bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rigless Tubing Repair Using Permanent and Retrievable Straddles on the North Slope, Alaska
Authors: Julian J. Y. , Cismoski D. A. , Burton J. P. , Johns J. E. 
Published: February 2008

Summary
At Prudhoe Bay, Alaska, nonrig tubing repairs have become a viable alternative to rig workovers (RWOs). They provide economic remediation for wells with production tubing by "A" annulus communication. Electricline (EL)-set straddles can eliminate tubing communication at a significant cost savings. They are particularly attractive in areas in which RWO cost is significant, such as offshore, remote, or Arctic locations. The advantage of tubing-straddle repair over a conventional RWO is that there is no need to pull tubing, resulting in the well being returned to service faster. Typical straddle deployment costs are less than 5% of the costs for tubing replacement with an RWO. To date, 263 permanent and retrievable tubing straddles have been set in 181 wells at Prudhoe Bay.
This paper discusses the history of conventional tubing straddles at Prudhoe Bay and the recommended prestraddle diagnostics. The paper also provides a systematic approach for their design and deployment.
Auto, Natural, or In-Situ Gas-Lift Systems Explained
Authors: Vasper Adam 
Published: February 2008

Summary
The terms auto, natural, and in-situ gas lift all refer to artificial lift systems that use gas from a gas-bearing formation to gas lift a well. The gas lift gas is produced downhole and bled into the production tubing via an auto gas lift valve designed for gas operations.
The value of auto gas lift is probably easier to demonstrate than for other types of intelligent well because it provides a direct replacement for conventional gas lift equipment, compressors, and pipelines, and the ancillary equipment they require.
An estimated 60 auto gas lift systems have been installed at the time of writing of this paper, most of them in the Scandinavian sector of the North Sea. Several papers have discussed this technology, but so far none has presented a rigorous analysis or solution of the wells' production from a gas lift perspective.
This paper presents the basic theory behind auto gas lift and how to apply it. The components of the theory are well known and commonly used in nodal analysis and conventional gas lift design. Properly combining these components enables an auto gas lifted well's performance to be calculated and downhole equipment to be correctly sized and located.
Carbon Dioxide Efflux from Soil with Poultry Litter Applications in Conventional and Conservation Tillage Systems in Northern Alabama
Authors: Roberson T. , Reddy K. C. , Reddy S. S. , Nyakatawa E. Z. , Raper R. L. , Reeves D. W. , Lemunyon J. 
Published: February 2008

AbstractIncreased CO2 release from soils resulting from agricultural practices such as tillage has generated concerns about contributions to global warming. Maintaining current levels of soil C and/or sequestering additional C in soils are important mechanisms to reduce CO2 in the atmosphere through production agriculture. We conducted a study in northern Alabama from 2003 to 2006 to measure CO2 efflux and C storage in long‐term tilled and non‐tilled cotton (Gossypium hirsutum L.) plots receiving poultry litter or ammonium nitrate (AN). Treatments were established in 1996 on a Decatur silt loam (clayey, kaolinitic thermic, Typic Paleudults) and consisted of conventional‐tillage (CT), mulch‐tillage (MT), and no‐tillage (NT) systems with winter rye [Secale cereale (L.)] cover cropping and AN and poultry litter (PL) as nitrogen sources. Cotton was planted in 2003, 2004, and 2006. Corn was planted in 2005 as a rotation crop using a no‐till planter in all plots, and no fertilizer was applied. Poultry litter application resulted in higher CO2 emission from soil compared with AN application regardless of tillage system. In 2003 and 2006, CT (4.39 and 3.40 μmol m−2 s−1, respectively) and MT (4.17 and 3.39 μmol m−2 s−1, respectively) with PL at 100 kg N ha−1 (100 PLN) recorded significantly higher CO2 efflux compared with NT with 100 PLN (2.84 and 2.47 μmol m−2 s−1, respectively). Total soil C at 0‐ to 15‐cm depth was not affected by tillage but significantly increased with PL application and winter rye cover cropping. In general, cotton produced with NT conservation tillage in conjunction with PL and winter rye cover cropping reduced CO2 emissions and sequestered more soil C compared with control treatments.
Abundances and Flux Estimates of Volatile Organic Compounds from a Dairy Cowshed in Germany
Authors: Ngwabie Ngwa Martin , Schade Gunnar W. , Custer Thomas G. , Linke Stefan , Hinz Torsten 
Published: February 2008

