bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Approach to Improve Soft Ground in a Railway Station Applying Air-Boosted Vacuum Preloading
Authors: Shen Yupeng , Wang Huihuang , Tian Yahu , Feng Ruiling , Liu Jiankun , Wu Lan 
Published: May 2015

Abstract
Conventional vacuum preloading usually does not meet the requirements to improve soft ground in railway stations due to its long duration and unstable drainage performance. This is because of the drainage capacity reduction over a prolonged period. To overcome these disadvantages, a new approach, called air-boosted vacuum preloading, was proposed to deal with the soft ground. To introduce the air-boosted vacuum preloading, principles of this new technology were first introduced in this paper, and then the whole process of the construction was listed. In order to verify the effectiveness of the proposed new method, four different sections were set up through measuring the settlement, the pore water pressure, and the groundwater table in a test field. The results showed that a more rapid improvement in the soils parameters was reached, especially in the vane shear strength and the compression modulus. Although the boosted action reduced the vacuum pressure to a certain degree, pressure differences between soils and the prefabricated vertical drains became much larger with the process of boosting, which lead to accelerate drainage. Preloading settlement of the boosted sections was greater than that of the conventional sections within the booster tube depth and was less beyond that depth. Similarly, the overall post-construction settlement was identical for both methods. Air-boosted vacuum preloading was thus recommended to treat soft soils for tight schedule projects.
Endovascular biopsy: Technical feasibility of novel endothelial cell harvesting devices assessed in a rabbit aneurysm model
Authors: Cooke Daniel L , Bauer Diana , Sun Zhengda , Stillson Carol , Nelson Jeffrey , Barry David , Hetts Steven W , Higashida Randall T , Dowd Christopher F , Halbach Van V , Su Hua , Saeed Maythem M 
Published: May 2015

The lack of safe and reliable methods to sample vascular tissue in situ limits discovery of the underlying genetic and pathophysiological mechanisms of many vascular disorders, including aneurysms. We investigated the feasibility and comparable efficacy of in vivo vascular endothelial cell sampling using a spectrum of endovascular devices. Using the rabbit elastase carotid aneurysm model we evaluated the performance of existing aneurysmal coils, intracranial stents, and stent-like devices to collect vascular endothelial cells. Additionally, we modified a subset of devices to assess the effects of alterations to coil pitch, coil wire contour, and stent surface finishing. Device performance was evaluated by (1) the number of viable endothelial cells harvested, (2) the degree of vascular wall damage analyzed using digital subtraction angiography and histopathological analysis, and (3) the ease of device navigability and retrieval. Isolated cells underwent immunohistochemical analysis to confirm cell type and viability. Coil and stent specifications, technique, and endothelial cell counts were tabulated and statistical analysis performed. Using conventional detachable-type and modified aneurysm coils 11 of 14 (78.6%) harvested endothelial cells with a mean of 7.93 (±8.33) cells/coil, while 15 of 15 (100%) conventional stents, stent-like devices and modified stents harvested endothelial cells with a mean of 831.33 (±887.73) cells/device. Coil stiffness was significantly associated with endothelial cell count in univariate analysis (p = 0.044). For stents and stent-like devices univariate analysis demonstrated stent-to-aorta diameter ratios (p = 0.001), stent length (p = 0.049), and the use of a pulling retrieval technique (p = 0.019) significantly predictive of endothelial cell counts, though a multivariate model using these variables demonstrated only the stent-to-aorta diameter ratio (p = 0.029) predictive of endothelial cell counts. Modified devices did not significantly impact harvesting. The efficacy and safety of existing aneurysm coils, intracranial stents and stent-like devices in collecting viable endothelial cells was confirmed. The technique is reproducible and the quantity and quality of collected endothelial cells is adequate for targeted genetic analysis.
A critical reappraisal of bilateral adrenalectomy for ACTH-dependent Cushing's syndrome
Authors: Reincke Martin , Ritzel Katrin , Oßwald Andrea , Berr Christina , Stalla Günter , Hallfeldt Klaus , Reisch Nicole , Schopohl Jochen , Beuschlein Felix 
Published: May 2015

