bluuebunny/crossref_metadata_2025_split huggingface dataset:
Allozyme variation in natural populations of Picea asperata
Authors: Luo Jianxun , Wang Yuhua , Korpelainen Helena , Li Chunyang 
Published: September 2014

A survey of allozymic alleles and genetic diversity was conducted for ten natural populations of Picea asperata Mast. originating from the mountains of Southwest China. AÂ total of twenty-seven alleles at seventeen loci were observed. Ten of the loci were found monomorphic. Our results showed that the populations sampled were characterized by low genetic diversity (mean He = 0.096) and a low level of inbreeding (mean Fis = 0.005). The UPGMA tree of genetic relationships indicated that there was significant differentiation among populations. The coefficient of genetic differentiation among populations, based on Fst, equaled 0.311. Such extensive inter-populational differentiation detected in P. asperata could have resulted from allele frequency divergence among populations, particularly, in one population. Introgression from another species, variation in environmental conditions, and differing selection pressures could be some of the factors attributing to significant differences among populations. In addition, our results showed that the geographic and genetic distances were not correlated in the populations of P. asperata. Based on the genetic information obtained, we concluded that monitoring appropriate genetic markers may be an effective means of identifying potential genetic changes occurring during forest tree evolution.
Boundary Layers in a Two-Point Boundary Value Problem with a Caputo Fractional Derivative
Authors: Stynes Martin , Gracia José Luis 
Published: September 2014

Abstract
A two-point boundary value problem is considered on the interval

[
0
,
1
]

$[0,1]$

, where the leading term in the differential operator is a Caputo fractional derivative of order δ with

1
<
δ
<
2

$1&lt;\delta &lt;2$

. Writing u for the solution of the problem, it is known that typically

u

'
'

(
x
)

$u^{\prime \prime }(x)$

blows up as

x
→
0

$x\rightarrow 0$

. A numerical example demonstrates the possibility of a further phenomenon that imposes difficulties on numerical methods: u may exhibit a boundary layer at x = 1 when δ is near 1. The conditions on the data of the problem under which this layer appears are investigated by first solving the constant-coefficient case using Laplace transforms, determining precisely when a layer is present in this special case, then using this information to enlighten our examination of the general variable-coefficient case (in particular, in the construction of a barrier function for u). This analysis proves that usually no boundary layer can occur in the solution u at x = 0, and that the quantity

M
=

max

x
∈
[
0
,
1
]

b

(
x
)

$M = \max _{x\in [0,1]}b(x)$

, where b is the coefficient of the first-order term in the differential operator, is critical: when

M
<
1

$M&lt;1$

, no boundary layer is present when δ is near 1, but when M ≥ 1 then a boundary layer at x = 1 is possible. Numerical results illustrate the sharpness of most of our results.
Sifting the sand on the river bank: Social media as a source for research data
Authors: Metaxas Panagiotis , Mustafaraj Eni 
Published: September 2014

Abstract
Computational social science has been described as a new field at the
intersection of computer science and social sciences, aiming to study
the ways that society evolves, interacts, and reacts. Like prospectors
sifting the sand in a river bed for gold, computational social science
researchers are looking into the streams of social media for insight
on our social interactions. Enabled by the availability of and easy
accessibility to vast amounts of data generated by social entities, as
well as by powerful computing hardware and algorithms, its researchers
conduct observations of social interaction and experiments testing
social theories in scales not realizable before. In this paper, after
a short review of the characteristics of this new area, we discuss
issues related to the types of data sought and used, and some of the
challenges in collecting and interpreting the data. Throughout the
paper we also examine some of the pitfalls awaiting and the standards
that need to be observed.
Integration of human papillomavirus type 16 in cervical cancer cells
Authors: Gudleviciene Zivile , Kanopiene Daiva , Stumbryte Ausra , Bausyte Raminta , Kirvelaitis Edgaras , Simanaviciene Vaida , Zvirbliene Aurelija 
Published: September 2014

