bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gravity Wave Refraction by Three-Dimensionally Varying Winds and the Global Transport of Angular Momentum
Authors: Hasha Alexander , Bühler Oliver , Scinocca John 
Published: September 2008

Abstract
Operational gravity wave parameterization schemes in GCMs are columnar; that is, they are based on a ray-tracing model for gravity wave propagation that neglects horizontal propagation as well as refraction by horizontally inhomogeneous basic flows. Despite the enormous conceptual and numerical simplifications that these approximations provide, it has never been clearly established whether horizontal propagation and refraction are indeed negligible for atmospheric climate dynamics. In this study, a three-dimensional ray-tracing scheme for internal gravity waves that allows wave refraction and horizontal propagation in spherical geometry is formulated. Various issues to do with three-dimensional wave dynamics and wave–mean interactions are discussed, and then the scheme is applied to offline computations using GCM data and launch spectra provided by an operational columnar gravity wave parameterization scheme for topographic waves. This allows for side-by-side testing and evaluation of momentum fluxes in the new scheme against those of the parameterization scheme. In particular, the wave-induced vertical flux of angular momentum is computed and compared with the predictions of the columnar parameterization scheme. Consistent with a scaling argument, significant changes in the angular momentum flux due to three-dimensional refraction and horizontal propagation are confined to waves near the inertial frequency.
Novel Fabrication of ZnO Film-coated Carbon Nanotube Arrays in Modified AAO Membrane
Authors: Yu Kailu , Wang Wenhua , Luo Taigang 
Published: September 2008

Abstract
The AAO membrane was modified by immersion within Zn(NO3)2 solution. Zinc-containing film would be formed over the inner surfaces of membrane. Using this as template, ZnO film-coated carbon nanotube arrays were fabricated in plasma-enhanced CVD.
Quality of life measures in pediatric cardiology
Authors: Berkes Andrea , Mogyorósy Gábor 
Published: September 2008

Az utóbbi néhány évtizedben ugrásszerű fejlődést mutató gyermek-szívsebészeti, illetve -kardiológiai ellátás területén napjainkban joggal merül fel az igény a kezelés eredményességének betegszempontú elemzésére. Az életminőség-mérésekkel kapcsolatos szakmai elvárások, illetve azok felhasználási lehetőségei gyakran ismeretlenek a gyakorló orvosok számára. A gyermekkori mérések számos nehézsége, a korrekt vizsgálatok alacsonyabb száma miatt ez különösen igaz a gyermekgyógyászat területére.
Cél:
A gyermekkardiológia területén zajló életminőség-mérésekkel szemben támasztott alapvető szakmai elvárások és az eddigi vizsgálatok eredményeinek klinikai szempontú ismertetése.
Módszer:
Irodalmi áttekintés felnőtt-, illetve gyermekkorú, szívfejlődési rendellenességgel született vegyes populációs és speciális betegcsoportok körében végzett életminőség-mérésekről, a vizsgálatok fő eredményeinek és alapvető módszertani jellemzőinek bemutatásával.
Következtetés:
Az eddigi vizsgálatok eredményei szerint az életminőség-méréseknek helye van a gyermekkardiológiai ellátásban. Megfelelően kivitelezett mérésekkel a gondozás színvonala javítható.
Diclofenac/orphenadrin as a combined analgetic in post-operative relief of pain
Authors: Borsodi Marianna , Nagy Edina , Darvas Katalin 
Published: September 2008