ObjectiveOur aim was to review short- and long-term outcomes of patients treated with bilateral adrenalectomy (BADx) in ACTH-dependent Cushing's syndrome.MethodsWe reviewed the literature and analysed our experience with 53 patients treated with BADx since 1990 in our institution.ResultsBADx is considered if ACTH-dependent Cushing's syndrome is refractory to other treatment modalities. In Cushing's disease (CD), BADx is mainly used as an ultima ratio after transsphenoidal surgery and medical therapies have failed. In these cases, the time span between the first diagnosis of CD and treatment with BADx is relatively long (median 44 months). In ectopic Cushing's syndrome, the time from diagnosis to BADx is shorter (median 2 months), and BADx is often performed as an emergency procedure because of life-threatening complications of severe hypercortisolism. In both situations, BADx is relatively safe (median surgical morbidity 15%; median surgical mortality 3%) and provides excellent control of hypercortisolism; Cushing's-associated signs and symptoms are rapidly corrected, and co-morbidities are stabilised. In CD, the quality of life following BADx is rapidly improving, and long-term mortality is low. Specific long-term complications include the development of adrenal crisis and Nelson's syndrome. In ectopic Cushing's syndrome, long-term mortality is high but is mostly dependent on the prognosis of the underlying malignant neuroendocrine tumour.ConclusionBADx is a relatively safe and highly effective treatment, and it provides adequate control of long-term co-morbidities associated with hypercortisolism.
Remarkably Divergent Regions Punctuate the Genome Assembly of theCaenorhabditis elegansHawaiian Strain CB4856
Authors: Thompson Owen A , Snoek L Basten , Nijveen Harm , Sterken Mark G , Volkers Rita J M , Brenchley Rachel , van’t Hof Arjen , Bevers Roel P J , Cossins Andrew R , Yanai Itai , Hajnal Alex , Schmid Tobias , Perkins Jaryn D , Spencer David , Kruglyak Leonid , Andersen Erik C , Moerman Donald G , Hillier LaDeana W , Kammenga Jan E , Waterston Robert H 
Published: May 2015

AbstractThe Hawaiian strain (CB4856) of Caenorhabditis elegans is one of the most divergent from the canonical laboratory strain N2 and has been widely used in developmental, population, and evolutionary studies. To enhance the utility of the strain, we have generated a draft sequence of the CB4856 genome, exploiting a variety of resources and strategies. When compared against the N2 reference, the CB4856 genome has 327,050 single nucleotide variants (SNVs) and 79,529 insertion–deletion events that result in a total of 3.3 Mb of N2 sequence missing from CB4856 and 1.4 Mb of sequence present in CB4856 but not present in N2. As previously reported, the density of SNVs varies along the chromosomes, with the arms of chromosomes showing greater average variation than the centers. In addition, we find 61 regions totaling 2.8 Mb, distributed across all six chromosomes, which have a greatly elevated SNV density, ranging from 2 to 16% SNVs. A survey of other wild isolates show that the two alternative haplotypes for each region are widely distributed, suggesting they have been maintained by balancing selection over long evolutionary times. These divergent regions contain an abundance of genes from large rapidly evolving families encoding F-box, MATH, BATH, seven-transmembrane G-coupled receptors, and nuclear hormone receptors, suggesting that they provide selective advantages in natural environments. The draft sequence makes available a comprehensive catalog of sequence differences between the CB4856 and N2 strains that will facilitate the molecular dissection of their phenotypic differences. Our work also emphasizes the importance of going beyond simple alignment of reads to a reference genome when assessing differences between genomes.
Fertilizer effects in a triticale monoculture on sandy soil
Authors: Kádár Imre , Ragályi Péter 
Published: May 2015

