bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance Paradigm Shift: Drilling Vertical and Directional Sections Through Abrasive Formations with Roller Cone Bits
Authors: Buske Robert , Rickabaugh Caleb , Bradford John , Lukasewich Heather , Overstreet Jim , Christensen Hughes
Published: June 2008

In several Canadian applications, operators have recognized the potential to replace standard roller cone products with a more viable solution that will drive down costs when drilling straight hole and curved sections. In these high-abrasive applications, roller cone bits are preferable because of their ability to increase ROP while maintaining a controlled direction and their relatively low price compared to polycrystalline diamond compact (PDC) bits. Typically, roller cone bits are removed from service because of damage or wear to the bearings or seals, and/or to the cutting structures. However, in these applications, the weakness occurs in the leg section.

Historically, wear protection on the leg outside diameter (OD) was achieved by placing tungsten carbide inserts in vulnerable locations. Although this increased wear resistance, the softer portion of the leg OD was still exposed to the damaging effects of hole-wall contact due to the required spacing between the tungsten carbide inserts. Also, the required drill holes for the inserts could become crack-propagation points in certain drilling environments.

To improve the durability of the leg while increasing seal and bearing reliability, abrasion-resistant hardfacing was incorporated onto the majority of the leg OD. Roller cone bits with the new hardfacing leg protection were field tested in several operators' wells with excellent results. The hardfacing leg protection proved to reduce OD wear more than TCI leg OD protection, therefore providing improved seal and bearing protection and thus reliability. Additionally, the hardfacing configuration stiffens the leg, increasing durability by reducing flexing and the potential of leg breakage. By preventing early bearing failure due to abrasive leg wear, this innovative technology has caused a performance paradigm shift and has significantly driven down drilling costs and non-productive time. The authors will present several case studies that document how the unique technology has increased the overall leg protection of roller cone products resulting in improved seal protection. This has led to an increase in total footage drilled in some applications and substantial cost savings to operators compared with standard roller cone products in those applications that do not have the new hardfacing.
Application of Stirling Cycle Generators in Production Operations
Authors: Dotson B. , Rochelle J. , Madden L.
Published: June 2008

Clean, inexpensive, and reliable on-site electric power generation for remote wellsites is an emerging need. There is a growing demand for electric power sources in the range of ½ to 1.5 kW to run pumping units and pumps on liquid loaded gas wells. To understand one possible option, a pilot project consisting of three 0.8 kW Stirling Cycle electric generators was conducted in Wyoming.

One generator was installed driving a conventional beam pump at the US Department of Energy's (DOE) Rocky Mountain Oilfield Testing Center (RMOTC). Two generators were installed for telemetry power service on well pads in the Wamsutter gas field. In addition to these two applications, small gas-fired generators could provide power for cathodic protection, chemical dosing systems, and other low rate pumping requirements.

The pilot demonstrated that a Stirling Cycle generator can pump a small well and provide SCADA power even in cold weather conditions. A simple fuel control and conditioning system provided reliable operation when properly installed. Operations and maintenance observations from the 1 year pilot will be presented.

Stirling Cycle engines are "external combustion engines" which offer some advantages over traditional "internal combustion engines": lower maintenance cost, low NOx emissions, and the recovery of heat for process uses. In fact, the current commercial equipment is best thought of as a ¾ kW cogeneration unit.
Practical Anisotropic Depth Migration
Authors: Schmid Ron , Stevenson Michael
Published: June 2008

In thrust belt areas along the margins of the continental Rocky Mountains and other environments with structural complexity, changes in subsurface lateral interval velocity requires depth migration of conventional surface seismic surveys to correctly position events. The presence of accompanying thick shale units overlying prospective drilling locations demand the depth migration procedure also compensate for anisotropic effects of wave propagation in a titled coordinate reference system. We start by briefly identifying the types of environments that are prospective candidates for depth migration. Then we observe the incremental improvements in subsurface imaging by following a continuum of conventional methods leading to anisotropic depth migration results. Seismic depths to well depths are compared. Finally, methods to derive the required anisotropic parameters are discussed.

As the technical understanding of anisotropic wave field propagation deepens and more examples are found in case histories the role of anisotropic depth migration will become more prominent. Increases in compute capabilities portend that this will become the new standard for structural seismic imaging.

This procedure significantly improves the imaging of faults, formations and reservoirs by correctly describing their lateral and vertical geometry. Thus it is a major risk mitigator. Moreover, it offers a means to invert seismic data into the depth domain to be used by the entire geoscience community.
Development of Coalbed Methane in Australia: Unique Approaches and Tools
Authors: Ham Y. , Kantzas A.
Published: June 2008

Coalbed Methane (CBM), also known as Coal Seam Gas (CSG) or Coal Seam Methane (CSM) in Australia is fast becoming a significant contributor to the country's energy needs. The potential coal seams for methane production in Australia are found in coal zones that are Jurassic to Permian in age with coal ranks ranging from sub-bituminous to low volatile bituminous coals. Many Australian coal seams contain high volumes of methane gas upto 25 m3 per tonne. Australia began producing CBM in 1988 but it was not until 1996 when the commercial CBM production started in the state of Queensland. Australia has total CBM reserves of about 300 to 500 Tcf (8.6 to 14.3 trillion m3).