A szerzők a kombinált, nemszteroid gyulladásgátló diclofenac- és centrális izomrelaxáns orphenadrintartalmú infúzió és a tramadolium chloratum hatásosságát, biztonságosságát és tolerálhatóságát hasonlították össze kis és közepes műtéteket követően, a posztoperatív fájdalomcsillapítás során. A vizsgálat nyílt, csoport- és önkontrollos, prospektív, randomizált, IV. fázisú klinikai vizsgálat volt. A bevont 60 beteg összesen 74 napon át kapott fájdalomcsillapítót. A betegeket három csoportba sorolták: a diclo­fenac-orphenadrint kapó
A
(
n
= 19), a tramadolt kapó
B
(
n
= 30) és a diclofenac-orphenadrint és tramadolt is kapó
C
(
n
= 11) csoportba. A kapott adatokat statisztikailag elemezték. A fájdalomcsillapítók hatásának megítéléséhez a vizuális analóg skálát (VAS) használták. A VAS-értékek a kezelés hatására mindhárom csoportban mind nyugalomban (–2,5, –3,7, –3,0), mind mozgásban (–3,0, –3,8, –3,4) szignifikánsan (
p
< 0,001) csökkentek, tehát mindhárom csoportban hatásos volt a fájdalomcsillapítás. Ezt a keringési paraméterek elemzése is alátámasztotta. A kezelés végén mind a betegek, mind az orvosok szignifikánsan (
p
< 0,05, illetve
p
< 0,01) kedvezőbbnek ítélték a hatásosságot a csak diclofenac-orphenadrin infúziót kapó
A
csoportban. Az alkalmazott fájdalomcsillapítók mennyiségét elemezve a
C
csoportban kiegészítésként adott tramadol mennyisége szignifikánsan alacsonyabb volt a csak tramadolt kapó
B
csoporthoz képest (
B:
87,5 mg,
C:
61,5 mg,
p
< 0,01), azaz a diclofenac-orphenadrin infúzió a tramadol fájdalomcsillapító hatását erősítette. A kezelés elején és végén mért laboratóriumi paraméterek a fiziológiás értékhatárokon belül voltak, mellékhatásként összesen 3 esetben észleltek hányingert, illetve hányást. Mindezek alapján a diclofenac-orphenadrin infúziót a kis és középkategóriájú műtétek utáni fájdalomcsillapításban hatásos, biztonságos, kényelmesen adagolható és jól kombinálható fájdalomcsillapítónak tartják.
Movement of Reservoir‐Stocked Riverine Fish between Tailwaters and Rivers
Authors: Spoelstra Jeffrey A. , Stein Roy A. , Royle J. Andrew , Marschall Elizabeth A. 
Published: September 2008

AbstractThe movement of fish from onstream impoundments into connected streams and rivers has traditionally been overlooked in fish stocking decisions but is critical to the ultimate impact of stocking riverine species into reservoirs. Hybrid saugeyes (female walleye Sander vitreus × male sauger S. canadensis) stocked into Deer Creek Reservoir, Ohio, readily move from the reservoir to the tailwater below. Downstream movement of these saugeyes from the tailwater may have consequences for native prey species and parental stocks downstream. We used fixed‐station radiotelemetry to quantify the temporal movement patterns of 203 reservoir‐stocked saugeyes from the tailwater of the reservoir, the stream flowing from the tailwater, and the river into which the stream flowed. From October 1998 through July 2000, most (75%) saugeyes never left the tailwater, and those that left returned 75% of the time. Overall, saugeyes spent 90% of their time in the tailwater, 7‐8% of their time downstream in small streams, and 2‐3% of their time farther downstream in the Scioto River (45 km downstream). No radio‐tagged saugeyes moved to the Ohio River (155 km downstream). The probability of downstream movement generally increased with increasing flow and when dissolved oxygen dropped to lethal levels in summer. The probability of movement was highest in winter and spring, when it was probably related to spawning, and low in summer (except when dissolved oxygen was low) and fall. The patterns of movement seemed to reflect the relative suitability of tailwater over stream habitat. The predominant use of and return to tailwater habitat after downstream movement limited overall stream and river residence time. Although the daily movement probability for an individual was low, when we apply these rates to all of the stocked saugeyes in the Ohio River drainage, we cannot safely conclude that only small numbers move from reservoir tailwaters to downstream river systems. We recommend that managers refrain from stocking systems for which there are concerns about native species in connected drainages.
Breeding Success of Wild and First‐Generation Hatchery Female Spring Chinook Salmon Spawning in an Artificial Stream
Authors: Schroder Steven L. , Knudsen Curtis M. , Pearsons Todd N. , Kassler Todd W. , Young Sewall F. , Busack Craig A. , Fast David E. 
Published: September 2008

