bluuebunny/crossref_metadata_2025 huggingface dataset:
Careful Planning and Application of an Asymmetric Vibration Damping Tool Dramatically Improves Underreaming While Drilling Performance in Deepwater Drilling
Authors: McCarthy John , Kabbara Alan , Burnett Timm , Forster Ian
Published: June 2012

This paper demonstrates how Forward Synchronous Whirl (FSW), when induced in an underreaming while drilling BHA through the application of an Asymmetric Vibration Damping Tool (AVDT), substantially reduces both stick-slip and lateral vibrations and significantly improves drilling performance. The physics of operation, pre-job planning and modeling, followed by a thorough examination of run data and comparisons to offset wells will be documented and quantified.

The performance of underreaming while drilling assemblies in long salt sections, as well as in pre-salt environments around the world has improved considerably in recent years. However, down-hole vibration still limits rates of penetration and overall drilling efficiency. Often, these long salt sections comprise the most challenging intervals of a deepwater well.

A major development project in the Green Canyon section of the Gulf of Mexico contains wells with hole sections exceeding 9,000 ft in length through salt, and into the pre-salt. In order to evaluate the potential benefits of FSW, an AVDT has recently been added to the drilling assembly while keeping all other variables constant (rig, bit type, BHA, etc).

The results showed that overall penetration rates increased by more than 50% and Stick-Slip (SS) vibration reduced by more than 75%. While there was a substantial across-the-board reduction in vibration and an increase in ROP, the benefits of the AVDT were recognized most in the portion of the hole section where elevated vibration levels typically cause a reduction in ROP as energy is lost to vibration (near the base of salt).

With the addition of the AVDT there was little to no increase in SS, and no decrease in ROP. In fact, on one of the wells that used the AVDT, the final 2,500 ft of the 9,000 ft section was drilled 83% faster than the closest offset (178 fph vs. 97 fph), with 90% less SS vibration. Of the five wells analyzed, three were without the AVDT and two were with. All of the runs in question were with a 14 1/2"-16 1/2" underreaming while drilling, rotary steerable drilling assembly.

This novel approach has wide-spread application in global deepwater basins, particularly in vibration-prone wells. This paper demonstrates how the technology is being applied effectively, and provides a platform for further application.
Different Configurations of Intelligent Well Completions With Three Stacked Frac Packs
Authors: Paternostro Barney
Published: June 2012

This paper compares two recent subsea completions in water depths greater than 2,600 feet in the Gulf of Mexico, and how their different configurations enable selective production from three separate gravel packs through an "intelligent system" with two remotely operated sleeves. The "intelligent system" enables a zone change with remotely controlled sleeves that are functioned from the host production platform.

One completion is designed to produce the two lower gravel packs and, with the upper gravel pack, is capable of future production without subsea well intervention. See Figure 1 to see the flow paths from the gravel packs into the production tubing through the remotely operated sleeves of the "intelligent system". For this completion design the two lower gravel packs will initially flow into the production tubing through the lower remotely operated sleeve of the "intelligent system". To change zones for production, the lower "intelligent" sleeve will be remotely closed to isolate the lower zones and the upper sleeve will be remotely opened to produce the upper zone.

Figure 1 Intelligent Completion with 2 Lower Zones Commingled

The other, more complex completion is configured to produce the two upper gravel packs through the upper remotely operated sleeve of the "intelligent system". The gravel pack assemblies are more complicated to enable annular flow from the two upper gravel packs. This completion design still has the same flexibility to change zones and without well intervention. See Figure 2 to see the flow paths from the gravel packs into the production tubing through the remotely operated sleeves of the "intelligent system".

Figure 2 Intelligent Completion with 2 Upper Zones Commingled

Another very important aspect of a successful subsea intelligent completion is the various methods to isolate the gravel packs until the production tubing and intelligent system is installed. These stacked reservoirs usually have different pore pressures, which complicate the gravel pack pumping process and make isolation necessary. There are several mechanisms used to isolate these reservoirs from each other, but this paper will show the use of pressure operated communication devices (POCD) within the gravel pack assemblies.
Narrow Margin Drilling in Deepwater: Solution Concepts
Authors: Erivwo Ochuko , Adeleye Olayinka
Published: June 2012

Drilling operations are conducted within a pressure window bounded on the lower side by the pressure of the formation fluids exposed in the open hole and on the upper side by the fracture resistance of the formation matrix. The narrowing of this operating margin, as experienced in deepwater environments, increases the technical challenges associated with drilling operations. Typical challenges include a sharp reduction in the maximum allowable open hole drilled depth, well control and exposure to difficult kicks, well breathing or ballooning, the risk of wellbore losses and a requirement to install multiple casing strings to get to TD.

This paper examines the phenomenon of narrow margins in deepwater, the conditions that drive it, and presents a holistic assessment of the available geological, geophysical, engineering and technology solutions for mitigating narrow margin drilling (NMD) conditions. The solution concepts are indexed into a newly developed model called the NMD Solutions Matrix which introduces an NMD intensity scale that provides a measure of the degree of difficulty that can be expected in a well as a result of narrow margin conditions.

