Journal of Toxicology and Environmental Health Sciences, Mar 31, 2011
The Buffalo Lupus Project was a community-based participatory research partnership formed to addr... more The Buffalo Lupus Project was a community-based participatory research partnership formed to address the relationship between an identified hazardous waste site and high rates of lupus and other autoimmune diseases in the surrounding community. Most cases identified began experiencing symptoms and were diagnosed in the periods when the site was inactive. Trends suggest that the impact of the site was more likely due to chronic exposure to waste rather than it being an acute trigger.
A geographic information assessment of exposure to a toxic waste site and development of systemic... more A geographic information assessment of exposure to a toxic waste site and development of systemic lupus erythematosus (SLE): Findings from the buffalo lupus project
International Journal of Sports Science and Coaching, 2008
A sample of 25 golfers, 12 professionals and 13 amateurs, ages 23 to 63 years, were measured for ... more A sample of 25 golfers, 12 professionals and 13 amateurs, ages 23 to 63 years, were measured for transverse plane pelvic rotation using light electrodes positioned bilaterally on the iliac crests. Transverse plane pelvic rotation was present in all of the golfers measured. All subjects were measured from a shoulder width stance, two inches wider and two inches narrower than shoulder width in a standing, erect posture and a golf setup posture without a club. Transverse plane pelvic rotation in the 25 subjects ranged from 1 inch to 4 inches as recorded by stance correction with an average of 2.25 inches of rotation at a shoulder width stance. A dowel pole bar with light electrodes fixed to the bar was attached to the transverse pelvic plane 3 inches below the iliac crest for the purpose of validation of a measurement instrument in the field. The pelvic rotation was temporarily corrected through a simple three minute exercise program. Nineteen of the 25 subjects were seen in follow-up in the field where the dowel bar was used and they had each returned to their measured baseline pelvic rotation. Again, their measured pelvic rotation was corrected via a simple three minute exercise program. The authors discuss the use of the exercise program for both golf coaching and research, and also present the validation of a simple instrument that could be used in the field to measure transverse pelvic plane rotation.
To describe the participatory approach used to develop ''Good For The Neighborhood'' (GFTN), a co... more To describe the participatory approach used to develop ''Good For The Neighborhood'' (GFTN), a community program to improve the health of four underserved communities. A core program was developed involving a ''park and stay'' approach to impact four underserved predominately minority communities (two predominately African American, 1 predominately Latino, and the Seneca Nation of Indians). The core program includes health screenings, risk assessments, health education, and exposure to health services. An extensive tracking and evaluation system was developed to determine participation and impact on the community. Multi-methods (key informant interviews, focus groups, surveys) were implemented to gain feedback from community partners and participants as to how to adopt the program to meet the needs of the community. GFTN has been sustained for over 3 years and has reached over 3,500 predominately minority individuals in four communities with 1/3 of participants engaging regularly in the program. The program has evolved in the four communities to meet specific needs. A ''park and stay'' approach in partnership with the community has led to a strong program that community partners and residents embrace. Community ownership and social networking, including word-of-mouth from residents is essential to establishing a successful program.
This study determines the impact of provider knowledge and attitude on implementation of guidelin... more This study determines the impact of provider knowledge and attitude on implementation of guidelines: spirometry, peak flows, patient assessments, action plans, severity assessment, and anti-inflammatories. A self-administered survey conducted in academic family practice sites in Buffalo, NY assessed knowledge, self-reported use, and perceived usefulness. Knowledge was associated with regular use of peak flows (p = 0.048) and anti-inflammatories (p = 0.01). Positive attitude was associated with regular use of spirometry (p = 0.03), peak flows (p < or = 0.001), patient assessments (p = 0.02), action plans (p = 0.046), anti-inflammatories (p < or = 0.001), and severity assessment (p < or = 0.001). Perceived usefulness is critical to implementing asthma guidelines. Interventions to improve provider adherence must address attitude.
This study presents an uncontrolled preliminary evaluation of a pilot health insurance subsidy pr... more This study presents an uncontrolled preliminary evaluation of a pilot health insurance subsidy program and addresses whether provision of subsidized insurance that required employee contribution had an impact upon preventive health utilization among small businesses and their employees. Self-report questionnaires were mailed to the employees; these included questions on use of preventive health services before and after enrollment in the subsidy program. The analysis was stratified by self-reported prior enrollment in an insurance program to compare employees with and without prior health insurance. The findings suggest significant increases in health service utilization among the previously uninsured. Regular checkups more than doubled (p < .0001), as did the number of individuals receiving regular blood work (p < .0001). Nearly twice the number of individuals filled regular prescriptions after enrollment in the subsidy program as compared with before (p…
Community-based participatory research (CBPR) is a mechanism to improve environmental quality in ... more Community-based participatory research (CBPR) is a mechanism to improve environmental quality in communities primarily inhabited by minorities or low income families. A collaborative partnership between the University at Buffalo and the Toxic Waste Lupus Coalition was formed to investigate the high prevalence of lupus in the area and whether cases of disease were linked to chemicals found at a nearby New York State Superfund site in East Buffalo. The purpose of the study was to use CBPR practices to educate impacted residents and enable their participation in efforts to get a nearby contaminated waste site remediated. Community members were active participants in the development of the plan to clean up the toxic site. These methods can be used to better engage the community in research and involve them in actions taken to improve their neighborhood.
