, and finishing of the vented cast gold crown. This technique can also be used on porcelain fused to metal crowns.
Clinical Effectiveness of a Hydrophobic Coating Used in Conjunction With a One-step Self-etch Adhesive: An 18-month Evaluation
Authors: Sartori N , Peruchi LD , Guimarães JC , Silva SB , Monteiro S , Baratieri LN , Belli R
Published: October 2012

The purpose of this randomized clinical trial was to evaluate the clinical performance of a one-step self-etch adhesive in noncarious cervical lesions with inclusion of a hydrophobic bonding layer not included in the original bonding system as a test of potentially improved bonding. Patients with noncarious cervical lesions received two or four restorations after being randomly assigned to two adhesive technique protocols (n=32): EB, application of Adper Easy Bond (3M ESPE) following manufacturer's instructions; and EB+B, application of Adper Easy Bond, immediately followed by the application of a hydrophobic resin coat (Scotchbond Multi-Purpose Bonding Agent, 3M ESPE). All restorations were restored with a microhybrid composite (Filtek Z250, 3M ESPE). Clinical effectiveness was recorded in terms of retention, marginal discoloration, marginal integrity, postoperative sensitivity, recurrent caries, periodontal health, and pulpal vitality, according to the modified USPHS criteria, for 18 months. Data were analyzed using chi-square, Fisher exact, and McNemar tests at α=0.05. Two restorations of each group were debonded after six months, leading to an overall clinical success rate of 93.8% for both groups. At the 18-month evaluation period, no new restoration was debonded. However, one restoration of the EB group displayed recurrent caries at the dentin margin, decreasing the overall success rate to 90.6% in comparison to 93.8% of EB+B. The success rate between EB and EB+B was not statistically significant (p=0.5). The application of a hydrophobic resin coat over EB did not increase bonding effectiveness in noncarious cervical lesions after 18 months.
Potassium trans-[bis(oxalato)diaquacobaltate(II)] tetrahydrate: synthesis, structure, potentiometric and thermal studies
Authors: Chylewska Agnieszka , Sikorski Artur , Dąbrowska Aleksandra , Chmurzyński Lech
Published: October 2012

The title compound, trans-K2[Co(C2O4)2(H2O)2]·4H2O, was synthesised, and characterised by elemental analysis. Acid dissociation constants for the complex were determined by potentiometric titration and calculated by STOICHIO program. The crystal structure of trans-K2[Co(C2O4)2(H2O)2]·4H2O was determined by X-ray diffraction studies. The asymmetric part of the unit cell contains one symmetric anion of oxalate and water molecule bound with Co(II) ion in crystallographic special position, one potassium cation and two molecules of water. Thermal properties of the complex were examined by thermogravimetric analysis (TGA). A decomposition mechanism is proposed on the basis of the results.
A close analysis of metal-enhanced fluorescence of tryptophan induced by silver nanoparticles: wavelength emission dependence
Authors: Caires Anderson , Costa Luciano , Fernandes Joelson
Published: October 2012

In the last few years, silver nanoparticles have been proposed as a promising alternative for the label-free detection of proteins via metal-enhanced fluorescence. Generally, the aromatic amino acid tryptophan is most frequently used in this type of studies, because the intrinsic fluorescence of proteins is usually dominated by tryptophan emissions. In the present study, we evaluated the fluorescence behavior of tryptophan in the presence of a silver colloid with nanoparticles of 100 nm in diameter. The results showed that a nanoparticles concentration of 32 mg L−1 induced maximum fluorescence enhancement. However, the metal-enhanced fluorescence was dependent on the emission wavelength of tryptophan, and this phenomenon was closely related to the metal surface reabsorption process (inner filter effect), suggesting that the plasmon resonance reabsorption effect should be taken into account in analyses involving protein studies by metal-enhanced fluorescence.
Medical Quiz : SBA
Authors: Editor The
Published: October 2012

(Birdem Med J 2012; 2(2): 131)
Some Epidemiological Aspects Of Subfertile Women Who Underwent Laparoscopy
Authors: Deeba Farzana , Alam ABM Muksudul , Ava Nilufar Nasrin , Islam Md. Rafiqul , Matin Abdul , Khan Rita
Published: October 2012

