This article discusses how all new toll roads in the U.S. are being built with electronic toll ex... more This article discusses how all new toll roads in the U.S. are being built with electronic toll express (ETX) lanes featuring automated toll collection systems. It gives an overview of various regions in the U.S. where automated toll collection has been successfully implemented.
This paper describes how design, planning and pricing should all be used to improve highway trave... more This paper describes how design, planning and pricing should all be used to improve highway travel. Traffic congestion can best be remedied by managed lanes. The author argues that roads should be funded with money that users pay directly for service rather than through the conventional tax-and-grant system. When customers are prepared to pay tolls sufficient to fund extra capacity, it is economically efficient to provide it. Highway design features such as elevated expressways and better use of rights of way can also reduce congestion and make highway travel more tolerable. Mixed-use highways, designed for all types of vehicles, have constrained the ability to add needed capacity to the urban expressway. Separating car and truck traffic would offer many benefits, including allowing car-only parkways to be built with narrower lanes and lower overhead clearance. These parkways would also make for a more pleasant and safer trip.
This article describes plans for using motorists' mobile phones as a source of traveler infor... more This article describes plans for using motorists' mobile phones as a source of traveler information services and traffic management data. Vehicles traveling on the Washington Beltway in norther Virginia and Maryland will be used as probe vehicles, providing a way to monitor traffic. The article also describes how other technologies are used as probes, making speed estimates and detecting incidents and congestion.
In November 2006 a shortfall was identified in funding for Pennsylvania's transportation infr... more In November 2006 a shortfall was identified in funding for Pennsylvania's transportation infrastructure and public transit services. An additional $65 million is needed for local highways and bridges, $900 million for state highways and bridges, and $700 million for public transit, annually. One option for increasing the funding for transportation infrastructure is to lease the Pennsylvania Turnpike. The Turnpike could be leased to generate significant revenue to help meet the transportation needs of Pennsylvania. However, this proposal to lease the turnpike has run into strong opposition. This paper takes each point that critics have proposed and offers counter arguments for the implementation of a public private partnership that would benefit Pennsylvania's transportation infrastructure.
This article gives an overview of the first free-standing, multi- interchange toll facility that ... more This article gives an overview of the first free-standing, multi- interchange toll facility that will rely solely on electronic computers for toll payment. Located in Houston, Texas, The Westpark Tollway will have no provisions for cash payments.
This article describes the OnStar Global Positioning System (GPS)/ cellphone emergency system off... more This article describes the OnStar Global Positioning System (GPS)/ cellphone emergency system offered by Cadillac. The system is capable of providing the following features: roadside assistance with location, emergency services, routing and location assistance, airbag deployment notification, remote door unlock, theft detection/notification and stolen- vehicle tracking, information on convenience services, and hands-free voice-activated cellular phone.
A powerful statistical method was designed using JMP software to detect factors contributing to d... more A powerful statistical method was designed using JMP software to detect factors contributing to differences in the dissolution process of an antiviral drug delivered in an oral dosage form. Due to the large number of dissolution media available for solid dosage forms, a statistical method to choose the appropriate medium is critical for testing solid dosage forms. We have developed an analysis of variance model to analyze the overall dissolution profile obtained from the various media. In vitro tests were performed using a standard USP basket apparatus (Vankel Inc., Cary, NC), and the analysis used the restricted/residual maximum likelihood method (JMP software) to partition the variance due to media (pH 1.2 and 6.8, +SDS, water alone and at pH 1.2 with pepsin), time (repeated measure) and capsule (random effect). This allowed correct standard error estimates to be used to compare dissolution in different media using planned linear contrasts. The model provided us with statistically powerful criteria to identify significant differences in capsule dissolution across time and to quantify capsule-to-capsule population variance estimate. The time specific linear contrasts showed the largest sum of square values (SS) occurred at 180 min (SS=0.268) for the simulated SIF (pH 6.8) versus SGF (pH 1.2) comparison (DF=166, MSE=3.92 x 10(-3)). The dissolution processes were further characterized using a non-linear regression fit of a power law function to the data for each capsule. This resulted in a method to statistically differentiate between the dissolution processes of the capsules in different media.