Complications of anterior lumbar fusion may be divided into several categories. The first of thes... more Complications of anterior lumbar fusion may be divided into several categories. The first of these is complications related to patient selection, the second is visceral complications, and the third is vascular complications. Complications of anterior lumbar fusion and complications of interbody fusion technique occur at the graft site and the donor site. Patient selection is very i m p~r t a n t .~ The patient's preoperative findings must indicate that the benefit of anterior surgery outweighs the potential complications. The proper approach for each individual patient must be planned. The standard leftsided oblique or transverse skin incision for L5-S1 should point toward the midline at the junction of the distal and middle third of the distance between the umbilicus and the pubis; for L4-L5, it should be the junction of the proximal and middle third. The danger is usually not being low enough. Dissection from caudal to cephalad is usually easier than cephalad to caudal, especially when there is a significant amount of lumbar lordosis and the disk space is angled caudally anteriorly. This makes visualization of the posterior aspect of the disk space difficult. For cases with extreme lumbar lordosis, one way of avoiding this inability to visualize the disk space is to use a vertical midline or pararectus From the Kerlan-Jobe Orthopaedic Clinic, Las An-Reprint requests to
Sequential rhetoric can serve as a framework to instruct UX practice (through user story maps) to... more Sequential rhetoric can serve as a framework to instruct UX practice (through user story maps) to new learners because it is both approachable and affordable. Sequential rhetoric consists of five main facets that incorporate planning elements (core visual writing and envisaging) and composing elements (interanimation, juxtaquencing, and gestalt closure), which this essay both defines and relates to convergent scholarship. We argue that sequential rhetoric transfers beyond the technical classroom and into the profession itself.
Proceedings of SPE Annual Fall Technical Conference and Exhibition, 1978
Past research in miscible flooding has indicated some residual oil may be left in carbon dioxide ... more Past research in miscible flooding has indicated some residual oil may be left in carbon dioxide swept rock as a result of CO2-oil phase behavior, rock pore structure, or mobile water saturation. Determination of the magnitude of this residual oil saturation in the reservoir rock of interest is important when a field is evaluated for CO2 miscible flooding. However, miscible displacements in laboratory outcrop cores sometimes exhibit a length effect, suggesting that reservoir rock samples as long as ten feet or greater may be required for the determination of the true unit displacement efficiency. This paper describes the development of a technique allowing the measurement of CO2 unit displacement efficiency in short core system consisting of either actual reservoir rock or outcrop sandstones. A number of core floods were performed under varying conditions in which continuously injected CO2 displaced a synthesized reservoir fluid from 15- to 30-cm long Berea sandstone cores and low permeability carbonate cores from a West Texas permeability carbonate cores from a West Texas reservoir. For secondary and tertiary recovery floods in both core types, residual oil saturations comparable to those reported for long sandstone systems were observed when solvent fingering was controlled. Length and rate effects previously observed are demonstrated to depend primarily on solvent sweep efficiency rather than the mechanism for achieving miscibility. The current as well as previous studies show that gravity, transverse dispersion, and viscosity gradation may each be effective stabilizing mechanisms under appropriate conditions. This work allows the relative importance of each to be estimated in a core flood and for the first time their combined influence correlated with the measured overall displacement efficiency. Two methods are described and shown to be effective for generating the viscosity graded CO2-oil transition zone required for flood stabilization when gravity and transverse dispersion are relatively unimportant, as in short, low permeability reservoir core samples. Based on these concepts, laboratory CO2 floods may be designed to prevent viscous fingering now enabling measurement of the true CO2 unit displacement efficiency in short laboratory systems. Introduction Carbon dioxide miscible flooding is one of the more promising processes for enhanced oil recovery. Evaluation of prospects for full-scale CO2 flooding requires a thorough understanding of recovery behavior. Unit displacement efficiency is an important factor in such an evaluation and, because unit displacement efficiency may depend on rock and fluid properties, core displacement tests in actual properties, core displacement tests in actual reservoir rock using realistic reservoir fluids may be necessary for the evaluation of each candidate reservoir. This paper describes a technique for flooding short pieces of reservoir rock containing reservoir fluids at reservoir temperature to determine the residual oil saturation left in the fully-swept rock. Very few CO2 miscible displacement tests have been performed in the past using actual reservoir rock. Instead, most laboratory studies of CO2 flooding (as well as with LPG and other solvents) have been conducted using outcrop sandstone cores. Berea, Boise and Torpedo sandstones were chosen due to their availability and uniformity. These sandstones can be cut easily into lengths of approximately 10 ft, and much longer systems for displacement studies can be constructed by butting cores together. Reservoir rock, on the other hand, must be obtained from oil-field core samples. Lengths of reservoir rock for laboratory flooding are limited to several feet at most for stacked cores and to considerably less for single cores. A wide variation in the apparent residual oil saturation left to miscible flooding, Sor, has been observed in laboratory displacements with both CO2 above the multi-contact miscibility pressure and with first-contact miscible fluids even when similar porous media were used. porous media were used.
