AdS/CFT correspondence and D1/D5 systems in theories with 16 supercharges

We discuss spectra of $AdS_3$ supergravities, arising in the near horizon geometry of D1/D5 systems in orbifolds/orientifolds of type IIB theory with 16 supercharges. These include models studied in a recent paper (hep-th/0012118), where the group action involves also a shift along a transversal circle, as well as IIB/$\Omega I_4$, which is dual to IIB on $K3$. After appropriate assignements of the orbifold group eigenvalues and degrees to the supergravity single particle spectrum, we compute the supergravity elliptic genus and find agreement, in the expected regime of validity, with the elliptic genus obtained using U-duality map from (4,4) CFTs of U-dual backgrounds. Since this U-duality involves the exchange of KK momentum $P$ and D1 charge $N$, it allows us to test the (4,4) CFTs in the $P < N/4$ and $N < P/4$ regimes by two different supergravity duals.Comment: 28 pages, no figure

Radial Vibration of an Aeolotropic Cylindrical Shell of Varying Density in a Magnetic Field

In this paper, we have discussed the problem of vibration of cylindrical shell of aelotropic material of variable density for two different cases- first, when the density varies linearly and second, when it varies inversely as the radius vecto

Supersymmetries in Free Fermionic Strings

Consistent heterotic free fermionic string models are classified in terms of their number of spacetime supersymmetries, N. For each of the six distinct choices of gravitino sector, we determine what number of supersymmetries can survive additional GSO projections. We prove by exhaustive search that only three of the six can yield N = 1, in addition to the N = 4, 2, or 0 that five of the six can yield. One choice of gravitino sector can only produce N = 4 or 0. Relatedly, we find that only Z_2, Z_4, and Z_8 twists of the internal fermions with worldsheet supersymmetry are consistent with N=1 in free fermionic models. Any other twists obviate N=1.Comment: changes to match journal version; tex, 53 page

Left ventricular lead misplacement discovered a decade after cardiac resynchronization therapy-defibrillator implantation: a case report.

Introduction: Satisfactory left ventricular (LV) lead placement into the coronary sinus (CS) can be achieved in the majority of patients but there are still instances of acute failure most often due to anatomical differences, for example due to tortuous CS anatomy. Chronic LV lead misplacement and its delayed discovery is not a common scenario. It is unclear if chronic dual right ventricular pacing can hasten the progression of heart failure. Case presentation: A 73-year-old lady presented to our cardiac centre with severe heart failure. She had non-ischaemic dilated cardiomyopathy with underlying left bundle branch block and a cardiac resynchronization therapy-defibrillator device in situ for the past decade. She also had a chronic pericardial effusion of unknown aetiology. Whilst the patient was being treated for acute heart failure, it was noted on patient telemetry that the QRS morphology for supposed bi-ventricular pacing was unusual. This led to a lateral chest radiograph and a CS venogram to be performed, both of which confirmed that the LV lead was in fact not in the CS. Plans were made to place a new LV lead but unfortunately the patient continued to clinically deteriorate despite maximal treatment and died before this could be performed. Discussion: It is only with thorough review of the electrocardiographic data and chest radiography that led to the discovery of chronic LV lead misplacement. This case illustrates the importance of expert review of radiographic imaging and electrocardiographic data in patients with implanted cardiac devices

Differential Gene Expression Profiling in Bed Bug (Cimex Lectularius L.) Fed on Ibuprofen and Caffeine in Reconstituted Human Blood

The recent resurgence of the common bed bug (Cimex lectularius L.) infestations worldwide has created a need for renewed research on biology, behavior, population genetics and management practices. Humans serve as exclusive hosts to bed bugs in urban environments. Since a majority of humans consume Ibuprofen (as pain medication) and caffeine (in coffee and other soft drinks) so bug bugs subsequently acquire Ibuprofen and caffeine through blood feeding. However, the effect of these chemicals at genetic level in bed bug is unknown. Therefore, this research was conducted to determine differential gene expression in bed bugs using RNA-Seq analysis at dosages of 200 ppm Ibuprofen and 40 ppm caffeine incorporated into reconstituted human blood and compared against the control. Total RNA was extracted from a single bed bug per replication per treatment and sequenced. Read counts obtained were analyzed using Bioconductor software programs to identify differentially expressed genes, which were then searched against the non-redundant (nr) protein database of National Center for Biotechnology Information (NCBI). Data on comparison of differentially expressed genes between control and Ibuprofen treatments revealed that 659 genes were significantly differentially regulated and 95% of them returned BLAST hits. Heat stress proteins were among the top significantly differentially down regulated genes. Comparison of the control vs caffeine treatments revealed that 2,161 genes were significantly differently regulated (Pad

Kaluza-Klein States versus Winding States: Can Both Be Above the String Scale?

When closed strings propagate in extra compactified dimensions, a rich spectrum of Kaluza-Klein states and winding states emerges. Since the masses of Kaluza-Klein states and winding states play a reciprocal role, it is often believed that either the lightest Kaluza-Klein states or the lightest winding states must be at or below the string scale. In this paper, we demonstrate that this conclusion is no longer true for compactifications with non-trivial shape moduli. Specifically, we demonstrate that toroidal compactifications exist for which all Kaluza-Klein states as well as all winding states are heavier than the string scale. This observation could have important phenomenological implications for theories with reduced string scales, suggesting that it is possible to cross the string scale without detecting any states associated with spacetime compactification.Comment: 8 pages, LaTeX, no figure

Correlation between prevalence rates of pulmonary tuberculosis, tuberculous infection and non-specific sensitivity