AbstractFirst‐generation hatchery and wild spring Chinook salmon Oncorhynchus tshawytscha from the upper Yakima River, Washington, were placed into an artificial stream and allowed to spawn. Seven independent test groups were placed into the stream from 2001 through 2005. No differences were detected in the egg deposition rates of wild and hatchery females. Pedigree assignments based on microsatellite DNA, however, showed that the eggs deposited by wild females survived to the fry stage at a 5.6% higher rate than those spawned by hatchery females. Subtle differences between hatchery and wild females in redd abandonment, egg burial, and redd location choice may have been responsible for the difference observed. Body size did not affect the ability of females to spawn or the survival of their deposited eggs. How long a female lived was positively related to her breeding success, but female origin did not affect longevity. The density of females spawning in portions of the stream affected both egg deposition and egg‐to‐fry survival. No difference, however, was found in the overall distribution patterns of the two types of females. Other studies that have examined the effects of a single generation of hatchery culture on upper Yakima River Chinook salmon have disclosed similar low‐level effects on adult and juvenile traits. The cumulative effect of such differences will need to be considered when hatcheries are used to restore depressed populations of Chinook salmon.
Field Estimation of a Lethal Oxythermal Niche Boundary for Adult Ciscoes in Minnesota Lakes
Authors: Jacobson Peter C. , Jones Thomas S. , Rivers Pat , Pereira Donald L. 
Published: September 2008

AbstractCiscoes Coregonus artedi are coldwater stenotherms that are sensitive indicators of ecological stressors, such as eutrophication and climate warming, that reduce coldwater habitat. Temperature and oxygen profile data were collected during cisco mortality events at 17 lakes during an unusually warm summer in Minnesota in 2006. Combinations of temperature and oxygen from the profiles were mapped onto a two‐dimensional niche space to directly quantify an oxythermal lethal niche boundary for ciscoes. Quantile regression was used to estimate the niche boundary that described lethal combinations of oxygen and temperature for cisco. The fitted lethal oxythermal niche boundary exhibited a curvilinear interaction between lethal temperatures and lethal oxygen concentrations. The lethal temperature under normoxia (about 8 mg/L) was estimated to be 24°C. Lethal temperatures were progressively less at lower lethal oxygen concentrations (e.g., the lethal temperature was 23.0°C at 5.0 mg/L, 22.0°C at 3.0 mg/L, and 19.5°C at 1.0 mg/L). The lethal oxythermal niche boundary provides a basis for quantifying coldwater cisco habitat under current and future climate warming and water quality conditions.
Distribution and Use of Shallow‐Water Habitats by Pacific Sand Lances in Southeastern Alaska
Authors: Johnson Scott W. , Thedinga John F. , Munk Kristen M. 
Published: September 2008

AbstractThe Pacific sand lance Ammodytes hexapterus is an important prey species, but little is known about its distribution and habitat use, especially among early life stages in southeastern Alaska. To address this information need, we examined the distribution and habitat use of Pacific sand lances by sampling a variety of shallow‐water habitats (depth < 6 m) with a beach seine seasonally throughout southeastern Alaska from 1998 to 2006. An estimated 81,939 Pacific sand lances were captured at 31 of 49 locations and in 109 of 610 seine hauls. Total catch and percent frequency of occurrence (FO; [number of seine hauls with Pacific sand lances/total number of hauls] × 100) was greatest in summer (73,033 fish, FO = 21%), followed by spring (8,857 fish, 18%) and winter (49 fish, 1%). Pacific sand lances were captured in all habitat types; total catch in spring ranged from 16 fish in understory kelp (e.g., Laminariales) to 8,525 fish in bedrock outcrops, whereas total catch in summer ranged from 5,858 fish in sand to 54,851 fish in eelgrass Zostera marina. The FO was relatively consistent among the above habitat types and ranged from 15% to 20% in spring and from 15% to 35% in summer. Pacific sand lances use a variety of shallow‐water habitats for at least 4 months in spring and summer; habitat is not limited to sandy substrates for burrowing but also includes bedrock, eelgrass, and kelp as likely foraging areas. Age‐1 and younger Pacific sand lances dominated our catches; size range of captured fish was 39‐168 mm fork length. The importance of Pacific sand lances in the diets of other fishes, seabirds, and marine mammals justifies the need to better understand, protect, and manage habitats that are essential to Pacific sand lances.
Contaminated suspended sediments toxic to an Antarctic filter feeder: Aqueous- and particulate-phase effects
Authors: Hill Nicole A. , King Catherine K. , Perrett Lisa A. , Johnston Emma L. 
Published: September 2008