AbstractAnimal husbandry and manure treatment have been specifically documented as significant sources of methane, ammonia, nitrous oxide, and particulate matter. Although volatile organic compounds (VOCs) are also produced, much less information exists concerning their impact. We report on chemical ionization mass spectrometry and photo‐acoustic spectroscopy measurements of mixing ratios of VOCs over a 2‐wk measurement period in a large cowshed at the Federal Agricultural Research Centre (FAL) in Mariensee, Germany. The high time resolution of these measurements enables insight into the sources of the emissions in a typical livestock management setting. During feeding hours and solid manure removal, large mixing ratio spikes of several VOCs were observed and correlated with simultaneous methane, carbon dioxide, and ammonia level enhancements. The subsequent decay of cowshed concentration due to passive cowshed ventilation was used to model emission rates, which were dominated by ethanol and acetic acid, followed by methanol. Correlations of VOC mixing ratios with methane or ammonia were also used to calculate cowshed emission factors and to estimate potential nationwide VOC emissions from dairy cows. The results ranged from around 0.1 Gg carbon per year (1 Gg = 109 g) for nonanal and dimethylsulfide, several Gg carbon per year for volatile fatty acids and methanol, to over 10 Gg carbon per year of emitted ethanol. While some estimates were not consistent between the two extrapolation methods, the results indicate that animal husbandry VOC emissions are dominated by oxygenated compounds and may be a nationally but not globally significant emission to the atmosphere.
Soil–Atmosphere Trace Gas Exchange in Semiarid and Arid Zones
Authors: Galbally Ian E. , Kirstine Wayne V. , Meyer C. P. (Mick) , Wang Ying Ping 
Published: February 2008

AbstractA review is presented on trace gas exchange of CH4, CO, N2O, and NOx arising from agriculture and natural sources in the world's semiarid and arid zones due to soil processes. These gases are important contributors to the radiative forcing and the chemistry of the atmosphere. Quantitative information is summarized from the available studies. Between 5 and 40% of the global soil–atmosphere exchange for these gases (CH4, CO, N2O, and NOx) may occur in semiarid and arid zones, but for each of these gases there are fewer than a dozen studies to support the individual estimates, and these are from a limited number of locations. Significant differences in the biophysical and chemical processes controlling these trace gas exchanges are identified through the comparison of semiarid and arid zones with the moist temperate or wet/dry savanna land regions. Therefore, there is a poorly quantified understanding of the contribution of these regions to the global trace gas cycles and atmospheric chemistry. More importantly, there is a poor understanding of the feedback between these exchanges, global change, and regional land use and air pollution issues. A set of research issues is presented.
Effects of Sodium Bisulfate on Alcohol, Amine, and Ammonia Emissions from Dairy Slurry
Authors: Sun Huawei , Pan Yuee , Zhao Yongjing , Jackson Wendi A. , Nuckles Lisa M. , Malkina Irina L. , Arteaga Veronica E. , Mitloehner Frank M. 
Published: February 2008

AbstractSodium bisulfate (SBS) is extensively used in the poultry industry to reduce ammonia and bacterial levels in litter. It is also used in the dairy industry to reduce bacterial counts in bedding and ammonia emissions, preventing environmental mastitis and calf respiratory stress. The present study measured the effect of SBS on the air emission of ammonia, amine, and alcohol from a dairy slurry mix. Amine flux was undetectable (<5 ng L−1) across treatments. Application of SBS decreased ammonia, methanol, and ethanol emissions from fresh dairy slurry. Ammonia emissions decreased with increasing levels of SBS treatment. The 3‐d average ammonia flux from the control (no SBS applied) and the three different SBS surface application levels of 0.125, 0.250, and 0.375 kg m−2were 513.4, 407.2, 294.8, and 204.5 mg h−1m−2, respectively. The ammonia emission reduction potentials were 0, 21, 43, and 60%, respectively. Methanol and ethanol emissions decreased with an increase in the amount of SBS applied. The 3‐d average methanol emissions were 223.7, 178.0, 131.6, and 87.0 mg h−1m−2for SBS surface application level of 0, 0.125, 0.250, and 0.375 kg m−2, with corresponding reduction potentials of 0, 20, 41, and 61, respectively. Similar emission reduction potentials of 0, 18, 35, and 58% were obtained for ethanol. Sodium bisulfate was shown to be effective in the mitigation of ammonia and alcohol emissions from fresh dairy slurry.
Ammonia Assessment from Agriculture: U.S. Status and Needs
Authors: Aneja Viney P. , Blunden Jessica , James Kristen , Schlesinger William H. , Knighton Raymond , Gilliam Wendell , Jennings Greg , Niyogi Dev , Cole Shawn 
Published: February 2008

