bluuebunny/crossref_metadata_2025 huggingface dataset:
Documentation of Risk and Cost-reducing Potential by Utilizing an Automatic Supervision and Decision Support System During Drilling a Challenging HPHT Well
Authors: Rommetveit Rolv , Ødegård Sve Inge , Nordstrand Christine , Bjørkevoll Knut S. , Fjeldheim Mikkel
Published: March 2011

A very challenging HPHT well has been drilled while running an advanced decision support and ECD Management System including early diagnosis of upcoming problems and real time simulations using state-of-the art mathematical models. The System has been running in parallel with the operation, and used all available real time drilling data (surface and downhole) in combination with real time modelling to monitor and optimize the drilling process. This information was also used to visualize the wellbore in 3D in real time. Automatic forward-looking of ECD was also part of the active system. It was implemented in Total E&P Norge TASC (Total Activities Support and Collaboration) Center in Norway. The System was piloted by Total, and was therefore not integrated in Total's work and decision process.

Among the challenges during planning and drilling of this well have been Very small window between pore and fracture pressure. RT ECD simulations were performed with an advanced hydraulic and thermal wellbore modelIncreased probability for instabilities in the tight window. This was mitigated in the System by RT stability modeling during drillingUncertainties in pore pressure predictions. This was mitigated in the System by updating predictions during drilling.

Experiences from use of the System clearly show: -The forward-looking capability gave early warning of a near-future kick situation. And the diagnosis functionality gave first an early warning of an upcoming kick and then a firm diagnosis.-A loss situation was warned against and eventually diagnosed by the System.-Potentially at least 10 rig days, large amounts of drilling mud and a squeeze cement job could have been avoided by fully utilizing the System.-The drilling risks could have been reduced and safety increased through reducing the impact of the kick/loss situations and possibly even avoiding them.
Case History: Lessons Learned From Retrieval of Coiled Tubing Stuck by Massive Hydrate Plug When Well Testing in an Ultra-Deep Water Gas Well in Mexico
Authors: Arrieta Victor Vallejo , Torralba Aciel Olivares , Hernandez Pablo Crespo , García Eduardo Rafael , Maia Claudio Tigre , Guajardo Michael
Published: March 2011

A well testing operation was performed to confirm productivity potential in an ultra-deepwater area where a 5660-ft exploratory well had been drilled. This was a gas well, drilled from a semi-submersible drilling rig. As well testing from submersible rigs is a critical and sensitive operation; all planning had been carefully reviewed by the operator to ensure a safe, environmentally friendly operation.

The formation of hydrate plugs during ultra deepwater well testing is a critical concern, since water can be trapped and form a solid crystalline structure around gas when there are low temperatures near the mud line. This hydrate formation is a common occurrence in deepwater drilling operations, particularly while using water-based mud. Thermo-dynamic inhibition may not be effective in these cases, as several limitations in achieving the required injection rate exist.

Oilwell testing operations in deep and ultra-deep water have become common practice around the world, and vast experience with these types of operations has been acquired; experience with gas wells, however, has not been as comprehensive, and only a few gas wells have been tested under the conditions presented in this type of scenario. Because of the low number of gas wells tested in these deepwater conditions, best practice information is limited.

The intention of this paper is to present a case history and the lessons learned during a well testing operation in which water production in the gas-well was greater than anticipated during the clean-up period. A massive hydrate plug was formed while coiled tubing was being pulled out of hole, and the coiled tubing became stuck. The steps taken to free the coiled tubing will be discussed, and the discussion will include: Conditions that must be present to form hydratesHow the problem in this case was resolvedHow to help prevent hydrate formationBest practices for well testing in deep-water gas wells to maintain safety and economic viability.

This case history discusses a gas well being drilled with a semi-submersible drilling rig in ultra deep water, offshore Mexico.
FMECA and Commissioning - Guidelines to Effectively Deliver Technology and Systems for Successful Drilling Automation
Authors: de Wardt John , Moore Tom , McKenzie Andy
Published: March 2011

Failure Mode Effects and Criticality Analysis (FMECA) is a very powerful tool used in high risk businesses to deliver reliability. This is a known methodology applied in aerospace, nuclear and Dynamic Positioning (DP) systems that can be translated to drilling and completion operations.

Commissioning is the transition process between construction and operation that is widely used in process plants – from onshore chemicals to offshore production installations. It is a known methodology to ensure start up and operation meet specifications.

The drilling business has applied these tools to a very limited extent. When FMECA is used it is typically applied to a single component (i.e. drawworks) not the entire rig or system. Commissioning also tends to be done at the major component level rather than as an integrated facility. As the integration of systems in the drilling process grows these tools become very pertinent to reducing risk especially as wells become more complex and costly. They are the foundation of reliability for Automated Drilling Systems. Without applying tools that can deliver reliability in a manner that is cost effective a lot of value will be lost through unnecessary downtime and failures.

