bluuebunny/crossref_metadata_2025_split huggingface dataset:
CO2 Flooding the Elm Coulee Field
Authors: Shoaib Shehbaz , Hoffman B. Todd 
Published: April 2009

Abstract
The Elm Coulee Field has extremely low permeability for an oil reservoir (0.01 – 0.04 md), which has caused an unconventional approach to its development by drilling long horizontal wells and massively fracturing them. The primary recovery factor, however, remains very low, around 5-10%. Significant reserves are available for post-primary production, yet the low permeability value restricts the choices available; for example, water flooding results in low injectivity. CO2 flooding may prove to be the most suitable option; however, the performance of CO2 flooding in this type of reservoir is not well understood. Using this field as an example, this paper presents the effects of CO2 flooding horizontal wells in a tight oil reservoir where hydraulic fractures provide the main path for fluid flow.
To analyze the impact of CO2 flooding in the Elm Coulee Field, a sector of the field is selected for reservoir modeling. The sector is two miles by two miles and consists of six, single-lateral horizontal wells. Two different reservoir models are built for the sector: a primary recovery and a CO2 flood model. They are used to determine the additional recovery due to a CO2 flood. Furthermore, the CO2 flood model is executed with different scenarios to determine the best well locations and injection schemes.
The models demonstrate that CO2 flooding horizontal wells in Elm Coulee Field increases production. Comparison of vertical and horizontal injection techniques indicates continuous horizontal CO2 injection is more efficient; it yields higher injection rates, and it is also beneficial for long-term recovery. Focusing on horizontal injection, the best scenario involves the practice of drilling new injectors along with converting existing producers to injection wells. In order to satisfy production requirements, production wells can be drilled such that there is an injector between two producers. This type of arrangement on horizontal injection increases the field recovery factor by 16 % after eighteen years of injection. The increase associated with single-well cyclic injection treatment is only 1 %; but in the absence of continuous CO2 supply, this method may be applicable for increasing recovery from reservoirs similar to Elm Coulee Field.
This research project demonstrates the technical aspects of CO2 injection in the context of Elm Coulee Field, while the economics are not considered. Developing a CO2 flood in this field appears feasible; however, the price of oil and the cost of drilling or converting wells will affect which, if any, is the best option.
Production Analysis of Multiply Fractured Horizontal Wells
Authors: Gilbert J. V. , Barree R. D. 
Published: April 2009

Abstract
Fracturing of horizontal wells is responsible for increasing rates and reserves from many reservoirs. Determining the optimum number of treatments, spacing, and eventual completion efficiency is critical to the success of a horizontal well development. This paper details the production analysis techniques required to evaluate the completion efficiency of multiply-fractured horizontal wells. Analytically modeled responses will be compared with actual horizontal well data to verify the technique.
Horizontal, Near-Wellbore Stress Effects on Fracture Initiation
Authors: Roundtree Russell , Eberhard Mike , Barree Robert 
Published: April 2009

Abstract
Throughout the past decade, the number of horizontal wells drilled in the United States has continued to increase. Several fields currently being developed are only economical with the application of horizontal wells. One such area where this is the case is in the Bakken formation in the Williston Basin. In the Bakken, operators have used a variety of different completion methods ranging from multilateral, openhole wellbores to single lateral cemented liners. Regardless of the completion method, hydraulic fracturing is required for increased oil recovery. In the past two years, most operators have started to converge on running uncemented liners with external packers as the preferred completion method. The purpose of the external packers is to compartmentalize the wellbore for more efficient fracture stimulation, as demonstrated by Miller (2008).
As this type of completion becomes more common, three key questions should be addressed: (1) how does the fracture initiate in an open-annulus wellbore (transverse or longitudinal), (2) what is the affect of the packer type on the stress on the wellbore surrounding the packer, and (3) can any of this be used to help with fracture design, or does it even matter?
Finite-element modeling provides several advantages for modeling the different physical characteristics and responses for a system with very different sensitivities across the scale of the model. In the cases considered in this paper, the edge of the wellbore must be finely modeled to take into account the hoop stresses developed as a result of removing the rock volume from the original stress state. This is further complicated by the effects of orientation of the wellbore relative to the maximum and minimum horizontal stress and of different packers placed in the wellbore for isolation between stages.
Conclusions on fracture-initiation behavior based on typical wellbore geometries, physical-rock properties, in-situ stress scenarios, and common packers are presented in this paper.
Micro–macro linkages in institutional restructuring processes in the water sector: example of the operations management support project (OMS) in Jordan
Authors: Rothenberger Dieter , Meuss Marina , Stoll Uwe 
Published: April 2009