AbstractRecent studies suggest that human activities accelerate the production of reactive nitrogen on a global scale. Increased nitrogen emissions may lead to environmental impacts including photochemical air pollution, reduced visibility, changes in biodiversity, and stratospheric ozone depletion. In the last 50 yr, emissions of ammonia (NH3), which is the most abundant form of reduced reactive nitrogen in the atmosphere, have significantly increased as a result of intensive agricultural management and greater livestock production in many developed countries. These agricultural production practices are increasingly subject to governmental regulations intended to protect air resources. It is therefore important that an accurate and robust agricultural emission factors database exist to provide valid scientific support of these regulations. This paper highlights some of the recent work that was presented at the 2006 Workshop on Agricultural Air Quality in Washington, D.C. regarding NH3 emissions estimates and emission factors from agricultural sources in the U.S. and Europe. In addition, several best management practices are explored as the scientific community attempts to maximize the beneficial use of reactive nitrogen while simultaneously minimizing negative environmental impacts.
Are Leaves that Fall from Imidacloprid‐Treated Maple Trees to Control Asian Longhorned Beetles Toxic to Non‐target Decomposer Organisms?
Authors: Kreutzweiser David P. , Good Kevin P. , Chartrand Derek T. , Scarr Taylor A. , Thompson Dean G. 
Published: February 2008

AbstractThe systemic insecticide imidacloprid may be applied to deciduous trees for control of the Asian longhorned beetle, an invasive wood‐boring insect. Senescent leaves falling from systemically treated trees contain imidacloprid concentrations that could pose a risk to natural decomposer organisms. We examined the effects of foliar imidacloprid concentrations on decomposer organisms by adding leaves from imidacloprid‐treated sugar maple trees to aquatic and terrestrial microcosms under controlled laboratory conditions. Imidacloprid in maple leaves at realistic field concentrations (3–11 mg kg−1) did not affect survival of aquatic leaf‐shredding insects or litter‐dwelling earthworms. However, adverse sublethal effects at these concentrations were detected. Feeding rates by aquatic insects and earthworms were reduced, leaf decomposition (mass loss) was decreased, measurable weight losses occurred among earthworms, and aquatic and terrestrial microbial decomposition activity was significantly inhibited. Results of this study suggest that sugar maple trees systemically treated with imidacloprid to control Asian longhorned beetles may yield senescent leaves with residue levels sufficient to reduce natural decomposition processes in aquatic and terrestrial environments through adverse effects on non‐target decomposer organisms.
Physical and Chemical Changes during Composting of Wood Chip–Bedded and Straw‐Bedded Beef Cattle Feedlot Manure
Authors: Larney Francis J. , Olson Andrew F. , Miller Jim J. , DeMaere Paul R. , Zvomuya Francis , McAllister Tim A. 
Published: February 2008

AbstractIn the 1990s, restrictions on incineration encouraged the forest industry in western Canada to develop new uses for their wood residuals by product. One such use was as a replacement for cereal straw bedding in southern Alberta's beef cattle (Bos taurus) feedlot industry. However, use of carbon (C)‐rich bedding, such as wood chips, had implications for subsequent composting of the feedlot manure, a practice that was being increasingly adopted. In a 3‐yr study, we compared composting of wood chip–bedded manure (WBM) and barley (Hordeum vulgare L.) straw‐bedded manure (SBM). There were no significant differences in temperature regimes of SBM and WBM, indicating similar rates of successful composting. Of 17 physical and chemical parameters, five showed significant (P < 0.10) differences due to bedding at the outset of composting (Day 0), and 11 showed significant differences at final sampling (Day 124). During composting (10 sampling times), seven parameters showed significant bedding effects, 16 showed significant time effects, and four showed a Bedding × Time interaction. Significantly lower (P < 0.10) losses of nitrogen (N) occurred with WBM (19%) compared with SBM (34%), which has positive implications for air quality and use as a soil amendment. Other advantages of WBM compost included significantly higher total C (333 vs. 210 kg Mg−1 for SBM) and inorganic N (1.3 vs. 1.0 kg Mg−1 for SBM) and significantly lower total phosphorus (4.5 vs. 5.3 kg Mg−1 for SBM). Our results showed that wood chip bedding should not be a problem for subsequent composting of the manure after pen cleaning. In combination with other benefits, our findings should encourage the adoption of wood chips over straw as a bedding choice for southern Alberta feedlots.
Visceral Adiposity, Not Abdominal Subcutaneous Fat Area, Is Associated With an Increase in Future Insulin Resistance in Japanese Americans
Authors: Hayashi Tomoshige , Boyko Edward J. , McNeely Marguerite J. , Leonetti Donna L. , Kahn Steven E. , Fujimoto Wilfred Y. 
Published: February 2008