Participants at the SPE Emerging Technologies Workshop May 2009 and the SPE Drilling Automation Workshop April 2010 observed that they had limited knowledge of FMECA; however, after familiarization they concluded that this is a powerful tool that must be used to establish reliability of technologies and systems. The latter workshop concluded that the industry must focus on the application of FMECA and create standards for commissioning.

This paper has been created through a team of experts compiling their knowledge and guidance to provide a knowledge base for the industry to utilize for the benefit of increased reliability and reduced risk.

These two tools, properly and efficiently applied will bring immense value to the industry in terms of reliability. Specifically their application to the control and automation of the drilling process will provide the basis for successful growth of this technology application. Without correct application of these tools, growth of technologies and automated systems in drilling will be inhibited by unacceptable levels of reliability.
Predicting Salt Leaching During Drilling and Cementing Operations
Authors: Folsta M. G. , Martins A. L. , Lomba R. F. , Cardoso W. F. , Simão C. A. , Sidi I. A. , Dannenhauer C. E.
Published: March 2011

Drilling and completion operations in salt zones have been gaining importance in Brazil due to the discovery of large reserves of oil and gas reservoirs in the Pre-Salt zone. Thus, the pursuit of excellence in such operations, reduction of uncertainties, risks and costs are requiring considerable development of new operational practices and technologies.

The well salt surface in contact with non-saturated fluid results in leaching process. In drilling operations the continuous leaching of a given salt formation results in a "V" caliper profile. The drilling of different salts (e.g. halite, tachyhydrite and carnalite) can result in localized enlargements compromising well stability and subsequent operations. In cementing operations the thickening time and cement tensile strength are dependent on salt concentration being critical to control its maximum values at the end of the displacement.

This work details a salt solubilization study to be used both for drilling and cementing operations in salt zones. The software developed aims to estimate the amount of salt incorporated by the drilling fluid or the cement slurry during the fluids flow in contact with the salt formation. The software is based on the solution of the mass conservation equation for a component (salt) in the fluid that flows through the annular region of the well. The partial differential equations obtained in the transient 2D model were numerically solved by using the finite volume method. The formulation takes into account the mass transfer from the well salt wall and also from the drilled cuttings. Radial and axial diffusion and advection terms are considered.

Typical results obtained by the software are the diameter profile along the well and the profile of salt incorporated into the fluid. The methodology is a powerful design tool for defining initial salt concentration, flow rates and rheological properties of drilling fluids and cement slurries
Acquiring Formation Pressure Measurements in Challenging Borehole Conditions
Authors: Piber M , Ash S. C. , Hemsing J. , Kuchinski R. S.
Published: March 2011

Horizontal and multilateral wells are being drilled as a cost-effective approach to increasing production and adding reservoir value. The data acquisition strategy makes extensive use of formation pressure measurements that are critical to the understanding of the economic potential of a reservoir. Conventional formation testing techniques have proven inadequate for determining producibility and formation pressures in horizontal and highly deviated wells due to high costs and extreme operational risks. In this paper, a low-risk solution is described for obtaining early history formation pressures in these challenging borehole conditions using a very small sized formation tester combined with robust new operational planning, practices, and techniques.

The Compact Repeat Formation Tester (MFT), of diameter approximately 2.4 inches, was deployed in memory mode and conveyed to test depth. Extensive operational planning and pre-job modelling was completed to allow for optimum data acquisition while minimizing total operation time. Well conditions prohibited the formation tester from providing real-time surface communication, the formation tester was programmed to accommodate as wide of range of test scenarios as possible.

All tool data were stored in onboard memory for retrieval after the formation tester returned to surface. Twenty two pressure stations were attempted in two wells to a depth of 2250m under borehole conditions where information is usually not attainable. The data obtained from the stations was of good quality and the pressure results were subsequently confirmed by production.

Several examples are presented to demonstrate this new technique was successful in obtaining pressure data of highest quality and confidence allowing reservoir insights that would otherwise have been unavailable. The ability to take pressures at multiple stations throughout the reservoirs has produced a detailed understanding of critical economic information. Additionally further developments allow very near time transmission of drawdown pressures back to surface to allow for instant analysis.
Application of a New Method for Predicting Down Hole Loading of Tubulars During Expansion
Authors: Evans Merle E. , Setterberg John R.
Published: March 2011

This paper describes the loads experienced by solid expandable tubulars during down hole expansion. These loads are compared to the loads experienced by tubulars when expanded using current laboratory techniques. The paper demonstrates that the current practices for expanding test samples do not necessarily represent all of the loads that can be experienced in situ. The loads that are excluded in making expanded thread connection test samples may have significant impact on the performance of the threaded connections. Newly developed testing methods and equipment that have been used to replicate the actual down hole loads that are generated when casing is expanded will be described, and data generated from the testing of samples made with the new equipment presented.
Extended Reach Drilling - Offshore California. Extending Capabilities and Improving Performance
Authors: Armstrong Neil R. , Evans Andrew M.
Published: March 2011

El Capitan is the latest extended reach drilling (ERD) well to be drilled from the Heritage Platform into the Sacate Field, offshore California. The application of learnings from previous wells enabled El Capitan to be drilled to a total depth of 37,165 ft measured depth (MD) / 6,938 ft true vertical depth (TVD) with 33,682 ft of horizontal displacement (HD). The most challenging phases of the well will be described in this paper, concentrating on the main engineering focus areas during planning and execution.