With the total amount of CBM in-place reserves worldwide estimated to be between 3,500 and 95,000 Tcf (100 and 272 trillion m3), CBM is considered one of the world's largest sources of fossil fuel. In the United States, the total CBM in-place reserves are estimated at 749 Tcf (21.4 trillion m3), and CBM now represents almost 10% of its domestic natural gas production. Canada has just begun producing gas from CBM reservoirs and its estimated in-place CBM reserves are about 1,300 Tcf (37 trillion m3). In Australia, as CBM is seen as a clean and pipeline-quality energy, it is rapidly developing. Along with the large CBM resource, the main drivers for this move are the continuously reducing cost of coal seam gas production, and the depleting conventional energy resources.

A number of sophisticated CBM reservoir simulation and exploitation tools have been developed by the University of New South Wales and CSIRO to simulate the conventional CBM production as well as the CBM recovery using multi-component gases. In the field, Australia looks toward enhancing CBM recovery by injecting nitrogen and or carbon dioxide to increase CBM extraction. This paper will focus on how Australia is maximizing its CBM production.
Application of Flowing p/Z* Material Balance for Dry Coalbed-Methane Reservoirs
Authors: Morad K. , Clarkson C. R.
Published: June 2008

Material balance analysis is a fundamental technique for estimating gas-in-place. It can be achieved using: 1) Static material balance, using static (shut-in) reservoir pressures, where a plot of static p/z versus cumulative gas production is created to estimate original-gas-in-place (OGIP) or 2) Flowing material balance where gas rates and flowing pressures are used to estimate average reservoir pressure.

The flowing material balance concept of Agarwal-Gardner (1999) was extended to dry coalbed methane (CBM) reservoirs by Clarkson et al. (2007a) and Gerami et al. (2007) and to 2-phase (gas and water) CBM wells by Clarkson et al. (2007b). The present study further enhances the flowing material balance for dry CBM reservoirs by presenting a p/z* implementation of the concept.

This application, while accounting for the distinguishing characteristics of a CBM reservoir, uses the industry-standard practice of p/z material balance to calculate original-gas-in-place. As with the Agarwal-Gardner approach, the flowing p/z* method can be applied to variable gas rates and/or flowing pressures conditions.

In the present work, the derivation and iterative procedure of calculations are explained. Several test cases based on dry/immobile water saturation using real and synthetic data were generated. The resulting estimates of OGIP calculated from implementation of flowing p/z* material balance show excellent agreement and the estimated OGIP's are reliable.
Optimizing Gas Recovery With Solid Expandable Technology
Authors: Holland Mark , Chipiuk Jolene
Published: June 2008

Long touted as a "cleaner" energy source, natural gas provides an attractive fuel in a world market increasingly conscious of the environmental impact to recover and consume fossil fuels. As one of the world's largest producers of natural gas, Canada remains on the cutting edge of implementing new and innovative technology to extract natural gas efficiently, economically, and safely due in large part to potential reserves and the diverse environmental conditions that dictate such.

Efficiency starts with optimizing existing wells through remediation, revitalization, repair, or restoration. Solid expandable tubulars, specifically cased-hole liners, have proven to be a viable solution on all counts without compromising hole size or rendering completion equipment inadequate. Operators have used solid expandable solutions to facilitate a practical approach to gas field management and well operations. An operator in Texas used six liners in one well in preparation for six separate acid and fracture treatments. The installations placed five packer seats in the horizontal section and one expandable liner in the vertical section to support the damaged base casing. On the other end of the spectrum, an operator in Colorado used expandable technology to convert a depleted gas well into a water-disposal well that adhered to federal and state specifications. The operator covered 45-year-old perforations with two separate solid expandable tubular systems for safe water disposal from several wells in a prolific gas-producing field.

The application realm for this enabling technology continues to expand as operators pre-plan its use to optimize production. This paper will discuss how solid expandable tubulars, openhole liners or cased-hole liners, provide a cost-effective and technically-savvy approach to gas recovery. Comparing conditions and applications will illustrate how applicable these systems are suited for similar operations in Canada. Case histories will be used to demonstrate the robustness of expandable technology for diverse environments and objectives.
Central America Operator Uses Versatile Surface Packoff for Improved Well-Construction Operations
Authors: Monroy Rafael Rodriguez , Rogers Hank , Castro Jorge , Martinez Carlos
Published: June 2008

While using conventional surface launch cementing plugs during cementing operations performed on large diameter surface pipe, significant costs are incurred during the pumping of cement and displacement fluids because of the large volumes involved in the job. Additionally, high differential lifting pressures sometimes exceed the safe collapse load that can be applied to the large casing; thereby preventing the operator from checking the float valves after displacement is complete.

For several operational reasons, the operator elected to cement subsequently installed surface pipe using the inner-string method of displacement.