The applicability of the model is demonstrated in a history match of three industry case examples in two deepwater regions in the world where NMD conditions were encountered and mitigated. The NMD solutions matrix was also applied to a DW project in the planning phase which yielded insights that more clearly articulated the exposure in the project. The analyses indicate that the model, as a planning tool, has the potential to sharpen the awareness of possible challenges and enable upfront mitigation measures to reduce their impact during execution. Its application thus offers strong potential to positively impact drilling effectiveness in deepwater and yield or save considerable value in these high cost operations
Microemulsion Technology for Synthetic-Based Mud Removal in Well Cementing Operations
Authors: Carrasquilla Juan , Guillot Dominique , Ali Syed A. , Nguyen Cecilia
Published: June 2012

Efficient displacement and effective removal of oil-based mud from the wellbore prior to cementing is critical to developing an excellent bond between casing and formation. Synthetic-based muds (SBM) can leave a thin-layer of oil on the casing and the formation when displacing to cement. It’s one of the least compatible fluids with cement slurries. This oil-layer can prevent the cement slurry from forming a strong bond with the formation and the casing. The lack of good bond could lead to poor zonal isolation and leave the casing and wellbore with decreased structural integrity. Removing this oily layer is generally accomplished by running viscosified weighted spacer containing cleaning agents ahead of cement slurry. Traditional surfactants have limited performance inverting and cleaning oil-water emulsions, besides being extremely detrimental for the development of the mechanical properties of the cement.

Microemulsions (Picture 4) are an oil-external, thermodynamically stable microemulsion that can be added in water or a viscous spacer as a single additive. The additive is a microemulsion dispersion of solvents and surfactants designed to enhance compatibility with the drilling fluid, demulsify, clean and water-wet the casing and borehole surfaces for better cement adhesion. Unlike traditional surfactants and solvents utilized to improve mud removal, the proprietary microemulsion additive, provides micellular dispersions that remain uniformly dispersed in water or viscous spacers, providing greater mud removal efficiency. Laboratory data demonstrates the effectiveness of the microemulsion in removing oil or synthetic-based mud while aggressively removing the oily layer and water-wetting from the casing and the formation.
A Wellbore Stability Approach For Self-Killing Blowout Assessment
Authors: Willson Stephen M.
Published: June 2012

An analysis approach to assess borehole stability following a hypothetical blowout from representative deepwater scenarios is presented. It addresses whether imposed underbalanced conditions cause sufficient instability that the borehole bridges-over and the well kills itself. The approach uses a series of interrelated analyses: (i) analyses of the kick and blowout development are performed predicting how bottom pressure and in-flow velocity changes over time; (ii) underbalanced wellbore failure in exposed shales and sands is then determined; (iii) cavings and produced sand volumes are calculated from the estimated failure zone, and the transport of these materials in the borehole is determined from the predicted hydrocarbon flow rates; and (iv) bridging tendency is assessed by considering the concentration of cavings in either the enlarged borehole or in flow-paths within the well casing or annuli.

To the best knowledge of the author, the proposed analysis presents the first in-depth study of transient wellbore instability, sand / cavings transport and bridging tendency during a blowout. Analyses applied to a typical deepwater blowout scenario suggest that bridging leading to self-killing can occur only in a small number of situations. This differs from the more widely published data from shallow water Gulf of Mexico Shelf wells which show that self-killing is likely in shallow-hazard scenarios.

Important conclusions from the study are: (1) bridging and self-killing can occur in kicks resulting from a catastrophic loss of riser integrity, due to the loss of the riser margin causing underbalanced conditions in openhole sections of the borehole; and (2) bridging and self-killing is more likely to occur in a well control event that develops while drilling-ahead, due to plugging of the borehole/drill-pipe annulus. Bridging is less likely to occur if a kick develops with the drill-pipe not in the open-hole interval. For self-killing to happen this study concludes that it has to occur during the time that the kick is developing – i.e. before hydrocarbons reach the wellhead. Once the kick has fully developed into a blowout it is predicted that typical high productivity deepwater reservoirs will have attained sufficient borehole flow velocity (in the absence of major constrictions to flow) that spalled or produced formations will be transported from the wellbore without bridging. Once a blowout has occurred, therefore, it is largely too late to consider future bridging as a means of terminating the flow, at least in the short-term.
Well Planning: A Risk Management Process
Authors: McManus Charles Dudley , Leach Patrick , Wicker Paul , Anderson Steve
Published: June 2012

Technology limits are continuously being pushed to meet the challenge of the ever increasing demand to drill deeper wells in deeper water. At the same time, the costs, time frame and risks have increased dramatically for such drilling projects, with the drilling and completion spread rates exceeding a million dollars per day. Errors in costs and timing have significant impact on project economics. How do you estimate the cost and timing appropriately and manage the risk? What are the potential trouble spots and how do you develop contingency plans? While drilling, which issues pose the greatest threat to project success? Are there new drilling and completion technologies or tools that can help mitigate the risks?