El Capitan holds the record for the longest well drilled in North America and is the third longest directional well drilled worldwide by MD (seeFig. 1). El Capitan also holds the record for the deepest (MD) 12-1/4-in. hole section and the deepest (MD) set 9-5/8-in. liner. Application of the company's recently modified Fast Drill Process (FDP) emphasizing the redesign of borehole related performance limiters enabled a 250% improvement in drilling performance from offsets in the 12-1/4-in. and 8-1/2-in. hole sections (Dupriest et al., 2010). Casing floatation techniques used on previous wells in the field were refined to enable a 27,267 ft long 9-5/8-in. liner to be successfully run to the 12-1/4-in. hole section total depth (TD). The well objectives were achieved with no safety or environmental incidents, 92 days ahead of plan, significantly under budget and with only 15% non-productive time (NPT).
The Continuous Measurement and Recording of Drilling Fluid Density and Viscosity
Authors: Miller A. , Minton R. C. , Colquhoun R. , Ketchion M.
Published: March 2011

The density and viscosity of the circulating drilling fluid are currently monitored at intervals of 15 to 30 minutes. These intermittent manual measurements are time consuming, entail a continuous presence in the shale-shaker house, are open to user error and are seldom widely communicated. Yet these measurements can offer an indication of developing drilling fluid or bore-hole problems that, if caught early, could minimise developing hole problems or limit operational delays.

This paper presents the field results of the use of a novel instrumentation package that continuously monitors these properties, exports the data to the logging data-base, permits trend analysis and the wider promulgation of the information, mitigating the limitations of the current approach.

The design of the package is such that there is no longer a requirement for manual sampling. This frees up the Derrickman / Shaker-hand for more productive tasks and minimises exposure to the noise and fumes of the shaker-house. Also, the simple, rugged, build means that it can be operated and maintained without the need for dedicated service engineers. Additionally, monitoring is still possible should the shaker house become unbearably hot, the hydrocarbon gas levels are too high or even if noxious gases are present in the enclosure.

The data is collected at 10 second intervals. This vastly increased granularity of the data set permits the identification of short duration ‘spikes’ possibly indicative of incipient Barytes sag, fluid channelling, fluid interfaces, etc. It also means that trends can be identified earlier and remedial steps taken to pre-empt developing problems.

Data will be presented from an HP/HT drilling operation in the UK sector of the North Sea. These measurements will be compared with manual readings, as a measure of their veracity, and weight and viscosity signatures / trends will be identified and correlated with known events.
Anaerobic‐Fed and Sequencing‐Batch Treatment of Sugar‐Beet Processing Wastes: A Comparative Study
Authors: Alkaya Emrah , Demirer Göksel N.
Published: March 2011

The aim of this study was to compare a batch‐fed continuously mixed anaerobic reactor (FCMR) with an anaerobic sequencing batch reactor (ASBR), in terms of waste stabilization and methane production treating sugar‐beet processing wastewater and beet‐pulp simultaneously. A reactor was operated as FCMR, which then was operated as an ASBR by changing operational conditions after the steady‐state was reached. Although the hydraulic retention time value of the ASBR configuration was lower (8 days) than that of the FCMR (15 days) and the corresponding organic loading rate (OLR) was higher (0.71 to 1.33 g COD/L·d), increased biomass retention enabled a significant increase in biomethanation for the ASBR configuration. So, methane production yield of 255 ± 11 mL/g COD‐added was increased to 337 ± 15 mL/g COD‐added (32.2% increase in methane yield) when the configuration was changed from FCMR to ASBR. The experimental results indicated that the ASBR configuration, which was applied to sugar‐beet processing wastes for the first time, was superior to the FCMR configuration.
Research Advances and Challenges in the Microbiology of Enhanced Biological Phosphorus Removal—A Critical Review
Authors: Gebremariam Seyoum Yami , Beutel Marc W. , Christian David , Hess Thomas F.
Published: March 2011

Enhanced biological phosphorus removal (EBPR) is a well‐established technology for removing phosphorus from wastewater. However, the process remains operationally unstable in many systems, primarily because there is a lack of understanding regarding the microbiology of EBPR. This paper presents a review of advances made in the study of EBPR microbiology and focuses on the identification, enrichment, classification, morphology, and metabolic capacity of polyphosphate‐ and glycogen‐accumulating organisms. The paper also highlights knowledge gaps and research challenges in the field of EBPR microbiology. Based on the review, the following recommendations regarding the future direction of EBPR microbial research were developed: (1) shifting from a reductionist approach to a more holistic system‐based approach, (2) using a combination of culture‐dependent and culture‐independent techniques in characterizing microbial composition, (3) integrating ecological principles into system design to enhance stability, and (4) reexamining current theoretical explanations of why and how EBPR occurs.
Characterization of Natural Ventilation in Wastewater Collection Systems
Authors: Ward Matthew , Corsi Richard , Morton Robert , Knapp Tom , Apgar Dirk , Quigley Chris , Easter Chris , Witherspoon Jay , Pramanik Amit , Parker Wayne
Published: March 2011

