Thermal Quench at Finite t'Hooft Coupling

Using holography we have studied thermal electric field quench for infinite and finite t'Hooft coupling constant. The set-up we consider here is D7-brane embedded in ($\alpha'$ corrected) AdS-black hole background. It is well-known that due to a time-dependent electric field on the probe brane, a time-dependent current will be produced and it will finally relax to its equilibrium value. We have studied the effect of different parameters of the system on equilibration time. As the most important results, we have observed a universal behaviour in the rescaled equilibration time in the very fast quench regime for different values of the temperature and $\alpha'$ correction parameter. It seems that in the slow quench regime the system behaves adiabatically. We have also observed that the equilibration time decreases in finite t'Hooft coupling limit.Comment: 6 pages, 9 figure

Geometric Phase, Bundle Classification, and Group Representation

The line bundles which arise in the holonomy interpretations of the geometric phase display curious similarities to those encountered in the statement of the Borel-Weil-Bott theorem of the representation theory. The remarkable relation of the geometric phase to the classification of complex line bundles provides the necessary tools for establishing the relevance of the Borel-Weil-Bott theorem to Berry's adiabatic phase. This enables one to define a set of topological charges for arbitrary compact connected semisimple dynamical Lie groups. In this paper, the problem of the determination of the parameter space of the Hamiltonian is also addressed. A simple topological argument is presented to indicate the relation between the Riemannian structure on the parameter space and Berry's connection. The results about the fibre bundles and group theory are used to introduce a procedure to reduce the problem of the non-adiabatic (geometric) phase to Berry's adiabatic phase for cranked Hamiltonians. Finally, the possible relevance of the topological charges of the geometric phase to those of the non-abelian monopoles is pointed out.Comment: 30 pages (LaTeX); UT-CR-12-9

Deformed Complex Hermite Polynomials

We study a class of bivariate deformed Hermite polynomials and some of their properties using classical analytic techniques and the Wigner map. We also prove the positivity of certain determinants formed by the deformed polynomials. Along the way we also work out some additional properties of the (undeformed) complex Hermite polynomials and their relationships to the standard Hermite polynomials (of a single real variable).Comment: 12 page

Financial Sector Reform and Its Impact on Investment and Economic Growth: An Econometric Approach

The financial sector is central to economic development as it serves the role of intermediary by mobilising savings and subsequently allocating credit for productive activities. However, in many developing countries including Pakistan, administered interest rate, domestic credit controls, high reserve requirements, use of captive banking system to finance large budgetary requirements of the government and controls on international capital inflows have remained the main features of the monetary policy. These repressive policies had their repercussions in the form of excess liquidity with the banking system, disintermediation of cash flows, segmentation of financial markets, underdeveloped money and capital markets, etc. [McKinnon (1973) and Shaw (1973)], therefore, argued that low interest rate ceilings unduly restrict the real flow of loanable funds, thus depressing the quantity of productive investment. Financial liberalisation, on the other hand, is defined as policy measures designed to deregulate certain operations of the financial system and transform its structure with a view to achieving a liberalised market oriented system with an appropriate regulatory framework. The financial sector reforms would lead to increase in loanable funds by attracting more household savings to bank deposits due to higher interest rates. This, in turn, would result in greater investment and faster economic growth.

Does digital transformation matter for operational risk exposure?

Basel Committee recommends banks maintain a capital buffer for operational risk exposure based on business volumes, assuming aggressive actions for quicker business growth could increase risk exposures. We argue that technological innovations expose banks to more operational risk because technology helps increase business volume, but system failure, problems with internal processes, and disruptions from external and internal security threats are inherent to technology. Based on 10 years of data for 264 banks from 43 countries, we find that digitalized banking operation is an underlying driver of operational risk that comes with increased business volume. Banks proactively take more operational risks by increasing cyber spending to tackle FinTech competition in the digitalized economy. Digitalization could generally matter for operational risk exposure, but the natural experiment does not find cybersecurity threats per se could increase operational risks even though cybersecurity appears to be a serious threat to digital banking. The study creates new avenues for future research

Pan-squamous genomic profiling stratified by anatomic tumor site and viral association

Background: Squamous cell carcinomas (SCC) have diverse anatomic etiologies but may share common genomic biomarkers. We profiled 7,871 unique SCCs across nine anatomic sites to investigate commonality in genomic alterations (GA), tumor mutational burden (TMB), human papillomavirus (HPV) association, and mutational signatures. Methods: Tissue from over 8,100 unique SCC samples originating from nine anatomic sites (anogenital (anus, cervix, penis, vagina, vulva), esophagus, head and neck, lung, and skin) were sequenced by hybrid capture-based comprehensive genomic profiling to evaluate GA and TMB. About 3% of non-cutaneous SCC samples had UV signatures, indicative of potential primary site misdiagnoses, and were filtered from the analysis. Detection of HPV, including high-risk strains 16, 18, 31, 33, and 45, was implemented through de novo assembly of non-human sequencing reads and BLASTn comparison against all viral nucleotide sequences in the NCBI database. Results: The proportion of HPV+ patients by anatomic site varied, with the highest being anal (91%) and cervical (83%). The mutational landscape of each cohort was similar, regardless of anatomic origin, but clustered based on HPV status. The largest differences in GA frequency as stratified by HPV- vs. HPV+ were TP53 (87% vs. 12%), CDKN2A (45% vs. 6%), and PIK3CA (22% vs. 33%). The median TMB in cases originating from HPV-associated sites was similar, regardless of HPV status. Higher median TMB was observed in lung and skin cases, which exhibited significant enrichment of mutational signatures indicative of tobacco- and UV-induced DNA damage, respectively. Conclusions: HPV+ and HPV- SCC populations have distinct genomic profiles and, for the latter, anatomic site is correlated with TMB distribution, secondary to associated carcinogen exposure. As such, biomarkers such as TMB and UV signature can provide unexpected insight into site of origin misdiagnoses and may correlate with benefit from immune checkpoint inhibitors