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Commercially impactful quantum algorithms such as quantum chemistry and Shor's algorithm require a number of qubits and gates far beyond the capacity of any existing quantum processor. Distributed architectures, which scale horizontally by networking modules, provide a route to commercial utility and will eventually surpass the capability of any single quantum computing module. Such processors consume remote entanglement distributed between modules to realize distributed quantum logic. Networked quantum computers will therefore require the capability to rapidly distribute high fidelity entanglement between modules. Here we present preliminary demonstrations of some key distributed quantum computing protocols on silicon T centres in isotopically-enriched silicon. We demonstrate the distribution of entanglement between modules and consume it to apply a teleported gate sequence, establishing a proof-of-concept for T centres as a distributed quantum computing and networking platform.

Quantifying the extent to which existing reserves meet conservation objectives and identifying gaps in coverage are vital to developing systematic protected-area networks. Despite widespread recognition of the Philippines as a global priority for marine conservation, limited work has been undertaken to evaluate the conservation effectiveness of existing marine protected areas (MPAs). Targets for MPA coverage in the Philippines have been specified in the 1998 Fisheries Code legislation, which calls for 15% of coastal municipal waters (within 15 km of the coastline) to be protected within no-take MPAs, and the Philippine Marine Sanctuary Strategy (2004), which aims to protect 10% of coral reef area in no-take MPAs by 2020. We used a newly compiled database of nearly 1000 MPAs to measure progress toward these targets. We evaluated conservation effectiveness of MPAs in two ways. First, we determined the degree to which marine bioregions and conservation priority areas are represented within existing MPAs. Second, we assessed the size and spacing patterns of reserves in terms of best-practice recommendations. We found that the current extent and distribution of MPAs does not adequately represent biodiversity. At present just 0.5% of municipal waters and 2.7-3.4% of coral reef area in the Philippines are protected in no-take MPAs. Moreover, 85% of no-take area is in just two sites; 90% of MPAs are <1 km². Nevertheless, distances between existing MPAs should ensure larval connectivity between them, providing opportunities to develop regional-scale MPA networks. Despite the considerable success of community-based approaches to MPA implementation in the Philippines, this strategy will not be sufficient to meet conservation targets, even under a best-case scenario for future MPA establishment. We recommend that implementation of community-based MPAs be supplemented by designation of additional large no-take areas specifically located to address conservation targets.

The Shake-and-Bake method of structure determination is a new direct methods phasing algorithm based on a minimum-variance, phase invariant residual, which is referred to as the minimal principle. Previously, the algorithm had been applied only to known structures. This algorithm has now been applied to two previously unknown structures that contain 105 and 110 non-hydrogen atoms, respectively. This report focuses on (i) algorithmic and parametric optimizations of Shake-and-Bake and (ii) the determination of two previously unknown structures. Traditional tangent formula phasing techniques were unable to unravel these two new structures.

The crystal structure of triclinic lysozyme, comprised of 1,001 non-H protein atoms and ≈ 200 bound water molecules, has been determined ab initio (using native data alone) by the ``Shake-and-Bake'' method by using the computer program SnB. This is the largest structure determined so far by the SnB program. Initial experiments, using default SnB parameters derived from studies of smaller molecules, were unsuccessful. In fact, such experiments produced electron density maps dominated by a single large peak. This problem was overcome by considering the choice of protocol used during the parameter-shift phase refinement. When each phase was subjected to a single shift of ± 157.5 degrees during each SnB cycle, an unusually high percentage of random trials (≈ 22%) yielded correct solutions within 750 cycles. This success rate is higher than that typically observed, even for much smaller structures.