The German Agency for Technical Cooperation (GTZ) has supported the Water Authority of Jordan (WAJ) since 1994 by the provision of assistance aimed at increasing the efficiency of the potable water supply and wastewater disposal services under the Operations Management Support (OMS) project.
Using OMS as an example, this article shows the links of the change processes at the utility and the sector level (micro–macro linkages) for the introduction of institutional changes within the Jordanian water sector. The support of OMS followed co-evolutionary thinking, that is, it supported the dynamics coming from the utility level and affecting the sector level as well as the feedback loops from sector level to utility level. On the utility level, OMS activities and the induced improvements are a technical base for wider reform processes. They facilitated the implementation of private sector participation, PSP, with better quality base data. The information systems which were introduced by the project also indicated the importance of structural changes on the sector level and the urgency of these reforms. And finally, the involvement of OMS staff on the utility level made them credible when offering advice about the sector level. Hence, the parallel support of activities on both levels provided a deeper awareness of the reform issues and contributed to the success of the sector reforms.
The Effect of Salary Caps in Professional Team Sports on Social Welfare
Authors: Dietl Helmut M , Lang Markus , Rathke Alexander 
Published: April 2009

Abstract
This paper provides a theoretical model of a team sports league and studies the welfare effect of salary caps. It shows that salary caps will increase competitive balance and decrease overall salary payments within the league. The resulting effect on social welfare is counter-intuitive and depends on the preference of fans for aggregate talent and for competitive balance. A salary cap that binds only for large-market clubs will increase social welfare if fans prefer aggregate talent despite the fact that the salary cap will result in lower aggregate talent. If fans prefer competitive balance, on the other hand, any binding salary cap will reduce social welfare.
Force Decay of Elastomeric Ligatures: Influence onUnloading Force Compared to Self-Ligation
Authors: Petersen Alan , Rosenstein Sheldon , Kim Ki Beom , Israel Heidi 
Published: April 2009

Abstract
Objective: To compare elastomeric ligatures (EL) vs self-ligating (SL) brackets in terms of their effects on the unloading force of a 0.014-inch CuNiTi aligning wire.
Materials and Methods: By simulating the alignment of a lingually malposed canine and using a full-arch design, three ligation methods—SL, EL, and “relaxed” elastomeric ligature (REL)— were tested with 30 wires per group. Each test was conducted in a dry field within a Plexiglas case at 35 ± 2°C. Eleven brackets were affixed from first molar to first molar site on a steel plate with a space created at the location of the left canine. The wire was deflected 3 mm then was unloaded at a speed of 2 mm per minute. Data were gathered from four points along the unloading plot generated during each test and then were compared by using the Kruskal-Wallis one-way analysis of variance. Mann-Whitney tests were used to compare combinations of groups.
Results: Wires ligated with EL and REL produced an average unloading force equal to 56% and 88%, respectively, of the same wire in an SL bracket.
Conclusions: The unloading forces produced by a wire after force decay of the elastomers are not statistically different from the forces present in self-ligating systems.
Effects of the Taper Shape, Dual-Thread, and Length on the Mechanical Properties of Mini-Implants
Authors: Kim Young-Kyun , Kim Yoon-Ji , Yun Pil-Young , Kim Jong-Wan 
Published: April 2009