Abstract
Cervical cancer remains an important cause of
women morbidity and mortality. The progression of cervical
pathology correlates with the HPV integration into the host
genome. However, the data on the viral integration status in
cervical dysplasias are controversial. The aim of the current
study was to evaluate the status of HPV integration in two
types of cervical pathology – invasive and non invasive
cervical cancer (e.g. carcinoma in situ). 156 women were
included in the study: 66 women were diagnosed with
invasive cervical cancer (CC) and 90 with non invasive cervical
cancer (carcinoma in situ, CIS). 74.2% [95% PI: 63.64÷84.76]
of specimens collected from women with diagnosed CC
and 85.6% [95% PI: 85.53÷92.85] of CIS specimens were
positive for HPV. The most prevalent HPV genotype in both
groups was HPV16. To evaluate HPV integration, three
selected HPV16 E2 gene fragments were analyzed by PCR.
In the majority of CC and CIS specimens the amplification
of all three HPV16 E2 gene fragments was observed. The
episomal HPV16 form was detected in the majority of CC
and CIS specimens. The deletion of all three HPV16 E2 gene
fragments was detected in 9.4% of CC specimens and 2.2%
of CIS specimens. Finally, integration status could not be
used as diagnostical additional test to distinguish between
invasive and non invasive cervical cancer.
Lithium transition metal pnictides – structural chemistry, electrochemistry, and function
Authors: Winter Florian , Pöttgen Rainer , Greiwe Magnus , Nilges Tom 
Published: September 2014

Abstract
Lithium-transition metal (T)-pnictides (Pn=P, As, Sb, Bi) are an interesting class of materials with greatly differing crystal structures. The transition metal and pnictide atoms build up covalently bonded networks that leave cavities or channels for the lithium atoms. Depending on the bonding of lithium to the polyanionic network, one observes mobility of the lithium atoms. The crystal chemistry, chemical bonding, 7Li solid-state NMR, and the electrochemical behavior of the pnictides are reviewed. The structural chemistry is compared with related tetrelides.
An Evaluation of Three Triaxial Systems With Results From 0.1 to 100 MPa
Authors: Casey Brendan , Germaine John T. 
Published: September 2014

Abstract
This paper evaluates the results of triaxial tests carried out over a very wide range of effective stresses using custom-built triaxial systems specially developed for testing at low, medium, and high pressures. These tests were performed on samples of resedimented Boston Blue Clay, and good reproducibility is demonstrated across testing devices. A novel approach was taken to evaluate the effect of apparatus compressibility of the drainage system on the measured undrained shear behavior, as this issue becomes increasingly important for triaxial testing at high stresses. The effect of apparatus compressibility on triaxial shear results was evaluated by comparing the volume of pore fluid necessary to develop the drained strength of a specimen to the volume of flow caused by apparatus compressibility. This method is more illustrative and intuitive for undrained triaxial testing of saturated specimens than the traditional approach of using a specimen's B-value. Triaxial test results show a consistent decrease in both undrained strength ratio and critical state friction angle over the effective stress range of 0.1 to 100 MPa for each overconsolidation ratio investigated. The conventional assumption made in soil models that fine-grained soils exhibit constant normalized strength properties is therefore shown to be invalid when these properties are viewed over a significant range of effective stresses.
Partial Decarburization and Intensive Quenching to Increase Fatigue Limit of Quenched Small Parts
Authors: Lozano D. E. , Totten G. E. , Martinez-Cazares G. M. , Mercado-Solis R. 
Published: September 2014

