Large N lattice QCD and its extended strong-weak connection to the hypersphere

We calculate an effective Polyakov line action of QCD at large Nc and large Nf from a combined lattice strong coupling and hopping expansion working to second order in both, where the order is defined by the number of windings in the Polyakov line. We compare with the action, truncated at the same order, of continuum QCD on S^1 x S^d at weak coupling from one loop perturbation theory, and find that a large Nc correspondence of equations of motion found in \cite{Hollowood:2012nr} at leading order, can be extended to the next order. Throughout the paper, we review the background necessary for computing higher order corrections to the lattice effective action, in order to make higher order comparisons more straightforward.Comment: 33 pages, 7 figure

Ruthenium/Iridium Ratios in the Cretaceous-tertiary Boundary Clay: Implications for Global Dispersal and Fractionation Within the Ejecta Cloud

Ruthenium (Ru) and iridium (Ir) are the least mobile platinum group elements (PGE's) within the Cretaceous-Tertiary (K-T) boundary clay (BC). The Ru/Ir ratio is, therefore, the most useful PGE interelement ratio for distinguishing terrestrial and extraterrestrial contributions to the BC. The Ru/Ir ratio of marine K-T sections (1.77 +/- 0.53) is statistically different from that of the continental sections (0.93 +/- 0.28). The marine Ru/Ir ratios are chondritic (C1 = 1.48 +/- 0.09), but the continental ratios are not. We discovered an inverse correlation of shocked quartz size (or distance from the impact site) and Ru/Ir ratio. This correlation may arise from the difference in Ru and Ir vaporization temperature and/or fractionation during condensation from the ejecta cloud. Postsedimentary alteration, remobilization, or terrestrial PGE input may be responsible for the Ru/Ir ratio variations within the groups of marine and continental sites studied. The marine ratios could also be attained if approximately 15 percent of the boundary metals were contributed by Deccan Trap emissions. However, volcanic emissions could not have been the principal source of the PGE's in the BC because mantle PGE ratios and abundances are inconsistent with those measured in the clay. The Ru/Ir values for pristine Tertiary mantle xenoliths (2.6 +/- 0.48), picrites (4.1 +/- 1.8), and Deccan Trap basalt (3.42 +/- 1.96) are all statistically distinct from those measured in the K-T BC

Moduli spaces of G2 manifolds

This paper is a review of current developments in the study of moduli spaces of G2 manifolds. G2 manifolds are 7-dimensional manifolds with the exceptional holonomy group G2. Although they are odd-dimensional, in many ways they can be considered as an analogue of Calabi-Yau manifolds in 7 dimensions. They play an important role in physics as natural candidates for supersymmetric vacuum solutions of M-theory compactifications. Despite the physical motivation, many of the results are of purely mathematical interest. Here we cover the basics of G2 manifolds, local deformation theory of G2 structures and the local geometry of the moduli spaces of G2 structures.Comment: 31 pages, 2 figure

Calculating the chiral condensate diagrammatically at strong coupling

We calculate the chiral condensate of QCD at infinite coupling as a function of the number of fundamental fermion flavours using a lattice diagrammatic approach inspired by recent work of Tomboulis, and other work from the 80's. We outline the approach where the diagrams are formed by combining a truncated number of sub-diagram types in all possible ways. Our results show evidence of convergence and agreement with simulation results at small Nf. However, contrary to recent simulation results, we do not observe a transition at a critical value of Nf. We further present preliminary results for the chiral condensate of QCD with symmetric or adjoint representation fermions at infinite coupling as a function of Nf for Nc = 3. In general, there are sources of error in this approach associated with miscounting of overlapping diagrams, and over-counting of diagrams due to symmetries. These are further elaborated upon in a longer paper.Comment: presented at the 32nd International Symposium on Lattice Field Theory (Lattice 2014), 23-28 June 2014, New York, NY, US

Analysis of wind tunnel test results for a 9.39-per cent scale model of a VSTOL fighter/attack aircraft. Volume 1: Study overview

The ability of current methodologies to accurately predict the aerodynamic characteristics identified as uncertainties was evaluated for two aircraft configurations. The two wind tunnel models studied horizontal altitude takeoff and landing V/STOL fighter aircraft derivatives

Analysis of wind tunnel test results for a 9.39-per cent scale model of a VSTOL fighter/attack aircraft. Volume 3: Effects of configuration variations from baseline

The aerodynamic characteristics of the components of the baseline E205 configuration is presented. Geometric variations from the baseline E205 configuration are also given including a matrix of conrad longitudinal locations and strake shapes

Moving to a Virtual Literacy Practicum: Challenges and Solutions

When the university took the unprecedented move to virtual teaching at the start of the COVID-19 pandemic in March 2020, my challenge, as a teacher educator, was to plan a virtual literacy practicum for master candidates. All aspects of curriculum design were considered, from establishing relationships with schools, parents, and students, considering technology platforms, appropriate technology applications, to considering everyone’s emotional state. In this article, I share the many challenging aspects and the solutions that lead to successful experiences for all participants

Determinants of Timely uptake of ITN and SP (IPT) and Pregnancy time Protected against Malaria in Bukoba, Tanzania.

Insecticides treated nets (ITNs) and intermittent preventive therapy with two doses of sulfadoxine-pyrimethamine (SP IPTp) are the cornerstone for malaria control in pregnancy. Despite the coverage of these interventions being high, it is not known whether they confer optimal protection time against malaria in pregnancy. This study investigated the timing and determinants of timely uptake of SP(IPTp) and ITNs and the pregnancy time protected. A health facility based cross-sectional study was carried out in Bukoba urban district from 16th April to 29 May 2013. Involving pregnant women and post natal mothers attending Reproductive and Child Health (RCH) clinics. Data on their socio-economic background, pregnancy history and attendance to RCH, receipt of a voucher and acquisition of an ITN as well as SP for IPTp were collected. Their responses were validated from the records of antenatal cards. Data was analysed using SPSS computer program version 20. A total of 530 mothers were recruited. The overall uptake of SP IPTp was 96 % and the uptake of two SP (IPTp) doses was 86 %. Timely uptake of 1st dose was predicted by early antenatal booking, [AOR 2.59; 95 % CI 1.51-4.46; P = 0.001], and the availability of SP at the facility [AOR 4.63; 95 % CI 2.51-8.54; P < 0.0001]. Uptake of 2nd dose was independent of any predictor factors. A total of 486 (91.6 %) women received ITNs discount vouchers at different gestational age and of these, less than a quarter (21.4 %) received timely. Timely receipt of discount voucher was highly predicted by early antenatal booking [AOR 200; 95 % CI 80.38-498; P < 0.0001]. Although there is a high coverage of SP IPTp and discount vouchers for ITNs, timely uptake and therefore optimal protection time depended on early antenatal booking, the availability of (SP IPTp) and discount voucher at the health facility