To help reduce overall job execution time and provide safer means of checking the floats after displacement is complete, a versatile surface packoff was incorporated into cementing operations on many large-diameter surface jobs. The time required to run the work string and install the surface packoff was easily justified with reduced costs associated with actual job execution. This paper documents the operators cost analysis along with operational benefits realized from the use of inner-string cementing and surface packoff methods.
New Environment-Friendly Cement Slurries With Enhanced Mechanical Properties
Authors: Mahmoudkhani Amir H. , Huynh Diana N. T. , Sylvestre Chuck , Schneider Jason
Published: June 2008

New cement slurries have been developed with significantly reduced greenhouse gas footprints when compared to conventional cement slurries used for oil and gas well cementing operations. The slurries consist of geopolymeric materials exhibiting superior chemical and mechanical properties at a competitive cost saving. A key attribute of the geopolymer technology is its robustness and versatility which enables products to have specific properties for slurries at densities as low as 1200 kg/m3. In these slurries, cement has been replaced by up to 60% of its weight with aluminosilicate materials. This includes lightweight slurries with high compressive and flexural strengths and desirable elasticity. The new slurry has been successfully placed as a lightweight lead cement in intermediate casing operations. The short- and long-term performances of the new blend will be presented in relation to each of its various well applications.
New Steel PDC Drill-Bit Technology Redefines Performance Standards in Key Natural-Gas Applications
Authors: Beaton Tim , Herman J. J. , Miko Chris , denOuden Bruce
Published: June 2008

One of the biggest ongoing challenges to the successful production of many natural gas reserves is the ability to improve drilling efficiency. In many of these applications, in order to drill the interval safely, it is necessary to drill through gas producing formations using high mud weight. As is well known in the industry, drilling with high mud weight poses significant challenges to drilling efficiency. Generally speaking, high mud weight equates to high solids content in the mud, and slow ROP for the drill bit, which means high hours to drill the section and frequent bit trips. Further to that, high hours and high solids equate to wear and erosion problems with bits and downhole equipment, leading to higher costs.

A new line of steel bodied drill bits has recently been introduced that has shown dramatic improvements in drilling efficiency in Western Canadian foothills natural gas applications. The hydraulic configuration (blade shape & height, void volume, junk slot area, nozzle orientation and TFA flexibility) of the drill bit is of paramount importance in applications with high mud weight. Bit balling is very common in these types of applications, and is very detrimental to drilling efficiency. The ability to utilize a steel body, and to protect it from the typical erosion and wear that is seen in high solid environments, is critical to maximizing hydraulic performance.

The new technology developed for these drill bits allows higher ROP in high mud weight applications, increased mechanical efficiency during the drilling process, and greatly enhanced wear / erosion resistance. Runs have been recorded in intervals with ≥ 1750 kg/m3 mud weight and > 85 cP viscosity showing dramatic increases in ROP, with absolutely no erosive wear to the body of the bit, even after drilling for ~ 160 hours. This significant increase in ROP is a major breakthrough as less time spent in the hole means less wear and erosion on all downhole components.
Screening of Oil-Degrading and Hydrogen-Producing Microorganisms for Microbial Conversion of CO2 into CH4 in Oil Reservoir
Authors: Sugai Y. , Niimi T. , Sasaki K. , Hattori Y. , Kano S. , Mukaidani T. , Fujiwara K. , Okatsu K.
Published: June 2008

CO2 sequestration into depleted oil reservoir has been expected as a method of reducing CO2 emission. Moreover, the authors focus on in-situ microbial conversion process of carbon dioxide into methane by hydrogenotrophic methanogens that inhabit oil reservoir universally. It is important for this process how to supply hydrogenotrophic methanogens with hydrogen for their methane production in reservoir. This study is aimed at searching for the oil-degrading and hydrogen-producing thermophilic bacteria (ODHPTB) which can produce hydrogen from oil in reservoir brine.

Reservoir brine was extracted from 10 producing wells in Yabase oilfield in Japan. Indigenous bacteria in brine samples were incubated with sterilized oil under anaerobic conditions (10% CO2 balance N2) at 50°C and/or 75°C. Both the production of hydrogen and methane and the consumption of carbon dioxide were observed in almost all culture solutions after 2 months incubation. The maximum rate of hydrogen production was 20.9 Nml/L-medium/day.

These culture solution and raw brine were inoculated into nutrient agar medium and incubated under anaerobic conditions at 50°C and 75°C. Microbial single colonies formed in the nutrient agar medium after 2 weeks incubation were picked and inoculated into sterilized brine including sterilized oil as a hydrogen source. More than 40 strains were isolated and incubated in the brine medium and 24 strains were observed to produce hydrogen from oil after 1 month incubation. The maximum rate of hydrogen production was 1.0 Nml/L-medium/day.

