bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterologous influenza vRNA segments with identical non-coding sequences stimulate viral RNA replication in trans
Authors: Ng Stella SF , Li Olive TW , Cheung Timothy KW , Malik Peiris J S , Poon Leo LM 
Published: January 2008

Abstract
The initiation of transcription and replication of influenza A virus requires the 5' and 3' ends of vRNA. Here, the role of segment-specific non-coding sequences of influenza A virus on viral RNA synthesis was studied. Recombinant viruses, with the nonstructural protein (NS) segment-specific non-coding sequences replaced by the corresponding sequences of the neuraminidase (NA) segment, were characterized. The NS and NA vRNA levels in cells infected with these mutants were much higher than those of the wild type, whereas the NS and NA mRNA levels of the mutants were comparable to the wild-type levels. By contrast, the PB2 vRNA and mRNA levels of all the tested viruses were similar, indicating that vRNA with heterologous segment-specific non-coding sequences was not affected by the mutations. The observations suggested that, with the cooperation between the homologous 5' and 3'segment-specific sequences, the introduced mutations could specifically enhance the replication of NA and NS vRNA.
Broad network-based predictability of Saccharomyces cerevisiaegene loss-of-function phenotypes
Authors: McGary Kriston L , Lee Insuk , Marcotte Edward M 
Published: January 2008

AbstractWe demonstrate that loss-of-function yeast phenotypes are predictable by guilt-by-association in functional gene networks. Testing 1,102 loss-of-function phenotypes from genome-wide assays of yeast reveals predictability of diverse phenotypes, spanning cellular morphology, growth, metabolism, and quantitative cell shape features. We apply the method to extend a genome-wide screen by predicting, then verifying, genes whose disruption elongates yeast cells, and to predict human disease genes. To facilitate network-guided screens, a web server is available http://www.yeastnet.org.
Stereochemical effects on intervalence charge transfer
Authors: D'Alessandro Deanna M. , Keene F. Richard 
Published: January 2008

Abstract
Recent work has revealed the first observation of stereochemical effects on intervalence charge transfer (IVCT) in di- and trinuclear mixed-valence complexes. The differential IVCT characteristics of the diastereoisomers of polypyridyl complexes of ruthenium and osmium offer a new and intimate probe of the fundamental factors that govern the extent of electronic delocalization and the barrier to electron transfer. These findings challenge prior assertions that the inherent stereochemical identity of such complexes would have no influence on the intramolecular electron-transfer properties of polymetallic assemblies. This article provides a brief review of the past 40 years of mixed-valence research and looks at recent progress in stereochemical effects on IVCT. The implications of the findings are considered within the context of the existing theoretical and experimental framework for IVCT.
Quest for the ideal olefin metathesis catalyst
Authors: Michrowska Anna , Grela Karol 
Published: January 2008

AbstractAttempts were made to create a catalyst that approaches Gladysz's vision of an "ideal catalyst". Modifications of the Hoveyda-Grubbs catalyst were carried out with the aim to increase its activity and broaden the scope of its applicability to challenging metathesis reactions. This was done by introduction of an electron-withdrawing substituent on the isopropoxybenzylidene group in order to diminish the donor properties of the oxygen atom. The resulting stable and easily accessible nitro-substituted Hoveyda-Grubbs catalyst has found a number of successful applications in various research and industrial laboratories. Also, a new concept for noncovalent immobilization of a ruthenium olefin metathesis catalyst is presented. The 2-isopropoxybenzylidene ligand of Hoveyda-Grubbs carbene is further modified by an additional amino group, and immobilization is achieved by treatment with sulfonated polystyrene, forming the corresponding ammonium salt. In this novel strategy for the immobilization of ruthenium-based metathesis catalysts, the amino group plays a dual role, being first an active anchor for immobilization and secondly, after protonation, activating the catalysts by electron-donating to -withdrawing switch. The same concept has been used in the preparation of a quaternary ammonium catalyst for aqueous olefin metathesis.
Tribochemistry of Multiply Alkylated Cyclopentane Oils on Diamond-like Carbon (DLC) Coated Thrust Bearings
Authors: Lince Jeffrey R. , Bertrand Patricia A. , Eryilmaz Osman L. , Erdemir Ali 
Published: January 2008

