Interchange fees in various countries: developments and determinants

Interchange fees and related issues in credit and debit card markets have been the focus of considerable attention in recent years. The academic community has begun to address the economics of these markets. Public officials have begun to address the policy implications of developments in these markets. Meanwhile, these markets continue to experience dynamic change as credit, and especially debit, transactions account for an ever-growing share of overall payments. This paper provides an overview of interchange fee developments and issues in a number of countries. It also presents a preliminary analysis of some possible contributing factors. The principal conclusion of the paper is that interchange arrangements vary considerably across countries, and while existing economic theory provides some insight into fee levels and movements, much remains to be explained. A number of complex and interrelated factors, many country-specific, play a role in interchange developments.Credit cards ; Debit cards

Interchange fees in various countries : developments and determinants

Debit cards ; Credit cards

Scientific solutions for regulatory guidelines: Unlocking AAV product testing

Recombinant adeno-associated virus (rAAV) represents over 65% of viral vectors being developed for gene therapy applications today. Whilst the use of rAAV is attractive as a vehicle for gene delivery, the regulatory pathway and vector manufacturing processes are complex. Through CMC guidance documents issued in 2020, the FDA recommend that characterization of gene therapy products to determine Critical Quality Attributes (CQA) is evaluated as early as possible in pre and early clinical phases. Drug Developers need high quality orthogonal analytical methods to address specific concerns for AAV products with respect to potency (titre); characterization of the capsid such as understanding Full: Empty capsid ratio and determination of aggregation and product stability, which require multiplexed assays and novel analytical technologies. For Process Developers, focus on safety, product & process impurity profiles are paramount as the traditional viral vector manufacturing methods of viral removal such as low pH or demonstration of removal of potential contaminating virus by viral clearance validation studies are not possible. Above all, the rAAV product must not be capable of replication in vitro, and the absence of replication competent AAV must be demonstrated to alleviate any safety concerns. How then can you minimise the burden of AAV product characterization whilst maximizing the information generated? This conference talk will discuss the selection of analytical methodologies that answers this question, focusing on the development of analytic techniques to determine the critical quality attributes of aggregation and product stability

Lyophilisation of lentiviral pseudotypes for the development and distribution of virus neutralisation assay kits for rabies, Marburg and influenza viruses

Purpose: Some conventional serological assays can accurately quantify neutralising antibody responses raised against epitopes on virus glycoproteins, enabling mass vaccine evaluation and serosurveillance studies to take place. However, these assays often necessitate the handling of wild-type virus in expensive high biosafety laboratories, which restricts the scope of their application, particularly in resource-deprived areas. A solution to this issue is the use of lentiviral pseudotype viruses (PVs)—chimeric, replication-deficient virions that imitate the binding and entry mechanisms of their wild-type equivalents. Pseudotype virus neutralisation assays (PVNAs) bypass high biosafety requirements and yield comparable results to established assays. This study explores the potential for using lyophilisation of pseudotypes as a cost-effective, alternative means for production, distribution and storage of a PVNAbased diagnostic kit. Methods & Materials: Rabies, Marburg and H5 subtype Influenza virus pseudotypes were each suspended in cryoprotectant solutions of various molarities and subjected to freeze-drying before incubation at a variety of temperatures, humidities and time periods. Samples were then employed in antibody neutralisation assays using specific sera. Results: High levels of PV titre were retained post-lyophilisation, with acceptable levels of virus activity maintained even after medium-term storage in tropical conditions. Also, the performance of PVs in neutralisation assays was not affected by the lyophilisation process. Conclusion: These results confirm the viability of a freeze-dried PVNA-based diagnostic kit, which could considerably facilitate in-field serology for a number of clinically important viruses

Geospatial Analysis of Weathering and Recession on Architectural Limestone at the 1891 Powerhouse/Icehouse in Eureka Springs, Arkansas

The objective of this study of the architectural limestone of the 1891 Powerhouse/Icehouse in Eureka Springs, Arkansas was to analyze the environmental factors that influenced the deterioration and surface recession of this historical stone structure. The focus of this research was to examine and establish a baseline study that may assist in future monitoring and documentation of this historic limestone structure on stone weathering. A replicable methodology was specifically created toward this baseline research in hopes that it represented a solid baseline study. Observations and data analyses revealed the relationship between the architectural limestone building structure and the dominating recession of natural and anthropogenic factors. The findings revealed two primary variables in accelerating surface recession: (a) aspect – as a surrogate measurement for insolation (solar flux) and prevailing wind and precipitation deliver, and an examination of external factors (i.e., climate, use) and internal factors (i.e., brine use in refrigeration). Western faces (260˚N) were found to exhibit the greatest recession at 7-10mm since 1871, while the eastern faces (185˚N) exhibited similar weathering at 7-10mm, however, it was speculated that this recession was a function of algal, lichen, and cyanobacteria overgrowth. Research of this nature divulged the importance of using architectural stone for estimating stone weathering factors and rates and assist us in improving future conservation practices of architectural limestone structures

Teaching With Computers: A Cautionary Finding In An Accounting Class

The study assesses the effects of a hypertext learning aid and GPA on performance in advanced financial accounting. Results indicate that the type of learning aid and GPA significantly affect performance. High GPA students performed better than did the low GPA students. In the study, two versions of the hypertext learning aid were utilized by two different groups of students and compared to a third group of students who had no hypertext learning aid. Use of the full version of the hypertext learning aid results in the lowest performance while students using a modified version of the hypertext learning aid attained the highest exam performance. These differences were found to be statistically significant. Differences in performance between those students who used the modified version and those who used no program were not significant, however. The difference between the full version of the learning aid and the modified version of the learning aid is the degree of information provided to the students; the full version providing the most detailed information. The results suggest that instructors must be careful in the design and use of learning aids