These results show that the in-situ microbial conversion process of carbon dioxide and residual oil into methane using ODHPTB and hydrogenotrophic methanogens is promising. Moreover, the most talented ODHPTB that was isolated in this study can be injected into reservoir in order to stimulate the conversion of carbon dioxide into methane.
Overseas Trained Teachers in England: A Policy Framework for Social and Professional Integration
Authors: Miller Paul Washington
Published: June 2008

Overseas trained teachers (OTTs) have become an important part of the makeup of England's primary and secondary education system. Through inadequate, and in some cases a lack of, initial induction and support for professional development, many are at risk of performing sub-optimally and some have become an endangered species. Failure to integrate OTTs in the norms, customs and nuances of the United Kingdom's (UK) system and teaching culture is tantamount to professional neglect and has, in certain cases, led to adjustment problems. With an ageing UK population and more skilled professionals moving abroad, the UK's dependency on OTTs is set to continue. After almost a decade of using the services of OTTs, the government remains non-committal in establishing a framework for effective integration. The expedient use of OTTs must give way to an inclusive and multifaceted integration approach involving governmental and non-governmental organisations and institutions, at all levels of society.
Tenure or Permanent Contracts in North American Higher Education? A Critical Assessment
Authors: Batterbury Simon
Published: June 2008

This article offers a critical perspective on the academic tenure system in the USA. Academic tenure is most frequently defended for the protection it affords freedom of speech in higher education, and it is attacked for its cost and lack of flexibility in a rapidly changing sector. The paper makes a third argument, that tenure sustains an unhealthy divide between tenured, untenured, and non-tenure-track staff members. It leads to differences in status, income, and job satisfaction that are inimical to basic principles of social justice. While financial considerations are a powerful factor in university efforts to constrain or challenge tenure, the maintenance of the tenure system and its use to control entry to permanent employment needs further examination. The author explores the system of ‘permanent’ contracts common in British and Australasian universities as an alternative for the USA – not because it benefits entrepreneurial university managers and administrators, but for its potential to offer a greater range of career positions for actual and potential staff members.
Envisioning the Classroom as a Social Movement Organization
Authors: Vanwynsberghe Rob , Moore Janet
Published: June 2008

This article describes the impact of an innovative higher education initiative called the Learning City Classroom, a project based on the presupposition that the classroom can raise awareness, foster solidarity and construct a collective identity consistent with being part of the sustainability movement. The Learning City Classroom is portrayed as an organizing, designing and implementation entity and as having all the qualities of an emerging social movement organization. The Learning City acts as a social movement organization by identifying shared objectives as critical to the sustainability movement. The outcome of this research shows not only that the university can support the sustainability social movement in concrete and tangible ways, but also, that it can do this in ways that are empowering for grassroots community groups as well as for students.
Hegel's Hold on Conceptions of Human Development
Authors: Mulryan Seamus
Published: June 2008

The use of development is ubiquitous in everyday language, and theories regarding it can be found in the social sciences and humanities. Although much work has been done to examine the meaning of development and its history, little attention has been paid to Hegel's role as the philosophical anchor for the modern life of development. By revisiting Hegel's Philosophy of History and analyzing some of the most influential thinkers in modern theories of human development – spanning economic, social, cognitive and moral – the author argues that these theories are far from escaping the Hegelian logic of Development. Furthermore, he warns of the potential violence necessarily assumed in such theories, and that revolutionizing the philosophical framework upon which developmental theories rest would be a worthwhile endeavor.
The TRIPS Agreement: Challenges and Possibilities in the Negotiation of Justice at the Transnational Level
Authors: Kalantzis-Cope Phillip
Published: June 2008

This article explores the relationship between the ideal of justice and institutional ‘structures’ administering justice/injustice within the contemporary international system through a study of the Trade Related Aspects of Property Right agreement specific focus is the question of ‘who counts’ in the negotiation of global justice, and the relationships between those affected by the global economic, political and social forces emanating from the agreement. The article problematises the territorial boundedness of questions of justice within a Westphalian horizon of political community. It also seeks to address the challenges that emerge through the example of the TRIPS agreement, and the possible trajectory of political community in a post-Westphalian world.
‘Emergency!’ Or How to Learn to Live with Neoliberal Globalization
Authors: Robbins Christopher G.
Published: June 2008

The author explores the cultural politics of neoliberal globalization, its deformations of critical facets of public culture as it has returned home, and he explores the politics of emergency. Rather than seeing the politics of emergency as something indicative of an emerging ‘emergency regime’ attendant to the terror war, he argues that the current politics of emergency is rooted in neoliberal globalization more generally, especially in terms of the need for powerbrokers to institutionalize insecurity and anxiety as central facets of a ‘new normal.’ He then turns to the criminalization and militarization of schools as examples of how the process of institutionalizing insecurity has unfolded in the last decade, suggesting that public schools are an ostensible and crucial site (being the one of the last sites to be precaritized) because the types of subjects and agents required for neoliberal globalization must learn how to live (in fear) with neoliberal globalization. Without an understanding of how schools are being leveraged to produce a ‘new normal,’ strategies for engaging schools as democratic public spheres will be potentially under-developed or mis-directed.
Results of diagnostic ophthalmic testing in healthy guinea pigs
Authors: Coster Martin E. , Stiles Jean , Krohne Sheryl G. , Raskin Rose E.
Published: June 2008

Objective—To report values for tear production, central corneal touch threshold (CTT), and intraocular pressure (IOP) in healthy guinea pigs and determine results of aerobic bacterial culture and cytologic examination of conjunctival swab specimens.

Design—Cross-sectional study.