Abstract
In contrast to typical diamond-like carbon (DLC) coatings, hydrogenated DLC (H-DLC) coatings have demonstrated extremely low friction in vacuum and dry atmospheres. This behavior suggests the coatings’ potential importance for spacecraft applications. However, most studies have concentrated on sliding wear testing, with relatively few concerning their use on ball bearings. We have conducted a preliminary study of H-DLC-coated steel thrust bearings, lubricated with a multiply alkylated cyclopentane (MAC) oil, either unformulated (NSO2001A), or formulated with lead naphthenate (Pbnp) or an aryl phosphate ester mixture (NSO2001). To determine if the additives could provide life enhancement when using H-DLC coatings, post-test analyses of the bearing surfaces were conducted using electron microscopy and Auger electron spectroscopy, and analysis of the residual lubricant was conducted using Fourier-transform infrared spectroscopy. Minimal additive-based tribofilm formation was detected on the surfaces of the H-DLC coatings in the wear tracks relative to that with steels. For example, using Pbnp resulted in considerably thicker Pb-containing tribofilms on the uncoated bearing surfaces compared to the H-DLC-coated surfaces. The results indicate that additives suitable for steels may not be appropriate for H-DLC coatings. The high roughness of the bearings used in this study contributed to local spallation of H-DLC at asperities in the wear track. When tested with NSO2001 or NSO2001A oil, several H-DLC-coated bearings endured for significantly longer than uncoated bearings (&gt;10 Mcycles) tested with the same oils. However, the variation and magnitude of the bearing roughness contributed to statistical uncertainty regarding the endurance enhancement of H-DLC coatings. Future studies are planned with higher quality bearings.
Application of Rotary Steerable System/PDC Bits in Hard Interbedded Formations: A Multidisciplinary Team Approach to Performance Improvement
Authors: Fiksdal Harald , Hydro Norsk , Rayton Clive , Djerfi Zvonimir 
Published: January 2008

Abstract
The Sognefjord reservoir (Jurassic) in Troll Field, Norwegian North Sea, is drilled horizontally in 9½" hole from 1,800 m to 3,100 m in length. The reservoir consists of loose sands, subdivided into clean and micaceous units and local hard calcareous cemented zones. These sections must be drilled in a tight horizontal plane, approximately one meter above the oil-water contact to maximize oil production. The oil bearing strata is typically between 12 m and 27 m thick. Most steering is done in the vertical plane to keep the well within the narrow target window (∼1 m TVD or less) and in the optimum azimuth to place the well in the desired reservoir sand.
Historically this section has been drilled with steerable motor assemblies and tungsten carbide insert roller cone bits. The use of polycrystalline diamond compact (PDC) bits was precluded due to problems associated with toolface control in the loose sands. With the advent of a rotary steerable tool (RSS) came the prospect of long runs with specialized PDC bits. After major area specific problems were encountered a joint task force was assembled, consisting of a drilling operator and an integrated service company, to attempt to improve drilling performance in the reservoir section.
Three main areas of potential improvement were identified:
Improve reliability of the RSS (including MWD). Increased ROP in hard calcite cemented sandstones. Mapping and prediction of calcite cemented zones.
The team concentrated on rock strength analysis, simulator testing of new PDC designs, BHA vibration modeling and analysis of depth based drilling, MWD & vibration data. Modified BHA's and Troll specific antiwhirl PDC bits, along with revised drilling practices, were applied in the field. This allowed step improvements in drilling performance to be achieved. Overall, meters/BHA increased from 264 m to ∼640 m. The new bit designs also increased the overall average R from ∼10 to 20 m/hr and improved instantaneous ROP in the calcareous sandstone sections. Savings in rig time on the Troll development are potentially immense as approximately 60 wells remain to be drilled.
This paper will highlight the need for a systematic approach, including problem definition, data collection, solutions implementation and results benchmarking.
Square Motor Used to Reduce Drag while Maximizing Penetration Rates
Authors: Moore R. S. , Barnett R. T. , Smith T. R. 
Published: January 2008