The purpose of the study was to characterize natural ventilation in full‐scale gravity collection system components while measuring other parameters related to ventilation. Experiments were completed at four different locations in the wastewater collection systems of Los Angeles County Sanitation Districts, Los Angeles, California, and the King County Wastewater Treatment District, Seattle, Washington. The subject components were concrete gravity pipes ranging in diameter from 0.8 to 2.4 m (33 to 96 in.). Air velocity was measured in each pipe using a carbon‐monoxide pulse tracer method. Air velocity was measured entering or exiting the components at vents using a standpipe and hotwire anemometer arrangement. Ambient wind speed, temperature, and relative humidity; headspace temperature and relative humidity; and wastewater flow and temperature were measured. The field experiments resulted in a large database of measured ventilation and related parameters characterizing ventilation in full‐scale gravity sewers. Measured ventilation rates ranged from 23 to 840 L/s. The experimental data was used to evaluate existing ventilation models. Three models that were based upon empirical extrapolation, computational fluid dynamics, and thermodynamics, respectively, were evaluated based on predictive accuracy compared to the measured data. Strengths and weaknesses in each model were found and these observations were used to propose a concept for an improved ventilation model.
Bioenergy II: The Development of a Reactive Distillation Process for the Production of 1,1 Diethoxy Butane from Bioalcohol: Kinetic Study and Simulation Model
Authors: Agirre Ion , Barrio V. Laura , Güemez Belen , Cambra Jose F. , Arias Pedro L.
Published: March 2011

1,1 Diethoxy butane was produced carrying out the reaction between ethanol and butanal in a batch stirred reactor using Amberlyst cation-exchange resins as catalyst. The kinetics of this reaction was studied working at different temperatures, feed compositions and catalyst type and loadings. Due to thermodynamic limitations, maximum conversions are quite low for kinetically acceptable temperatures. That is why the kinetic information gathered has been used to develop a model for reactive distillation, which has predicted promising results.
Flow Study and Wetting Efficiency of a Perforated-Plate Tray Distributor in a Trickle Bed Reactor
Authors: Ramajo Damian Enrique , Marquez Damian Santiago , Raviculé Marcela , Monsalvo Maria M. , Storti Mario , Nigro Norberto
Published: March 2011

In this work, a computational fluid dynamics analysis (CFD) employing the Eulerian two-fluid model was carried out with the aim to understand the distribution process and to determine the wetting efficiency of the primary tray distributor (perforated plate) of a trickle bed reactor (TBR) under several operating conditions. The overall inlet geometry was considered, and the small holes of the perforated plate were modeled by sinks (drains) and sources, employing CFD and experimental models to obtain the hole discharge flow coefficients. The influence of the ceramic-ball bed above the catalyst bed was considered by a suitable correlation to estimate liquid distribution inside it.Results showed that because of the scarce liquid sloshing above the tray, little difference on liquid flow rate through the tray holes was found. Due to the really low inlet mass flow rate of gas, it has negligible influence on liquid behavior, which drops through holes slowly without spraying. Thus, the ceramic-ball bed above the catalyst bed is exclusively wetted in a small area under the tray holes. Although the ceramic-ball bed improves liquid distribution, which guarantees a minimum liquid volume fraction at all places, significant differences on the liquid mass flow rate across the top of the catalyst bed were found. Additional causes of low efficiency in TBR like the well-known fouling vulnerability of perforated-plate trays and unevenness were analyzed. For the first, two simple modifications were proposed to improve tray performance: reducing the amount of gas chimneys to only one and adding additional drip points and replacing the tray holes by short risers in order to avoid plugging.
Acute Toxicity and Antioxidant Activity of Hydroethanolic Extract of Solenostemon monostachyus P. Beauv. Leaves
Authors: Jacques Datté Y , Fidele Kpahe , Michel Offoumou A
Published: March 2011

Acute toxicity and antioxidant activity of hydroethanolic leaves extract of Solenostemon monostachyus (Esomo) were investigated. The method used for antioxidant evaluation was 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) and the method of Miller & Tainter was employed for the acute toxicity. The lethal dose inducing death for half of tested mice (LD50) for Esomo was 1.9± 0.001 g/kg body weight. According to the classification of Diezi (1989), this drug is weakly toxic. Esomo's concentration at 50% DPPH radical scavenging activity (IC50) was 19.95 ± 0. 1µg/ml. Esomo (100 µg/ml) induced a DPPH scavenging activity of 86.25 %. Similar results were obtained with acid gallic and ascorbic acid applied at the same concentration and they induced a DPPH scavenging activity of 91.66% and 98%, respectively. Our results show that the extract of S. monostachyus exhibits an antioxidant property. The property is due to the presence of phenolic compounds, such as flavonoids, tannins, coumarins, sterols and terpins, shown in the former phytochemical study. The weak toxicity and the significant antioxidant activity of leaves of S. monostachyus could explain its use in folk medicine.
Effect of the Microwave Irradiated Treatment on the Wine Sensory Properties
Authors: Zheng Xianzhe , Liu Chenghai , Huo Junwei , Li Cong
Published: March 2011