Animals—31 healthy guinea pigs (62 eyes) of various ages and breeds.

Procedures—Tear production was measured by the phenol red thread tear test (PRT) and Schirmer tear test (STT) before and after topical anesthetic application, CTT was measured with an esthesiometer, and IOP was measured by applanation tonometry.

Results—Combining data from all eyes, mean ± SD PRT values before and after topical anesthetic administration were 21.26 ± 4.19 mm/15 s and 22.47 ± 3.31 mm/15 s, respectively, and mean IOP was 18.27 ± 4.55 mm Hg. Median STT values before and after topical anesthetic administration were 3 mm/min (range, 0 to 12 mm/min) and 4 mm/min (range, 0 to 11 mm/min), respectively, and median CTT was 2.0 cm (range, 0.5 to 3.0 cm). Values did not differ between eyes for any test, but significant differences were identified for PRT values between males and females and between values obtained before and after topical anesthetic administration. Common bacterial isolates included Corynebacterium spp, Streptococcus spp, and Staphylococcus spp. Cytologic examination of conjunctival swab specimens revealed mainly basal epithelial cells; lymphocytes were common.

Conclusions and Clinical Relevance—Results provided information on values for PRT, STT, CTT, and IOP in healthy guinea pigs and on expected findings for aerobic bacterial culture and cytologic examination of conjunctival swab specimens.
Effect of orally administered tramadol alone or with an intravenously administered opioid on minimum alveolar concentration of sevoflurane in cats
Authors: Ko Jeff C. H. , Abbo Lisa A. , Weil Ann B. , Johnson Brenda M. , Inoue Tomohito , Payton Mark E.
Published: June 2008

Objective—To compare the effect of oral administration of tramadol alone and with IV administration of butorphanol or hydromorphone on the minimum alveolar concentration (MAC) of sevoflurane in cats.

Design—Crossover study.

Animals—8 healthy 3-year-old cats.

Procedures—Cats were anesthetized with sevoflurane in 100% oxygen. A standard tail clamp method was used to determine the MAC of sevoflurane following administration of tramadol (8.6 to 11.6 mg/kg [3.6 to 5.3 mg/lb], PO, 5 minutes before induction of anesthesia), butorphanol (0.4 mg/kg [0.18 mg/lb], IV, 30 minutes after induction), hydromorphone (0.1 mg/kg [0.04 mg/lb], IV, 30 minutes after induction), saline (0.9% NaCl) solution (0.05 mL/kg [0.023 mL/lb], IV, 30 minutes after induction), or tramadol with butorphanol or with hydromorphone (same doses and routes of administration). Naloxone (0.02 mg/kg [0.009 mg/lb], IV) was used to reverse the effects of treatments, and MACs were redetermined.

Results—Mean ± SEM MACs for sevoflurane after administration of tramadol (1.48 ± 0.20%), butorphanol (1.20 ± 0.16%), hydromorphone (1.76 ± 0.15%), tramadol and butorphanol (1.48 ± 0.20%), and tramadol and hydromorphone (1.85 ± 0.20%) were significantly less than those after administration of saline solution (2.45 ± 0.22%). Naloxone reversed the reductions in MACs.

Conclusions and Clinical Relevance—Administration of tramadol, butorphanol, or hydromorphone reduced the MAC of sevoflurane in cats, compared with that in cats treated with saline solution. The reductions detected were likely mediated by effects of the drugs on opioid receptors. An additional reduction in MAC was not detected when tramadol was administered with butorphanol or hydromorphone.
Use of propofol for anesthesia in cats with primary hepatic lipidosis: 44 cases (1995–2004)
Authors: Posner Lysa P. , Asakawa Makoto , Erb Hollis N.
Published: June 2008

Objective—To determine morbidity and fatalities in cats with hepatic lipidosis that received propofol to facilitate placement of a feeding tube.

Study Design—Retrospective case series.

Animals—44 cats with presumed primary hepatic lipidosis anesthetized for placement of a feeding tube.

Procedures—Medical records from January 1995 through December 2004 were reviewed to identify cats that matched the inclusion criteria (histologic confirmation of hepatic lipidosis, anesthetized for placement of feeding tube, complete intensive care unit [ICU] records, and recorded outcome). Data extracted included age, body weight, sex, anesthetic drugs, drug dosages, type of feeding tube, duration of anesthesia, number of hours in ICU, administration of blood products, and survival until discharge from ICU.

Results—44 cats (21 females and 23 males) were included in the analysis. Age range was 3 to 15 years (median, 8 years), and body weight ranged from 1.8 to 9.0 kg (4.0 to 19.8 lb), with a median of 4.8 kg (10.6 lb). Twenty-seven cats were administered propofol. There was no significant association between the use of propofol or the dosage of propofol and any risk factor, need for blood products, number of hours in the ICU, or survival. There was no significant difference between cats that received propofol and cats that did not receive propofol with regard to interval until discharge from the ICU.