Abstract
Extended power section motors have been used, together with low-viscosity muds; to dramatically increase instantaneous penetration rates in tectonically stressed areas of Western Canada. However, these penetration rate increases have been accompanied by doglegs induced by steep formation dips and faulting. Steering, required to remain on course, induces further doglegs. The result of such a tortuous wellpath has been high drag. In order to reduce the drag, motor drilled holes have been reamed on time consuming, dedicated trips made with square drill collars.
A square motor has been developed to combine the penetration rate benefits of extended power section mud motors with the stiffness characteristics of a square drill collar. The square motor has been used in the drilling of wells in a number of tectonically stressed fields, and has demonstrated:
Instantaneous penetration rates equal to or better than those obtained with conventional (round) motors Reliable directional characteristics, especially given the tectonically stressed state of the formations being drilled Significant reduction in drag when tangent sections are drilled with square motors rather than steered with directional motors Elimination of reaming time through square motor drilled intervals
Bi-Center Innovations Impact Deepwater Drilling
Authors: Denham Dubby , Fielder Coy M. 
Published: January 2008

Abstract
In 1994, bi-center bits were introduced which contained new technology. For the first time, a single tool could reliably be used to simultaneously drill and underream, even in highly directional applications, all with no moving parts. The results were fewer trips, fewer rotating hours, and less "problem" time. The only major draw back to using bi-center bits has been that they could not be used to drill out cement, float equipment, and casing guide shoes. It was required that a conventional drill bit be used first to drill out into new formation, then a trip was needed to pick up the bi-center bit.
In 1999, advancements in bi-center technology have resulted in a bi-center bit that can be used to drill out and then continue to drill ahead. At the same time ROP, directional control, and hole quality have also improved.
On the first field test of this new technology, bi-centers were used to drill out and drill ahead on three consecutive intervals of a deepwater Gulf of Mexico well. The intervals included a vertical section, a build section, and a tangent section. In all three cases, the drill out was performed with results similar to offset PDC bits, directional targets were all hit with no steering difficulties encountered, and in all three sections, the casing or liner was run to bottom with no problems. The cost savings in trip time alone amounted to over $560,000 (5 trips eliminated). This paper describes the new technology and gives details on the performance (drilling out and in the formation) which lead to the cost savings.
The Development of a Light Well Intervention Ship
Authors: Willis S. K. , Campbell J. A. S. 
Published: January 2008

Abstract
The number of sub sea wells in the world has increased greatly in the last few years. It is estimated that there are approximately 750 sub sea wells in the North Sea with many more than this number world wide. All the indications are that the number of sub sea wells will continue to increase as operators exploit this proven technology in ever deeper water depths. The cost effectiveness of sub sea completions with floating production facilities combined with the environmental advantages of not installing large fixed platforms means that the number of subsea developments will continue to grow.
Coiled tubing as a means of well intervention has matured considerably over the last five years with coiled tubing performing operations that previously would have been the preserve of workover rigs or hydraulic workover units. These two developments lead to the inescapable conclusion that a light subsea well intervention vessel equipped with coiled tubing as it’s primary means of intervention could offer a cost effective method of working over sub sea wells.
Sub-sea well workover is an essential part of field maintenance. It can be divided into two categories; Heavy workover where there is a requirement to deploy a marine drilling riser to retrieve the down hole completion string, necessitating the use of the full capabilities of a drilling rig,Light intervention that can be performed through the existing completion using coiled tubing or wire line requiring a light riser or a sub sea riser.
Light well intervention is currently carried out by mobilising portable equipment onto semi-submersible drill rigs. These rigs may be diverted from infield drilling, or spot hired for the task. Well intervention therefore tends to be performed only when deteriorating well performance has become critical and it can no longer be avoided.
With the growing inventory of sub-sea wells, the industry has recognised the need for a more cost effective, efficient and comprehensive ability to intervene in, and maintain, sub-sea wells. Previous industry studies have concluded that a semi-submersible would be too expensive, and that the motion characteristics of known monohulls would necessitate shut in and disconnection of the riser in relatively modest sea states. Thus both options were seen to be uncompetitive, and the decision to design a new ship was taken.
Using Alumni Research to Assess a Veterinary Curriculum and Alumni Employment and Reward Patterns
Authors: Bristol David G. 
Published: January 2008