Community-based participatory research requires the participation of community stakeholders to in... more Community-based participatory research requires the participation of community stakeholders to inform the process. The West Side Community Asthma Project, a community-based participatory research program to study the effects of the environment on asthma conducted in Buffalo, N. Y., identified a stakeholders group of community leaders and activists. Creative strategies have been implemented to reach out to other community residents to invite them to participate in the participatory process. Community-based participatory research has been defined as "a collaborative approach to research that equitably involves all partners in the research process and recognizes the unique strengths that each brings. Community-based participatory research begins with a research topic of importance to the community and has the aim of combining knowledge with action and achieving social change to improve health outcomes and eliminate health disparities."(Community Health Scholars Program, 2004)
BACKGROUND CONTEXT: Andriacchi performed a computer-simulated mathematical analysis showing that ... more BACKGROUND CONTEXT: Andriacchi performed a computer-simulated mathematical analysis showing that the rib cage enhances stability of the normal thoracic spine in flexion, rotation, lateral bending, and especially extension. He showed an increase of 27 per cent in flexion and of 132 percent in extension with the addition of the rib cage. Panjabi and White established criteria assessing stability in the thoracic spine by performing studies supporting the stabilizing role of the costovertebral joints. However, these experiments underestimated the role of the rib cage because the ribs were removed 3 cm lateral to the costovertebral joints. Recently, Oda et al. showed significant increases in the neutral zone in lateral bending and axial rotation after resection of the costovertebral joints and destruction of the rib cage. The limitation to this study was the use of canine specimens rather than human. There is no published study of biomechanical testing of human cadaveric specimens with the rib cage intact. PURPOSE: To determine the amount of stability the rib cage imparts to the thoracic spine and to show the amount of stability lost by a sternal fracture. STUDY DESIGN/SETTING: Specimens were tested using a biaxial material testing machine (MTS) synchronized with an opto-electronic three-dimensional motion measuring device (Opto-trak 3020). PATIENT SAMPLE: Ten fresh-frozen human cadaveric thoracic spines with the rib cage and sternum intact. OUTCOME MEASURES: Multidirectional flexibility of the whole thoracic spine was measured using the Optotrak 3020, an opto-electronic threedimensional motion measuring device. This machine uses three cameras to detect movement of multiplexed arrays of light emiting diodes (LEDs). An array attached to the MTS machine established the fixed coordinate axes. One array was attached to T1 by way of a rigid pin placed in the pedicle. With T12 rigidly fixed to the base of the MTS system, motion of the T1 array represented motion of the entire thoracic spine specimen. METHODS: The specimens were tested in axial compression, axial rotation, lateral bending, and flexion/extension. First, the specimens were tested through all four loading types with the sternum and rib cage intact. Next, the sternum was fractured at the sternomanubrial junction displacing the proximal fragment posteriorly. Lastly, the entire rib cage was removed by cutting the ribs 3 cm lateral to the costovertebral joints. RESULTS: The rib cage increased the stability of the thoracic spine by 40% in flexion/extension (pϭ.012), 35% in lateral bending (pϭ.038), and 31% in axial rotation (pϭ.008). An indirect flexion-compression type of sternal fracture decreased the stability of the thoracic spine by 42% in flexion/extension (pϭ.036), 22% in lateral bending (pϭ.008), and 15% in axial rotation (pϭ.011). CONCLUSIONS: The rib cage significantly increases the stability of the thoracic spine in flexion/extension, lateral bending, and axial rotation. A sternal fracture significantly decreases the stability of the thorax. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: Author (RWI) Other: Synthes, Sofamor-Danek, Depuy, and Blackstone all contributed monetary funds to pay for the materials of this project.