Abstract
Objective: To analyze the mechanical effects of the length and the various shapes such as cylindrical shape, taper shape, and dual-thread shape on the insertion and removal torque of mini-implants.
Materials and Methods: Mini-implants (diameter 1.6 mm and length 6 mm and 8 mm) consisting of cylindrical, taper, and dual-thread groups were inserted and removed in Sawbones while measuring the torque and time. Mechanical analysis was done of maximum insertion torque (MIT), maximum removal torque (MRT), torque ratio (TR; MRT/MIT), insertion angular momentum (IAM), removal angular momentum (RAM), and time of MIT. Measurements were statistically evaluated to analyze any differences of shapes and lengths.
Results: The cylindrical shape had the lowest MIT and MRT in each length. Although taper shape showed the highest MIT in each length, dual-thread shape showed significantly higher MRT, TR, and RAM in each length (P &lt; .05). Dual-thread groups showed a gentle increase of insertion torque and a gentle decrease of removal torque in contrast to the other shape groups. However, it had higher IAM and time of MIT. The long length group showed significantly higher measurements except for TR.
Conclusions: Dual-thread shape provided better mechanical stability with high removal torque on the broad range than other shapes. However, dual-thread shape may need improvement for reducing the long insertion time to decrease the stress to the surrounding tissue.
Effects of CPP-ACP Paste on the Shear Bond Strength of Orthodontic Brackets
Authors: Xiaojun Ding , Jing Lu , Xuehua Guo , Hong Ruan , Youcheng Yu , Zhangyu Gu , Sun Jian 
Published: April 2009

AbstractObjective: To evaluate the effect of casein phosphopeptide–amorphous calcium phosphate (CPP-ACP) paste on shear bond strength and debonding failure modes of orthodontic brackets.Materials and Methods: Freshly extracted premolars were randomly divided into four groups (n =18) as follows: in groups 1 and 3, the enamel was treated with a solution of CPP-ACP dissolved in artificial saliva; groups 2 and 4 served as controls, and the enamel was treated with artificial saliva. After conventional acid etching, in groups 1 and 2, brackets were bonded using a light-cured bonding system (Blugloo); while in groups 3 and 4, brackets were bonded using a conventional bonding system (Unite Bonding Adhesive). Bonded specimens were subjected to thermal cycling for 1000 cycles before debonding procedures. After debonding, teeth and brackets were examined under a stereomicroscope at 10× magnification to determine whether any adhesive remained, in accordance with the adhesive remnant index. The acid-etched enamel surfaces were also observed using scanning electron microscopy after treatment with and without CPP-ACP paste.Results: The shear bond strengths of group 1 were significantly higher than those seen in group 2 (P &lt; .01). There was no significant difference in the shear bond strengths of groups 3 and 4 (P &gt; .05). Scanning electron microscopic observation showed that the pretreated enamel surface was rougher than that of the control surface after acid etching.Conclusion: The use of CPP-ACP can be considered as an alternative prophylactic application in orthodontic practice since it did not compromise bracket bond strength.
Lip Vermilion Profile Patterns and Corresponding Dentoskeletal Forms in Female Adults
Authors: Tanikawa Chihiro , Nakamura Kayoko , Yagi Masakuzu , Takada Kenji 
Published: April 2009

Abstract
Objectives: To objectively classify shapes of the human lip vermilion in the lateral view, and to examine whether any morphologic characteristics of dentoskeletal patterns are specific to each classified lip profile pattern.
Materials and Methods: Pretreatment, lateral facial photographs of 234 Japanese women were selected. Investigators with expert knowledge of the anatomic traits of the lip vermilion in the lateral view extracted from images of the face a 13-dimensional feature vector that represented lip vermilion profile shapes. The vector quantization technique was applied to the feature vectors to mathematically optimize the number of lip vermilion profile patterns. Dentoskeletal patterns that corresponded to each classified lip shape were compared statistically.
Results: Seven patterns were found, and differences between patterns were notably maximized by the flatness of the anterior portion of the lip vermilion for the upper and lower lip, the position of the most protruded point of the lip vermilion, lip fissure inclination, and differences between the horizontal positions of the upper and lower lip vermilions. The dentoskeletal forms showed significant differences between classified lip vermilion profile patterns (P &lt; .01).
Conclusions: (1) Vector quantization revealed that classifying lip vermilion profiles into seven representative patterns was optimal for maximizing differences in the configuration of the lip vermilion. (2) Lip vermilion profile shapes were found to be associated with horizontal lengths of the anterior cranial base, horizontal/vertical positions, inclination and length of the mandible, and horizontal positions and labio-lingual inclinations of the upper and lower incisors.
Stimulation of Bone Formation by Dietary Boron in an Orthopedically Expanded Suture in Rabbits
Authors: Uysal Tancan , Ustdal Ayca , Sonmez Mehmet Fatih , Ozturk Figen 
Published: April 2009