An instantaneous microwave irradiation method was applied to treat young dry red wine in order to accelerate the desired aging process during storing wine for the improvement of its taste quality. Effects of the microwave power and irradiation duration on the wine sensory property were investigated. Experimental results showed that microwave treatment had a significant effect on taste and total score, but no obvious effect was found on appearance, fragrance, fragrance duration and overall assessment. The influence of irradiation duration was significant on appearance, fragrance and total score, while not obvious on other indexes. The optimum conditions were obtained with microwave power 420 W and irradiation duration 5 min, and the result was corresponding to the content of chemical constituents of treated wine.
Optimization of Cellulase Production Using Agricultural Wastes by Artificial Neural Network and Genetic Algorithm
Authors: Chang Chun , Xu Guizhuan , Yang Junfang , Wang Duo
Published: March 2011

The cellulase production by Trichoderma viride was optimized using artificial intelligence-based techniques under solid state fermentation. In this study, a back propagation network was designed with Levenberg-Marquardt training algorithm, and the tangent sigmoid and pure linear functions were used as the transfer functions in the hidden and output layers of the ANN, respectively. An artificial neural network coupling genetic algorithms was used to optimize the process parameters, which include the mass ratio of wheat straw to wheat bran, moisture content and fermentation time. The ultimate process parameters of optimization were mass ration of wheat straw to wheat bran 2.9, moisture content 69.6 percent, and fermentation time 123.3h. Further test experiment showed that the final cellulase activity can reach to 11.62 U/g, which was the highest value among all the experimental results. This result indicates that the genetic algorithm based on a neural network model is a better optimization method for cellulase production in solid state fermentation. To improve the cellulase production, a mixed culture system of Trichoderma viride and Aspergillus niger was also developed. The cellulase activity increased by 7.40 percent with the addition of Aspergillus niger at 72h.
Selected aspects of territorial cohesion in Slovakia under the recent crisis
Authors: Jasso Matej , Finka Maros
Published: March 2011

Territorial cohesion has been one of the most prominent topics of discourse
among spatial planners, urban sociologists, economists and experts from
various other fields. Territorial systems with high degree of cohesion are
better equipped to withstand the external pressures and situational
imbalancies. Recent global crisis exposed these imbalancies and challenged
the smooth and balanced spatial development of European countries. Major
economic setbacks influenced entire society in Slovakia. Global financial
crisis evaporated the ultimate growth of Slovak economics and exposed hidden
imbalancies of development policies solely related to GDP growth instead of
creating the fundaments for sustainability in the transition economy. Spatial
polarization on different levels of society weakened down the overall (mainly
social) cohesion and highlighted the problems of marginalized regions and
social groups. Social aspects of territorial and spatial processes are more
visible than ever before and regional disparities are becoming more prominent
issue in political and scientific discourse. Despite the deep profilation of
regional identity and place attachment, there are still considerable
distinctions and disparities between metropolitan/urban and rural communities
in terms of values, consumption patterns, life style, sense of solidarity or
wealth distribution. Selected aspects of territorial cohesion in Slovakia,
mainly in the field of social cohesion are in the spotlight in this paper.
Focus on integrative spatial development balancing the contradictions by
effective mixture of general approach and reasonable and sensible
differentiation is considered highly essential.
Strategic planning for sustainable spatial, landscape and tourism development in Serbia
Authors: Maksin Marija , Milijic Sasa
Published: March 2011

The paper presents an overview of the expected role of spatial and
environmental planning in coordination and integration with strategic
planning for sustainable spatial/territorial, landscape and tourism
development. The application of an integrated approach to sustainable
territorial development planning and management in the European Union is also
analyzed in the context of problems associated with and possibilities to
enhance the European Landscape Convention and Agenda for a sustainable and
competitive European tourism implementation. We have analyzed the
contributions of reforms that have so far been implemented in current
legislation and of planning bases to the establishment of coordinated
sustainable territorial development planning and management in Serbia and to
the procurement of support for the integration of sustainable tourism
development and landscape planning and management into the process of
spatial, environmental and sectoral planning. The approach to and problems of
landscape protection and sustainable tourism development occurring in the
practice in spatial planning are analyzed through examples of a new
generation of spatial plans - the Spatial Plan of the Republic of Serbia, and
a spatial plan of the special-purpose area for the Nature Park and Tourism
Region of Stara Planina Mountain. Through the example of Mt Stara Planina,
the role of strategic environmental assessment in coordination with spatial
and sectoral planning is analyzed, as well as potential contribution to
landscape integration and sustainable tourism development in the process of
planning. The possibilities for better coordination of Serbian strategic
planning in achieving the sustainable spatial and tourism development, and
possibilities to integrate landscapes into the planning process are
indicated.
Marc-Antoine Laugier’s aesthetic postulates of architectural theory
Authors: Kuletin-Culafic Irena
Published: March 2011