1. Introduction: Themes and Issues 2. Multiple-methods, One Sector, Four Cases and One Union 3. S... more 1. Introduction: Themes and Issues 2. Multiple-methods, One Sector, Four Cases and One Union 3. Structural Origins 4. Management and Workplace Union Motives 5. Form 6. Employer Outcomes 7. Union and Worker Outcomes 8. Conclusion: The Dynamics of Partnership
Home Contact Us Directory E-Newsletter Follow Us RSS, About TRB. Annual Meeting. Calendar. Commit... more Home Contact Us Directory E-Newsletter Follow Us RSS, About TRB. Annual Meeting. Calendar. Committees & Panels. Programs. Projects. Publications. Resources & Databases. TRID HOME. RECENTLY PUBLISHED. RECENTLY ADDED. ADVANCED SEARCH. ...
The authors present their initial experience of a new sterile medical grade cyanoacrylate adhesiv... more The authors present their initial experience of a new sterile medical grade cyanoacrylate adhesive (Indermil) in otolaryngeal and head and neck surgery.Thirty-three patients who underwent a variety of head and neck operations consented to have their skin incisions closed using the adhesive and 10 of those also underwent repair of the tympanic membrane, either as part of tympanoplasty or mastoid surgery. The history of the use of this class of adhesive is presented with an explanation of the chemical properties of these compounds. Advantages of using cyanoacrylate adhesives and future possible applications in otolaryngology and head and neck surgery are discussed.
We report the cases of two laryngectomy patients who were diagnosed with de novo nasal polyposis,... more We report the cases of two laryngectomy patients who were diagnosed with de novo nasal polyposis, more than 15 years after their laryngectomies. This phenomenon has not previously been reported in the literature. We discuss the changes in nasal physiology of the laryngectomy patient, with regards to the aetiology of polyp formation, and highlight the importance of examining the nose in such patients.
Abnormal sensitivity to environmental sounds is a short-term feature often observed following ins... more Abnormal sensitivity to environmental sounds is a short-term feature often observed following insertion of grommets. Here we describe a child with this symptom who was found to have Williams syndrome, a condition in which hyperacusis is observed in 95 per cent of patients.
Several proteases are capable of hydrolyzing the aryl substituted phosphoramidate derivatives of ... more Several proteases are capable of hydrolyzing the aryl substituted phosphoramidate derivatives of stavudine resulting in the formation of the active metabolite, alaninyl d4T monophosphate. Subtilisin Protease A, Subtilisin Griseus, Subtilisin Carlsberg, Papaya, Bacillus were amongst the most effective proteases in hydrolyzing stavudine derivatives and specificity of their activity was confirmed using several protease inhibitors to block the hydrolysis of these phosphoramidate derivatives. We found that these proteases exhibit chiral selectivity at the phosphorus center of stavudine derivatives. Our results indicate that cellular proteases may be responsible for the activation of these phosphoramidate derivatives. In addition, we show that the enzymatic hydrolysis takes place at the carboxymethyl ester side chain of these pro-drugs and the direct attack on the phosphorus center by these enzymes does not occur. Finally, we describe a novel activation pathway hitherto unknown for the activation and viral inhibitory characteristic shown by these phosphoramidate derivatives of stavudine.
Stampidine and other halogen substituted stavudine phosphoramidates can be activated by lipase-me... more Stampidine and other halogen substituted stavudine phosphoramidates can be activated by lipase-mediated hydrolysis. The target site for the lipase appears to be the methyl ester group of the L-alanine side chain. Accordingly, the D-amino acid substituted isomers {Rp or Sp}are resistant to lipase-mediated hydrolysis and exhibit substantially less anti-HIV activity. Molecular modeling results indicate that the L-amino acid configured isomers {Rp or Sp} are preferred in the lipase binding pocket.