AbstractObjective: To evaluate the effects of dietary boron on bone regeneration in rabbits in response to expansion of the midpalatal suture during different retention periods.Materials and Methods: Twenty-eight 12-week-old New Zealand white male rabbits were separated into four equal groups: group 1 (B+10) and group 2 (B−10) had retention periods of 10 days with or without boron intake, respectively. Group 3 (B+20, with boron) and group 4 (B−20, without boron) were retained for 20 days. All groups had a 5-day expansion period. For both B+ groups, boron was prepared in distilled water and given to the rabbits during their (1) nursery phase (40 days), (2) expansion phase, and (3) retention period at a dosage of 3 mg/kg daily by oral gavage. Bone regeneration in the midpalatal suture was evaluated by a bone histomorphometric method, and the mineralized area (Md.Ar), fibrosis area (Fb.Ar), mineralized area/fibrosis area (Md.Ar/Fb.Ar), bone area (B.Ar) and osteoblast number (N.Ob) parameters were evaluated.Results: Statistical analysis showed significant differences between groups for all investigated measurements. Md.Ar (P &lt; .01), Md.Ar/Fb.Ar (P &lt; .001), B.Ar (P &lt; .01), and N.Ob (P &lt; .01) parameters were increased and Fb.Ar (P &lt; .01) was decreased in groups B+10 and B+20. No significant differences were observed during an additional 10-day retention period in all groups (P &lt; .05).Conclusions: Boron has a positive effect on the early phase of bone regeneration of the midpalatal suture in response to expansion and may be beneficial in routine maxillary expansion procedures.
Elevated MBL Concentrations Are Not an Indication of Association Between the MBL2 Gene and Type 1 Diabetes or Diabetic Nephropathy
Authors: Kaunisto Mari A. , Sjölind Lisa , Sallinen Riitta , Pettersson-Fernholm Kim , Saraheimo Markku , Fröjdö Sara , Forsblom Carol , Fagerudd Johan , Hansen Troels K. , Flyvbjerg Allan , Wessman Maija , Groop Per-Henrik ,   for the FinnDiane Study Group
Published: April 2009

OBJECTIVE
Mannose-binding lectin (MBL) is an essential component of the acute-phase immune response and may thus play a role in the pathogenesis of type 1 diabetes and diabetic nephropathy. The serum concentration of MBL is mainly genetically determined, and elevated concentrations have been associated with both type 1 diabetes and diabetic nephropathy. Previous genetic studies have not been conclusive due to the small number of patients and polymorphisms studied. We investigated whether MBL2 polymorphisms are associated with type 1 diabetes or diabetic nephropathy and whether patients with nephropathy have elevated MBL concentrations as indicated previously. Furthermore, we studied the association between MBL2 polymorphisms and MBL concentration.

RESEARCH DESIGN AND METHODS
We genotyped 20 MBL2 single nucleotide polymorphisms (SNPs) in a large, well-characterized Finnish case-control sample consisting of 1,297 patients with type 1 diabetes with or without nephropathy and 701 nondiabetic individuals. The serum concentration of MBL was available for 1,064 patients.

RESULTS
We found that 19 SNPs were associated with the MBL concentration (P = 3 × 10−81–7 × 10−4). MBL concentrations were higher in patients with macroalbuminuria compared with patients without nephropathy even when the patients were stratified by the MBL2 genotypic background in accordance with previous studies. However, no evidence of association between any of the SNPs or their haplotype combinations and type 1 diabetes or diabetic nephropathy was observed.