Retrospective radiographic analysis.To determine the fusion rate of stand-alone lateral lumbar in... more Retrospective radiographic analysis.To determine the fusion rate of stand-alone lateral lumbar interbody fusion (LLIF).Biomechanical studies have indicated that LLIF may be more stable than anterior or transforaminal lumbar interbody fusion. Early clinical reports of stand-alone LLIF have shown success in obtaining fusion and indirectly decompressing nerve roots.A consecutive case series of stand-alone LLIF was analyzed with chart and radiographic review. Non-union was determined by symptomatology consistent with non-union and absence of bridging bone on the CT scan.Thirty-nine levels of stand alone LLIF were performed in 23 patients. Eleven patients received 1-level surgery, 7 patients received 2-level surgery, 3 patients received 3-level surgery, and 1 patient received 4-level surgery. Excluding 1 infected case, we analyzed 37 levels of stand alone LLIF in 22 patients. Non-union incidence was 7 levels in 6 patients. Non-union rate was 7/37 (19%) per level and 6/22 (27%) per patien...
retrolisthesis of L4 vertebra were analyzed with the Student t test. The confidence level for sig... more retrolisthesis of L4 vertebra were analyzed with the Student t test. The confidence level for significance was pOT0.05. RESULTS: The mean cross-sectional area of the L4-5 intervertebral foramen of the anatomic spine was 171.70636.38 mm 2 at the left side and 170.68637.28 mm 2 at the right side. No significant difference was found between the left and right sides (pO.05). No significant difference was found between the measured values using Aquarius Image software of the CT scanner and NIH image J software in the computer (pO.05). The L4-5 intervertebral foraminal area decreased approximately 13% with each 1-mm incremental L4-5 disc space narrowing and simultaneous retrolisthesis of the L4 vertebra. CONCLUSIONS: There is a significant decrease in inferior foraminal area after disc space narrowing and simultaneous retrolisthesis of lumbar vertebra. The size of the intervertebral foramen is directly related to the degree of the disc degenerative changes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. CONFLICT OF INTEREST: No conflicts.
Study Design. Multidirectional flexibility tests were conducted on 10 human thoracic spines with ... more Study Design. Multidirectional flexibility tests were conducted on 10 human thoracic spines with intact rib cage. Objectives. To determine the amount of stability the rib cage imparts to the thoracic spine and to show the amount of stability lost by a sternal fracture. Summary of Background Data. There is no published study of biomechanical testing of human cadaveric specimens with the rib cage intact. Methods. In this study, 10 human cadaveric thoracic spines with the rib cage intact were tested using a biaxial material testing machine and an opto-electronic threedimensional motion measuring device (Opto-trak 3020). The specimens were tested in axial compression, axial rotation, lateral bending, and flexion/extension. First, the specimens were tested through all four loading types with the sternum and rib cage intact. Next, the sternum was fractured at the sternomanubrial junction displacing the proximal fragment posteriorly. Lastly, the entire rib cage was removed. Results. The rib cage increased the stability of the thoracic spine by 40% in flexion/extension (P ϭ 0.012), 35% in lateral bending (P ϭ 0.008), and 31% in axial rotation (P ϭ 0.008). An indirect flexion-compression type of sternal fracture decreased the stability of the thoracic spine by 42% in flexion/extension (P ϭ 0.036), 22% in lateral bending (P ϭ 0.038), and 15% in axial rotation (P ϭ 0.011). Conclusion. The rib cage significantly increases the stability of the thoracic spine in flexion/extension, lateral bending, and axial rotation. A sternal fracture significantly decreases the stability of the thorax.
Retrospectively, the MR (magnetic resonance) and contrast CT (computed tomography examinations of... more Retrospectively, the MR (magnetic resonance) and contrast CT (computed tomography examinations of 41 patients (123 segments) were objectively scored to evaluate spinal stenosis and disc degeneration. Five categories to evaluate stenosis included the facet joint, foramina, central canal, disc on sagittal section, and disc on axial section. In addition, the ability to demonstrate spondylolysis was compared. The examinations were interpreted by a single observer blinded to the results. Comparisons show 96.6% agreement between MR and contrast CT in the diagnosis of spinal stenosis. Magnetic resonance showed disc degeneration in 74 of 123 segments, while CT showed disc degeneration disease in 27 of 123 segments. Spondylolysis was recognized at three segments on both MR and CT. In conclusion, MR and contrast CT are comparable in their abilities to demonstrate spinal stenosis, and MR is more sensitive in demonstrating disc degeneration.
