Spotlight on deep carbon research.

Professor Marie Edmonds is a volcanologist at the University of Cambridge. She is interested in the role of magmatic volatiles in magma genesis, volcanic eruptions, and volatile geochemical cycling. Dr. Robert Hazen is a geologist at Carnegie Science and executive director of the Deep Carbon Observatory. His latest research has focused on the co-evolution of the geospheres and biospheres, and mineral diversity and distribution. Marie and Robert apply their research to help understand the chemical and biological roles of carbon in Earth

Really useful qualifications and learning? Exploring the policy effects of new sub-bachelors degree qualifications

The symposium paper addresses the conference theme of the relationship between policy, practice and research by critically examining policy discourse in lifelong learning and the role of research in understanding policy effects. Empirical and theoretical research on the rationale and practice of examples of short cycle HE including sub-bachelors degree level qualifications, such as Higher National Certificates and Diplomas and Foundation Degrees are the focus

Cylindrical gravitational waves in expanding universes: Models for waves from compact sources

New boundary conditions are imposed on the familiar cylindrical gravitational wave vacuum spacetimes. The new spacetime family represents cylindrical waves in a flat expanding (Kasner) universe. Space sections are flat and nonconical where the waves have not reached and wave amplitudes fall off more rapidly than they do in Einstein-Rosen solutions, permitting a more regular null inifinity.Comment: Minor corrections to references. A note added in proo

Fault-tolerant quantum computation with high threshold in two dimensions

We present a scheme of fault-tolerant quantum computation for a local architecture in two spatial dimensions. The error threshold is 0.75% for each source in an error model with preparation, gate, storage and measurement errors.Comment: 4 pages, 4 figures; v2: A single 2D layer of qubits (simple square lattice) with nearest-neighbor translation-invariant Ising interaction suffices. Slightly improved threshol

A study of silver chloride containing gold

Measurements of optical absorption, dielectric loss, photoconductivity and photolysis have been used to investigate the properties of silver chloride containing gold. The gold enters the silver chloride lattice either substitutionaly or as a separate phase of aurous or auric chloride depending on the method of preparation. The most interesting properties are shown by the aurous chloride phase which is produced by annealing in chlorine or nitrogen at 673º K and quenching to room temperature. The temperature and concentration dependences of the optical absorption of the aurous chloride phase indicate that the energy for the formation of a separate phase of aurous chloride approaches a minimum near 673º K. The incorporation of gold sensitises silver chloride for colloid formation. The photolysis of silver chloride is determined by measuring the optical absorption during irradiation. In silver chloride containing substitutional Au or auric chloride as a separate phase, the photolysis occurs mainly on the. surface. The incorporation of a separate phase of aurous chloride results in strong volume sensitivity to both blue and red light. The volume sensitivity is explained in terms of the spectral sensitisation of silver chloride by the aurous chloride. At temperatures above 170ºK irradiation results in the formation of silver and gold colloid and the conversion of aurous chloride to auric chloride. The thermal development which occurs at 423°K is attributed to the thermal decomposition of the aurous chloride phase. The properties of the deep hole and electron traps in silver chloride sensitised with europium have been studied by measuring both the photoconductivity and the thermally stimulated conductivity at low temperatures. The slow growth in the photoconductivity which occurs' on blue irradiation at 130º K is shown to be due to the effects of deep hole trapping and the gradual filling of intrinsic electron traps. Dielectric loss measurements are used to determine the binding energy of cation vacancies to impurity ions and the activation energy for reorientation of cation vacancies about impurity ions in silver chloride and bromide containing chromium and in silver chloride containing europium. These measurements and those of photoconductivity and thermally stimulated conductivity are made on a spectrometer developed for the continuous measurement of complex permittivity