AbstractThe 5160 spring steel is mainly used to endure fatigue and since its Mf is below room temperature, retained austenite is usually present after conventional quenching, which is detrimental from a fatigue point of view. To reduce the amount of retained austenite, a partial decarburization was promoted (to increase the Ms and Mf, respectively) by austenitizing the steel at different temperatures and times in air, prior to performing an interrupted quenching in an accelerated media (brine) instead of the conventional oil quenching. The same quenching conditions with partial decarburization and without decarburization are compared. In addition, conventional oil quenching was performed as reference. Results showed that with a controlled partial decarburization, it is possible to increase the fatigue limit compared to the conditions without decarburization (both interrupted quenching and oil quenching). Fatigue experiments were carried out in a rotating bending fatigue type tester. Cooling curves, decarburization profiles, fraction of martensite plots, and fatigue data are discussed.
Improvement of carbon nanocoil purity achieved by supplying catalyst molecules from the vapor phase in chemical vapor deposition
Authors: Suda Yoshiyuki , Ishii Yuichi , Miki Tatsuki , Maruyama Koji , Tanoue Hideto , Takikawa Hirofumi , Ue Hitoshi , Shimizu Kazuki , Umeda Yoshito 
Published: September 2014

Abstract
State of Art in Prediction of Fluvial Sandbodies in Low Permeable Tyumen Formation of West Syberia
Authors: Martynov M. E. , Shishmanidi I. V. , Kozlov A. V. , Leskin F. Y. 
Published: September 2014

Abstract
Effective development of hard-to-recover reserves is one of the key activities of Russian oil companies. Great interest in this category of deposits is related to significant reserves. Prospective target for the development in Krasnoleninskoye field are deeply buried continental deposits of Tyumen formation which are related to the category of hard-to-recover reserves. Tyumen Formation is represented by interbedded sandstone, siltstone, shale, coal and characterized by low reservoir properties, average porosity and permeability are 12 % and 0.4 md, respectively. Despite numerous attempts to come to full-scale development of these deposits - and this has become possible only since the late 90's after the introduction of hydraulic fracturing technology, but there was no significant results. The main problem in this case is very complex geological structure, and if the problem of low permeability is solved by reservoir stimulation using hydraulic fracturing, the problem of spatial distribution prediction of the sandbodies is still actual, which in turn is a cause of low drilling success, flowrates and difficulties in effective waterflooding design. At the present an attempt solving the problem by drilling horizontal wells to enter maximum amount of sandbodies and their involvement in the development at the expense of a multistage hydraulic fracturing. This paper considers an example of the successful application of the engineering approach by integrating data from various lines of inquiry (seismic, geology and reservoir engineering, well testing) in order to forecast continental deposits of Tyumen formation and successful exploration drilling organization.
The Results of the Field Tests and Prospects of Termogas Development of Bazhenov Formation in OJSC RITEK
Authors: Kokorev V. I. , Darishchev V. I. , Akhmadeishin I. A. , Shchekoldin K. A. , Boksernam A. A. 
Published: September 2014

Abstract
The paper covers the distinctive features of thermogas stimulation for Bazhenov formation, gives data resulted from the experimental work performed at Sredne-Nazym field of OJSC "RITEK"
At present structural deterioration of reserves is in progress due to the increased share of heavy-to-recover and unconventional hydrocarbons in the total structure of the Russian raw-material base.
Most of unconventional hydrocarbon resources of Russia are found in Bazhenov oil source rocks (further on referred to as BS).
The urgency of BS effective development is necessitated by the fact that now the land of Russia stores nonessential quantity of actual reserves. While, nonconventional reserves are estimated at over 1 trillion tons, and a potential increase of recoverable reserves greatly exceeds local current recoverable reserves. Virtually, all non-conventional reserves are spread through the regions with developed infrastructure making it possible to cut the period for field tests and commercial application of new engineering decisions to involve into effective development the BS deposits being a form of the giant world shale hydrocarbon resources. According to foreign and local experts the potential of BS recoverable oil reserves amounts to minimum 30-40 bln. tons, and that is multiply higher than a possible increase of oil reserves owing to exploration of new Eastern Siberia and Arctic fields. To develop BS deposits the technical and technological complex to increase oil recovery based on integration of thermal and gas methods is under designing.
Non-Darcy Flow Numerical Simulation and Pressure/Rate Transient Analysis for Ultra-Low Permeable Reservoirs
Authors: Baikov V. A. , Davletbaev A. Ya. , Ivaschenko D. S. 
Published: September 2014