Enzymatic hydrolysis of stampidine and other aryl phosphate derivatives of stavudine were investi... more Enzymatic hydrolysis of stampidine and other aryl phosphate derivatives of stavudine were investigated using the Candida Antarctica Type B lipase. Modeling studies and comparison of the hydrolysis rate constants revealed a chiral preference of the lipase active site for the putative S-stereoisomer. The in vitro anti-HIV activity of these compounds correlated with their susceptibility to lipase- (but not esterase-) mediated hydrolysis. We propose that stampidine undergoes rapid enzymatic hydrolysis in the presence of lipase according to the following biochemical pathway: During the first step, hydrolysis of the ester group results in the formation of carboxylic acid. Subsequent step involves an intramolecular cyclization at the phosphorous center with simultaneous elimination of the phenoxy group to form a cyclic intermediate. In the presence of water, this intermediate is converted into the active metabolite Ala-d4T-MP. We postulate that the lipase hydrolyzes the methyl ester group of the l-alanine side chain to form the cyclic intermediate in a stereoselective fashion. This hypothesis was supported by experimental data showing that chloroethyl substituted derivatives of stampidine, which possess a chloroethyl linker unit instead of a methyl ester side chain, were resistant to lipase-mediated hydrolysis, which excludes the possibility of a direct hydrolysis of stampidine at the phosphorous center. Thus, our model implies that the lipase-mediated formation of the cyclic intermediate is a key step in metabolism of stampidine and relies on the initial configuration of the stereoisomers.
Changing the nucleoside group of a series of phosphoramidate derivatives affects the enzyme media... more Changing the nucleoside group of a series of phosphoramidate derivatives affects the enzyme mediated hydrolysis rate of the compounds. d4T and AZT-substituted analogs were activated by enzymes such as lipases, esterases, and proteases. On the other hand, 3dT-substituted derivatives were comparatively less prone to hydrolysis under similar experimental conditions. From the experimental results, we propose that the most preferable nucleoside group for enzyme activation is d4T rather than AZT or 3dT. Additionally, we also observed that depending on the enzymes used the chiral selectivity of the enzymes for the phosphorus center of these phosphoramidate derivatives differed, demonstrating the importance of the nucleoside structure for this class of compounds.
In little more than 12 months, beginning in late 2004, the following events occurred: A Spanish t... more In little more than 12 months, beginning in late 2004, the following events occurred: A Spanish toll road company proposed to invest $7.2 billion to build the first leg of the Trans-Texas Corridor (TTC), a major highway, rail, and utility corridor running north-south from Oklahoma to ...
This article discusses how all new toll roads in the U.S. are being built with electronic toll ex... more This article discusses how all new toll roads in the U.S. are being built with electronic toll express (ETX) lanes featuring automated toll collection systems. It gives an overview of various regions in the U.S. where automated toll collection has been successfully implemented.
This paper describes how design, planning and pricing should all be used to improve highway trave... more This paper describes how design, planning and pricing should all be used to improve highway travel. Traffic congestion can best be remedied by managed lanes. The author argues that roads should be funded with money that users pay directly for service rather than through the conventional tax-and-grant system. When customers are prepared to pay tolls sufficient to fund extra capacity, it is economically efficient to provide it. Highway design features such as elevated expressways and better use of rights of way can also reduce congestion and make highway travel more tolerable. Mixed-use highways, designed for all types of vehicles, have constrained the ability to add needed capacity to the urban expressway. Separating car and truck traffic would offer many benefits, including allowing car-only parkways to be built with narrower lanes and lower overhead clearance. These parkways would also make for a more pleasant and safer trip.
This article describes plans for using motorists' mobile phones as a source of traveler infor... more This article describes plans for using motorists' mobile phones as a source of traveler information services and traffic management data. Vehicles traveling on the Washington Beltway in norther Virginia and Maryland will be used as probe vehicles, providing a way to monitor traffic. The article also describes how other technologies are used as probes, making speed estimates and detecting incidents and congestion.
In November 2006 a shortfall was identified in funding for Pennsylvania's transportation infr... more In November 2006 a shortfall was identified in funding for Pennsylvania's transportation infrastructure and public transit services. An additional $65 million is needed for local highways and bridges, $900 million for state highways and bridges, and $700 million for public transit, annually. One option for increasing the funding for transportation infrastructure is to lease the Pennsylvania Turnpike. The Turnpike could be leased to generate significant revenue to help meet the transportation needs of Pennsylvania. However, this proposal to lease the turnpike has run into strong opposition. This paper takes each point that critics have proposed and offers counter arguments for the implementation of a public private partnership that would benefit Pennsylvania's transportation infrastructure.