OBJECTIVE—Visceral adiposity is generally considered to play a key role in the metabolic syndrome. We sought to determine whether greater visceral adiposity directly measured by computed tomography (CT) is associated with increased future insulin resistance independent of other adipose depots.RESEARCH DESIGN AND METHODS— We followed 306 nondiabetic Japanese Americans over 10–11 years. Baseline variables included BMI; waist circumference; and abdominal, thoracic, and thigh fat areas measured by CT. Total fat area was estimated by the sum of all of these fat areas. Visceral adiposity was measured as intra-abdominal fat area at the umbilicus level. Total subcutaneous fat area was defined as total fat area minus intra-abdominal fat area. Insulin resistance was evaluated by homeostasis model assessment for insulin resistance (HOMA-IR), fasting plasma insulin level, Matsuda index, and area under the oral glucose tolerance test curve (AUC) of insulin.RESULTS— Both baseline intra-abdominal fat area (P = 0.002) and HOMA-IR (P &lt; 0.001) were independently associated with increased HOMA-IR at 10–11 years in a multiple linear regression model after adjustment for abdominal subcutaneous fat area, age, sex, 2-h plasma glucose level, and incremental insulin response. Intra-abdominal fat area remained a significant predictor of increased HOMA-IR at 10–11 years even after adjustment for total subcutaneous fat area, total fat area, BMI, or waist circumference, but no other measure of CT-measured regional or total adiposity was significantly related with HOMA-IR at 10–11 years in models that contained intra-abdominal fat area. Similar results were obtained for predicting future fasting plasma insulin level, Matsuda index, and AUC of insulin.CONCLUSIONS— Greater visceral adiposity is associated with an increase in future insulin resistance.
Inhibition of Dipeptidyl Peptidase IV With Sitagliptin (MK0431) Prolongs Islet Graft Survival in Streptozotocin-Induced Diabetic Mice
Authors: Kim Su-Jin , Nian Cuilan , Doudet Doris J. , McIntosh Christopher H.S. 
Published: February 2008

OBJECTIVE—Dipeptidyl peptidase-IV (DPP-IV) inhibitors have been introduced as therapeutics for type 2 diabetes. They partially act by blocking degradation of the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), thus increasing circulating levels of active hormones. In addition to their insulinotropic actions, GLP-1 and GIP also promote β-cell proliferation and survival, and DPP-IV inhibitors exert similar effects in rodent type 2 diabetes models. The study objective was to establish whether DPP-IV inhibitor treatment prolonged survival of transplanted islets and to determine whether positron emission tomography (PET) was appropriate for quantifying the effect of inhibition on islet mass.
RESEARCH DESIGN & METHODS—Effects of the DPP-IV inhibitor MK0431 (sitagliptin) on glycemic control and functional islet mass in a streptozotocin (STZ)-induced type 1 diabetes mouse model were determined with metabolic studies and microPET imaging.
RESULTS—The type 1 diabetes mouse model exhibited elevated plasma DPP-IV levels that were substantially inhibited in mice on an MK0431 diet. Residual β-cell mass was extremely low in STZ-induced diabetic mice, and although active GLP-1 levels were increased by the MK0431 diet, there were no significant effects on glycemic control. After islet transplantation, mice fed normal diet rapidly lost their ability to regulate blood glucose, reflecting the suboptimal islet transplant. By contrast, the MK0431 group fully regulated blood glucose throughout the study, and PET imaging demonstrated a profound protective effect of MK0431 on islet graft size.
CONCLUSIONS—Treatment with a DPP-IV inhibitor can prolong islet graft retention in an animal model of type 1 diabetes.
Oscillating Glucose Is More Deleterious to Endothelial Function and Oxidative Stress Than Mean Glucose in Normal and Type 2 Diabetic Patients
Authors: Ceriello Antonio , Esposito Katherine , Piconi Ludovica , Ihnat Michael A. , Thorpe Jessica E. , Testa Roberto , Boemi Massimo , Giugliano Dario 
Published: February 2008

