bluuebunny/crossref_metadata_2025_split huggingface dataset:
Implementing a Multipurpose Tool Solution to Successfully Stimulate an Extended Reach Horizontal Power Water Injector
Authors: Eissa M. A. , Mehmood S. , Jassem H. M. , Barkat S. , Bal M. , Rivadeneira E. V. , Bragaw T. , O'Neal E. 
Published: February 2016

Abstract
As a result of the continuous development of drilling technology, more complex wells can be drilled to overcome reservoir challenges and reach target intervals. Over the last decade, innovative drilling techniques have enabled a significant increase in the number of multilaterals and extended-reach wells; this imposes new challenges regarding well accessibility for rigless intervention techniques, which has driven operators, manufacturing, and service companies to develop innovative strategies for servicing these fields.
In Saudi Arabia, one extended-reach power water injector (PWI) well was sidetracked to enhance injectivity. During the sidetrack, it was necessary to drill more than 1,000-psi overbalance due to the presence of high-pressure zones across the horizontal section, which resulted in formation damage on the low-pressure intervals. Based on this situation, a well intervention plan was considered which would use Coiled Tubing (CT) acid stimulation to remove the formation damage especially toward the end of the open-hole horizontal section.
This operation involved two particular challenges; the first of which was the CT reach across the open-hole section, especially when CT forces simulation predicted a maximum coverage of 50% of the target zone. The second challenge was implementing the proper jetting tool to be able to function with the combination of the downhole tractor and high rate acid stimulation to ensure penetration across the filter cake and remove formation damage in the entire target zone. In order to make this solution feasible a specially designed downhole tractor was engineered, manufactured and incorporated with a newly designed high pressure jetting tool to be able to have full functionality of the downhole tractor while still performing full high rate stimulation to penetrate the damaged zones.
This paper describes the combination of slim tractor and high-pressure jetting tool to conduct an effective acid stimulation job in an extended-reach PWI and have a CT reach of 98% instead of the predicted 50% reach in one of the major carbonate reservoirs in the Saudi Arabia. In addition, this paper provides design methodologies, best practices and industry lessons learnt from the experiences gained in the implementation of multi-purpose tool solution in Saudi Arabia.
First Use of Multiple Set and Release Barrier Plug Technology on E-Line
Authors: Langaker Hein Andre , Johansen Thomas Bergan , Robertsen Sveinung , Skretting Per Kristian 
Published: February 2016

Abstract
Wells that produce hydrocabons or provide injection into the reservoir may have a long life span and often require intervention, by wireline or coil tubing, in order to optimize the production rates and oil/water/gas ratio. Scenarios where the casing/tubing is deformed or contains depositions of materials like for example scale or sand provides a challenging environment for conventional plugs to seal and hold pressure.
This paper will provide insight into the field trial and development of a single run, multiple set barrier plug technology that was designed to mitigate the risks associated with conventional plug operations.
The plug and electric manipulation tool (EMT) was run on wireline in a deviated production well with gas lift and set at three different depths to verify the location of a leak and elimate that the leak was in the one of the side pocket mandrels (SPM). All of the operational features of the technology was tested on this one run, including the selective equalization method and the ability to latch on and off with the running tool.
In its first use the technology successfully verified that the leak was not in the SPMs and provided reliable data that shows that the ability to set and reposition a barrier multiple time can be useful in many applications as it improves operational efficiency and safety while at the same time reducing risk.
Effects of Perforated Flow Tube on the Flow Field of a Blowout Well
Authors: Hajidavalloo Ebrahim , Dehkohneh Saeed Alidadi 
Published: February 2016