Conclusions and Clinical Relevance—The use of propofol did not increase morbidity or fatalities in cats with primary hepatic lipidosis. Thus, propofol can be used in these cats for placement of a feeding tube.
Association of magnetic resonance imaging findings and histologic diagnosis in dogs with nasal disease: 78 cases (2001—2004)
Authors: Miles Macon S. , Dhaliwal Ravinder S. , Moore Michael P. , Reed Ann L.
Published: June 2008

Objective—To determine whether magnetic resonance imaging (MRI) features correlated with histologic diagnosis in dogs with nasal disease.

Design—Retrospective case series.

Animals—78 dogs undergoing MRI for evaluation of nasal disease.

Procedures—Medical records and MRI reports of dogs were reviewed to identify MRI features associated with histologic diagnosis. Features evaluated were presence of a mass effect, frontal sinus involvement, sphenoid sinus involvement, maxillary recess involvement, nasopharyngeal infiltration by soft tissue, nasal turbinate destruction, vomer bone lysis, paranasal bone destruction, cribriform plate erosion, and lesion extent (ie, unilateral vs bilateral).

Results—33 dogs had neoplastic disease, 38 had inflammatory rhinitis, and 7 had fungal rhinitis. Lesion extent was not significantly associated with histologic diagnosis. Absence of a mass effect was significantly associated with inflammatory disease. However, presence of a mass was not specific for neoplasia. In dogs with evidence of a mass on magnetic resonance (MR) images, nasal turbinate destruction, frontal sinus invasion, and maxillary recess invasion were not useful in distinguishing neoplastic from nonneoplastic disease, but cribriform plate erosion, vomer bone lysis, paranasal bone destruction, sphenoid sinus invasion, and nasopharyngeal invasion were.

Conclusions and Clinical Relevance—Results suggested that in dogs with nasal disease, the lack of a mass effect on MR images was significantly associated with inflammatory disease. In dogs with a mass effect on MR images, vomer bone lysis, cribriform plate erosion, paranasal bone destruction, sphenoid sinus invasion by a mass, and nasopharyngeal invasion by a mass were significantly associated with a diagnosis of neoplasia.
Percutaneous endovascular retrieval of an intravascular foreign body in five dogs, a goat, and a horse
Authors: Culp William T. N. , Weisse Chick , Berent Allyson C. , Getman Liberty M. , Schaer Thomas P. , Solomon Jeffrey A.
Published: June 2008

Case Description—5 dogs, 1 goat, and 1 horse underwent percutaneous endovascular retrieval of intravascular foreign bodies between 2002 and 2007.

Clinical Findings—Foreign bodies were IV catheters in 4 dogs, the horse, and the goat and a piece of a balloon valvuloplasty catheter in 1 dog. Location of the foreign bodies included the main pulmonary artery (1 dog), a branch of a pulmonary artery (4 dogs), the right ventricle (the goat), and a jugular vein (the horse).

Treatment and Outcome—The procedure of percutaneous endovascular retrieval of the foreign body was easy to perform in all instances. One dog was euthanized 41 days after retrieval because of worsening of another disease process, and 1 dog had abnormal neurologic signs secondary to a brain mass. All other animals were clinically normal during the follow-up period (follow-up duration, 3 to 57 months). None of the animals developed long-term complications secondary to the foreign body retrieval procedure.

Clinical Relevance—Intravascular foreign bodies that result from catheters or devices used during minimally invasive techniques are rare but may cause substantial morbidity. Percutaneous endovascular retrieval of intravascular foreign bodies was easily and safely performed in the 7 animals reported here. Use of percutaneous endovascular retrieval techniques should be considered for treatment of animals with intravascular foreign bodies because morbidity can be substantially decreased; however, proper selection of patients for the procedure is necessary.
Laparoscopic-assisted implantation of a urinary catheter in male sheep
Authors: Franz Sonja , Dadak Agnes M. , Schöffmann Gudrun , Coppens Paul , Khol Johannes L. , Baumgartner Walter , Dupre Gilles
Published: June 2008

Objective—To evaluate a laparoscopic technique for implantation of a urinary catheter in the right paramedian area in male sheep and to determine feasibility, benefits, and risks for this technique.

Design—Evaluation study.

Animals—6 healthy male sheep (mean ± SD body weight, 42.16 ± 11.95 kg [92.75 ± 26.29 lb]).

Procedures—Each sheep was anesthetized and positioned in dorsal recumbency. A 10-mm laparoscope was inserted in the right paramedian area between the xiphoid and preputial orifice. After creation of capnoperitoneum, grasping forceps were inserted in the left paramedian area at the level of the teats and used to immobilize the urinary bladder. A pigtail balloon catheter was implanted transcutaneously in the right paramedian area between the preputial orifice and teats and directed into the urinary bladder by use of laparoscopic guidance. The catheter was removed 10 days after implantation. Fourteen days after initial surgery, a second laparoscopy was performed to evaluate pathologic changes.

Results—Inadvertent insertion of the first trocar into the rumen of 1 sheep was the only intraoperative complication encountered. Laparoscopic-assisted implantation of the urinary catheter was successfully performed in all sheep. No postoperative complications were detected.