Views on architecture that hold a significant position in architectural
theory are the ones by Marc-Antoine Laugier, a French theoretician from the
18th century. The research on his architectural theory that have been carried
out so far are quite stereotypical and concern Laugier?s concept of primitive
hut as his only significant contribution to architectural theory. It is
well-known that the concept of primitive hut plays an important role in
Laugier?s theory and it is what actually maintained his reputation up to now.
However, by singling out this concept as an independent one, one actually
neglects all the other aspects of Laugier?s theory. The aim of this paper is
to present multidimensionality of Laugier?s architectural aesthetics by
crossing the borders of architecture and viewing Laugier?s ideas in cultural,
philosophical, religious and historical context, as well as applying the
integrative process and considering the spiritual paths of the enlightenment
movement in the mid-18th century. A special attention is paid to considering
the aesthetic aspect which represents the gist and an inevitable part of
Laugier?s architectural theory. His aesthetic theory is important in forming
the classicist style, and despite its radical character, it influenced many
architects in France and the rest of Europe. We may see Laugier as one of the
first modernists considering his structuralist logic of the constructive
circuit of architecture and aesthetic modesty of decoration. Laugier?s
functionalist attitude that the constructive circuit should at the same time
represent a decorative element of architecture confirms the thesis that
modernist approach has its roots in the 18th century.
Teacher leadership and educational innovation
Authors: Frost David
Published: March 2011

This national conference was arranged by the Ministry of Education to support
the drive to modernize the education system as a whole. This paper is based
on David Frost?s presentation which explored the links between a
transformative view of education, the nature of innovation and the need to
develop teacher leadership. It is argued that, in transformative education,
learning centres on the cultivation of capacities and dispositions. These are
exemplified and illustrated. Key concepts such as agency, meta-learning,
self-regulation and their link to citizenship are explained. The distinction
is drawn between implementation and innovation as a process which is both
long and arduous. It is argued that such a process of innovation demands
learning at all levels (students, teachers, the school, the system), but
teacher leadership is where the most potential lies. Stories of teacher
leadership are used to illustrate what can be achieved and claims are made as
to the benefits of teacher leadership. It is claimed that teacher leadership
can mobilise teachers? capacity for leading change, improve quality in the
system and build professional knowledge that teachers trust. The paper
concludes by outlining the theory of teacher leadership promoted by the
International Teacher Leadership project.
Strategies identification in an experimental reading comprehension task
Authors: Stankovic Sanda , Lalovic Dejan
Published: March 2011

Standardized reading comprehension tests (RCTs) usually consist of a small
number of texts each accompanied by several multiple-choice questions, with
texts and questions simultaneously presented. The score the common measure of
reading comprehension ability in RCTs is the score. Literature review
suggests that strategies subjects employ may influence their performance on
RCT, however the score itself provides no information on the specific
strategy employed. Knowledge of test-taking strategies could have impact on
understanding of the actual purpose and benefits of using RCTs in pedagogical
and psychological practice. With the ultimate objective of constructing a
first standard RCT in Serbian language, the preliminary step we took was to
conduct an experimental reading comprehension task (ERCT) consisting of 27
short texts displayed in succession, each followed by a single multiplechoice
question. Using qualitative analysis of subjects? responses in
semi-structured postexperimental interview, we identified four overall
strategies used on ERCT. Our results show that groups of students who used
specific strategies differed significantly from one another in text reading
time, with no differences found regarding the question reading and answering
time. More importantly, there were no significant between-group differences
found in terms of ERCT score. These findings suggest that choice of strategy
is a way to optimize the relation between one?s own potential and ERCT task
requirements. RCT based on ERCT principles would allow for a flexible choice
of strategy which would not influence the final score.
Influence of problem-based teaching and learning of grammar on pupils’ attainment in primary school
Authors: Jocic Zorica
Published: March 2011

With the purpose of getting an insight into the effects of problem-based
teaching and learning, an experiment was carried out by using the method of
parallel groups on the sample of 204 pupils in the third and sixth grade of
primary school. The results of final knowledge assessment showed that
problem-based teaching and learning of grammar had positive influence on
pupils' attainment comparing to the usual way of learning grammar. A
significant improvement has been achieved in the field of reproductive and
productive grammar knowledge on the whole sample of pupils as well as on the
subsamples of pupils in the third and sixth grade. Because of the limited
time left for this experimental programme, the reproductive knowledge of
pupils was bigger than the productive knowledge. It has been noticed that
regarding the successfulness of solving the grammatical problems, there was
no difference between the pupils of younger and older primary school age, in
the situation when these problems were decided on according to their age and
intellectual abilities. All pupils had made an improvement, but they remained
within the range of their marks in Serbian language. In addition to this,
better progress was made by the pupils with better marks in Serbian language.
Girls were more successful than boys, but the difference between boys and
girls was smaller regarding the reproductive knowledge than the productive
knowledge.
Lesson Learned: Using Clinical Examples for Teaching Research Methods
Authors: Sizemore O.J. , Lewandowski Gary W.
Published: March 2011