Objective: Epidemiological aspects of sitbfertile women underwent laparoscopy. Place of Study: This retrospective study was done in the Obstetrics and Gynaecology Department of Bangladesh Medical College hospital. Duration: July 2003 to June 2004. Study Population: Women suffering from primarv and secondary subfertility, who had under gone laparoscopy. Total 61 patient had laparoscopy for evaluation of subfertility. No documents were available for 6 patient and they were excluded from the study. Result: The study group comprises 55 cases of which 67.37% was of primary and 32. 73", was of secondary subfertility. Professional women group (56.4%) was higher than housewife group (43.6%). In this study 11.11% had history of spontaneous abortion and 33.33% had history of MR. In this study menstrual period was within 7 days in 70.9% cases and in 10.9% cases were more than 7 days, in 14.54% cases menstrual cycle was more than 35 days and in 3.64% cases were less than 22 days. 40% of the patient did not used any contraceptive. Conclusion: The number of subfertility visits' has increased in the last few rears because of increasing awareness for available services and option for resolving subfertilitv. Prompt investigation and appropriate referral allow a couple to receive advice and treatment to help them reach their goal. Journal of Shaheed Suhrawardy Medical College Vol 2No.1 June 2010 page 6-9 DOI: http://dx.doi.org/10.3329/jssmc.v2i1.12343
Infant Feeding Practices Among Mothers Of High And Low Socio-Economic Group In Selected Areas of Dhaka City
Authors: Khatun Momena , Siddiqua Shireen Ayesha
Published: October 2012

Objectives: To study the patterns of infant feeding practice among the mothers of high and low socio-economic groups.Design: The descriptive cross-sectional study was conducted among a cross section of mothers with infant of high socioeconomic group, the residents of Sobhanbag government colony & Panthopath Green road residential area and low socioeconomic group slum area of Raver bazar, Dhaka. The study was carried out during the period of October '2007 to May '2008. Results: Total 104 children, 41.3% were in 9 months or more age and of them 40.3% were in high socioeconomic group & 42.3% were in low socioeconomic group. About 96.2% mothers from high socio-economic group provide either fullv or partiallv correct answer to the question regarding the benefit of colostrums and 59.7% from low-socio-economic group. Again, among the mothers from high socioeconomic groups 90.4% and 61.5% stated fully or partiallv correct answer about the benefits of breast feeding & the optimum weaning time respectively. Colostrums intake practice was observed 94.2% mothers of high socio-economic group and 67.3% of low of socioeconomic group. Breast milk as the first food to their babies was given 71.2% mothers of high & 65.4% of low socioeconomic group. The rate of exclusive breast feeding among mothers of 2-3 months baby from high socio-economic group was found 41.2% and low socio-economic group 34.4%. Conclusion: From this study it was evident that mothers of low socioeconomic group have poor knowledge regarding the infant feeding practices. So, Breast feeding campaign should he directed to the low socioeconomic group bv more effective wav. Strengthening of breast-feeding counseling at primarv health care center in both rural and urban area can play significant role in this regard. Journal of Shaheed Suhrawardy Medical College Vol 2No.1 June 2010 page 17-21 DOI: http://dx.doi.org/10.3329/jssmc.v2i1.12346
Short Term Electric Production Technology Switching Under Carbon Cap and Trade
Authors: Considine Timothy , Larson Donald F.
Published: October 2012

This study examines fuel switching in electricity production following the introduction of the European Union’s Emissions Trading System (EU ETS) for greenhouse gas emissions. A short-run restricted cost equation is estimated with carbon permits, high-carbon fuels, and low carbon fuels as variable inputs. Shadow values and substitution elasticities for carbon-free energy resources from nuclear, hydroelectric and renewable sources are imputed from the cost equation. The empirical analysis examines 12 European countries using monthly data on fuel use, prices, and electricity generation during the first phase of the European Emissions Trading System. Despite low emission permit prices, this study finds statistically significant substitution between fossil fuels and carbon free sources of energy for electric power production. Significant substitution between fossil fuels and nuclear energy also was found. Still, while 18 of the 20 substitution elasticities are statistically significant, they are all less than unity, consistent with limited substitution. Overall, these results suggest that prices for carbon emission permits relative to prices for carbon and carbon free sources of energy do matter but that electric power producers have limited operational flexibility in the short-run to satisfy greenhouse gas emission limits.
Parabolic Trough Photovoltaic/Thermal Collectors: Design and Simulation Model
Authors: Calise Francesco , Vanoli Laura
Published: October 2012