Summary
When a blowout oil/gas well catches fire, usually a flow tube is used to detach the fire from the wellhead and provide appropriate conditions for operating team members to approach the well and install the blowout-preventer (BOP) cap. Using the flow tube above the wellhead creates powerful suction around the tube that may jeopardize the safety of crew members. To reduce the power of suction around the well, a new perforated flow tube instead of simple flow tube was introduced. To understand the effect of this new type of flow tube, modeling and simulation of the flow field around the blowout well were performed for both simple and perforated types of flow tube with Fluent 6.3.26 (2003) and Gambit 2.3.16 (2003) softwares. Different parameters around the well mouth were compared in both designs. The results showed that using the perforated flow tube decreases the vacuum around the well by 33% compared with the simple flow tubes. Thus, application of the perforated flow tube can be recommended in well-control operations for safety measures.
Is Anti-Müllerian Hormone Associated with IVF Outcomes in Young Patients with Diminished Ovarian Reserve?
Authors: Pereira Nigel , Setton Robert , Petrini Allison C , Lekovich Jovana P , Elias Rony T , Spandorfer Steven D 
Published: February 2016

Aim: To investigate whether anti-Müllerian hormone (AMH) is associated with IVF cycle outcomes in young patients with diminished ovarian reserve. Materials & methods: Retrospective study of patients <35 years of age undergoing fresh IVF who had at least two 8-cell, day-3 embryos transferred with grades 1, 1.5 or 2. Patients were subgrouped, a priori, based on serum AMH levels: <1 or >1 ng/ml and <0.5 or >0.5 ng/ml. Results: In total, 1005 patients were included. Patients in the >1 ng/ml group required lesser gonadotropins compared with the <1 ng/ml and the <0.5 ng/ml group. More oocytes were retrieved from the same group compared with the latter two (p < 0.001). Despite these differences, the overall rates of clinical pregnancy, spontaneous abortion and live birth were comparable between the two groups. Conclusion: In patients with diminished ovarian reserve who have good quality embryos, AMH is not associated with clinical pregnancy, spontaneous miscarriage or live birth rates.
Are interest groups different in the factors determining landscape preferences?
Authors: Bacher Maria , Walde Janette F. , Pecher Caroline , Tasser Erich , Tappeiner Ulrike 
Published: February 2016

In the last decades, rural landscape in Europe has evolved from an agricultural by-product to an important public good. This development creates not only new challenges to farming practices, it also makes participation and public involvement an indispensable tool for sustainable landscape planning. This is especially true for many European mountain regions, where tourism represents an important source of income and conflicts between locals’ and tourists’ interests should be avoided. In our study, we analyze whether discrepancies in the perception of the Alpine landscape can be located between locals and tourists and, if these differences exist, in which aspects these two groups are differing. A model employing three general factors able to describe landscape preferences regardless of the personal background is suggested and validated by confirmatory factor analysis. Our major finding shows that an attractive landscape for tourists does not have to be contradictory to a landscape that supports a high living quality for locals. Compromises in landscape planning between locals’ and tourists’ requirements seem often not to be necessary as they, generally, do not differ in the way they experience and assess the landscape.
Co-composting of organic solid waste and sewage sludge – a waste management option for University Campus
Authors: Fei-Baffoe Bernard , Osei Kenneth , Agyapong Eric Appiah , Nyankson Eugene Atta 
Published: February 2016

Co-composting organic solid waste with dewatered sewage sludge was carried out to determine its suitability for managing waste on a University campus. Windrow composting method was employed in which dewatered sewage sludge and organic solid waste were mixed at volume ratios: 1:1, 1:2, 1:3, 0:1 and 1:0 sludge/organic solid waste. Parameters such as pH, percentage N, C, P, K, Ca, Mg, organic matter, ash content and C/N ratio were determined weekly. Total and faecal coliform population were measured biweekly with Pb and Cd levels determined at the beginning and end of the composting. With the exception of ratio 1:0 sludge/organic solid waste, all other ratios attained a favourable Carbon to Nitrogen (C/N) ratio both at the start and end of the composting process. Levels of major nutrients measured were found to be favourable for use as organic fertilizer. There was a general decline in carbon and organic matter in all the compost piles except the sewage sludge pile (1:0). Apart from the compost ratio 1:0 sludge/organic solid waste, all other ratios attained a temperature of 55°C within 8 days of composting. Generally the compost ratios 1:2, 1:3 and 0:1 (sludge/organic solid waste) were found to be the most suitable for use as organic fertilizer. International Journal of Environment Vol. 5 (1) 2016, pp: 14-31
Impact of climatic variability on durum wheat (Triticum durum L.) yields in North Western of Algeria
Authors: Baroudi Meterfi , Zerey Wael El , Bouiadjra Salaheddine Bachir 
Published: February 2016