This article gives an overview of the first free-standing, multi- interchange toll facility that ... more This article gives an overview of the first free-standing, multi- interchange toll facility that will rely solely on electronic computers for toll payment. Located in Houston, Texas, The Westpark Tollway will have no provisions for cash payments.
This article describes the OnStar Global Positioning System (GPS)/ cellphone emergency system off... more This article describes the OnStar Global Positioning System (GPS)/ cellphone emergency system offered by Cadillac. The system is capable of providing the following features: roadside assistance with location, emergency services, routing and location assistance, airbag deployment notification, remote door unlock, theft detection/notification and stolen- vehicle tracking, information on convenience services, and hands-free voice-activated cellular phone.
A powerful statistical method was designed using JMP software to detect factors contributing to d... more A powerful statistical method was designed using JMP software to detect factors contributing to differences in the dissolution process of an antiviral drug delivered in an oral dosage form. Due to the large number of dissolution media available for solid dosage forms, a statistical method to choose the appropriate medium is critical for testing solid dosage forms. We have developed an analysis of variance model to analyze the overall dissolution profile obtained from the various media. In vitro tests were performed using a standard USP basket apparatus (Vankel Inc., Cary, NC), and the analysis used the restricted/residual maximum likelihood method (JMP software) to partition the variance due to media (pH 1.2 and 6.8, +SDS, water alone and at pH 1.2 with pepsin), time (repeated measure) and capsule (random effect). This allowed correct standard error estimates to be used to compare dissolution in different media using planned linear contrasts. The model provided us with statistically powerful criteria to identify significant differences in capsule dissolution across time and to quantify capsule-to-capsule population variance estimate. The time specific linear contrasts showed the largest sum of square values (SS) occurred at 180 min (SS=0.268) for the simulated SIF (pH 6.8) versus SGF (pH 1.2) comparison (DF=166, MSE=3.92 x 10(-3)). The dissolution processes were further characterized using a non-linear regression fit of a power law function to the data for each capsule. This resulted in a method to statistically differentiate between the dissolution processes of the capsules in different media.
1. Introduction: Themes and Issues 2. Multiple-methods, One Sector, Four Cases and One Union 3. S... more 1. Introduction: Themes and Issues 2. Multiple-methods, One Sector, Four Cases and One Union 3. Structural Origins 4. Management and Workplace Union Motives 5. Form 6. Employer Outcomes 7. Union and Worker Outcomes 8. Conclusion: The Dynamics of Partnership
Home Contact Us Directory E-Newsletter Follow Us RSS, About TRB. Annual Meeting. Calendar. Commit... more Home Contact Us Directory E-Newsletter Follow Us RSS, About TRB. Annual Meeting. Calendar. Committees & Panels. Programs. Projects. Publications. Resources & Databases. TRID HOME. RECENTLY PUBLISHED. RECENTLY ADDED. ADVANCED SEARCH. ...
The authors present their initial experience of a new sterile medical grade cyanoacrylate adhesiv... more The authors present their initial experience of a new sterile medical grade cyanoacrylate adhesive (Indermil) in otolaryngeal and head and neck surgery.Thirty-three patients who underwent a variety of head and neck operations consented to have their skin incisions closed using the adhesive and 10 of those also underwent repair of the tympanic membrane, either as part of tympanoplasty or mastoid surgery. The history of the use of this class of adhesive is presented with an explanation of the chemical properties of these compounds. Advantages of using cyanoacrylate adhesives and future possible applications in otolaryngology and head and neck surgery are discussed.
We report the cases of two laryngectomy patients who were diagnosed with de novo nasal polyposis,... more We report the cases of two laryngectomy patients who were diagnosed with de novo nasal polyposis, more than 15 years after their laryngectomies. This phenomenon has not previously been reported in the literature. We discuss the changes in nasal physiology of the laryngectomy patient, with regards to the aetiology of polyp formation, and highlight the importance of examining the nose in such patients.
Abnormal sensitivity to environmental sounds is a short-term feature often observed following ins... more Abnormal sensitivity to environmental sounds is a short-term feature often observed following insertion of grommets. Here we describe a child with this symptom who was found to have Williams syndrome, a condition in which hyperacusis is observed in 95 per cent of patients.