CONCLUSIONS
Although most of the MBL2 SNPs studied were associated with the MBL concentration, no common variations (neither single SNPs nor their haplotype combinations) confer risk of type 1 diabetes or diabetic nephropathy.
Butyrate Improves Insulin Sensitivity and Increases Energy Expenditure in Mice
Authors: Gao Zhanguo , Yin Jun , Zhang Jin , Ward Robert E. , Martin Roy J. , Lefevre Michael , Cefalu William T. , Ye Jianping 
Published: April 2009

OBJECTIVE
We examined the role of butyric acid, a short-chain fatty acid formed by fermentation in the large intestine, in the regulation of insulin sensitivity in mice fed a high-fat diet.

RESEARCH DESIGN AND METHODS
In dietary-obese C57BL/6J mice, sodium butyrate was administrated through diet supplementation at 5% wt/wt in the high-fat diet. Insulin sensitivity was examined with insulin tolerance testing and homeostasis model assessment for insulin resistance. Energy metabolism was monitored in a metabolic chamber. Mitochondrial function was investigated in brown adipocytes and skeletal muscle in the mice.

RESULTS
On the high-fat diet, supplementation of butyrate prevented development of insulin resistance and obesity in C57BL/6 mice. Fasting blood glucose, fasting insulin, and insulin tolerance were all preserved in the treated mice. Body fat content was maintained at 10% without a reduction in food intake. Adaptive thermogenesis and fatty acid oxidation were enhanced. An increase in mitochondrial function and biogenesis was observed in skeletal muscle and brown fat. The type I fiber was enriched in skeletal muscle. Peroxisome proliferator–activated receptor-γ coactivator-1α expression was elevated at mRNA and protein levels. AMP kinase and p38 activities were elevated. In the obese mice, supplementation of butyrate led to an increase in insulin sensitivity and a reduction in adiposity.

CONCLUSIONS
Dietary supplementation of butyrate can prevent and treat diet-induced insulin resistance in mouse. The mechanism of butyrate action is related to promotion of energy expenditure and induction of mitochondria function.
Metabolic Syndrome and Diabetes, Alone and in Combination, as Predictors of Cardiovascular Disease Mortality Among Men
Authors: Church Timothy S. , Thompson Angela M. , Katzmarzyk Peter T. , Sui Xuemei , Johannsen Neil , Earnest Conrad P. , Blair Steven N. 
Published: April 2009

OBJECTIVE
To examine cardiovascular disease (CVD) mortality risk in men with diabetes only, metabolic syndrome only, and concurrent metabolic syndrome and diabetes.

RESEARCH DESIGN AND METHODS
We examined CVD mortality risk by metabolic syndrome and diabetes status in men from the Aerobics Center Longitudinal Study (ACLS) (mean ± SD age 45.1 ± 10.2 years). Participants were categorized as having neither diabetes nor metabolic syndrome (n = 23,770), metabolic syndrome only (n = 8,780), diabetes only (n = 532), or both (n = 1,097). The duration of follow-up was 14.6 ± 7.0 years with a total of 483,079 person-years of exposure and 1,085 CVD deaths.

RESULTS
Age-, examination year–, and smoking-adjusted CVD death rates (per 1,000 man-years) in men with neither metabolic syndrome nor diabetes, metabolic syndrome only, diabetes only, and both were 1.9, 3.3, 5.5, and 6.5, respectively. CVD mortality was higher in men with metabolic syndrome only (hazard ratio 1.8 [95% CI 1.5–2.0]), diabetes only (2.9 [2.1–4.0]), and both (3.4 [2.8–4.2]) compared with men with neither. The presence of metabolic syndrome was not associated (1.2 [0.8–1.7]) with higher CVD mortality risk in individuals with diabetes. In contrast, the presence of diabetes substantially increased (2.1 [1.7–2.6]) CVD mortality risk in individuals with metabolic syndrome.

CONCLUSIONS
The presence of diabetes was associated with a threefold higher CVD mortality risk, and metabolic syndrome status did not modify this risk. Our findings support the fact that physicians should be aggressive in using CVD risk–reducing therapies in all diabetic patients regardless of metabolic syndrome status.