In semi arid region of the South West of the Mediterranean basin, low rainfall, and thermal fluctuations cause water stress situations affecting at different levels, with varying intensities, the development of durum wheat yields. This work aims to study the major climatic factors that determine water environment of durum wheat in its reproductive period and assess their trend related to yields of the grain. Comparing diagrams of Bagnoul and Gaussen, established for two periods (1913-1937 and 1977-2014), highlighted an increase in the duration of the dry season due to rising temperatures, especially summer and a decrease in volume of the seasonal rainfall involving therefore water stress during the reproductive phase of cereal. The analysis of water regime in the past three decades, for the months of March, April and May, through the application of the approach of UNESCO-FAO, highlighted a very large variability in intensity of water stress during grain development period during the last years and also the tendency of the spring season months to be more drought. This reflects the complexity of the selection for yield components in this region. International Journal of Environment Vol. 5 (1) 2016, pp: 107-120
Ammonia in the summertime Arctic marine boundary layer: sources, sinks, and implications
Authors: Wentworth Gregory R. , Murphy Jennifer G. , Croft Betty , Martin Randall V. , Pierce Jeffrey R. , Côté Jean-Sébastien , Courchesne Isabelle , Tremblay Jean-Éric , Gagnon Jonathan , Thomas Jennie L. , Sharma Sangeeta , Toom-Sauntry Desiree , Chivulescu Alina , Levasseur Maurice , Abbatt Jonathan P. D. 
Published: February 2016

Abstract. Continuous hourly measurements of gas-phase ammonia (NH3(g)) were taken from 13 July to 7 August 2014 on a research cruise throughout Baffin Bay and the eastern Canadian Arctic Archipelago. Concentrations ranged from 30 to 650 ng m−3 (40–870 pptv) with the highest values recorded in Lancaster Sound (74°13′ N, 84°00′ W). Simultaneous measurements of total ammonium ([NHx]), pH and temperature in the ocean and in melt ponds were used to compute the compensation point (χ), which is the ambient NH3(g) concentration at which surface–air fluxes change direction. Ambient NH3(g) was usually several orders of magnitude larger than both χocean and χMP (< 0.4–10 ng m3) indicating these surface pools are net sinks of NH3. Flux calculations estimate average net downward fluxes of 1.4 and 1.1 ng m−2 s−1 for the open ocean and melt ponds, respectively. Sufficient NH3(g) was present to neutralize non-sea-salt sulfate (nss-SO42−) in the boundary layer during most of the study. This finding was corroborated with a historical data set of PM2.5 composition from Alert, Nunavut (82°30′ N, 62°20′ W) wherein the median ratio of NH4+/nss-SO42− equivalents was greater than 0.75 in June, July and August. The GEOS-Chem chemical transport model was employed to examine the impact of NH3(g) emissions from seabird guano on boundary-layer composition and nss-SO42− neutralization. A GEOS-Chem simulation without seabird emissions underestimated boundary layer NH3(g) by several orders of magnitude and yielded highly acidic aerosol. A simulation that included seabird NH3 emissions was in better agreement with observations for both NH3(g) concentrations and nss-SO42− neutralization. This is strong evidence that seabird colonies are significant sources of NH3 in the summertime Arctic, and are ubiquitous enough to impact atmospheric composition across the entire Baffin Bay region. Large wildfires in the Northwest Territories were likely an important source of NH3, but their influence was probably limited to the Central Canadian Arctic. Implications of seabird-derived N-deposition to terrestrial and aquatic ecosystems are also discussed.
Metastatic papillary thyroid carcinoma to the nose: report and review of cutaneous metastases of papillary thyroid cancer
Authors: Cohen Philip R. 
Published: February 2016