Drilling professionals have a wealth of experience in deepwater as well as the more traditional region of depth and reach that provides an intuitive framework and rich data set for probability assessments of what they may encounter. By appropriately tapping this data base of expertise and knowledge and using proven risk analysis techniques, teams can work through issues and gain better understanding of objectives, risks and uncertainties. Armed with these insights the team can frequently mitigate risks and move forward making more confident decisions.

This paper discusses a proven six step drilling solution and risk management approach. Structuring and analyzing a drilling project with this approach provides a robust assessment of the ultimate project economics. In addition, the team will gain non-intuitive insights, which enable them to make more informed decisions and develop effective risk management plans.
Development of an Improved FLC Pill for Testing Wire Wrap Screens Collapse and Burst Resistance
Authors: Gillespie George , Hall Christopher A. , Sladic John S
Published: June 2012

In August 2009, ISO Sand Screen Standard 17824 was approved for use. Subsequent qualification testing for burst and collapse resistance of wire wrap screens(WWS) by the service companies (SC) indicated there were inconsistent test results with using the formulated pill required by the new standard. In early 2011, revision 1 to 17824 was initiated to address this problem.

For deepwater completions, a high strength sand screen is often necessary to withstand the pressures when a FLC pill is applied to seal the well. The FLC pill needs to be a special formulation to insure the bridging agents can seal at applied burst pressures exceeding 2500 psi.

A service company reported that there were significant changes in the percentages of over, near, and under size of FLC pill residue taken from tested screens. The oversize material had been reduced by 35%, and the near size had been reduced about 20%. This indicated the bridging agents in the pill may be too weak to bridge properly at elevated pressures. Four different bridging agents, consisting of fifteen different formulations, were evaluated for crush resistance, subjected to different lab tests to evaluate their ability to seal the screen effectively with minimal leak off, and to maintain this seal at high applied pressures. Tests were done to verify the pill can be lifted off the screen with minimal pressure. It is planned that the two most promising formulations will then be subjected to full scale collapse and burst testing to verify that the high strength FLC pill will provide consistent test results for wire wrap screens.

The goal of the modified FLC pill formulation is that the FLC pill remains stable and provides an effective seal until the applied pressure results in sufficient changes in the dimensions and slot of the WWS causing loss of sand control. Ideally, the burst and collapse resistance should approach the mechanical failure of the wire wrap screen being used. The FLC pill needs a different formulation to insure the bridging agents can also seal at applied burst pressures exceeding 2500 psi. Several successful completions have been reported using a special FLC pill with a very heavy wire wrap screen design. The results of the improved FLC pill testing will likely have an impact on wire wrap screen ratings for deep water completions.
Drinking water standards in South American countries: convergences and divergences
Authors: Pinto Vívian Gemiliano , Heller Léo , Bastos Rafael Kopschitz Xavier
Published: June 2012

In this paper we present a comparative assessment of drinking-water standards from almost all South American countries, using the USA and the Canadian standards and the World Health Organization (WHO) Guidelines as references. Similarities and discrepancies between standards/guidelines were identified through descriptive analyses and, in the case of chemical standards, clustering techniques. In general, one or another of the four consecutive editions of the WHO Guidelines were shown to be quite influential in setting drinking-water standards in the region, but not so much the USA and the Canadian standards. Considerable discrepancies between South American drinking-water standards were found, mainly with respect to chemical substances. Questions are raised about their scientific basis and/or the practicalities for their enforcement. In conclusion, the paper highlights that many drinking-water regulations in South America need updating, taking on the approach of health-based targets in setting these standards, as well as that of a broader risk-based preventive management in the entire supply system to assure water safety.
Sanitary inspection of wells using risk-of-contamination scoring indicates a high predictive ability for bacterial faecal pollution in the peri-urban tropical lowlands of Dar es Salaam, Tanzania
Authors: Mushi Douglas , Byamukama Denis , Kirschner Alexander K.T. , Mach Robert L. , Brunner K. , Farnleitner Andreas H.
Published: June 2012

Sanitary inspection of wells was performed according to World Health Organization (WHO) procedures using risk-of-contamination (ROC) scoring in the peri-urban tropical lowlands of Dar es Salaam, Tanzania. The ROC was assessed for its capacity to predict bacterial faecal pollution in the investigated well water. The analysis was based on a selection of wells representing environments with low to high presumptive faecal pollution risk and a multi-parametric data set of bacterial indicators, generating a comprehensive picture of the level and characteristics of faecal pollution (such as vegetative Escherichia coli cells, Clostridium perfringens spores and human-associated sorbitol fermenting Bifidobacteria). ROC scoring demonstrated a remarkable ability to predict bacterial faecal pollution levels in the investigated well water (e.g. 87% of E. coli concentration variations were predicted by ROC scoring). Physicochemical characteristics of the wells were not reflected by the ROC scores. Our results indicate that ROC scoring is a useful tool for supporting health-related well water management in urban and suburban areas of tropical, developing countries. The outcome of this study is discussed in the context of previously published results, and future directions are suggested.
Molecular cloning of Brevundimonas diminuta for efficacy assessment of reverse osmosis devices
Authors: Donofrio Robert , Saha Ratul , Bestervelt Lori , Bagley Susan
Published: June 2012