Journal of Toxicology and Environmental Health Sciences, Mar 31, 2011
The Buffalo Lupus Project was a community-based participatory research partnership formed to addr... more The Buffalo Lupus Project was a community-based participatory research partnership formed to address the relationship between an identified hazardous waste site and high rates of lupus and other autoimmune diseases in the surrounding community. Most cases identified began experiencing symptoms and were diagnosed in the periods when the site was inactive. Trends suggest that the impact of the site was more likely due to chronic exposure to waste rather than it being an acute trigger.
A geographic information assessment of exposure to a toxic waste site and development of systemic... more A geographic information assessment of exposure to a toxic waste site and development of systemic lupus erythematosus (SLE): Findings from the buffalo lupus project
International Journal of Sports Science and Coaching, 2008
A sample of 25 golfers, 12 professionals and 13 amateurs, ages 23 to 63 years, were measured for ... more A sample of 25 golfers, 12 professionals and 13 amateurs, ages 23 to 63 years, were measured for transverse plane pelvic rotation using light electrodes positioned bilaterally on the iliac crests. Transverse plane pelvic rotation was present in all of the golfers measured. All subjects were measured from a shoulder width stance, two inches wider and two inches narrower than shoulder width in a standing, erect posture and a golf setup posture without a club. Transverse plane pelvic rotation in the 25 subjects ranged from 1 inch to 4 inches as recorded by stance correction with an average of 2.25 inches of rotation at a shoulder width stance. A dowel pole bar with light electrodes fixed to the bar was attached to the transverse pelvic plane 3 inches below the iliac crest for the purpose of validation of a measurement instrument in the field. The pelvic rotation was temporarily corrected through a simple three minute exercise program. Nineteen of the 25 subjects were seen in follow-up in the field where the dowel bar was used and they had each returned to their measured baseline pelvic rotation. Again, their measured pelvic rotation was corrected via a simple three minute exercise program. The authors discuss the use of the exercise program for both golf coaching and research, and also present the validation of a simple instrument that could be used in the field to measure transverse pelvic plane rotation.
To describe the participatory approach used to develop ''Good For The Neighborhood'' (GFTN), a co... more To describe the participatory approach used to develop ''Good For The Neighborhood'' (GFTN), a community program to improve the health of four underserved communities. A core program was developed involving a ''park and stay'' approach to impact four underserved predominately minority communities (two predominately African American, 1 predominately Latino, and the Seneca Nation of Indians). The core program includes health screenings, risk assessments, health education, and exposure to health services. An extensive tracking and evaluation system was developed to determine participation and impact on the community. Multi-methods (key informant interviews, focus groups, surveys) were implemented to gain feedback from community partners and participants as to how to adopt the program to meet the needs of the community. GFTN has been sustained for over 3 years and has reached over 3,500 predominately minority individuals in four communities with 1/3 of participants engaging regularly in the program. The program has evolved in the four communities to meet specific needs. A ''park and stay'' approach in partnership with the community has led to a strong program that community partners and residents embrace. Community ownership and social networking, including word-of-mouth from residents is essential to establishing a successful program.
This study determines the impact of provider knowledge and attitude on implementation of guidelin... more This study determines the impact of provider knowledge and attitude on implementation of guidelines: spirometry, peak flows, patient assessments, action plans, severity assessment, and anti-inflammatories. A self-administered survey conducted in academic family practice sites in Buffalo, NY assessed knowledge, self-reported use, and perceived usefulness. Knowledge was associated with regular use of peak flows (p = 0.048) and anti-inflammatories (p = 0.01). Positive attitude was associated with regular use of spirometry (p = 0.03), peak flows (p < or = 0.001), patient assessments (p = 0.02), action plans (p = 0.046), anti-inflammatories (p < or = 0.001), and severity assessment (p < or = 0.001). Perceived usefulness is critical to implementing asthma guidelines. Interventions to improve provider adherence must address attitude.
This study presents an uncontrolled preliminary evaluation of a pilot health insurance subsidy pr... more This study presents an uncontrolled preliminary evaluation of a pilot health insurance subsidy program and addresses whether provision of subsidized insurance that required employee contribution had an impact upon preventive health utilization among small businesses and their employees. Self-report questionnaires were mailed to the employees; these included questions on use of preventive health services before and after enrollment in the subsidy program. The analysis was stratified by self-reported prior enrollment in an insurance program to compare employees with and without prior health insurance. The findings suggest significant increases in health service utilization among the previously uninsured. Regular checkups more than doubled (p < .0001), as did the number of individuals receiving regular blood work (p < .0001). Nearly twice the number of individuals filled regular prescriptions after enrollment in the subsidy program as compared with before (p…
Community-based participatory research (CBPR) is a mechanism to improve environmental quality in ... more Community-based participatory research (CBPR) is a mechanism to improve environmental quality in communities primarily inhabited by minorities or low income families. A collaborative partnership between the University at Buffalo and the Toxic Waste Lupus Coalition was formed to investigate the high prevalence of lupus in the area and whether cases of disease were linked to chemicals found at a nearby New York State Superfund site in East Buffalo. The purpose of the study was to use CBPR practices to educate impacted residents and enable their participation in efforts to get a nearby contaminated waste site remediated. Community members were active participants in the development of the plan to clean up the toxic site. These methods can be used to better engage the community in research and involve them in actions taken to improve their neighborhood.