Background: Metastatic papillary thyroid carcinoma typically appears in local lymph nodes. Skin metastases are rare.
Purpose: A man with progressive metastatic papillary thyroid carcinoma who developed a cutaneous metastasis on his nose is described. The clinical manifestations of metastatic papillary thyroid carcinoma to skin are reviewed.
Methods: PubMed was used to search the following terms, separately and in combination: basal, cancer, carcinoma, cell, cutaneous, kinase, inhibitor, metastases, nose, papillary, rearranged during transfection, receptor, RET, thyroid, tyrosine, vandetanib.
Results: Pathologic changes observed on the biopsy of the man’s nose lesion were similar to those of his original cancer. Genomic evaluation of the tumor revealed an aberration involving the rearranged during transfection (RET) receptor tyrosine kinase. The residual tumor was excised. Treatment with vandetanib, a RET inhibitor was initiated; his metastatic disease has been stable, without symptoms or recurrent cutaneous metastasis, for 2 years following the discovery of his metastatic nose tumor.
Conclusions: Papillary thyroid carcinoma with skin metastases is rare. Nodules usually appear on the scalp or neck; the thyroidectomy scar is also a common site. Metastatic tumor, albeit infrequently, can present as a nose lesion. The prognosis for patients with cutaneous metastases from papillary thyroid carcinoma is poor. However, with the ability to test the tumor for genomic aberrations, molecular targeted therapies—such as tyrosine kinase inhibitors—may provide extended survival in these individuals.
Dermoscopic findings in different clinical variants of lichen planus. Is dermoscopy useful?
Authors: Friedman Paula , Cohen Sabban Emilia , Marcucci Carolina , Peralta Rosario , Cabo Horacio 
Published: February 2016

Lichen planus (LP) is a papulosquamous dermatosis that involves the skin, scalp, nails and mucous membranes. Although its pathogenesis is still unknown, there is evidence that an imbalance of immunologic cellular reactivity plays an important role. Histopathologic examination reveals characteristic interface dermatitis.
Dermoscopy is a non-invasive tool, useful in the assessment of inflammatory dermatoses, such as lichen planus. In this paper we describe the dermoscopic findings of different variants of LP (ungual, cutaneous, planopilaris, pigmentosus).
Next-Generation Sequencing Informatics: Challenges and Strategies for Implementation in a Clinical Environment
Authors: Roy Somak , LaFramboise William A. , Nikiforov Yuri E. , Nikiforova Marina N. , Routbort Mark J. , Pfeifer John , Nagarajan Rakesh , Carter Alexis B. , Pantanowitz Liron 
Published: February 2016

Context.—Next-generation sequencing (NGS) is revolutionizing the discipline of laboratory medicine, with a deep and direct impact on patient care. Although it empowers clinical laboratories with unprecedented genomic sequencing capability, NGS has brought along obvious and obtrusive informatics challenges. Bioinformatics and clinical informatics are separate disciplines with typically a small degree of overlap, but they have been brought together by the enthusiastic adoption of NGS in clinical laboratories. The result has been a collaborative environment for the development of novel informatics solutions. Sustaining NGS-based testing in a regulated clinical environment requires institutional support to build and maintain a practical, robust, scalable, secure, and cost-effective informatics infrastructure.
Objective.—To discuss the novel NGS informatics challenges facing pathology laboratories today and offer solutions and future developments to address these obstacles.
Data Sources.—The published literature pertaining to NGS informatics was reviewed. The coauthors, experts in the fields of molecular pathology, precision medicine, and pathology informatics, also contributed their experiences.
Conclusions.—The boundary between bioinformatics and clinical informatics has significantly blurred with the introduction of NGS into clinical molecular laboratories. Next-generation sequencing technology and the data derived from these tests, if managed well in the clinical laboratory, will redefine the practice of medicine. In order to sustain this progress, adoption of smart computing technology will be essential. Computational pathologists will be expected to play a major role in rendering diagnostic and theranostic services by leveraging “Big Data” and modern computing tools.
Analyzing Ambiguity of Context-Free Grammars
Authors: Brabrand Claus , Giegerich Robert , Møller Anders 
Published: February 2016