This paper presents a design procedure and a simulation model of a novel concentrating PVT collector. The layout of the PVT system under investigation was derived from a prototype recently presented in literature and commercially available. The prototype consisted in a parabolic trough concentrator and a linear triangular receiver. In that prototype, the bottom surfaces of the receiver are equipped with mono-crystalline silicon cells whereas the top surface is covered by an absorbing surface. The aperture area of the parabola was covered by a glass in order to improve the thermal efficiency of the system. In the modified version of the collector considered in this paper, two changes are implemented: the cover glass was eliminated and the mono-crystalline silicon cells were replaced by triple-junction cells. In order to analyze PVT performance, a detailed mathematical model was implemented. This model is based on zero-dimensional energy balances. The simulation model calculates the temperatures of the main components of the system and the main energy flows Results showed that the performance of the system is excellent even when the fluid temperature is very high (>100 °C). Conversely, both electrical and thermal efficiencies dramatically decrease when the incident beam radiation decreases.
A Review on Waste to Energy Processes Using Microwave Pyrolysis
Authors: Lam Su Shiung , Chase Howard A.
Published: October 2012

This paper presents an extensive review of the scientific literature associated with various microwave pyrolysis applications in waste to energy engineering. It was established that microwave-heated pyrolysis processes offer a number of advantages over other processes that use traditional thermal heat sources. In particular, microwave-heated processes show a distinct advantage in providing rapid and energy-efficient heating compared to conventional technologies, and thus facilitating increased production rates. It can also be established that the pyrolysis process offers an exciting way to recover both the energetic and chemical value of the waste materials by generating potentially useful pyrolysis products suitable for future reuse. Furthermore, this review has revealed good performance of the microwave pyrolysis process when compared to other more conventional methods of operation, indicating that it shows exceptional promise as a means for energy recovery from waste materials. Nonetheless, it was revealed that many important characteristics of the microwave pyrolysis process have yet to be raised or fully investigated. In addition, limited information is available concerning the characteristics of the microwave pyrolysis of waste materials. It was thus concluded that more work is needed to extend existing understanding of these aspects in order to develop improvements to the process to transform it into a commercially viable route to recover energy from waste materials in an environmentally sustainable manner.
Creating Open Government Ecosystems: A Research and Development Agenda
Authors: Harrison Teresa M. , Pardo Theresa A. , Cook Meghan
Published: October 2012

In this paper, we propose to view the concept of open government from the perspective of an ecosystem, a metaphor often used by policy makers, scholars, and technology gurus to convey a sense of the interdependent social systems of actors, organizations, material infrastructures, and symbolic resources that can be created in technology-enabled, information-intensive social systems. We use the concept of an ecosystem to provide a framework for considering the outcomes of a workshop organized to generate a research and development agenda for open government. The agenda was produced in discussions among participants from the government (at the federal, state, and local levels), academic and civil sector communities at the Center for Technology in Government (CTG) at the University at Albany, SUNY in April 2011. The paper begins by discussing concepts central to understanding what is meant by an ecosystem and some principles that characterize its functioning. We then apply this metaphor more directly to government, proposing that policymakers engage in strategic ecosystems thinking, which means being guided by the goal of explicitly and purposefully constructing open government ecosystems. From there, we present the research agenda questions essential to the development of this new view of government's interaction with users and organizations. Our goal is to call attention to some of the fundamental ways in which government must change in order to evolve from outdated industrial bureaucratic forms to information age networked and interdependent systems.
Modeling Inequity Aversion in a Dictator Game with Production
Authors: Rodriguez-Lara Ismael , Moreno-Garrido Luis
Published: October 2012