Abstract
The current progress in oilfield development is focused on ultra-low permeable reservoirs to be put in production. Experimental results show that fluid flow in ultra-low permeable reservoirs no longer obeys Darcy's law.
We investigate the pressure pattern behavior under a nonlinear relation between flow velocity and pressure gradient. The use of non-Darcy flow simulation in pressure/rate transient field data analysis exhibits new possibilities for estimating permeability and a drainage area. The results obtained show that the effective drainage area is significantly smaller than interwell distance in a development system cell. This may cause decision making for infill drilling in low-gradient areas.
Feasibility Evaluation of Perspective Geological Structures in Oil and Gas Production Regions with Highly Developed Infrastructure
Authors: Bulgakov S. A. , Ismagilov A. F. , Khamitov I. G. , Troshkov Yu. M. , Fedorchenko G. D. , Manasian A. E. 
Published: September 2014

Abstract
The paper considers the automated system to optimize the package of geological and exploration works. The distinctive feature of the proposed system contains the integrated approach from static record-keeping of reservoir distribution features and their formation properties to automated calculation of the field development and construction options for the promising objects. This method is aimed at economic potential evaluation in commissioning the small-sized hydrocarbon pools in oil and gas production provinces that have highly-developed infrastructure with due account for regional features. Validation of the proposed method was completed for the case with Kelveyskoye Licensed Area of OAO "Samaraneft-egas".
Algorithms of Automatic Core-Log Depth-Shifting In Problems of Petrophysical Model Construction
Authors: Nadezhdin O. , Zairullina E. , Efimov D. , Savichev V. 
Published: September 2014

Abstract
The problem of core-log depth matching/shifting is an integral part of any petrophysical interpretation and modeling. The correct and robust solution to this task predetermines the quality of the resultant petrophysical model however this solution is not straightforward. In this paper the authors present specific algorithms aimed at automated processing, depth shifting and calibration of downhole wireline logs and petrophysical properties measured in core analysis.
Application of 2D Technology of Digital Modeling for Prediction of Traps in the Sedimentary Cover
Authors: Ershov Andrey V. , Linev Dmitriy N. , Lineva Maria D. 
Published: September 2014

Abstract
Sedimentological modeling is one of the important parts of basin modeling. Processes of sedimentation and sedimentation environment mostly determine the final structure and properties of the geological play. So, to solve the direct problem means to find out the lithological and facies cross-section, being based on initial sedimentation environments and processes. The solution of the direct problem allows us to predict lithology and facies distribution of play of interest. Spatial resolution of the sedimentological model can be rather high, up to centimeters. Solution of the inverse problem helps us to reconstruct initial environments and conditions of sedimentation. If we have solved the inverse problem for well-explored areas, we could extrapolate the results to adjacent unexplored areas and predict sedimentary structure by solving the direct problem.
The designed Mazay2D forward sedimentary modelling software complex can perfom sedimentological modeling of erosion, distribution and accumulation of clastic deposits and formations, sedimentation and erosion of carbonate deposits (including reefs).
Sedimentary modeling technology solves direct problem (we know environment – we can calculate final structure of the geological play) and inverse problem (we have final structure – we can calculate processes of its sedimentation). The direct problem solution allows us to calculate lithology, gradation, porosity, permeability, density and other petrophysical characteristics. Elastic parameters and synthetic seismic profile can also be calculated.
Output data of sedimentological modelling can be used as input data in basin modeling to calculate, for example, porosity evolution during post-sedimentary stage.
Sedimentary modeling can be used to predict high-resolution lithological and facies structure of the reservoir, to plan geophysical research and as assistance for seismic interpretation. Besides, sedimentological model can be applied to basin modeling of hydrocarbon systems.
Practice and Future Potential of Multilateral Horizontal Drilling for Lower Permian Reservoirs: Case Study from Lemezinskoe Field
Authors: Krasnevsky Yu. S. , Ganeev A. I. , Mescheryakov O. E. , Chervyakova A. N. , Trofimov V. E. 
Published: September 2014