<p>It has been known since 1962 that the ambiguity problem for context-free grammars is undecidable. Ambiguity in context-free grammars is a recurring problem in language design and parser generation, as well as in applications where grammars are used as models of real-world physical structures. However, the fact that the problem is undecidable does not mean that there are no useful <em>approximations</em> to the problem.<br /> <br />We observe that there is a simple linguistic characterization of the grammar ambiguity problem, and we show how to exploit this to conservatively approximate the problem based on local regular approximations and grammar unfoldings. As an application, we consider grammars that occur in RNA analysis in bioinformatics, and we demonstrate that our static analysis of context-free grammars is sufficiently precise and efficient to be practically useful.</p><p> </p><p>Full text: <a href="http://dx.doi.org/10.1016/j.scico.2009.11.002" target="_self">http://dx.doi.org/10.1016/j.scico.2009.11.002</a></p>
Strong Concatenable Processes: An Approach to the Category of Petri Net Computations
Authors: Sassone Vladimiro 
Published: February 2016

We introduce the notion of <em>strong concatenable process</em> for Petri nets as the least refinement of non-sequential (concatenable) processes which can be expressed abstractly by means of a <em> functor</em> Q[_] from the category of Petri nets to an appropriate category of symmetric strict monoidal categories with free non-commutative monoids of objects, in the precise sense that, for each net N, the strong concatenable processes of N are isomorphic to the arrows of Q[N]. This yields an axiomatization of the causal behaviour of Petri nets in terms of symmetric strict monoidal categories.<br /> <br />In addition, we identify a <em>coreflection</em> right adjoint to Q[_] and we characterize its replete image in the category of symmetric monoidal categories, thus yielding an abstract description of the category of net computations.
An Equational Axiomatization for Multi-Exit Iteration
Authors: Aceto Luca , Fokkink Willem Jan 
Published: February 2016

<p>This paper presents an equational axiomatization of bisimulation equivalence over the language of Basic Process Algebra (BPA) with multi-exit iteration. Multi-exit iteration is a generalization of the standard binary Kleene star operation that allows for the specification of agents that, up to bisimulation equivalence, are solutions<br />of systems of recursion equations of the form</p><p>X1 = P1 X2 + Q1<br />...<br />Xn = Pn X1 + Qn</p><p>where n is a positive integer, and the Pi and the Qi are process terms. The addition<br />of multi-exit iteration to BPA yields a more expressive language than that obtained by augmenting BPA with the standard binary Kleene star (BPA). As a<br />consequence, the proof of completeness of the proposed equational axiomatization<br />for this language, although standard in its general structure, is much more involved<br />than that for BPA. An expressiveness hierarchy for the family of k-exit iteration operators proposed by Bergstra, Bethke and Ponse is also offered.</p><p> </p>
Hardness Results for Dynamic Problems by Extensions of Fredman and Saks’ Chronogram Method
Authors: Husfeldt Thore , Rauhe Theis 
Published: February 2016

We introduce new models for dynamic computation based on the cell probe model of Fredman and Yao. We give these models access to nondeterministic queries or the right answer +-1 as an oracle. We prove that for the dynamic partial sum problem, these new powers do not help, the problem retains its lower bound of Omega(log n/log log n). <br />From these results we easily derive a large number of lower bounds of order Omega(log n/log log n) for conventional dynamic models like the random access machine. We prove lower bounds for dynamic algorithms for reachability in directed graphs, planarity testing, planar point location, incremental parsing, fundamental data structure problems like maintaining the majority of the prefixes of a string of bits and range queries. We characterise the complexity of maintaining the value of any symmetric function on the prefixes of a bit string.
Low Redundancy in Dictionaries with O(1) Worst Case Lookup Time
Authors: Pagh Rasmus 
Published: February 2016

A static dictionary is a data structure for storing subsets of a finite universe U, so that membership queries can be answered efficiently. We study this problem in a unit cost RAM model with word size Omega(log |U|), and show that for n-element subsets,<br />constant worst case query time can be obtained using B +O(log log |U|)+o(n) bits of storage, where B = [log2 (|U| / n)]<br />is the minimum number of bits needed to represent all<br />such subsets. The solution for dense subsets uses B + O( |U| log log |U| / log |U| ) bits of storage, and supports constant time rank queries. In a dynamic setting, allowing insertions and deletions, our techniques give an O(B) bit space usage.