We expand upon the previous models of inequity aversion of Fehr and Schmidt [1], and Frohlich et al. [2], which assume that dictators get disutility if the final allocation of surplus deviates from the equal split (egalitarian principle) or from the subjects' production (libertarian principle). In our model, dictators may also account for the way in which the surplus was generated. More precisely, our model incorporates the idea of liberal egalitarian ethics into the analysis, making it possible for dictators to divide the surplus according to the accountability principle, which states that subjects should only be rewarded for factors under their control. This fairness ideal does not hold subjects responsible for factors beyond their control in the production of the surplus, an idea that is absent in the models of inequity aversion cited above (JEL Codes: D3, D6, D63).
Correction: Lwanga, F., et al. Intestinal Helminth Infections and Nutritional Status of Children Attending Primary Schools in Wakiso District, Central Uganda. Int. J. Environ. Res. Public Health 2012, 9, 2910-2921
Authors: Lwanga Francis , Kirunda Barbara Eva , Orach Christopher Garimoi
Published: October 2012

The author wish to make the following correction to this paper [1]: The author name “Lwanga Francis” should be “Francis Lwanga”.
The Criteria to Confirm the Role of Epstein-Barr Virus in Nasopharyngeal Carcinoma Initiation
Authors: Gu Ai-Di , Zeng Mu-Sheng , Qian Chao-Nan
Published: October 2012

Epstein-Barr virus (EBV) is associated with nasopharyngeal carcinoma (NPC), but it remains obscure whether EBV is a viral cause of, or only an accompaniment of, NPC. We will discuss the accumulated evidence pointing to the relationship between EBV infection and NPC initiation from epidemiologic, pathogenic, molecular oncogenic, and experimental animal studies. We believe that convincing evidence from these perspectives must be provided before we can ascertain the causal role of EBV infection in NPC. Specifically, (1) epidemiological studies should reveal EBV infection as a risk factor; (2) the introduction of EBV into an animal model should produce NPC; (3) in the animal model NPC, the main molecular event(s) or the involved signaling pathway(s) should be identical to that in human NPC; and (4) finally and most importantly, prevention of EBV infection or clearance of EBV from infected individuals must be able to reduce the incidence rate of NPC.
Power Scalable Radio Receiver Design Based on Signal and Interference Condition
Authors: Dwivedi Satyam , Amrutur Bharadwaj , Bhat Navakanta
Published: October 2012

A low power adaptive digital baseband architecture is presented for a low-IF receiver of IEEE 802.15.4-2006. The digital section’s sampling frequency and bit width are used as knobs to reduce the power under favorable signal and interference scenarios, thus recovering the design margins introduced to handle the worst case conditions. We show that in a 0.13 μm CMOS technology, for an adaptive digital baseband section of the receiver, power saving can be up to 85% (0.49mW against 3.3mW) in favorable interference and signal conditions. The proposed concepts in the design are tested using a receiver test setup where the design is hosted on a FPGA.
Solvent Composition is Critical for Carbodiimide Cross-Linking of Hyaluronic Acid as an Ophthalmic Biomaterial
Authors: Lai Jui-Yang
Published: October 2012

Hyaluronic acid (HA) is one of the most important ophthalmic biomaterials, while also being used for tissue engineering and drug delivery. Although chemical cross-linking is an effective way to improve the material performance, it may as a consequence be detrimental to the living cells/tissues. Given that the cross-linking efficiency is mediated by the solvent composition during the chemical modification, this study aims to explore the stability and biocompatibility of carbodiimide cross-linked HA in relation to material processing conditions by varying the acetone/water volume ratio (from 70:30 to 95:5) at a constant 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) concentration of 100 mM. Our results indicated that after the EDC treatment in the presence of an acetone/water mixture (85:15, v/v), the HA hydrogel membranes have the lowest equilibrium water content, the highest stress at break and the greatest resistance to hyaluronidase digestion. Live/Dead assays and pro-inflammatory cytokine expression analyses showed that the cross-linked HA hydrogel membranes, irrespective of the solvent composition, are compatible with human RPE cell lines without causing toxicity and inflammation. However, it should be noted that the test samples prepared by the cross-linking in the presence of acetone/water mixtures containing 70, 75, and 95 vol % of acetone slightly inhibit the metabolic activity of viable ARPE-19 cultures, probably due to the alteration in the ionic interaction between the medium nutrients and polysaccharide biomaterials. In summary, the water content, mechanical strength and RPE cell proliferative capacity strongly depends on the solvent composition for carbodiimide cross-linking of HA materials.
Investigation of Iron Oxide Morphology in a Cyclic Redox Water Splitting Process for Hydrogen Generation
Authors: Bobek Michael M. , Stehle Richard C. , Hahn David W.
Published: October 2012