Rationale for the study – The purpose of the study was to obtain an outcomes assessment of the professional degree program of a veterinary college and to determine whether recently published national gender differences were true for a program that has always been predominantly female. Methodology – A survey was developed and mailed to all alumni of the veterinary degree program at North Carolina State University. Anonymous responses were collected by an independent organization for summation. Results were expressed numerically where possible, although the survey included numerous opportunities for textual responses. Responses were stratified by year of graduation, in five-year increments, and by gender of the respondents. Results 1. Sixty-one percent of graduates remained within North Carolina. 2. While most of the prerequisite courses were considered useful preparation for the curriculum, physics and calculus were exceptions. 3. Over half the alumni thought time allocations to specific courses were appropriate. However, there were substantial differences between courses. 4. The alumni were satisfied with most aspects of the training program, although there were differences between various components. 5. There were substantial gender differences in length of first employment, salaries, species treated, practice ownership and type of ownership, and career satisfaction. 6. Most alumni work in small animal private clinical practice. Ninety-four percent were employed within three months of graduating. Ninety-five percent did no work with the state’s predominant agricultural species. 7. Nineteen percent of alumni were either unsure, probably would not, or definitely would not become a veterinarian if they could choose again. Conclusion – The survey was a tremendously valuable source of information. Results provided support for curricular revision. The survey also provided comparative data in relation to national norms, where such norms were available. Unfortunately, few reports of this type are available, making inter-institutional comparisons difficult. The Association of American Veterinary Medical Colleges could assist with standardizing the process of outcomes assessment.
Group Learning Improves Case Analysis in Veterinary Medicine
Authors: Pickrell John A. , Boyer John , Oehme Frederick W. , Clegg Victoria L. , Sells Nikki 
Published: January 2008

Introduction – Group learning has become important to professional students in the healing sciences. Groups share factual and procedural resources to enhance their performances. Methodology – We investigated the extent to which students analyzing case-based evaluations as teams acquired an immediate performance advantage relative to those analyzing them as individuals and the extent to which group work on one problem led to better performance by individual students on related problems. We blinded written evaluations by randomly assigning numbers to groups of students and using removable tracers. Differences between groups and individuals were evaluated using Student’s t statistic. Similar comparisons were evaluated by meta-analysis to determine overall trends. Results – Students who analyzed evaluations as a group had an 8.5% performance advantage over those who analyzed them as individuals. When evaluations were divided into those asking questions related to treatment, differential diagnosis, and prognosis, specific performance advantages for groups relative to individuals were 8.9%, 5.9%, and 6.1% respectively. Students who had previously been trained by group evaluations had a 1.5% advantage relative to those who received their training as individuals. Conclusions – Answers by students analyzing evaluations as groups suggested a deeper understanding, in large part because of their improved ability to explain treatment and to conduct differential diagnosis. These improvements suggested limited abilities to use previous experience to improve present performance.
The Demographics and Evaluation of the Externship Experiences Arranged by Michigan State University Veterinary Medicine Students
Authors: Sprecher David J. , Krehbiel Janver D. , Hauptman Joe G. 
Published: January 2008