Complications of anterior lumbar fusion may be divided into several categories. The first of thes... more Complications of anterior lumbar fusion may be divided into several categories. The first of these is complications related to patient selection, the second is visceral complications, and the third is vascular complications. Complications of anterior lumbar fusion and complications of interbody fusion technique occur at the graft site and the donor site. Patient selection is very i m p~r t a n t .~ The patient's preoperative findings must indicate that the benefit of anterior surgery outweighs the potential complications. The proper approach for each individual patient must be planned. The standard leftsided oblique or transverse skin incision for L5-S1 should point toward the midline at the junction of the distal and middle third of the distance between the umbilicus and the pubis; for L4-L5, it should be the junction of the proximal and middle third. The danger is usually not being low enough. Dissection from caudal to cephalad is usually easier than cephalad to caudal, especially when there is a significant amount of lumbar lordosis and the disk space is angled caudally anteriorly. This makes visualization of the posterior aspect of the disk space difficult. For cases with extreme lumbar lordosis, one way of avoiding this inability to visualize the disk space is to use a vertical midline or pararectus From the Kerlan-Jobe Orthopaedic Clinic, Las An-Reprint requests to
Sequential rhetoric can serve as a framework to instruct UX practice (through user story maps) to... more Sequential rhetoric can serve as a framework to instruct UX practice (through user story maps) to new learners because it is both approachable and affordable. Sequential rhetoric consists of five main facets that incorporate planning elements (core visual writing and envisaging) and composing elements (interanimation, juxtaquencing, and gestalt closure), which this essay both defines and relates to convergent scholarship. We argue that sequential rhetoric transfers beyond the technical classroom and into the profession itself.
Proceedings of SPE Annual Fall Technical Conference and Exhibition, 1978
Past research in miscible flooding has indicated some residual oil may be left in carbon dioxide ... more Past research in miscible flooding has indicated some residual oil may be left in carbon dioxide swept rock as a result of CO2-oil phase behavior, rock pore structure, or mobile water saturation. Determination of the magnitude of this residual oil saturation in the reservoir rock of interest is important when a field is evaluated for CO2 miscible flooding. However, miscible displacements in laboratory outcrop cores sometimes exhibit a length effect, suggesting that reservoir rock samples as long as ten feet or greater may be required for the determination of the true unit displacement efficiency. This paper describes the development of a technique allowing the measurement of CO2 unit displacement efficiency in short core system consisting of either actual reservoir rock or outcrop sandstones. A number of core floods were performed under varying conditions in which continuously injected CO2 displaced a synthesized reservoir fluid from 15- to 30-cm long Berea sandstone cores and low permeability carbonate cores from a West Texas permeability carbonate cores from a West Texas reservoir. For secondary and tertiary recovery floods in both core types, residual oil saturations comparable to those reported for long sandstone systems were observed when solvent fingering was controlled. Length and rate effects previously observed are demonstrated to depend primarily on solvent sweep efficiency rather than the mechanism for achieving miscibility. The current as well as previous studies show that gravity, transverse dispersion, and viscosity gradation may each be effective stabilizing mechanisms under appropriate conditions. This work allows the relative importance of each to be estimated in a core flood and for the first time their combined influence correlated with the measured overall displacement efficiency. Two methods are described and shown to be effective for generating the viscosity graded CO2-oil transition zone required for flood stabilization when gravity and transverse dispersion are relatively unimportant, as in short, low permeability reservoir core samples. Based on these concepts, laboratory CO2 floods may be designed to prevent viscous fingering now enabling measurement of the true CO2 unit displacement efficiency in short laboratory systems. Introduction Carbon dioxide miscible flooding is one of the more promising processes for enhanced oil recovery. Evaluation of prospects for full-scale CO2 flooding requires a thorough understanding of recovery behavior. Unit displacement efficiency is an important factor in such an evaluation and, because unit displacement efficiency may depend on rock and fluid properties, core displacement tests in actual properties, core displacement tests in actual reservoir rock using realistic reservoir fluids may be necessary for the evaluation of each candidate reservoir. This paper describes a technique for flooding short pieces of reservoir rock containing reservoir fluids at reservoir temperature to determine the residual oil saturation left in the fully-swept rock. Very few CO2 miscible displacement tests have been performed in the past using actual reservoir rock. Instead, most laboratory studies of CO2 flooding (as well as with LPG and other solvents) have been conducted using outcrop sandstone cores. Berea, Boise and Torpedo sandstones were chosen due to their availability and uniformity. These sandstones can be cut easily into lengths of approximately 10 ft, and much longer systems for displacement studies can be constructed by butting cores together. Reservoir rock, on the other hand, must be obtained from oil-field core samples. Lengths of reservoir rock for laboratory flooding are limited to several feet at most for stacked cores and to considerably less for single cores. A wide variation in the apparent residual oil saturation left to miscible flooding, Sor, has been observed in laboratory displacements with both CO2 above the multi-contact miscibility pressure and with first-contact miscible fluids even when similar porous media were used. porous media were used.