Abstract
Disturbances such as dredging, storms, and bioturbation result in the resuspension of sediments. This may affect sessile organisms that live on hard substrates directly above the sediment. Localized sediment contamination exists around many Antarctic research stations, often resulting in elevated contamination loads in marine sediments. To our knowledge, the potential impact of resuspended contaminated sediments on sessile fauna has not been considered, so in the present study, we assessed the sensitivity of Antarctic spirorbid polychaetes to aqueous metals and to metal-contaminated sediments that had been experimentally resuspended. Worms were first exposed to aqueous metals, both singly and in combination, over 10 d. Spirorbid mortality was tolerant to copper (median lethal concentration [LC50], 570 μg/L), zinc (LC50, &gt;4,910 μg/L), and lead (LC50, &gt;2,905 μg/L); however, spirorbid behavior responded to copper concentrations as low as 20μg/L. When in combination, zinc significantly reduced mortality caused by copper. A novel technique was used to resuspend sediments spiked with four concentrations of three metals (up to 450 μg/g dry wt of copper, 525 μg/g dry wt of lead, and 2,035 μg/g dry wt of zinc). The response of spirorbids to unfiltered suspended sediment solutions and filtered solutions (aqueous metal exposure) was measured. Suspended sediments were toxic to filter-feeding spirorbids at concentrations approximating those found in contaminated Antarctica areas. Toxicity resulted both from aqueous metals and from metals associated with the suspended sediments, although suspended clean sediments had no impact. To our knowledge, the present study is the first to show that resuspension of contaminated sediments can be an important pathway for toxicity to Antarctic hard substrate organisms. Based on the present results, current sediment-quality guidelines used in the evaluation of Australian sediments may be applicable to Antarctic ecosystems.
Design and Implementation of Retention/Filtration Media for Sand Control
Authors: Underdown David R. , Hopkins Sam 
Published: September 2008

Summary
The factors that control the performance of sand-control screens that use woven metal mesh as the filter media (i.e., commonly called premium screens), are not, generally, well understood by the end user. The end user is told that premium sand-control screens use filter media such as Dutch, Dutch Twill, or a Reverse Dutch Twill woven metal mesh, and in some cases the manufacturer will promote the benefit of multiple layers of woven-metal-mesh filter in the screen to control the sand. All this information is interesting, but the end user really does not understand the significance of the information.
This paper presents the results of a study to evaluate the effect of different metal-mesh weaves on the performance (e.g., dirt holding capacity, and plugging tendency) of media commonly used in sand-control screens. The work also introduces a new approach to designing sand-control screens that use woven-metal-mesh material. The performance criteria used in the evaluation of different designs for the filter media include the control of solids and the impact of particle size distribution on the formation of plugging on the surface and in the filtration media. Laboratory testing demonstrates that use of a different type of construction of the retention/filtration media allows for greater performance than media currently used in premium sand-control screens.
The significance of the approach discussed in this paper is the ability to design and engineer a premium sand-control screen with a retention/filtration medium for a given particle size distribution of the formation that allows for maximum oil production and minimum solids production. Critical to the success of this approach to designing sand-control screens is the thorough evaluation/testing of multiple media types to create the "formation specific" design.
Remote Real-Time Well Monitoring and Model Updating Help Optimize Drilling Performance and Reduce Casing Strings
Authors: Goobie Roger B. , Tollefsen Ed , Noeth Sheila , Sayers Colin , den Boer Lennert , Hooyman Pat , Akinniranye Goke , Cooke Jay , Thomas Ron , Carter Edgar 
Published: September 2008