Data from the initial examination of a BCG trial have been analysed to determine mathematical relationship, if any, between the prevalence of infection and disease. Also, because non-specific sensitivity otters protection against the development of tuberculosis and because there was high prevalence of nonspecific sensitivity in the area of the study, relationship between nonspecific sensitivity and tuberculosis had also been studied. Results of the analysis showed that relationship between prevalence of tuberculous infection and disease is not amenable to any simple mathematical quantification. However, the values of the coefficients of correlation between the two were statistically highly significant suggesting that the prevalence of one varied directly with the prevalence of the other in the community, and that preve-lence of infection may be used as an indicator for the prevalence of disease at different points of time. The analysis also showed the existence of an inverse relationship between prevalence of tuber-culosis ane prevalence of non-specific sensitivity tending to confirm the previous finding that the latter offered protection against the other

Symmetries and conservation laws of higher-order PDEs

PhD., Faculty of Science, University of the Witwatersrand, 2011The construction of conserved vectors using Noether’s theorem via a knowledge of a Lagrangian (or via the recently developed concept of partial Lagrangians) is well known. The formulae to determine these for higher-order flows is somewhat cumbersome and becomes more so as the order increases. We carry out these for a class of fourth, fifth and sixth order PDEs. In the latter case, we involve the fifth-order KdV equation using the concept of ‘weak’ Lagrangians better known for the third-order KdV case. We then consider the case of a mixed ‘high-order’ equations working on the Shallow Water Wave and Regularized Long Wave equations. These mixed type equations have not been dealt with thus far using this technique. The construction of conserved vectors using Noether’s theorem via a knowledge of a Lagrangian is well known. In some of the examples, our focus is that the resultant conserved flows display some previously unknown interesting ‘divergence properties’ owing to the presence of the mixed derivatives. We then analyse the conserved flows of some multi-variable equations that arise in Relativity. In addition to a larger class of conservation laws than those given by the isometries or Killing vectors, we may conclude what the isometries are and that these form a Lie subalgebra of the Noether symmetry algebra. We perform our analysis on versions of the Vaidya metric yielding some previously unknown information regarding the corresponding manifold. Lastly, with particular reference to this metric, we also show the variations that occur for the unknown functions. We discuss symmetries of classes of wave equations that arise as a consequence of the Vaidya metric. The objective of this study is to show how the respective geometry is responsible for giving rise to a nonlinear inhomogeneous wave equation as an alternative to assuming the existence of nonlinearities in the wave equation due to physical considerations. We find Lie and Noether point symmetries of the corresponding wave equations and give some reductions. Some interesting physical 4 conclusions relating to conservation laws such as energy, linear and angular momenta are also determined. We also present some interesting comparisons with the standard wave equations (on a ‘flat geometry’). Finally, we pursue the nature of the flow of a third grade fluid with regard to its underlying conservation laws. In particular, the fluid occupying the space over a wall is considered. At the surface of the wall, suction or blowing velocity is applied. By introducing a velocity field, the governing equations are reduced to a class of PDEs. A complete class of conservation laws for the resulting equations are constructed and analysed using the invariance properties of the corresponding multipliers/characteristics

Heterotic strings on T3/ℤ2, Nikulin involutions and M-theory

We first describe the low energy dynamics of ten dimensional heterotic supergravity compactified on the smooth, flat 3-manifold ${\mathbb T^3}/{\mathbb Z_2}$, without supersymmetry, and explain how it arises from flat heterotic gauge fields. The semi-classical theory has both Coulomb and Higgs branches of non-supersymmetric vacua. We then give an exact worldsheet description as asymmetric orbifolds of $\mathbb T^3$, where the orbifold generator involves a Nikulin non-symplectic involution $\theta$ of the even self-dual lattice $\Gamma_{(19,3)}$. Along the way we briefly compare our findings with M-theory on $\text{K3}/\theta$. Our construction gives a novel CFT description of the semi-classical field theory moduli space. In particular, the Wilson line parameters in the lattice $I\subset \Gamma_{(19,3)}$ of signature $(19-s,1)$ which is invariant under $\theta$, and in its orthogonal complement $N$, correspond respectively to Coulomb and Higgs branch moduli. There is a rich pattern of transitions amongst Higgs and Coulomb branches which we describe using the worldsheet theory

Efficacy of Transport Mikron Against Nuisance Ants When Applied Around Structures, 2015

Ants are nuisance pests around the homes and other structures. Insecticide baits and sprays are commonly used for controlling ants. The research was conducted to determine efficacy of Transport Mikron and Temprid SC against these nuisance ants. The trial was conducted around two buildings on East Campus, University of Nebraska-Lincoln, Lincoln, NE. A total of 20 experimental plots were established with 3 ft buffer zone between individual plots. The dimension of each experimental plot consists of 20 ft lengthx10 ft width + 3 ft high on foundation wall (260 ft2). Each treatment was replicated four times yielding 1040 ft2. Four plots were randomly assigned to one of the five treatments. The experimental design was a completely randomized design (CRD). Pretreatment ant population was monitored by placing four ant baittube traps made of cylindrical plastic tube (17x100mm (VWR, Chicago, IL)) in each experimental unit on 20 Aug. Peanut butter (0.5 inch diam) on paper was used as a bait in each. Foraging nuisance ant populations were pooled across species, counted, and used as a baseline for calculating the percent reduction in ant populations resulting from treatments. All insecticide treatments were applied using a 1-gallon B&G Compressed Air Sprayer (Jackson, GA) on 25 Aug. Ants were monitored at 1, 7, 14, and 31 days after insecticide treatment (DAT) using the same techniques used for pretreatment assessment. The percent reduction trends were evaluated using pre- and post-treatment nuisance ant population counts. Data were analyzed as repeated measures ANOVA (P\u3c0.05) using PROC GLIMMIX (SAS 9.4. SAS institute, NC). Means were analyzed/sorted by time with significant differences being collection interval specific