Brevundimonas diminuta is the test organism specified in the United States Environmental Protection Agency's (USEPA) reverse osmosis (RO) treatment device verification protocol. As non-selective growth medium is employed, enumeration of B. diminuta may be impaired due to interference by indigenous heterotrophic bacteria. Thus the microbial removal capability of the filtration system may be incorrectly assessed. As these treatment devices are used in emergency situations, the health of the public could be compromised. The objective of this study was to develop selective approaches for enumerating viable B. diminuta in test water. Two molecular approaches were investigated: expression of a kanamycin resistance gene and expression of a fluorescent protein gene. The USEPA protocol specifies a 0.3 μm cell size, so the expression of the selective markers were assessed following growth on media designed to induce this small cell diameter. The kanR strain was demonstrated to be equivalent to the wild type in cell dimension and survival following exposure to the test water. The kanR strain showed equivalent performance to the wild type in the RO protocol indicating that it is a viable alternative surrogate. By utilizing this strain, a more accurate validation of the RO system can be achieved.
Association of plasmid-mediated quinolone resistance and virulence markers in Escherichia coli isolated from water
Authors: Mendonça Nuno , Ramalho Joana , Vieira Pedro , Da Silva Gabriela Jorge
Published: June 2012

This work aimed to investigate the association of the carriage of plasmid-mediated quinolone resistance (PMQR) genes, the virulence potential encoded in pathogenicity islands (PAIs) and the phylogenetic background in Escherichia coli strains isolated from waters of diverse origin. Antimicrobial susceptibilities were determined by the disc diffusion method. Screening for PMQR (qnr, aac(6′)-Ib-variant and qepA) genes, PAIs and the determination of phylogroup was performed by PCR. Nineteen percent of strains were resistant to nalidixic acid, 11% to ciprofloxacin and 5% to gentamicin. qnrA was the only PMQR detected in 16% of strains, susceptible to quinolones and grouped in phylogenetic lineage B1. Sixty-seven percent of the isolates were assigned to the less-virulent groups A and B1. PAIs IV536 and IICFT073 were detected in 16 and 3% of the isolates, respectively. All PAIs were detected in the phylogroups D and B1. The presence of PAIs in isolates from waters may represent an increased risk for public health, as they were isolated from samples collected from surface and drinking waters. As E. coli is an important indicator of microbiological water quality, and also a potential pathogen, routine analysis for its detection could be complemented by screening for virulence factors and antimicrobial genes.
The effect of UV-C radiation (254 nm) on candidate microbial source tracking phages infecting a human-specific strain of Bacteroides fragilis (GB-124)
Authors: Diston D. , Ebdon J. E. , Taylor H. D.
Published: June 2012

The enumeration of phages infecting host-specific strains of Bacteroides has been widely recognised as an effective and low-cost method of microbial source tracking (MST). A recently described human-specific Bacteroides host strain (GB-124) has been shown to detect bacteriophages exclusively in human-impacted waters and is emerging as a useful MST tool. However, a better understanding of the morphology and ecological behaviour of the phages, especially in wastewater disinfection processes, is now required in order to validate their role as MST markers. Bacteriophages infecting Bacteroides fragilis GB-124 (n = 21) were isolated from wastewater effluent and irradiated using laboratory-based UV-C (254 nm) collimated beam experiments. Bacteriophages were found to be both a morphologically and ecologically homogeneous group, with all specimens showing highly similar first order log-linear inactivation profiles (mean fluence required to inactivate phages by 4-log10 was 36 mJ/cm2). These findings present the first evidence that phages infecting GB-124 are inactivated by the levels of UV-C radiation routinely delivered during tertiary wastewater treatment processes. More importantly, comparison with previously published inactivation data suggests that their response to UV-C radiation makes GB-124 phages more suitable surrogates for selected enteric viruses in UV disinfection processes than traditional faecal indicator bacteria or human-specific molecular markers.
The descriptive set-theoretic complexity of the set of points of continuity of a multi-valued function
Authors: Gregoriades Vassilios
Published: June 2012

In this article we treat a notion of continuity for a multi-valued function
$F$ and we compute the descriptive set-theoretic complexity of the set of all
$x$ for which $F$ is continuous at $x$. We give conditions under which the
latter set is either a $G_\delta$ set or the countable union of $G_\delta$
sets. Also we provide a counterexample which shows that the latter result is
optimum under the same conditions. Moreover we prove that those conditions are
necessary in order to obtain that the set of points of continuity of $F$ is
Borel i.e., we show that if we drop some of the previous conditions then there
is a multi-valued function $F$ whose graph is a Borel set and the set of points
of continuity of $F$ is not a Borel set. Finally we give some analogous results
regarding a stronger notion of continuity for a multi-valued function. This
article is motivated by a question of M. Ziegler in [{\em Real Computation with
Least Discrete Advice: A Complexity Theory of Nonuniform Computability with
Applications to Linear Algebra}, {\sl submitted}].
A decidable characterization of locally testable tree languages
Authors: Place Thomas , Segoufin Luc
Published: June 2012