Conclusions and Clinical Relevance—Laparoscopic-assisted implantation of a urinary catheter in the right paramedian area was successfully performed and may be a feasible method for use in sheep. This method can be considered as an alternative to tube cystotomy performed by laparotomy.
Infection control practices and zoonotic disease risks among veterinarians in the United States
Authors: Wright Jennifer G. , Jung Sherry , Holman Robert C. , Marano Nina N. , McQuiston Jennifer H.
Published: June 2008

Objective—To assess the knowledge and use of infection control practices (ICPs) among US veterinarians.

Design—Anonymous mail-out population survey.

Procedures—In 2005 a questionnaire was mailed to US small animal, large animal, and equine veterinarians who were randomly selected from the AVMA membership to assess precaution awareness (PA) and veterinarians' perceptions of zoonotic disease risks. Respondents were assigned a PA score (0 to 4) on the basis of their responses (higher scores representing higher stringency of ICPs); within a practice type, respondents' scores were categorized as being within the upper 25% or lower 75% of scores (high and low PA ranking, respectively). Characteristics associated with low PA rankings were assessed.

Results—Generally, respondents did not engage in protective behaviors or use personal protective equipment considered appropriate to protect against zoonotic disease transmission. Small animal and equine veterinarians employed in practices that had no written infection control policy were significantly more likely to have low PA ranking. Male gender was associated with low PA ranking among small animal and large animal veterinarians; equine practitioners not working in a teaching or referral hospital were more likely to have low PA ranking than equine practitioners working in such institutions.

Conclusions and Clinical Relevance—Results indicated that most US veterinarians are not aware of appropriate personal protective equipment use and do not engage in practices that may help reduce zoonotic disease transmission. Gender differences may influence personal choices for ICPs. Provision of information and training on ICPs and establishment of written infection control policies could be effective means of improving ICPs in veterinary practices.
Frequency of holoprosencephaly in the International Clearinghouse Birth Defects Surveillance Systems: Searching for population variations
Authors: Leoncini Emanuele , Baranello Giovanni , Orioli Iêda M. , Annerén Göran , Bakker Marian , Bianchi Fabrizio , Bower Carol , Canfield Mark A. , Castilla Eduardo E. , Cocchi Guido , Correa Adolfo , De Vigan Catherine , Doray Berenice , Feldkamp Marcia L. , Gatt Miriam , Irgens Lorentz M. , Lowry R. Brian , Maraschini Alice , Mc Donnell Robert , Morgan Margery , Mutchinick Osvaldo , Poetzsch Simone , Riley Merilyn , Ritvanen Annukka , Gnansia Elisabeth Robert , Scarano Gioacchino , Sipek Antonin , Tenconi Romano , Mastroiacovo Pierpaolo
Published: June 2008

BACKGROUND: Holoprosencephaly (HPE) is a developmental field defect of the brain that results in incomplete separation of the cerebral hemispheres that includes less severe phenotypes, such as arhinencephaly and single median maxillary central incisor. Information on the epidemiology of HPE is limited, both because few population‐based studies have been reported, and because small studies must observe a greater number of years in order to accumulate sufficient numbers of births for a reliable estimate. METHODS: We collected data from 2000 through 2004 from 24 of the 46 Birth Defects Registry Members of the International Clearinghouse for Birth Defects Surveillance and Research. This study is based on more than 7 million births in various areas from North and South America, Europe, and Australia. RESULTS: A total of 963 HPE cases were registered, yielding an overall prevalence of 1.31 per 10,000 births. Because the estimate was heterogeneous, possible causes of variations among populations were analyzed: random variation, under‐reporting and over‐reporting bias, variation in proportion of termination of pregnancies among all registered cases and real differences among populations. CONCLUSIONS: The data do not suggest large differences in total prevalence of HPE among the studied populations that would be useful to generate etiological hypotheses. Birth Defects Research (Part A), 2008. © 2008 Wiley‐Liss, Inc.
Behavior analyst use of and beliefs in treatments for people with autism
Authors: Schreck Kimberly A. , Mazur Alison
Published: June 2008

With the increase in the numbers of children diagnosed with autism and scientific support solely for Applied Behavior Analysis (ABA) treatment, a proliferation of professionals have sought ABA training to provide services to this population. However, not all have been reportedly providing solely ABA services. This study surveyed Board Certified Behavior Analysts (BCBAs; N = 469) concerning their beliefs, endorsement, and use of a variety of scientifically supported and unsupported treatments for people with autism. Although not all endorsed using ABA, BCBA professionals most widely reported using ABA and ABA‐related treatments. Surprisingly, BCBAs endorsed and used all types of treatments, despite their beliefs that the treatments were difficult to implement, not cost effective, and not supported by research. Copyright © 2008 John Wiley & Sons, Ltd.
Recent advances in three‐dimensional multicellular spheroid culture for biomedical research
Authors: Lin Ruei‐Zhen , Chang Hwan‐You
Published: June 2008