A solar fuels generation research program is focused on hydrogen production by means of reactive metal water splitting in a cyclic iron-based redox process. Iron-based oxides are explored as an intermediary reactive material to dissociate water molecules at significantly reduced thermal energies. With a goal of studying the resulting oxide chemistry and morphology, chemical assistance via CO is used to complete the redox cycle. In order to exploit the unique characteristics of highly reactive materials at the solar reactor scale, a monolithic laboratory scale reactor has been designed to explore the redox cycle at temperatures ranging from 675 to 875 K. Using high resolution scanning electron microscope (SEM) and electron dispersive X-ray spectroscopy (EDS), the oxide morphology and the oxide state are quantified, including spatial distributions. These images show the change of the oxide layers directly after oxidation and after reduction. The findings show a significant non-stoichiometric O/Fe gradient in the atomic ratio following oxidation, which is consistent with a previous kinetics model, and a relatively constant, non-stoichiometric O/Fe atomic ratio following reduction.
Advances in Drug Design Based on the Amino Acid Approach: Taurine Analogues for the Treatment of CNS Diseases
Authors: Chung Man Chin , Malatesta Pedro , Bosquesi Priscila Longhin , Yamasaki Paulo Renato , Santos Jean Leandro dos , Vizioli Ednir Oliveira
Published: October 2012

Amino acids are well known to be an important class of compounds for the maintenance of body homeostasis and their deficit, even for the polar neuroactive aminoacids, can be controlled by supplementation. However, for the amino acid taurine (2-aminoethanesulfonic acid) this is not true. Due its special physicochemical properties, taurine is unable to cross the blood-brain barrier. In addition of injured taurine transport systems under pathological conditions, CNS supplementation of taurine is almost null. Taurine is a potent antioxidant and anti-inflammatory semi-essential amino acid extensively involved in neurological activities, acting as neurotrophic factor, binding to GABA A/glycine receptors and blocking the excitotoxicity glutamate-induced pathway leading to be a neuroprotective effect and neuromodulation. Taurine deficits have been implicated in several CNS diseases, such as Alzheimer’s, Parkinson’s, epilepsy and in the damage of retinal neurons. This review describes the CNS physiological functions of taurine and the development of new derivatives based on its structure useful in CNS disease treatment.
Hiding Lipid Presentation: Viral Interference with CD1d-Restricted Invariant Natural Killer T (iNKT) Cell Activation
Authors: Horst Daniëlle , Geerdink Ruben J. , Gram Anna M. , Stoppelenburg Arie J. , Ressing Maaike E.
Published: October 2012

The immune system plays a major role in protecting the host against viral infection. Rapid initial protection is conveyed by innate immune cells, while adaptive immunity (including T lymphocytes) requires several days to develop, yet provides high specificity and long-lasting memory. Invariant natural killer T (iNKT) cells are an unusual subset of T lymphocytes, expressing a semi-invariant T cell receptor together with markers of the innate NK cell lineage. Activated iNKT cells can exert direct cytolysis and can rapidly release a variety of immune-polarizing cytokines, thereby regulating the ensuing adaptive immune response. iNKT cells recognize lipids in the context of the antigen-presenting molecule CD1d. Intriguingly, CD1d-restricted iNKT cells appear to play a critical role in anti-viral defense: increased susceptibility to disseminated viral infections is observed both in patients with iNKT cell deficiency as well as in CD1d- and iNKT cell-deficient mice. Moreover, viruses have recently been found to use sophisticated strategies to withstand iNKT cell-mediated elimination. This review focuses on CD1d-restricted lipid presentation and the strategies viruses deploy to subvert this pathway.
The Baboon (Papio spp.) as a Model of Human Ebola Virus Infection
Authors: Perry Donna L. , Bollinger Laura , L.White Gary
Published: October 2012