Az MTA ATK TAKI Őrbottyáni Kísérleti Telepén karbonátos homoktalajon beállított NPK műtrágyázási tartamkísérlet 36–43. évében, 2006 és 2013 között vizsgáltuk a műtrágyázás hatását a tritikále fejlődésére, termésére és elemfelvételére. A termőhely talaja a főbb tápelemekben (N, P, K) gyengén ellátott, a szántott réteg 1% körüli CaCO3-ot és 1% humuszt tartalmaz. Az altalaj erősen karbonátos, az agyagos rész 5–10%. A talajvíz 8–10 m mélyen található, a terület aszályérzékeny. Évente a P- (0, 60, 120 kg P2O5·ha−1) és K-műtrágyákat (0, 100, 200, 300, 400 kg K2O·ha−1) ősszel szántás előtt, valamint a N (0, 80, 160 kg N·ha−1) felét ősszel, a másik felét tavasszal szórtuk ki 25%-os pétisó, 18%-os szuperfoszfát és 50%-os kálisó formájában. A kísérletből levonható főbb tanulságok:Talajgazdagító PK-műtrágyázás eredményeképpen a kontrolltalaj igen gyenge PK-ellátottsága a kielégítő 150–200 mg·kg−1 NH4-acetát+EDTA-oldható tartományba emelkedett a kísérlet 41. évében (2011-ben). A szuperfoszfáttal végzett trágyázás eredményeképpen igazolhatóan nőtt a feltalaj oldható S- és Sr-tartalma, mely az alkalmazott hazai Kóla-alapú/nyersanyagú eredetre vezethető vissza. A hazai szuperfoszfátok 18–22% körüli elemi Ca-, 13% S-, 7–8% P-, 1–2% Srkészlettel rendelkeztek.Nemcsak a homoktalaj rendkívül heterogén, hanem a rajta fejlődő termés mennyisége is extrém szórásokat mutatott. Az évek és kezelések között egy nagyságrendet elérő különbségek adódtak. Az évek átlagait tekintve ötszörös eltéréseket tapasztaltunk. Az „évhatások” kifejezettek voltak. Termésdepresszió léphet fel egyaránt az aszály/vízhiány és a túlbő csapadék fennállása esetén.A P-kínálattal nőtt a növényi részek P-, Mn- és Sr-készlete, míg a beépült Znmennyiség visszaesett. Fellépett a P-Mn szinergizmus, illetve a P-Zn antagonizmus. A Mo-koncentráció a növekvő NPK-műtrágyázással a szalmában 1/3-ára, a szemtermésben a felére zuhant.A vizsgált nyolc év alapján még nem ítélhető meg, hogy a tritikále mennyire alkalmas a monokultúrás termesztésre, de összevetve a telepen 52 éves ún. „örökrozs” kísérletünkkel, ez lehetővé válhat a jövőben.
Density of Crude Oil Saturated With Carbon Dioxide
Authors: Marra R. K. , Poettmann F. H. , Thompson R. S. 
Published: May 2015

Abstract
A correlation for determining the density of carbon dioxide-crude oil mixtures with engineering accuracy was developed. The correlation is based on the ideal solution principle. Apparent liquid densities for carbon dioxide were correlated as a function of pseudo liquid system density and carbon dioxide concentration. In the final working correlation the pseudo liquid system density is expressed as a function of pseudo liquid hydrocarbon density and carbon dioxide concentration. The pseudo densities are then corrected to reservoir conditions. The correlation is presented in both graphical and equation form and is easily adaptable to computer or hand held calculator applications.
The mean error for the 154 data points used to develop the correlation is + 1.39 percent, the average absolute error is 4.46 percent, and the standard deviation is 5.25 percent. An error analysis of the experimental data indicated that when removing the 20 points having the greatest deviation the mean error is + 0.06 percent, the average absolute error is 2.8 percent, and the standard deviation is 2.44 percent.
A review of the existing literature on density calculations shows that the great majority of the correlations are based on the theorem of corresponding states. These methods yield accurate results. However, the equations were developed for pure substances and mixing rules must be applied for complex mixtures making the equations less accurate and more complicated. In addition, most of the equations were developed without the consideration of non-hydrocarbons such as CO2. Generally, when non-hydrocarbons are introduced the correlations become less accurate. The correlations were not checked against crude oils or crude oil mixtures containing non-hydrocarbons.
The correlation presented in this paper provides a simple method for calculating the density of carbon dioxide crude oil mixtures with engineering accuracy. The densities are used for calculating formation volume factor, swelling, and in other reservoir engineering calculations.
Use of Tracers To Investigate Drilling Fluid Invasion and Oil Flushing While Coring
Authors: Brown A. , Marriott F. T. 
Published: May 2015

ABSTRACT
A procedure is described by which oil flushing during coring of steamed and unsteamed heavy oil formations can be estimated. Chemical tracers in the drilling mud are used to indicate if filtrate invasion is occurring. Core saturation analyses are coupled with data from high velocity corefloods and temperature-dependent residual oil saturation measurements to estimate oil flushing during coring.
The Impacts on Waterflood Management of Inducing Fractures in Injection Wells in the Prudhoe Bay Oil Field
Authors: Williams D. B. , Sherrard D. W. , Lin C. Y. 
Published: May 2015