Several proteases are capable of hydrolyzing the aryl substituted phosphoramidate derivatives of ... more Several proteases are capable of hydrolyzing the aryl substituted phosphoramidate derivatives of stavudine resulting in the formation of the active metabolite, alaninyl d4T monophosphate. Subtilisin Protease A, Subtilisin Griseus, Subtilisin Carlsberg, Papaya, Bacillus were amongst the most effective proteases in hydrolyzing stavudine derivatives and specificity of their activity was confirmed using several protease inhibitors to block the hydrolysis of these phosphoramidate derivatives. We found that these proteases exhibit chiral selectivity at the phosphorus center of stavudine derivatives. Our results indicate that cellular proteases may be responsible for the activation of these phosphoramidate derivatives. In addition, we show that the enzymatic hydrolysis takes place at the carboxymethyl ester side chain of these pro-drugs and the direct attack on the phosphorus center by these enzymes does not occur. Finally, we describe a novel activation pathway hitherto unknown for the activation and viral inhibitory characteristic shown by these phosphoramidate derivatives of stavudine.
Stampidine and other halogen substituted stavudine phosphoramidates can be activated by lipase-me... more Stampidine and other halogen substituted stavudine phosphoramidates can be activated by lipase-mediated hydrolysis. The target site for the lipase appears to be the methyl ester group of the L-alanine side chain. Accordingly, the D-amino acid substituted isomers {Rp or Sp}are resistant to lipase-mediated hydrolysis and exhibit substantially less anti-HIV activity. Molecular modeling results indicate that the L-amino acid configured isomers {Rp or Sp} are preferred in the lipase binding pocket.
Enzymatic hydrolysis of stampidine and other aryl phosphate derivatives of stavudine were investi... more Enzymatic hydrolysis of stampidine and other aryl phosphate derivatives of stavudine were investigated using the Candida Antarctica Type B lipase. Modeling studies and comparison of the hydrolysis rate constants revealed a chiral preference of the lipase active site for the putative S-stereoisomer. The in vitro anti-HIV activity of these compounds correlated with their susceptibility to lipase- (but not esterase-) mediated hydrolysis. We propose that stampidine undergoes rapid enzymatic hydrolysis in the presence of lipase according to the following biochemical pathway: During the first step, hydrolysis of the ester group results in the formation of carboxylic acid. Subsequent step involves an intramolecular cyclization at the phosphorous center with simultaneous elimination of the phenoxy group to form a cyclic intermediate. In the presence of water, this intermediate is converted into the active metabolite Ala-d4T-MP. We postulate that the lipase hydrolyzes the methyl ester group of the l-alanine side chain to form the cyclic intermediate in a stereoselective fashion. This hypothesis was supported by experimental data showing that chloroethyl substituted derivatives of stampidine, which possess a chloroethyl linker unit instead of a methyl ester side chain, were resistant to lipase-mediated hydrolysis, which excludes the possibility of a direct hydrolysis of stampidine at the phosphorous center. Thus, our model implies that the lipase-mediated formation of the cyclic intermediate is a key step in metabolism of stampidine and relies on the initial configuration of the stereoisomers.
Changing the nucleoside group of a series of phosphoramidate derivatives affects the enzyme media... more Changing the nucleoside group of a series of phosphoramidate derivatives affects the enzyme mediated hydrolysis rate of the compounds. d4T and AZT-substituted analogs were activated by enzymes such as lipases, esterases, and proteases. On the other hand, 3dT-substituted derivatives were comparatively less prone to hydrolysis under similar experimental conditions. From the experimental results, we propose that the most preferable nucleoside group for enzyme activation is d4T rather than AZT or 3dT. Additionally, we also observed that depending on the enzymes used the chiral selectivity of the enzymes for the phosphorus center of these phosphoramidate derivatives differed, demonstrating the importance of the nucleoside structure for this class of compounds.
In little more than 12 months, beginning in late 2004, the following events occurred: A Spanish t... more In little more than 12 months, beginning in late 2004, the following events occurred: A Spanish toll road company proposed to invest $7.2 billion to build the first leg of the Trans-Texas Corridor (TTC), a major highway, rail, and utility corridor running north-south from Oklahoma to ...
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