Energy-Efficient Multiprocessor Scheduling for Flow Time and Makespan

We consider energy-efficient scheduling on multiprocessors, where the speed of each processor can be individually scaled, and a processor consumes power $s^{\alpha}$ when running at speed $s$, for $\alpha>1$. A scheduling algorithm needs to decide at any time both processor allocations and processor speeds for a set of parallel jobs with time-varying parallelism. The objective is to minimize the sum of the total energy consumption and certain performance metric, which in this paper includes total flow time and makespan. For both objectives, we present instantaneous parallelism clairvoyant (IP-clairvoyant) algorithms that are aware of the instantaneous parallelism of the jobs at any time but not their future characteristics, such as remaining parallelism and work. For total flow time plus energy, we present an $O(1)$-competitive algorithm, which significantly improves upon the best known non-clairvoyant algorithm and is the first constant competitive result on multiprocessor speed scaling for parallel jobs. In the case of makespan plus energy, which is considered for the first time in the literature, we present an $O(\ln^{1-1/\alpha}P)$-competitive algorithm, where $P$ is the total number of processors. We show that this algorithm is asymptotically optimal by providing a matching lower bound. In addition, we also study non-clairvoyant scheduling for total flow time plus energy, and present an algorithm that achieves $O(\ln P)$-competitive for jobs with arbitrary release time and $O(\ln^{1/\alpha}P)$-competitive for jobs with identical release time. Finally, we prove an $\Omega(\ln^{1/\alpha}P)$ lower bound on the competitive ratio of any non-clairvoyant algorithm, matching the upper bound of our algorithm for jobs with identical release time

Comparison of Low Cost Miniature Spectrometers for Volcanic SO2 Emission Measurements

Miniature ultraviolet USB coupled spectrometers have become ubiquitously applied over the last decade for making volcanic SO2 emission rate measurements. The dominantly applied unit has recently been discontinued however, raising the question of which currently available devices should now be implemented. In this paper, we consider, and make recommendations on this matter, by studying a number of inexpensive compact spectrometers in respect of measurement performance and thermal behaviour. Of the studied units, the Avaspec demonstrated the best prospects for the highest time resolution applications, but in the majority of cases, we anticipate users likely preferring the less bulky USB2000+s

Semiclassical Analysis of the Wigner 9J9J-Symbol with Small and Large Angular Momenta

We derive a new asymptotic formula for the Wigner $9j$-symbol, in the limit of one small and eight large angular momenta, using a novel gauge-invariant factorization for the asymptotic solution of a set of coupled wave equations. Our factorization eliminates the geometric phases completely, using gauge-invariant non-canonical coordinates, parallel transports of spinors, and quantum rotation matrices. Our derivation generalizes to higher $3nj$-symbols. We display without proof some new asymptotic formulas for the $12j$-symbol and the $15j$-symbol in the appendices. This work contributes a new asymptotic formula of the Wigner $9j$-symbol to the quantum theory of angular momentum, and serves as an example of a new general method for deriving asymptotic formulas for $3nj$-symbols.Comment: 18 pages, 16 figures. To appear in Phys. Rev.

The utility of renal ultrasonography in the diagnosis of renal colic in emergency department patients

Objective: Computed tomography (CT) is an imaging modality used to detect renal stones. However, there is concern about the lifetime cumulative radiation exposure attributed to CT. Ultrasonography (US) has been used to diagnose urolithiasis, thereby avoiding radiation exposure. The objective of this study was to determine the ability of US to identify renal colic patients with a low risk of requiring urologic intervention within 90 days of their initial emergency department (ED) visit. Methods: We completed a retrospective medical record review for all adult patients who underwent ED-ordered renal US for suspected urolithiasis over a 1-year period. Independent, double data extraction was performed for all imaging reports and US results were categorized as normal, suggestive of ureterolithiasis, ureteric stone seen or disease unrelated to urolithiasis. Charts were reviewed to determine how many patients underwent subsequent CT and urologic intervention. Results: Of the 817 renal US procedures ordered for suspected urolithiasis during the study period, the results of 352 (43.2%) were classified as normal, and only 2 (0.6%) of these patients required urologie intervention. The results of 177 (21.7%) renal US procedures were suggestive of ureterolithiasis. Of these, 12 (6.8%) patients required urologie intervention. Of the 241 (29.5%) patients who had a ureteric stone seen on US, 15 (6.2%) required urologie intervention. The rate of urologie intervention was significantly lower in those with normal results on US (p \u3c 0.001) than in those with abnormal results on US. Conclusion: A normal result on renal US predicts a low likelihood for urologie intervention within 90 days for adult ED patients with suspected urolithiasis