A regular tree language L is locally testable if membership of a tree in L
depends only on the presence or absence of some fix set of neighborhoods in the
tree. In this paper we show that it is decidable whether a regular tree
language is locally testable. The decidability is shown for ranked trees and
for unranked unordered trees.
The Complexity of Rooted Phylogeny Problems
Authors: Bodirsky Manuel , Mueller Jens K
Published: June 2012

Several computational problems in phylogenetic reconstruction can be
formulated as restrictions of the following general problem: given a formula in
conjunctive normal form where the literals are rooted triples, is there a
rooted binary tree that satisfies the formula? If the formulas do not contain
disjunctions, the problem becomes the famous rooted triple consistency problem,
which can be solved in polynomial time by an algorithm of Aho, Sagiv,
Szymanski, and Ullman. If the clauses in the formulas are restricted to
disjunctions of negated triples, Ng, Steel, and Wormald showed that the problem
remains NP-complete. We systematically study the computational complexity of
the problem for all such restrictions of the clauses in the input formula. For
certain restricted disjunctions of triples we present an algorithm that has
sub-quadratic running time and is asymptotically as fast as the fastest known
algorithm for the rooted triple consistency problem. We also show that any
restriction of the general rooted phylogeny problem that does not fall into our
tractable class is NP-complete, using known results about the complexity of
Boolean constraint satisfaction problems. Finally, we present a pebble game
argument that shows that the rooted triple consistency problem (and also all
generalizations studied in this paper) cannot be solved by Datalog.
Complexity of Model Checking Recursion Schemes for Fragments of the Modal Mu-Calculus
Authors: Kobayashi Naoki , Ong C. -H. Luke
Published: June 2012

Ong has shown that the modal mu-calculus model checking problem
(equivalently, the alternating parity tree automaton (APT) acceptance problem)
of possibly-infinite ranked trees generated by order-n recursion schemes is
n-EXPTIME complete. We consider two subclasses of APT and investigate the
complexity of the respective acceptance problems. The main results are that,
for APT with a single priority, the problem is still n-EXPTIME complete;
whereas, for APT with a disjunctive transition function, the problem is
(n-1)-EXPTIME complete. This study was motivated by Kobayashi's recent work
showing that the resource usage verification of functional programs can be
reduced to the model checking of recursion schemes. As an application, we show
that the resource usage verification problem is (n-1)-EXPTIME complete.
Fusion frames and g-frames in tensor product and direct sum of Hilbert spaces
Authors: Khosravi Amir , Mirzaee Azandaryani
Published: June 2012

In this paper we study fusion frames and g-frames for the tensor products and
direct sums of Hilbert spaces. We show that the tensor product of a finite
number of g-frames (resp. fusion frames, g-Riesz bases) is a g-frame (resp.
fusion frame, g-Riesz basis) for the tensor product space and vice versa.
Moreover we obtain some important results in tensor products and direct sums
of g-frames, fusion frames, resolutions of the identity and duals.
Introductory Accounting, with Matrices, at the Southern Federal University, Russia
Authors: Stoner Gregory N. , Vysotskaya Anna
Published: June 2012

Within the context of the globalization of the practice and profession of accounting, it is increasingly important that accounting faculty and students are aware of the international accounting environment. In addition, the continued growth in the cross-national flows of students increases the need for accounting faculty to be aware of international differences in the teaching and learning of accounting. This paper contributes to this arena by looking at the context, structure, and content of a successful introductory accounting course at a major university in the Russian Federation that uses matrix accounting theory in its introductory accounting course. By doing so, the paper provides accounting educators with a range of insights into the diversity of the international context of the teaching of accounting, and provides awareness of the theory of matrix accounting and how and why this mathematical approach to the teaching of introductory accounting has been adopted. In addition, as part of the important \contextual background, the paper provides a rich description of the course, which could be used for comparison with other introductory accounting courses.

By looking at introductory accounting from a different perspective, the paper has the potential to help and encourage accounting faculty to think afresh about our discipline by questioning some of the taken-for-granted assumptions that underlie the approaches used in teaching accounting.
Occlusal hypofunction causes periodontal atrophy and VEGF/VEGFR inhibition in tooth movement
Authors: Usumi-Fujita Risa , Hosomichi Jun , Ono Noriaki , Shibutani Naoki , Kaneko Sawa , Shimizu Yasuhiro , Ono Takashi
Published: June 2012

Objective:

To examine changes in microvasculature and the expression of vascular endothelial growth factor A (VEGF-A) and VEGF receptor 2 (VEGFR-2) in rat hypofunctional periodontal ligament (PDL) during experimental tooth movement.

Materials and Methods:

Twelve-week-old male Sprague-Dawley rats were divided into normal occlusion and occlusal hypofunction groups. After a 2-week bite-raising period, rat first molar was moved mesially using a 10-gf titanium-nickel alloy closed coil spring in both groups. On days 0, 1, 2, 3, and 7 after tooth movement, histologic changes were examined by micro–computed tomography and immunohistochemistry using CD31, VEGF-A, VEGFR-2, and the terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method.