Summary
Remote real-time pore pressure monitoring using a combination of Logging-While-Drilling (LWD) services coupled with a predrill pore-pressure model reduces risk and cost by providing significant insight into wellbore stability and allowing for casing seat optimization. This paper presents the results of a shelf job in the Gulf of Mexico (GoM) that allowed an operator to drill successfully in a very tight hydraulic envelope and even eliminate a string of casing.
The uncertainty in the pore-pressure prediction ahead of the bit can be significantly reduced by model updating. The LWD measurements allow the predrill velocity-to-pore-pressure transforms to be updated while drilling using the velocities from the sonic tool and pressures from the LWD formation pressure tool. This calibrated transform is then applied to revise the predrill pore-pressure model while drilling, and thus provide an estimate ahead of the bit. In this case study, the predrill model used interval velocities extracted from a 3D mechanical earth model of the northern GoM based on velocities derived from checkshots and sonic logs. These velocity data were kriged to give a 3D velocity model over the entire northern GoM with uncertainty estimates.
Using state of the art LWD technologies, a new methodology was used to optimize drilling performance on a well in Vermillion Block 338. Continuously updated LWD annular pressure measurements effectively gauge wellbore pressures and help the driller rapidly intervene in pressure and/or geomechanical wellbore stability issues. A complete understanding of the hydraulic forces acting on a borehole can increase the rate of penetration, provide greater safety, minimize casing strings, reduce or eliminate kicks and formation fracturing, and allow faster and less expensive completions.
The techniques described in this paper using real-time measurements allowed the operator to extend both the 9 5/8-in. intermediate casing and 7 in. liner to TD. As a result, a critical casing string was pushed 1,287 ft deeper than planned and a pre-planned 5 in. liner eliminated. This saved casing expense, as well as slimhole drilling and completion costs.
Transport of Small Cuttings in Extended-Reach Drilling
Authors: Duan Mingqin , Miska Stefan , Yu Mengjiao , Takach Nicholas , Ahmed Ramadan , Zettner Claudia 
Published: September 2008

Summary
Field experience has shown that inefficient transport of small cuttings is a main factor for excessive drag and torque during extended-reach drilling; however, very little is known about the transport behavior of small cuttings. In this study, extensive experiments with three sizes of cuttings (0.45 to 3.3 mm) were conducted in a field-scale flow loop (8 in.×4.5 in., 100-ft long) to identify the main factors affecting small cuttings transport. The effects of cuttings size, drillpipe rotation, fluid rheology, flow rate, and hole inclination were investigated.
The results show significant differences in cuttings transport based on cuttings size. Smaller cuttings result in a higher cuttings concentration than larger cuttings in a horizontal annulus when tested with water. However, a lower concentration was achieved for smaller cuttings when 0.25-ppb polyanionic cellulose (PAC) solutions were used. Unlike the transport of large cuttings, which is mainly dominated by fluid flow rate, the key factors controlling small cuttings transport were found to be pipe rotation and fluid rheology. Improvement by pipe rotation in the transport efficiency of small cuttings is up to twice as large as the improvement in large cuttings transport. Compared with water, PAC solutions significantly improve smaller cuttings transport, while the transport of larger cuttings is only slightly enhanced.
Mathematical modeling was performed to develop correlations for cuttings concentration and bed height in an annulus for field applications. Predictions from a three-layer model previously developed for larger cuttings were also compared with experimental results. Differences (up to 80%) indicate the need for improving the frequently used three-layer model by including correlations specifically developed for small cuttings to get a better design of extended-reach drilling. This study is also useful for horizontal or high-angle well drilling and completion through sand reservoirs.
Design of Well Barriers To Combat Circulation Losses
Authors: Aadnoy Bernt S. , Belayneh Mesfin , Arriado Miguel , Flateboe Roar 
Published: September 2008

Summary
The paper summarizes a 10-year research program at the University of Stavanger in borehole fracturing and mud design. Novel fracturing cells and mud cells were built to better understand the mechanisms that lead to circulation losses. Numerous experiments were conducted using both oil- and water-based drilling fluids.
The paper presents a new mechanistic model for fracturing called "the elastoplastic-barrier model." It is different from other recent models, and it is verified with laboratory experiments. In simple terms, it defines optimal barrier filtrate loss to place particles in the loss zone, and the mechanical strength of the particles required to resist losses. Selected laboratory experiments are presented demonstrating that borehole fracturing resistance can be improved significantly by changing the mud composition.
While testing commercial lost-circulation-material (LCM) products, it was found that some worked well, some were poor, and some worked only in synergy with others. On the basis of these findings, the compostion of an optimal LCM pill will be presented. Nonpetroleum products also have been tested to search for improvements in mud design. One result is that calcium carbonate can be replaced with more-efficient materials. We also have shown that adding small amounts of carbon fiber has a positive effect.
This research has been conducted in close cooperation with major mud companies and operators. A field case is presented from a shallow field. The mud was designed and tested during operation at the laboratory of the University of Stavanger. The result was a clear increase in fracture pressure, resulting in a successful operation.