Rationale for the study – The clinical curriculum at the Michigan State University (MSU) College of Veterinary Medicine encourages off-campus study. One elective, veterinary externship, allows students to arrange experiences that are expected to challenge them academically and provide realism about private practice and nontraditional employment. This study was undertaken to describe the demographics of student-arranged externships and to characterize the evaluation of our students by on-site mentors. Methodology – Externship demographics and evaluation data were analyzed for the participants from two consecutive veterinary classes. Mentors evaluated 11 categories relating to student knowledge, ability, enthusiasm, or potential and responded to three questions. Results – 88% of students from the classes of 1999 and 2000 elected either one or two externships. Small animal practice settings predominated; externships were frequently used to gain experience with a particular species or discipline; and non–private practice settings accounted for 21% of the total. Statistical differences among the 11 evaluation categories are reported. Conclusions – Whether in traditional or nontraditional arenas, externships offer an effective way to give students choices in the attainment of veterinary skills, abilities, knowledge, and potential. Mentors were dedicated to their responsibilities and provided useful evaluations. In comparison to other evaluation categories, our students lacked an understanding of entry-level practice and business management concepts. Many mentors failed to equate practice and business management with the clinical education of veterinary students.
Adapting a Case-Based, Cooperative Learning Strategy to a Veterinary Parasitology Laboratory
Authors: Monahan Clifton M. , Yew Alice C. 
Published: January 2008

Introduction – Third-year veterinary students participate in a parasitology laboratory for instruction in diagnostic techniques. Course instructors adapted a case-based, cooperative learning approach to stimulate student involvement. Previously, students worked individually but shared common equipment in small groups. Peer interactions and discussions were not inherent in the format. Specimens were provided for practicing diagnostic techniques. Methodology – Students were assigned to cooperative learning groups of four students. Within each group, members were assigned distinct roles that rotated daily. Samples were presented as clinical cases, including history and signalment. Within groups, students performed role-specific duties and were expected to teach their component to other group members. Groups worked up their case for presentation to the class at the end of each period. Grading was unchanged from previous years, based on four individual quiz scores, two case reports, and a final practical exam. Results – Student grades remained satisfactory and student feedback was highly favorable, the most common response being that group work enhanced understanding and that a case-based approach provided valuable clinical insights. An important comment was that peer teaching could be inconsistent; some students were concerned that important information was overlooked during the reciprocal teaching. Their recommendation was to verbalize expectations more clearly and to work with groups to facilitate reciprocal teaching.
The Foot-and-Mouth Disease Epidemic of 2001 in the UK: Implications for the USA and the “War on Terror”
Authors: Gibbs Paul 
Published: January 2008

While there is no evidence to suggest that the recent epidemic of foot-and-mouth disease (FMD) in the UK and its subsequent spread to continental Europe were caused by bioterrorism, the extent of the epidemic shows that FMD could be a very powerful weapon for a bioterrorist wishing to cause widespread disease in livestock and economic disruption for the targeted country. This paper describes the epidemic. It then examines the contentious issues that arose through the use of extensive slaughter to control the epidemic and explores how, in turn, the concerns of society are being translated into a radical change in policy within the European Union with respect to the control of FMD and other foreign animal diseases. The crisis generated by the FMD epidemic in Europe in 2001 provides many lessons to be learned for the US and highlights the need for creative thinking in research and teaching within Colleges of Veterinary Medicine to more effectively address the threat of epidemic diseases under the “new world order.” There is general agreement that the veterinary profession in the US plays a unique role in protecting the nation against epidemic livestock diseases, whether caused naturally or through bioterrorism. The profession also has a significant role in protecting the publics health, since several epidemic diseases of animals, such as Rift Valley fever, are zoonotic. However, improved financial support at the federal and state levels is urgently needed to support epidemic- diseases research and teaching in Colleges of Veterinary Medicine.