Results:

Hypofunctional molars inclined more than normal molars and did not move notably after day 1 of tooth movement. Blood vessels increased on the tension side of the PDL in normal teeth. Immunoreactivities for VEGF-A and VEGFR-2 in normal teeth were greater than those in hypofunctional teeth during tooth movement. Compressive force rapidly caused apoptosis of the PDL and vascular endothelial cells in hypofunctional teeth, but not in normal teeth.

Conclusions:

Occlusal hypofunction induces vascular constriction through a decrease in the expression of VEGF-A and VEGFR-2, and apoptosis of the PDL and vascular cells occurs during tooth movement.
Evaluation of Herbicide-Resistance Status on Populations of Littleseed Canarygrass (Phalaris Minor Retz.) from Southern Greece and Suggestions for their Effective Control
Authors: Travlos Ilias
Published: June 2012

Evaluation of Herbicide-Resistance Status on Populations of Littleseed Canarygrass (Phalaris MinorRetz.) from Southern Greece and Suggestions for their Effective Control

In 2010, a survey was conducted in the wheat fields of a typical cereal-producing region of Greece to establish the frequency and distribution of herbicide-resistant littleseed canarygrass (Phalaris minorRetz.). In total, 73 canarygrass accessions were collected and screened in a field experiment with several herbicides commonly used to control this weed. Most of the weed populations were classed as resistant (or developing resistance) to the acetyl-CoA varboxylase (ACCase)-inhibiting herbicide diclofop, while resistance to clodinafop was markedly lower. The results of the pot experiments showed that some of the canary populations were found to have a very high level of diclofop resistance (resistance index up to 12.4), while cross resistance with other herbicides was also common. The levels of resistance and cross resistance patterns among populations varied along with the different amounts and times of selection pressure. Such variation indicated either more than one mechanism of resistance or different resistance mutations in these weed populations. The population which had the highest diclofop resistance level, showed resistance to all aryloxyphenoxypropinate (APP) herbicides applied and non-ACCase inhibitors. Alternative ACCase-inhibiting herbicides, such as pinoxaden remain effective on the majority of the tested canarygrass populations, while the acetolactate synthase (ALS)-inhibiting herbicide mesosulfuron + iodosulfuron could also provide some solutions. Consequently, there is an opportunity to effectively control canarygrass by selecting from a wide range of herbicides. It is the integration of agronomic practices with herbicide application, which helps in effective management ofP. minorand particularly its resistant populations.
Effect of Different Constant Temperatures on Biology of Schizaphis Graminum (Rondani) (Hemiptera: Aphididae) on Barley, Hordeum Vulgare L. (Poaceae) in Iran
Authors: Tofangsazi Nastaran , Kheradmand Katayoon , Shahrokhi Shahram , Talebi Ali
Published: June 2012

Effect of Different Constant Temperatures on Biology ofSchizaphis Graminum(Rondani) (Hemiptera: Aphididae) on Barley,Hordeum VulgareL. (Poaceae) in Iran

The temperature dependent biology of greenbug,Schizaphis graminumRondani on Kavir barley cultivar was studied at seven constant temperatures including 10, 15, 19, 22, 26, 31, and 33±1°C, 70% relative humidity (RH), and a photoperiod of 16:8 (L:D) hours. The period of immature development ranged between 6.60 days at 26°C to 28.56 days at 10°C, respectively. All tested aphids failed to develop at 33°C. The calculatedrmand λ values were significantly the highest at 26°C and lowest at 10°C, respectively. The mean generation time and doubling time ofS. graminumdecreased linearly by increasing the temperature from 10 to 26°C. Additionally, the total number of offsprings per female was extremely low at 10 and 31°C, contrary to the highest and lowest values of life expectancy at 10°C (41.73 days) and 31°C (7.66 days), respectively. The results of the present study revealed that temperature had great effects on biology ofS. graminum, which was never previously studied on barley in Iran.
Change in Life Expectancy and Stable Age Distribution of the Diamondback Moth, Plutella Xylostella (L.) After Indoxacarb Treatment
Authors: Mahmoudvand Mohammad , Abbasipour Habib , Garjan Aziz , Bandani Ali
Published: June 2012

Change in Life Expectancy and Stable Age Distribution of the Diamondback Moth,Plutella Xylostella(L.) After Indoxacarb Treatment

Using high doses of insecticides is very dangerous for the environments and for humans. Decreased concentrations are necessary. Insecticides have lethal and sublethal effects. The aim of the present study was to determine the behavior ofPlutella xylostellawhen exposed to sublethal doses of indoxacarb in terms of the age-specific fecundity (mx), life expectancy (ex) and stable age distribution (Cx). Also, the effects of sublethals on the pre-oviposition, oviposition and post-oviposition period of this insect were investigated. The results show that exposure to this insecticide decreased the age-specific fecundity (mx) and life expectancy (ex) of the insect. Although the pre-oviposition period was delayed in the treated groups, the post-oviposition period significantly decreased when exposed to LC10and LC25doses (the dose concentrations killed 10 and 25% of the populations) of indoxacarb. The oviposition period did not change. Furthermore, sublethal concentrations of the applied insecticide caused changes in the exposed structure.
How liberal is Estonian alcohol policy? A review of policy development, 1991–2008
Authors: Kollom Kersti
Published: June 2012

Aims

This article inspects alcohol policy changes in Estonia between 1991 and 2008, using the Eurocare Bridging the Gap (BtG) scale. Estonian indicators are compared with those of 30 European countries. Seven alcohol policy measures are discussed: control of production and wholesale; control of distribution; age limits; advertising; social and environmental control; public policy; and alcohol taxation.