ABSTRACT
The induced fracturing of water injection wells in the Prudhoe Bay Oil Field has been of concern since original waterflood pilot tests were conducted in 1978. Early step-rate tests showed that, as a result of the injection of cold (80°F) seawater into the 200°F Ivishak reservoir, the formation fracture gradient was significantly reduced. Interest peaked with the need to develop a water-flood management strategy soon after waterflooding commenced in the second half of 1984.
In order to address the fracturing question, in-depth studies of field injection trends, innovative pressure transient analyses of step-rate data, interpretation of specially designed injection well tests, and several simulation studies were conducted. The results from these independent approaches provided definitive and confirming evidence on the extent of fracturing; this was a crucial prerequisite to the definition of a long-term injection strategy.
Subsequently, the impact of formation breakdown on areal and vertical sweep and on oil production rates was evaluated, and it has been concluded that potential negative effects of inducing fractures with clean water injection into the Ivishak formation are minimal, while benefits include accelerated oil production. As a result, an injection pressure limit above the thermally reduced formation fracture gradient has been defined and adopted.
Development of Reservoir Descriptions To Aid in Design of EOR Projects
Authors: Chopra A. K. , Stein M. H. , Ader J. C. 
Published: May 2015

ABSTRACT
A new technique was developed to obtain reservoir descriptions to aid in the design of enhanced oil recovery (EOR) projects. This technique incorporates the reservoir performance during primary and secondary processes as well as the geological and petrophysical data. The advantage of this technique over statistical techniques is that a more realistic reservoir description can be obtained. The reservoir description when used with an EOR reservoir simulator would yield a more realistic prediction of EOR performance and minimize the risk in an EOR field project. This technique may also be used to validate a reservoir simulator for field scale EOR performance. If the reservoir description is derived independent of EOR performance, the reservoir description is based only on the reservoir heterogeneities. The EOR process variables can then be quantified from the EOR performance without changing the reservoir description (Ader and Stein1).
The application of this technique is illustrated for a 250 acre area of interest in a San Andres formation reservoir. The initial reservoir description is formulated based on permeability to porosity ratio plots, injection and production profiles, core data, and pressure transient tests. The initial gas saturations and pressures are obtained based on dimensionless performance curves. The reservoir description is then refined by history matching primary and secondary performance for individual wells using a reservoir simulator. For the example discussed in this paper, an excellent match of performance was achieved using this technique.
Laboratory Study of Foaming Surfactant for CO2 Mobility Control
Authors: Di Julio S. S. , Emanuel A. S. 
Published: May 2015

ABSTRACT
The effectiveness of foam as a mobility control agent has been tested by an immiscible CO2 core-flood displacement of a California heavy oil (14°API). The study was conducted with a parallel coreflood system consisting of two segmented unconsolidated reservoir cores with a permeability ratio of 3.7. This represented a physical model of two noncommunicating reservoir sand layers of different permeabilities.
Two base case parallel corefloods were performed by simultaneously waterflooding both cores, then injecting water and CO2 alternately (WAG). Oil recoveries for the two base cases were: Oil Recovery (% OOIP)Low Permeability CoreHigh Permeability CoreWaterflood046.4CO2-WAG0.46.7
The CO2-WAG was followed by CO2-foam.
Foam was produced by adding 0.5 wt% surfactant to the brine solution and then simultaneously injecting the surfactant solution and CO2. The surfactant was Chevron Proprietary Surfactant CRSO 85/66, selected for the given reservoir fluids and rock.
Injection of foam into the parallel core system produced an incremental recovery of 19% OOIP from the high permeability core and 52% OOIP from the low permeability core. The total incremental oil recovery over waterflood for CO2 and foam injection was 40% OOIP.
Results of this parallel coreflood study have demonstrated three points: The ability of foam to reduce CO2 mobility, which resulted in the incremental oil recovery from the high permeability core; andThe ability of foam to divert CO2 to the low permeability core which showed little recovery from waterflood or CO2-WAG.The ability of foam to recover an incremental of 33.6% of OOIP of heavy oil over the water-flood and CO2-WAG.
Horizontal Well Pressure Analysis
Authors: Ozkan E. , Raghavan R. , Joshi S. D. 
Published: May 2015

