NMR analysis of synthetic human serum albumin alpha-helix 28 identifies structural distortion upon amadori modification

The non-enzymatic reaction between reducing sugars and long-lived proteins in vivo results in the formation of glycation and advanced glycation end products, which alter the properties of proteins including charge, helicity, and their tendency to aggregate. Such protein modifications are linked with various pathologies associated with the general aging process such as Alzheimer disease and the long-term complications of diabetes. Although it has been suggested that glycation and advanced glycation end products altered protein structure and helicity, little structural data and information currently exist on whether or not glycation does indeed influence or change local protein secondary structure. We have addressed this problem using a model helical peptide system containing a di-lysine motif derived from human serum albumin. We have shown that, in the presence of 50 mM glucose and at 37 degrees C, one of the lysine residues in the di-lysine motif within this peptide is preferentially glycated. Using NMR analysis, we have confirmed that the synthetic peptide constituting this helix does indeed form a alpha-helix in solution in the presence of 30% trifluoroethanol. Glycation of the model peptide resulted in the distortion of the alpha-helix, forcing the region of the helix around the site of glycation to adopt a 3(10) helical structure. This is the first reported evidence that glycation can influence or change local protein secondary structure. The implications and biological significance of such structural changes on protein function are discussed

Small Codes for Magic State Distillation

Magic state distillation is a critical component in leading proposals for fault-tolerant quantum computation. Relatively little is known, however, about how to construct a magic state distillation routine or, more specifically, which stabilizer codes are suitable for the task. While transversality of a non-Clifford gate within a code often leads to efficient distillation routines, it appears to not be a necessary condition. Here we have examined a number of small stabilizer codes and highlight a handful of which displaying interesting, albeit inefficient, distillation behaviour. Many of these distill noisy states right up to the boundary of the known undististillable region, while some distill toward non-stabilizer states that have not previously been considered.Comment: Some additional comments and clarifications. Close to published version. Contribution to the Topical Issue "Quantum Information Processing and Communication". 6 pages, 6 figure

New York state's merchandise export gap

New York's merchandise export performance has trailed the nation's for several years. The cause of this gap is not easy to identify: the state maintains a relatively healthy mix of customer markets, remains well represented in industries with strong foreign demand, and continues to enjoy declining labor costs. A broader look at New York's competitiveness, however, reveals that high nonlabor costs may be hurting the state's manufacturing sector and thus its volume of exports.Exports ; Manufactures ; New York (State)

Rules Rather Than Discretion: Lessons from Hurricane Katrina

This paper explores options for programs to be put in place prior to a disaster to avoid large and often poorly-managed expenditures following a catastrophe and to provide appropriate protection against the risk of those large losses which do occur. The lack of interest in insurance protection and mitigation by property owners and by public sector agencies prior to a disaster often creates major problems following a catastrophic event for victims and the government. Property owners who suffer severe damage may not have the financial resources easily at hand to rebuild their property and hence will demand relief. The government is then likely to respond with costly but poorly targeted disaster assistance. To avoid these large and often uneven ex post expenditures, we consider the option of mandatory comprehensive private disaster insurance with risk based rates. It may be more efficient to have an ex ante public program to ensure coverage of catastrophic losses and to subsidize low income residents who cannot afford coverage rather than the current largely ex post public disaster relief program.

Order 3 Symmetry in the Clifford Hierarchy

We investigate the action of the first three levels of the Clifford hierarchy on sets of mutually unbiased bases comprising the Ivanovic MUB and the Alltop MUBs. Vectors in the Alltop MUBs exhibit additional symmetries when the dimension is a prime number equal to 1 modulo 3 and thus the set of all Alltop vectors splits into three Clifford orbits. These vectors form configurations with so-called Zauner subspaces, eigenspaces of order 3 elements of the Clifford group highly relevant to the SIC problem. We identify Alltop vectors as the magic states that appear in the context of fault-tolerant universal quantum computing, wherein the appearance of distinct Clifford orbits implies a surprising inequivalence between some magic states.Comment: 20 pages, 2 figures. Published versio

Lower bounds on the non-Clifford resources for quantum computations

We establish lower-bounds on the number of resource states, also known as magic states, needed to perform various quantum computing tasks, treating stabilizer operations as free. Our bounds apply to adaptive computations using measurements and an arbitrary number of stabilizer ancillas. We consider (1) resource state conversion, (2) single-qubit unitary synthesis, and (3) computational tasks. To prove our resource conversion bounds we introduce two new monotones, the stabilizer nullity and the dyadic monotone, and make use of the already-known stabilizer extent. We consider conversions that borrow resource states, known as catalyst states, and return them at the end of the algorithm. We show that catalysis is necessary for many conversions and introduce new catalytic conversions, some of which are close to optimal. By finding a canonical form for post-selected stabilizer computations, we show that approximating a single-qubit unitary to within diamond-norm precision $\varepsilon$ requires at least $1/7\cdot\log_2(1/\varepsilon) - 4/3$ $T$-states on average. This is the first lower bound that applies to synthesis protocols using fall-back, mixing techniques, and where the number of ancillas used can depend on $\varepsilon$. Up to multiplicative factors, we optimally lower bound the number of $T$ or $CCZ$ states needed to implement the ubiquitous modular adder and multiply-controlled-$Z$ operations. When the probability of Pauli measurement outcomes is 1/2, some of our bounds become tight to within a small additive constant.Comment: 62 page