Data

The indicator values are based on an analysis of legislative changes and governmental programmes during these years.

Results

Alcohol policy issues have had low political priority in independent Estonia. In international comparison, the initial policy of the early 1990s was extremely liberal. The most intensive period of political and economic reforms started to subside after 1995, alcohol legislation was overhauled in 1998–1999 and unified restrictions on sales hours were introduced in 2008, all of which led to receding liberalism. The contrast to the neighbouring Nordic countries nevertheless remains sharp. In relation to other European countries, Estonian alcohol controls remain at a medium level.

Conclusions

In line with an improved administrative capacity, Estonia has implemented more structured alcohol policies, which also take social aspects into consideration.
Orphan drugs used for treatment in pediatric patients in the slovak republic
Authors: Foltánová T. , Konečný M. , Hlavatá A. , Štepánková K. , Cisárik F.
Published: June 2012

Orphan drugs used for treatment in pediatric patients in the slovak republic

Due to the enormous success of scientific research in the field of paediatric medicine many once fatal children's diseases can now be cured. Great progress has also been achieved in the rehabilitation of disabilities. However, there is still a big group of diseases defined as rare, treatment of which has been traditionally neglected by the drug companies mainly due to unprofitability.

Since 2000 the treatment of rare diseases has been supported at the European level and in 2007 paediatric legislation was introduced. Both decisions together support treatment of rare diseases in children.

In this paper, we shortly characterise the possibilities of rare diseases treatment in children in the Slovak republic and bring the list of orphan medicine products (OMPs) with defined dosing in paediatrics, which were launched in the Slovak market. We also bring a list of OMPs with defined dosing in children, which are not available in the national market. This incentive may help in further formation of the national plan for treating rare diseases as well as improvement in treatment options and availability of rare disease treatment in children in Slovakia.
The problem of low peak concentration of gentamicin in clinical practice
Authors: Göböová M. , Kuželová M. , Foltánová T.
Published: June 2012

The problem of low peak concentration of gentamicin in clinical practice

Aminoglycoside antibiotics have particular importance in the treatment of Gram-negative infections. Toxicity of gentamicin is well-known, but patients often receive insufficient dosage in clinical practice. The purpose of this study was to refer to the problem of insufficient dosages that were confirmed by low peak concentration and to determine relationship between low peak levels and pharmacokinetic parameters, renal function and body weight.

We studied 68 patients who were treated with gentamicin for one year (August 2010 - August 2011). Therapeutic drug monitoring (TDM) was applied for all the patients. Gentamicin peak and trough concentrations were measured by the FPIA (Fluorescence Polarization Immunoassay) method with an analyser, AxSYM of ABBOTT company. We divided the patients into 3 groups according to peak and trough levels.

Together 13 (19%) patients had high trough concentrations and optimal peak concentrations. Only 6 (9%) patients had optimal trough and peak levels in the first measurement of plasma concentrations. The third group included 49 patients (72%). These patients had optimal trough levels and low peak levels in the first measurement. 34 patients of the third group (28 males, 6 females) had optimal peak levels after adjustment of dosage in the second measurement. 15 patients, only males did not reach optimal peak levels even after adjustment of dosage in the second measurement.

The patients with low peak levels of gentamicin are more frequent than patients with toxic adverse effects in clinical practice. Especially, these are the patients with higher value of body weight and following increased pharmacokinetic parameters: creatinine clearance, total volume of distribution, total clearance and elimination rate constant. The clinical pharmacists have to adjust dosage regimens, especially according to Therapeutic drug monitoring (TDM) and clinical experience. The results of the study have confirmed that the clinical pharmacists must adjust dose regimen not only for patients who require reduced doses but more often for patients who require higher doses than are commonly used in clinical practice. These patients are at risk of underdosing of aminoglycoside antibiotics.
Analysis of acute clonazepam intoxications during the ten-year period 2001 - 2010
Authors: Ondriašová E. , Knietlová E. , Cagáňová B. , Kuželová M. , Plačková S.
Published: June 2012

Analysis of acute clonazepam intoxications during the ten-year period 2001 - 2010