Many types of mammalian cells can aggregate and differentiate into 3‐D multicellular spheroids when cultured in suspension or a nonadhesive environment. Compared to conventional monolayer cultures, multicellular spheroids resemble real tissues better in terms of structural and functional properties. Multicellular spheroids formed by transformed cells are widely used as avascular tumor models for metastasis and invasion research and for therapeutic screening. Many primary or progenitor cells on the other hand, show significantly enhanced viability and functional performance when grown as spheroids. Multicellular spheroids in this aspect are ideal building units for tissue reconstruction. Here we review the current understanding of multicellular spheroid formation mechanisms, their biomedical applications, and recent advances in spheroid culture, manipulation, and analysis techniques.
Atomic Vapor Deposition of Titanium Nitride as Metal Electrodes for Gate‐last CMOS and MIM Devices
Authors: Lukosius Mindaugas , Wenger Christian , Pasko Sergej , Müssig Hans‐Joachim , Seitzinger Bernhard , Lohe Christoph
Published: June 2008

Pure and diluted Ti[N(Et)2]4 precursors are used to grow TiN layers at 400–600 °C by using atomic vapor deposition (AVD®). The composition, microstructure, and electrical properties of TiN films with various thicknesses are investigated. The determined work function of 4.7 eV indicates the possibility of using AVD®‐grown TiN as a metal gate electrode for PMOSFET and metal‐insulator‐metal (MIM) devices. TiN/HfO2/SiO2 stacks are integrated into gate‐last PMOS transistors, and the extracted parameters are compared to poly‐Si/SiO2 reference transistors. The optimized films grown at 400 °C with a thickness of 20 nm exhibit a resistivity of 400 µΩ cm.
Intramolecular Cyclization of N‐Arylphosphinimidic Isocyanates – Novel Approach to a 4a,8a‐Dihydro‐1,3,2λ5‐benzodiazaphosphinin‐4(3H)‐one System
Authors: Marchenko Anatoliy P. , Koydan Georgiy K. , Smaliy Radomyr V. , Chaykovskaya Aleksandra A. , Pinchuk Aleksandr M. , Tolmachev Andrey A. , Shishkin Oleg V.
Published: June 2008

A previously unknown type of 1,3,2λ5‐benzodiazaphosphinin‐4(3H)‐ones was obtained by intramolecular heterocyclization of novel N‐arylphosphinimidic isocyanates. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Computation of time delay margin for power system small‐signal stability
Authors: Ayasun Saffet
Published: June 2008

With the extensive use of phasor measurement units (PMU) in the wide‐area measurement/monitoring systems (WAMS), time delays have become unavoidable in power systems. This paper presents a direct and exact method to compute the delay margin of power systems with single and commensurate time delays. The delay margin is the maximum amount of time delay that the system can tolerate before it becomes unstable for a given operating point. First, without using any approximation or substitution, the transcendental characteristic equation is converted into a polynomial without the transcendentality such that its real roots coincide with the imaginary roots of the characteristic equation exactly. The resulting polynomial also enables us to easily determine the delay dependency of the system stability and the sensitivities of crossing roots with respect to time delay. Then, an expression in terms of system parameters and imaginary root of the characteristic equation is derived for computing the delay margin. The proposed method is applied to a single‐machine‐infinite bus (SMIB) power system with an exciter. Delay margins are computed for a wide range of system parameters including generator mechanical power, damping and transient reactance, exciter gain, and transmission line reactance. The results indicate that the delay margin decreases as the mechanical power, exciter gain and line reactance increase while it increases with increasing generator transient reactance Additionally, the relationship between the delay margin and generator damping is found be relatively complex. Finally, the theoretical delay margin results are validated using the time‐domain simulations of Matlab. Copyright © 2008 John Wiley & Sons, Ltd.
Is there information contained within the sentence‐writing component of the mini mental state examination? A retrospective study of community dwelling older people
Authors: Shenkin Susan D. , Starr John M. , Dunn Joanne M. , Carter Samantha , Deary Ian J.
Published: June 2008

Objective

To investigate the relationship between features of the MMSE written sentence and cognitive function, depression and disability.

Methods

MMSE sentences from 191 community dwelling individuals without dementia from the Lothian Birth Cohort 1921 (LBC1921) study were: (a) photocopied and (b) typed as written. Sentences were rated for objective criteria: word number and frequency, first person usage, time orientation, and letter case. Twenty healthy raters (50% male, age 20–26 years), blind to all other data, rated each handwritten and typed sentence for subjective criteria: legibility, ‘emotional’ tone (positive to negative), estimated age, health, and intelligence. As part of the LBC1921 volunteers had results available for cognitive ability tests (from which we extracted a general cognitive ability factor, g), Hospital Anxiety and Depression Score (HADS), and Townsend disability scores.

Results

43.5% of subjects were male, mean age 78.6, SD 0.43 years. There was no significant association between the objective sentence criteria, legibility or tone and measured cognitive ability or physical disability. However, estimates of intelligence from the MMSE written sentence correlated significantly with current cognitive ability (r = 0.29, p < 0.001). There was a trend towards sentences with a negative tone being associated with a higher HADS‐depression score (rho = −0.12, p = 0.09).

Conclusion

In community dwelling people aged around 80 years, despite no association between objectively rated features of the MMSE sentence and intelligence or disability, raters were able to make better‐than‐chance estimates of subjects' intelligence test scores. Copyright © 2008 John Wiley & Sons, Ltd.