Baboons are susceptible to natural Ebola virus (EBOV) infection and share 96% genetic homology with humans. Despite these characteristics, baboons have rarely been utilized as experimental models of human EBOV infection to evaluate the efficacy of prophylactics and therapeutics in the United States. This review will summarize what is known about the pathogenesis of EBOV infection in baboons compared to EBOV infection in humans and other Old World nonhuman primates. In addition, we will discuss how closely the baboon model recapitulates human EBOV infection. We will also review some of the housing requirements and behavioral attributes of baboons compared to other Old World nonhuman primates. Due to the lack of data available on the pathogenesis of Marburg virus (MARV) infection in baboons, discussion of the pathogenesis of MARV infection in baboons will be limited.
Asymmetric Brønsted acid-catalyzed aza-Diels–Alder reaction of cyclic C-acylimines with cyclopentadiene
Authors: Rueping Magnus , Raja Sadiya
Published: October 2012

A new chiral Brønsted acid-catalyzed aza-Diels–Alder reaction of cyclic C-acylimines with cyclopentadiene has been developed. The reaction provides optically active aza-tetracycles in good yields with high diastereo- and enantioselectivities under mild reaction conditions.
Preoperative antibiotic prophylaxis practice and guideline adherence in Jordan: a multi-centre study in Jordanian hospitals
Authors: Al-Azzam Sayer I , Alzoubi Karem H , Mhaidat Nizar M , Haddadin Rania D , Masadeh Majed M , Tumah Haitham N , Magableh Arabieh , Maraqa Noor K
Published: October 2012

Introduction: The use of antimicrobial prophylaxis for surgical procedures is one of the measures employed to prevent the development of surgical site infections (SSI). The appropriate choice of antimicrobial agents, dosage regimen, timing, duration and use of intravenous route must be evidence based. This study aimed to assess the practice of surgical antibiotic prophylaxis and adherence of practitioners to the American Society of Health-System Pharmacists (ASHP) guidelines for antimicrobial prophylaxis in surgery and to explore reasons for non-compliance. Methodology: A cross-sectional study was conducted in 20 Jordanian hospitals from October 2006 to June 2007. A questionnaire was designed to collect information from physicians regarding the practice of surgical antibiotic prophylaxis (SAP), references used for guiding SAP practice, prevalence of surgical site infection (SSI), and causative microorganisms. Results: SAP was employed in almost all surgical departments of hospitals. The improper timing of antimicrobial administration for SAP was attributed to lack of knowledge of the guidelines (46.1%), while the improper antimicrobial choice was ascribed to drug unavailability (61.8%). Conclusion: This study shows that physicians are aware of the importance of antimicrobial prophylaxis before surgical procedures. However, further efforts are needed to ensure the implementation of the standard SAP guidelines in Jordanian hospitals.
Trichocomaceae: biodiversity of Aspergillus spp and Penicillium spp residing in libraries
Authors: Leite Júnior Diniz Pereira , Yamamoto Ana Caroline Akeme , Amadio Janaína Vasconcellos Ribeiro de Souza , Martins Evelin Rodrigues , Do Santos Fabio Alexandre Leal , Simoes Sara de Almeida Alves , Hahn Rosane Christine
Published: October 2012