Community-based participatory research requires the participation of community stakeholders to in... more Community-based participatory research requires the participation of community stakeholders to inform the process. The West Side Community Asthma Project, a community-based participatory research program to study the effects of the environment on asthma conducted in Buffalo, N. Y., identified a stakeholders group of community leaders and activists. Creative strategies have been implemented to reach out to other community residents to invite them to participate in the participatory process. Community-based participatory research has been defined as "a collaborative approach to research that equitably involves all partners in the research process and recognizes the unique strengths that each brings. Community-based participatory research begins with a research topic of importance to the community and has the aim of combining knowledge with action and achieving social change to improve health outcomes and eliminate health disparities."(Community Health Scholars Program, 2004)
BACKGROUND CONTEXT: Andriacchi performed a computer-simulated mathematical analysis showing that ... more BACKGROUND CONTEXT: Andriacchi performed a computer-simulated mathematical analysis showing that the rib cage enhances stability of the normal thoracic spine in flexion, rotation, lateral bending, and especially extension. He showed an increase of 27 per cent in flexion and of 132 percent in extension with the addition of the rib cage. Panjabi and White established criteria assessing stability in the thoracic spine by performing studies supporting the stabilizing role of the costovertebral joints. However, these experiments underestimated the role of the rib cage because the ribs were removed 3 cm lateral to the costovertebral joints. Recently, Oda et al. showed significant increases in the neutral zone in lateral bending and axial rotation after resection of the costovertebral joints and destruction of the rib cage. The limitation to this study was the use of canine specimens rather than human. There is no published study of biomechanical testing of human cadaveric specimens with the rib cage intact. PURPOSE: To determine the amount of stability the rib cage imparts to the thoracic spine and to show the amount of stability lost by a sternal fracture. STUDY DESIGN/SETTING: Specimens were tested using a biaxial material testing machine (MTS) synchronized with an opto-electronic three-dimensional motion measuring device (Opto-trak 3020). PATIENT SAMPLE: Ten fresh-frozen human cadaveric thoracic spines with the rib cage and sternum intact. OUTCOME MEASURES: Multidirectional flexibility of the whole thoracic spine was measured using the Optotrak 3020, an opto-electronic threedimensional motion measuring device. This machine uses three cameras to detect movement of multiplexed arrays of light emiting diodes (LEDs). An array attached to the MTS machine established the fixed coordinate axes. One array was attached to T1 by way of a rigid pin placed in the pedicle. With T12 rigidly fixed to the base of the MTS system, motion of the T1 array represented motion of the entire thoracic spine specimen. METHODS: The specimens were tested in axial compression, axial rotation, lateral bending, and flexion/extension. First, the specimens were tested through all four loading types with the sternum and rib cage intact. Next, the sternum was fractured at the sternomanubrial junction displacing the proximal fragment posteriorly. Lastly, the entire rib cage was removed by cutting the ribs 3 cm lateral to the costovertebral joints. RESULTS: The rib cage increased the stability of the thoracic spine by 40% in flexion/extension (pϭ.012), 35% in lateral bending (pϭ.038), and 31% in axial rotation (pϭ.008). An indirect flexion-compression type of sternal fracture decreased the stability of the thoracic spine by 42% in flexion/extension (pϭ.036), 22% in lateral bending (pϭ.008), and 15% in axial rotation (pϭ.011). CONCLUSIONS: The rib cage significantly increases the stability of the thoracic spine in flexion/extension, lateral bending, and axial rotation. A sternal fracture significantly decreases the stability of the thorax. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: Author (RWI) Other: Synthes, Sofamor-Danek, Depuy, and Blackstone all contributed monetary funds to pay for the materials of this project.