Undergraduate students enrolled in their first statistics course were randomly assigned to read one of two mini-lessons about methodological confounds. In one, a therapist investigated a variable that might affect depression; in the other, a researcher investigated a variable that might affect memory. As hypothesised, the clinical lesson produced significantly higher interest in the lesson topic and significantly greater interest in the research described. Participants in the clinical lesson had a higher desire to do research in this area, though this difference only approached significance. Knowledge of the topic (number of correctly answered multiple-choice items) was not significantly different between conditions. These results suggest that placing methodological concepts in clinical contexts may provide a fruitful approach for improving the frequently reported negative student attitudes toward statistics and research methods.
MicroRNA-200b Regulates Vascular Endothelial Growth Factor–Mediated Alterations in Diabetic Retinopathy
Authors: McArthur Kara , Feng Biao , Wu Yuexiu , Chen Shali , Chakrabarti Subrata
Published: March 2011

OBJECTIVE

Diabetic retinopathy (DR) is a leading cause of blindness. Increased vascular endothelial growth factor (VEGF), promoting angiogenesis and increased permeability, is a key mechanistic abnormality in DR. We investigated microRNA (miRNA) alterations in DR with specific focus on miR-200b, and its downstream target, VEGF.

RESEARCH DESIGN AND METHODS

miRNA expression profiling microarray was used to examine the retinas of streptozotocin-induced diabetic rats. Expressions of specific miRNAs were verified with PCR in the rat retina and in glucose-exposed endothelial cells. A target search, based on sequence complementarities, identified specific targets. We analyzed mRNA levels and protein expression in endothelial cells from large vessels and retinal capillaries and in the rat retina, with or without injection of miR-200b mimic or antagomir. Localization of miR-200b and its functional analysis in the rat and human retinas were performed.

RESULTS

Alteration of several miRNAs, including downregulation of miR-200b, were observed in the retina in diabetes. Such downregulation was validated in the retina of diabetic rats and in endothelial cells incubated in glucose. In parallel, VEGF (target of miR-200b) mRNA and protein were elevated. In the retina, miR-200b was localized in neuronal, glial, and vascular elements. Transfection of endothelial cells and intravitreal injection of miR-200b mimic prevented diabetes-induced increased VEGF mRNA and protein. Also prevented were glucose-induced increased permeability and angiogenesis. Furthermore, transfection of miR-200b antagonists (antagomir) led to increased VEGF production. Similar alterations were seen in the human retina.

CONCLUSIONS

These studies show a novel mechanism involving miR-200b in DR. Identification of such mechanisms may lead to the development of novel miRNA-based therapy.
Fasting Indicators of Insulin Sensitivity: Effects of Ethnicity and Pubertal Status
Authors: Adam Tanja C. , Hasson Rebecca E. , Lane Christianne J. , Davis Jaimie N. , Weigensberg Marc J. , Spruijt-Metz Donna , Goran Michael I.
Published: March 2011

OBJECTIVE

To examine the relationship of fasting indicators of insulin sensitivity with a more invasive measure of insulin sensitivity (frequently sampled intravenous glucose tolerance test [FSIVGTT]) and the effect of Tanner stage and ethnicity on that relationship.

RESEARCH DESIGN AND METHODS

Data were analyzed from 149 overweight girls (97 Hispanic and 52 African American) who were either in the early stages of maturation defined by Tanner stages 1 or 2 (52 Hispanic and 18 African American) or in the later stages of maturation defined by Tanner stages 4 and 5 (45 Hispanic and 34 African American). Fasting indicators of insulin sensitivity (IS) included fasting insulin and glucose and the homeostasis model assessment of insulin resistance (HOMA-IR). IS was derived from an FSIVGTT with minimal modeling.

RESULTS

In Tanner stages 1 and 2, all fasting indicators were significantly associated with IS: (fasting insulin: r = −0.67, P < 0.01; HOMA: r = −0.66, P < 0.01) with no significant influence of ethnicity on these relationships. In Tanner stages 4 and 5, however, all fasting indicators were associated with IS in African American girls (fasting insulin: r = −0.55, P < 0.01; HOMA: r = −0.47, P < 0.01), but none of the indicators were significantly associated with IS in Hispanic girls.