Introduction: Atmospheric air is the most common vehicle for the dispersion of fungi. Fungi belonging to the genera Aspergillus and Penicillium are cosmopolitan and are classified in the family Trichocomaceae. Species of the genera are commonly found in soil, decaying organic materials, animal feed, stored grains, and other materials. This study aimed to determine the taxonomic diversity of airborne fungi of the genera Aspergillus and Penicillium residing in the dust of library environments to contribute to current knowledge of these characteristic genera. Methodology: Three libraries in the city of Cuiaba, State of Mato Grosso, Brazil, were selected as the study areas. A total of 168 samples were collected at randomized sites within each library in areas containing journals, archives, in study rooms, and in collection storage areas in two different periods, the dry season (n = 42)  and the rainy season (n = 42). Samples were collected by exposing Petri dishes containing Sabouraud agar with chloramphenicol to the environmental air. Additional samples were collected with sterile swabs which were rubbed over the surface of randomly chosen books on the shelves; the swabs were subsequently incubated in the laboratory. Results and conclusion: The genus Aspergillus was highlighted as one of the principal airborne fungi present in indoor environments. Aspergillus spp was identified in 1,277 (89.6%) samples and Penicillium spp in 148 (10.4%). The dry period exhibited a greater number of isolates of the two taxons.
Immunological evaluation of OMP-F of native Iranian Pseudomonas aeruginosa as a protective vaccine
Authors: Ahmadi Hojat , Tabaraie Bahman , Maleknia Shayan , Pormirzagholi Farahnaz , Nejati Mehdi , Hedayati Mohammad Hosein
Published: October 2012

Introduction: This study involved 300 Pseudomonas aeruginosa strains isolated from patients admitted in four Tehran hospitals. Using standard O-specific typing sera, they were all grouped into 16 strains out of 17 known P. aeruginosa. The strains were lyophilized and each was given a code according to the Collection of Standard Bacteria, Pasteur Institute of Iran (CSBPI) for further investigations. Methodology: Among all clinical samples, CSBPI: 16-190 was the most prevalent P. aeruginosa serotype which showed a high agglutination titer (4+, 320) against homologous O-specific typing sera. This serotype was selected for extraction of P. aeruginosa major outer membrane vesicles (OMP-F). OMP-F vesicles were extracted and purified according to the Deoxycholate Ultracentrifuge Differentiation Technique. Purity and molecular weight of OMP-F were determined by SDS-PAGE and the ability of OMP-F vesicles to induce high titers of antibody in rabbit, which was shown as a sharp antibody-antigen precipitation line in the agarose gel immune-diffusion technique. Results: Passive immunization of mice with anti-rabbit OMP-F antisera induced a high level of protection when the mice were post-challenged with 2×LD50 of live P. aeruginosa CSBPI: 16-190. Furthermore, active immunization of mice with 50 µg of OMP-F could protect mice against 2×LD50 of live homologous (100% protection) and 15 heterologous native Iranian P. aeruginosa serotypes with 50-100% level of protection. Conclusions: These investigations indicate that purified OMP-F of CSBPI: 16-190 can be regarded as a safe protective immunogen in vaccinothrapy against all P. aeruginosaimmunotype isolated in Iran.
Distribution of erythrocyte binding antigen 175 (EBA-175) alleles and ABO blood groups in a hypoendemic area in Senegal
Authors: Badiane Aida Sadikh , Sarr Ousmane , Deme Awa Bineta , Ahouidi Ambroise Dioum , Gueye Papa Elhadji Omar , Ndiaye Mouhamadou , Seck Mame Cheikh , Diallo Mouhamadou , Bei Amy Kristine , Duraisingh Manoj T , Wirth Dyann , Ndiaye Daouda , Ndir Omar , Mboup Souleymane
Published: October 2012

Introduction: The study was conducted to determine for the first time the association between the erythrocyte binding antigen 175 (EBA-175) alleles and ABO blood groups in malaria patients living in Thies, a hypoendemic area in Senegal. Methodology: In 2007, the EBA-175 alleles and blood group types were determined by nested PCR and the Simonin test respectively in blood samples obtained from uncomplicated Plasmodium falciparum malaria positive patients. Results and conclusion: In total, 129 patients were enrolled in the study. The EBA-175 genotyping showed a prevalence of 67.45% for the F-allele, 27.90% for the C-allele and 4.65% of mixed C+F infection. The distribution of the ABO blood group type showed 59.8% for the O group, 19.7% for the A group, 17.2% for the B group, and 3.3% for the AB group. No correlation was noted between the EBA-175 alleles and either the blood group type or parasitemia.
Centripetal external quality assessment for laboratories located in remote and rural areas
Authors: Arya Subhash C , Agarwal Nirmala
Published: October 2012

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