Retrospective radiographic analysis.To determine the fusion rate of stand-alone lateral lumbar in... more Retrospective radiographic analysis.To determine the fusion rate of stand-alone lateral lumbar interbody fusion (LLIF).Biomechanical studies have indicated that LLIF may be more stable than anterior or transforaminal lumbar interbody fusion. Early clinical reports of stand-alone LLIF have shown success in obtaining fusion and indirectly decompressing nerve roots.A consecutive case series of stand-alone LLIF was analyzed with chart and radiographic review. Non-union was determined by symptomatology consistent with non-union and absence of bridging bone on the CT scan.Thirty-nine levels of stand alone LLIF were performed in 23 patients. Eleven patients received 1-level surgery, 7 patients received 2-level surgery, 3 patients received 3-level surgery, and 1 patient received 4-level surgery. Excluding 1 infected case, we analyzed 37 levels of stand alone LLIF in 22 patients. Non-union incidence was 7 levels in 6 patients. Non-union rate was 7/37 (19%) per level and 6/22 (27%) per patien...
retrolisthesis of L4 vertebra were analyzed with the Student t test. The confidence level for sig... more retrolisthesis of L4 vertebra were analyzed with the Student t test. The confidence level for significance was pOT0.05. RESULTS: The mean cross-sectional area of the L4-5 intervertebral foramen of the anatomic spine was 171.70636.38 mm 2 at the left side and 170.68637.28 mm 2 at the right side. No significant difference was found between the left and right sides (pO.05). No significant difference was found between the measured values using Aquarius Image software of the CT scanner and NIH image J software in the computer (pO.05). The L4-5 intervertebral foraminal area decreased approximately 13% with each 1-mm incremental L4-5 disc space narrowing and simultaneous retrolisthesis of the L4 vertebra. CONCLUSIONS: There is a significant decrease in inferior foraminal area after disc space narrowing and simultaneous retrolisthesis of lumbar vertebra. The size of the intervertebral foramen is directly related to the degree of the disc degenerative changes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. CONFLICT OF INTEREST: No conflicts.
Study Design. Multidirectional flexibility tests were conducted on 10 human thoracic spines with ... more Study Design. Multidirectional flexibility tests were conducted on 10 human thoracic spines with intact rib cage. Objectives. To determine the amount of stability the rib cage imparts to the thoracic spine and to show the amount of stability lost by a sternal fracture. Summary of Background Data. There is no published study of biomechanical testing of human cadaveric specimens with the rib cage intact. Methods. In this study, 10 human cadaveric thoracic spines with the rib cage intact were tested using a biaxial material testing machine and an opto-electronic threedimensional motion measuring device (Opto-trak 3020). The specimens were tested in axial compression, axial rotation, lateral bending, and flexion/extension. First, the specimens were tested through all four loading types with the sternum and rib cage intact. Next, the sternum was fractured at the sternomanubrial junction displacing the proximal fragment posteriorly. Lastly, the entire rib cage was removed. Results. The rib cage increased the stability of the thoracic spine by 40% in flexion/extension (P ϭ 0.012), 35% in lateral bending (P ϭ 0.008), and 31% in axial rotation (P ϭ 0.008). An indirect flexion-compression type of sternal fracture decreased the stability of the thoracic spine by 42% in flexion/extension (P ϭ 0.036), 22% in lateral bending (P ϭ 0.038), and 15% in axial rotation (P ϭ 0.011). Conclusion. The rib cage significantly increases the stability of the thoracic spine in flexion/extension, lateral bending, and axial rotation. A sternal fracture significantly decreases the stability of the thorax.
Retrospectively, the MR (magnetic resonance) and contrast CT (computed tomography examinations of... more Retrospectively, the MR (magnetic resonance) and contrast CT (computed tomography examinations of 41 patients (123 segments) were objectively scored to evaluate spinal stenosis and disc degeneration. Five categories to evaluate stenosis included the facet joint, foramina, central canal, disc on sagittal section, and disc on axial section. In addition, the ability to demonstrate spondylolysis was compared. The examinations were interpreted by a single observer blinded to the results. Comparisons show 96.6% agreement between MR and contrast CT in the diagnosis of spinal stenosis. Magnetic resonance showed disc degeneration in 74 of 123 segments, while CT showed disc degeneration disease in 27 of 123 segments. Spondylolysis was recognized at three segments on both MR and CT. In conclusion, MR and contrast CT are comparable in their abilities to demonstrate spinal stenosis, and MR is more sensitive in demonstrating disc degeneration.
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