ABSTRACT
This paper presents an analysis of the pressure transient behavior of a horizontal well or a drainhole. The performance of horizontal wells and fully penetrating vertical fractures is compared. Dimensionless wellbore pressures are computed for two classical boundary conditions; namely infinite-conductivity and uniform-flux. Results are presented as pseudoskin factors and as type curves. In addition to conventional pressure versus time type curves, derivative type curves using pressure-time predictions are presented. The derivative approach we discuss here is new to the petroleum literature and is applicable to a broader range of problems than that considered here.
Computations suggest that horizontal well productivity is governed by two parameters: 1) the dimensionless well length, LD (LD=L/(2h)kz/k, where L is the length of the well, h is the formation thickness, and kz and k are the vertical and horizontal permeabilities, respectively), and 2) the dimensionless well radius, rwD, (the ratio of well radius to well half-length if the formation is assumed to be isotropic). Results indicate, that horizontal well productivity (infinite-conductivity) is almost identical to that of a fully penetrating vertical fracture of infinite-conductivity if the dimensionless horizontal well length, LD, is greater than 4.0. This result shows that horizontal wells may perform better than vertically fractured wells, if non-ideal aspects associated with vertically fractured wells such as limited conductivity or height, are taken into account.
Results have been obtained for LD in the range 0.1 ≤ LD ≤ 100 and dimensionless well radius, rwD, in the range 10−4 ≤ rwD ≤ 10−2; these ranges should encompass expected values of horizontal well length, reservoir height, and ratio of vertical and horizontal permeability. Pressure responses and pseudoskin factors are calculated for four different well locations within the productive interval. The pseudoskin factors are insensitive to well location.
Using Finite System Buildup Analysis To Investigate Fractured, Vugular, Stimulated, and Horizontal Wells
Authors: Mead H. N. 
Published: May 2015

ABSTRACT
The Rectangular Hyperbolic Method (RHM) is a steady state, finite system concept which has proved to be amazingly accurate in determining final static reservoir pressure at time of shutin. The method also calculates slope, skin, percentage of open reservoir thickness contributing to flow, effective drainage radius and permeability. It apparently also gives reasonable answers in horizontal well buildups. It has been found that all wellbore reservoir pressure buildups after all wellbore and storage effects have died out follow a rectangular hyperbolic curve. The analysis is based solely upon Darcy's steady state radial flow equation, the basic transient pressure buildup equation and the determination of effective drainage radius from Mt/Uo in an empirical equation based upon field date obtained from the literature. RHM is not related to any method based upon an infinite system concept.
A Simulator for Drillstem Test Interpretation
Authors: Hegeman P. S. , Abbaszadeh M. 
Published: May 2015

ABSTRACT
An analytical drillstem test (DST) simulator has been developed. The simulator can be used to verify the interpretation of drillstem tests with insufficient or poor quality flow rate data. Therefore, the immediate application of the simulator will be to improve the interpretation of drillstem tests that do not flow to the surface. A common example of such a test is a DST conducted on-land, open-hole, where rate measurement devices are rarely used because they are expensive relative to the cost of the test.
The simulator was designed to be consistent with the quality of pressure and rate (or fluid recovery) data measured on most non-surface flowing DST's. Although rate data may be inaccurate during flow periods, the measured pressures are usually reliable. Therefore, the DST is modeled as a sequence of alternating pressure-specified flow periods and rate-specified buildup periods. The interpretation is verified by comparing both simulated vs. measured pressures and fluid recoveries.
Using field data, it is shown that this simulator can be used to enhance the interpretation of non-surface flowing DST's.
New Methods for Estimating Parameters of Low Permeability Reservoirs
Authors: Kuchuk F. J. 
Published: May 2015

Abstract
The use of simultaneously measured downhole pressure and flow rate may not completely eliminate wellbore storage or afterflow effects when there is considerable additional wellbore volume below the pressure gauge and flowmeter. This paper presents new interpretation methods with or without measured wellbore flow rate, taking the additional wellbore volume into account. A diagnostic method is also presented for the determination of the correct logarithmic convolution straight line.
It is shown that a simple deconvolution (β-deconvolution) is possible when the wellbore flow rate increases (drawdown) or decreases (buildup) exponentially.
For partially penetrated wells, it is also shown that the vertical permeability can be obtained from either the onset of the semilog straight line if it evolves or the simultaneous use of the deconvolution and the convolution associated with non-linear estimation.
New solutions are presented for infinite-conductivity vertically fractured wells with wellbore storage (including the fracture storage, which may be important even if the flow rate is measured at the wellbore) and skin effects.
Two examples are presented to demonstrate the use of the new interpretation methods for both drawdown and buildup tests.