In the article acute intoxications by clonazepam (Rivotril) consulted with the National Toxicological Information Centre (NTIC) in Bratislava during the years 2001 - 2010 are analysed. 431 records of acute clonazepam intoxications were evaluated according to gender, age, cause, poisoning severity score and therapy. 57% of all patients were female, 42% were male. The highest number, 123, was in the age between 19 - 35 years and 117 between 36 - 50 years, and most of these cases were suicidal attempts (85% and 90%). Accidental poisoning was most common in children under 5 years of age (65 cases). In the age over 65 years were 4 cases. 69% of all evaluated intoxications were suicidal and 18% were accidental. 61% of intoxications were combined, particularly with alcohol and antidepressant, anxiolytic and antiepileptic drugs. The most common poisoning severity score (68% cases) was PSS 1, which means intoxications accompanied by mild, transient and spontaneously resolving symptoms - fatigue, somnolence, ataxia. There were five lethal cases (PSS 4) as the consequence of combined drug intoxications with suicidal intent. Complete data about therapeutical treatment were obtained for 114 patients. In most cases, hospital treatment was non-specific decontamination and supportive symptomatic therapy. 97 patients received activated charcoal, 55 activated charcoal with laxative, 38 gastric lavage and 12 patients were given the specific antidote flumazenil (Anexate).

By retrospective analysis, we found an increasing tendency of clonazepam intoxications mainly suicidal.

In spite of the fact that it is mandatory to report intoxications to the NTIC in the form of a copy of the medical record of each patient hospitalized due to intoxication, there are still medical facilities which don't fulfil this requirement. If all the medical records were available, it would lead to more precise knowledge about intoxications in Slovakia and a better possibility for introducing measures to lower the number and consequences of intoxication.
Better medicines for children: challenges and unmet needs
Authors: Slažneva J. , Kákošová V. , Kuželová M.
Published: June 2012

Better medicines for children: challenges and unmet needs

This review deals with the use of medicinal products in children. Many medicinal products administered routinely to paediatric patients have been either not licensed for use in children (unlicensed use) or have been prescribed outside the terms of their product license (off-label prescribing). A lot of surveys have been conducted in the context of identifying the extent of off-label used drugs in children documenting high rates (45-60 %) of such use. Recognising and meeting challenges as development of suitable formulations for very young children and realization of clinical trials involving children present important steps in the enhancement of the present situation. To improve the health of children in Europe, the Regulation (EC) No 1901/2006 addressing the pharmaceutical industry, research teams and member states proposing important incentives and obligations was assigned. Paediatric Investigation Plan and Paediatric Use Marketing Authorisation present the key measures of the EU regulation on medicinal products for paediatric patients.
Pharmacotherapeutic adherence and quality of life in paediatric outpatients with epilepsy
Authors: Virág Ľ. , Murgaš M. , Kuželová M.
Published: June 2012

Pharmacotherapeutic adherence and quality of life in paediatric outpatients with epilepsy

The aim of this study was to obtain data about pharmacotherapeutic adherence, quality of life and its relations in paediatric outpatients.

The present survey was conducted at the Outpatient Department of Paediatric Neurology in Nitra. QOLIE-AD-48 questionnaire was used to assess quality of life and pharmacotherapeutic adherence prospectively. Ninety five patients met the inclusion criteria. The study was approved by the Ethics Committee of the Faculty of Pharmacy, Comenius University in Bratislava.

Questionnaires were returned by 74 (77.9%) paediatric patients. The mean quality of life score was 75.2. The quality of life score was lower in children who had higher seizure frequency, were medicated by polytherapy, who experienced adverse effects, with lower age during first seizure, with stigma, and also in those who experienced non-adherence. Adherence was poor in 15 (20.3%) patients. Non-adherence was significantly more frequent in patients 14-18 years old, in those with insufficient seizure control, in those with adverse effects, and also in patients with lower quality of life (p<0.05).

Non-adherence with medication was detected in practically 30% of our adolescents. Therefore, assessing medication adherence and counseling patients about it should be important components of daily clinical practice mainly in risk patients.
Editoral
Authors: Tatiana Foltánová
Published: June 2012

Editoral
Mobile Phone Accidents - Experience Of India
Authors: Shabeer H. , Banu Wahida
Published: June 2012

Mobile Phone Accidents - Experience Of India

Every year nearly 1.4 million people have been killed because of they are wireless customers and their over-bearing cell phones. While in India, an estimated 1.35 lakhs person died due to road accident in 2010, which is approximately 10% of road accident fatalities worldwide and these figures are the highest in the world. But still no research has been carried out to find the number of drivers using cell phone involved in road accident and very limited efforts has been carried out to prevent accident due to cell phone usage. To our knowledge this is the first survey carried out in India to determine the number of drivers involved in an accident due to mobile phone use. With the aim of preventing such accidents, it is proposed to develop a highly efficient automatic system for early detection of incoming and outgoing call, by placing an antenna along with mobile detection unit above the driver seat. This unit is capable of distinguishing whether the cell phone used either by the driver or by the passenger, if the driver uses of cell phone is detected, a safety application named Cellphone Accident Preventer (C.A.P.) which is developed using J2ME will be automatically load on the driver's cell phone which helps in eliminating the risk of accidents from occurring, at the same time ensuring that the user does not miss any emergency call. The research has been extended to show how far the system will help in preventing accidents and to what extent this system will help in reducing the Indian economic loss incurred unnecessarily due to road accident fatalities.