OBJECTIVE—To explore the possibility that oscillating glucose may outweigh A1C levels in determining the risk for cardiovascular diabetes complications.
RESEARCH DESIGN AND METHODS—A euinsulinemic hyperglycemic clamp at 5, 10, and 15 mmol/l glucose was given in increasing steps as a single “spike” or oscillating between basal and high levels over 24 h in normal subjects and type 2 diabetic patients. Flow-mediated dilatation, a marker of endothelial function, and plasma 3-nitrotyrosine and 24-h urinary excretion rates of free 8-iso PGF2α, two markers of oxidative stress, were measured over 48 h postclamp.
RESULTS—Glucose at two different levels (10 and 15 mmol/l) resulted in a concentration-dependent fasting blood glucose–independent induction of both endothelial dysfunction and oxidative stress in both normal and type 2 diabetic patients. Oscillating glucose between 5 and 15 mmol/l every 6 h for 24 h resulted in further significant increases in endothelial dysfunction and oxidative stress compared with either continuous 10 or 15 mmol/l glucose.
CONCLUSIONS—These data suggest that oscillating glucose can have more deleterious effects than constant high glucose on endothelial function and oxidative stress, two key players in favoring cardiovascular complications in diabetes. Concomitant vitamin C infusion can reverse this impairment.
Codes that attain minimum distance in every possible direction
Authors: Katona Gyula , Sali Attila , Schewe Klaus-Dieter 
Published: February 2008

Abstract
The following problem motivated by investigation of databases is studied. Let $$
\mathcal{C}
$$ be a q-ary code of length n with the properties that $$
\mathcal{C}
$$ has minimum distance at least n − k + 1, and for any set of k − 1 coordinates there exist two codewords that agree exactly there. Let f(q, k)be the maximum n for which such a code exists. f(q, k)is bounded by linear functions of k and q, and the exact values for special k and qare determined.
Topological groups and convex sets homeomorphic to non-separable Hilbert spaces
Authors: Banakh Taras , Zarichnyy Igor 
Published: February 2008

Abstract
Let X be a topological group or a convex set in a linear metric space. We prove that X is homeomorphic to (a manifold modeled on) an infinite-dimensional Hilbert space if and only if X is a completely metrizable absolute (neighborhood) retract with ω-LFAP, the countable locally finite approximation property. The latter means that for any open cover $$
\mathcal{U}
$$ of X there is a sequence of maps (f
n: X → X)nεgw
such that each f
n is $$
\mathcal{U}
$$-near to the identity map of X and the family {f
n(X)}n∈ω
is locally finite in X. Also we show that a metrizable space X of density dens(X) < $$
\mathfrak{d}
$$ is a Hilbert manifold if X has gw-LFAP and each closed subset A ⊂ X of density dens(A) < dens(X) is a Z
∞-set in X.
Explicit rational solutions of Knizhnik-Zamolodchikov equation
Authors: Sakhnovich Lev 
Published: February 2008

Abstract
We consider the Knizhnik-Zamolodchikov system of linear differential equations. The coefficients of this system are rational functions generated by elements of the symmetric group $$
\mathcal{S}_n
$$
n. We assume that parameter ρ = ±1. In previous paper [5] we proved that the fundamental solution of the corresponding KZ-equation is rational. Now we construct this solution in the explicit form.
The Effect of Interfacial Roughness on the Thin Film Morphology and Charge Transport of High‐Performance Polythiophenes
Authors: Jung Youngsuk , Kline R. Joseph , Fischer Daniel A. , Lin Eric K. , Heeney Martin , McCulloch Iain , DeLongchamp Dean M. 
Published: February 2008

AbstractWe control and vary the roughness of a dielectric upon which a high‐performance polymer semiconductor, poly(2,5‐bis(3‐alkylthiophen‐2‐yl)thieno[3,2‐b]thiophene) (pBTTT) is cast, to determine the effects of roughness on thin‐film microstructure and the performance of organic field‐effect transistors (OFETs). pBTTT forms large, well‐oriented terraced domains with high carrier mobility after it is cast upon flat, low‐surface‐energy substrates and heated to a mesophase. Upon dielectrics with root‐mean square (RMS) roughness greater than 0.5 nm, we find significant morphological changes in the pBTTT active layer and significant reductions in its charge carrier mobility. The pBTTT films on rough dielectrics exhibit significantly less order than those on smooth dielectrics through characterization with atomic force microscopy and X‐ray diffraction. This critical RMS roughness implies that there exists a condition at which the pBTTT domains no longer conform to the local nanometer‐scale curvature of the substrate.