Abstract
Lemezinskoe oil field is situated in Iglinsky region, Republic of Bashkortostan, 84 km to the east of Ufa and 35 km to the south-east of the regional center Iglino. The field is located in the region with well-developed infrastructure. In the regional tectonic setting the field lies in the northern part of the Belsk Depression, Pre-Ural Foredeep Basin. It is associated with a buried Lower Permian reef build-up (P1ar-P1s). Oil shows of various intensity and nature were recorded in the Kungurian, Artinskian and Sakmarian sequences. Commercial oil reserves of Lemezinskoe field are discovered in the porous and permeable limestones of the productive Artiskian-Sakmarian reservoirs. The reef build-up consists of carbonates which differ in their mineral composition, origin, structure and texture as well as porosity and permeability. The oil is heavy, viscous, waxy and sour.
One production target is identified within the field and two reservoirs which are located at a considerable distance from each other. The key parameters of the developed Artiskian-Sakmarian Reservoir 1 (Reservoir 2 is not developed due to its location in the sanitary-protection zone) are summarized below.
The reservoir layers within the body of the reef are characterized by discreet spatial distribution. In most cases the permeable streaks are isolated by tight carbonate rocks. Well-to-well correlation of the reservoir intervals is impossible due to the heterogeneous lithology of the section. Geological cross-sections show the distribution of the reservoir intervals only in the wells whereas in the interwell space the presumed distribution pattern is rather schematic and simplified (Fig. 1). One distinct feature of Lemezinskoe field as a reefal build-up is lack of biodegrated oil or gas cap.
Review of a Forgotten Technology With High Potential - The World Largest Nitrogen Based IOR Project in the Supergiant Field Cantarell, Mexico
Authors: Guzmann Marcus S. 
Published: September 2014

Abstract
This paper provides a compelling review about the world largest nitrogen IOR project in the supergiant field Cantarell, an oil field offshore Gulf of Mexico. Cantarell is Mexico's largest resource being operated by Pemex. The very successful IOR project includes the daily injection of up to 1.5 bn scf (50.000 tons) per day of nitrogen for pressure maintenance since year 2000.
The basic reservoir characteristic and production history will be discussed, including the very positive field response of more than doubling the oil production from 1.0 million to 2.2 million bblpd. Alternative EOR technologies are techno-commercially assessed. The supply of the required nitrogen volumes by air separation plants and the associated infrastructure will be explained in detail.
The conclusion is that nitrogen for pressure maintenance (IOR) including the use of nitrogen for gas lift is a state-of-the-art technology with proven success in offshore fields.
Injection Test of Carbonate Reservoir with Complex Porosity Types Including Porous Matrix, Fractures, Vuggy Zones
Authors: Abdullin R. , Davletbaev A. , Bikbulatova G. , Ignatev A. , Yamalov I. 
Published: September 2014

Summary
Water flooding of carbonate reservoirs with complex porosity, fracture system and high vugginess is complicated by water breakthrough and quick waterflooding of the producers. At that, reservoir pressure maintenance is essential means as due to reduced reservoir energy state resulting from formation and bottom hole pressure decrease at elasto-plastic drive, well production rate decreases. Analyses of well test study show that pressure drop fracture healing takes place and leads to production loss of the producers. High vertical permeability leads to technogenic formation of gas caps at reservoir pressure drawdown below bubble point pressure and to necessity of shutting off some producers drilled under the field arch.
To reduce water flooding in producers and involve non-draining uninvaded areas to injection high-elastic solutions are injected. This helps to distribute the fluid injected to uninvaded intervals. As a rule, fracture system and secondary porosity are less developed in these intervals. For that reason the reservoir are of less permeability.
Liduid injection to the wells is carried out at high pressures. According to transient well test results which were undertaken before and after injection of high-elastic solutions large – spontaneous growth of vertical fracture in injection wells are observed. Thus, according to log-log plot after the undertakings logarithmic derivative view (flow pattern for single vertical fractures) is fundamentally changed. Field research results show that after the injection of high-elastic solutions and further injection at high pressure rates in reservoirs with bad flow properties artificial hydrofracs are forming which helps to involve earlier non-draining intervals.