CONCLUSIONS

Fasting indicators were reflective of IS for girls in Tanner stages 1 and 2, regardless of ethnicity and may provide a clinical measure of future risk for type 2 diabetes. In the latter stages of maturation, however, more invasive measures are warranted to adequately determine IS in clinical practice.
Investigation of the Microscopic Viscoelastic Property for Cross-linked Polymer Network by Molecular Dynamics Simulation
Authors: Masumoto Y. , Iida Y.
Published: March 2011

The purpose of this work is to develop a new analytical method for simulating the microscopic mechanical property of the cross-linked polymer system using the coarse-grained molecular dynamics simulation. This new analytical method will be utilized for the molecular designing of the tire rubber compound to improve the tire performances such as rolling resistance and wet traction. First, we evaluate the microscopic dynamic viscoelastic properties of the cross-linked polymer using coarse-grained molecular dynamics simulation. This simulation has been conducted by the coarse-grained molecular dynamics program in the OCTA) (http://octa.jp/). To simplify the problem, we employ the bead-spring model, in which a sequence of beads connected by springs denotes a polymer chain. The linear polymer chains that are cross-linked by the cross-linking agents express the three-dimensional cross-linked polymer network. In order to obtain the microscopic dynamic viscoelastic properties, oscillatory deformation is applied to the simulation cell. By applying the time-temperature reduction law to this simulation result, we can evaluate the dynamic viscoelastic properties in the wide deformational frequency range including the rubbery state. Then, the stress is separated into the nonbonding stress and the bonding stress. We confirm that the contribution of the nonbonding stress is larger at lower temperatures. On the other hand, the contribution of the bonding stress is larger at higher temperatures. Finally, analyzing a change of microscopic structure in dynamic oscillatory deformation, we determine that the temperature/frequency dependence of bond stress response to a dynamic oscillatory deformation depends on the temperature dependence of the average bond length in the equilibrium structure and the temperature/frequency dependence of bond orientation. We show that our simulation is a useful tool for studying the microscopic properties of a cross-linked polymer.
Biological activity of new flavonoid from Hieracium pilosella L.
Authors: Gawrońska-Grzywacz Monika , Krzaczek Tadeusz , Nowak Renata , Los Renata , Malm Anna , Cyranka Małgorzata , Rzeski Wojciech
Published: March 2011

Hieracium pilosella L. (Asteraceae) is a well-known plant used in ethno-medicine as its inflorescences are particularly rich in beneficial polyphenolics. This research aimed to elucidate the structure of a new flavone glycoside isolated from the inflorescences of Hieracium pilosella and evaluate its antioxidant, antimicrobial and antiproliferative activities. The chromatographic methods were successfully applied to isolate the new flavonoid. Its structure was determined by subsequent UV, NMR and MS experiments and identified as isoetin 4′-O-β-D-glucopyranoside. Free radical scavenging capacity was examined by measuring the scavenging activity of the new isoetin derivative on 2,2-diphenyl-1-picrylhydrazyl (DPPH). The compound was also screened for spectrum of antimicrobial activity using the agar well diffusion method. Minimum inhibitory concentration (MIC) for Pseudomonas aeruginosa ATCC 9027 was performed by the micro-dilution broth method. The antiproliferative effect of tested glycoside was assessed in two human tumor cell lines derived from lung (A549) and colon (HT-29) carcinoma and cell proliferation was determined by means of MTT method. The tested compound showed high antiradical activity, reducing the DPPH? with EC50 7.9 μM (3.7 µg/ml) and exhibited narrow antimicrobial spectrum among tested microorganisms. The compound was active against Pseudomonas aeruginosa ATCC 9027 (MIC 125 μg/ml) which is prone to causing infections that are difficult to treat due to it developing extremely rapid antibiotic resistance. In the antiproliferative studies, cell proliferation of the colon (HT-29) carcinoma cell line was significantly decreased after exposure to the compound. The results indicate that isoetin 4′-O-β-D-glucopyranoside possesses antioxidant capacity and very promising antibacterial activity and could have uses as an effective antipseudomonal agent as well a antiproliferative agent.
Gallbladder actinomycosis: Is it a complication after radiofrequency ablation with transarterial chemoembolization for hepatocellular carcinoma?
Authors: Han Hyung , Choi Sae , Kim Wan , Song Tae , Choi Sang
Published: March 2011

A 64-year-old man with a history of gallstones, common bile duct stones, chronic hepatitis B virus infection, and hepatic cirrhosis with a Child-Pugh score B was satisfactorily treated for hepatocellular carcinoma with radiofrequency ablation and transarterial chemoembolization. His course, however, was complicated by gallbladder actinomycosis 14 months after treatment, resulting in acute cholecystitis. Such a chain of events suggests that gallbladder actinomycosis may develop after radiofrequency ablation and transarterial chemoembolization in patients who are known to have gallstones and that asymptomatic gallstones should be treated before the application of nonsurgical, but invasive procedures for hepatocellular carcinoma.
A novel data hiding and reversible scheme using SMN blocks in VQ-compressed images
Authors: Huang C. , Wang W. , Wang S.
Published: March 2011

Data hiding is a technique for embedding secret data into cover media. It is important to multimedia security and has been widely studied. Reversible data hiding methods are becoming prevalent in the area because they can reconstruct the original cover image while extracting the embedded data. In this paper, we propose a new reversible method for vector quantization (VQ) compressed images. Our method takes advantages of the relationship among the side match neighbouring (SMN) blocks to achieve reversibility. The experimental results show that the proposed method has higher compression rate and larger capacity than other existing reversible methods.