Measured Behavior of a Deep Excavation in Weathered Rock

An instrumented deep excavation in weathered rock adjacent to a deflection-sensitive historical building is described. Two permanent shoring systems were used, presenting an opportunity to measure and compare their behaviors. Adjacent to the historic structure, a tied-back drilled pier wall was used, while the remainder of the excavation was supported by a tied-back shotcrete wall constructed in top-down fashion. Instrumentation included inclinometers, tiltmeters, and tieback load cells, supplemented by optical surveys. Both support systems performed well, with movements within acceptable ranges. The maximum horizontal deflection of the drilled piers was 0.33 inch (8 mm), one-third to one-fifth that of the shotcrete. Settlements behind the drilled piers were significantly less than behind the shotcrete. Isolated minor cracking and widening of existing cracks occurred in the existing building. Tieback load cell data indicate that the source of movements can extend beyond the theoretical failure wedge

Characterization of microsatellite loci for a threatened species, the King Rail, Rallus elegans, using a next-generation sequencing protocol

The King Rail Rallus elegans (Audubon) has experienced population declines of 4.6 % per year on average since the 1960s. Wetland loss, most severely affecting inland marshes, has significantly reduced this species\u27 distribution to the coastal margins of its historic range. Polymorphic microsatellite markers were generated by 454 pyrosequencing of genomic DNA from King Rails, and Clapper Rails R. longirostris from Louisiana after AFLP enrichment and barcoding of restriction fragment cut sites across individuals. Of 1,419 microsatellite-containing sequences, 20 hypervariable microsatellite loci with up to 20 different alleles were identified at the alignment stage. We characterized nine loci, tested variability in 45 Atlantic coast King Rail samples, and detected 4-19 alleles per locus. Cross-species amplification revealed variability in the Virginia Rail, R. limicola, and Sora, Porzana carolina. These loci will be useful for studying secretive marsh rails, many of which are threatened or endangered. © 2013 Springer Science+Business Media Dordrecht

The Quantum Socket: Three-Dimensional Wiring for Extensible Quantum Computing

Quantum computing architectures are on the verge of scalability, a key requirement for the implementation of a universal quantum computer. The next stage in this quest is the realization of quantum error correction codes, which will mitigate the impact of faulty quantum information on a quantum computer. Architectures with ten or more quantum bits (qubits) have been realized using trapped ions and superconducting circuits. While these implementations are potentially scalable, true scalability will require systems engineering to combine quantum and classical hardware. One technology demanding imminent efforts is the realization of a suitable wiring method for the control and measurement of a large number of qubits. In this work, we introduce an interconnect solution for solid-state qubits: The quantum socket. The quantum socket fully exploits the third dimension to connect classical electronics to qubits with higher density and better performance than two-dimensional methods based on wire bonding. The quantum socket is based on spring-mounted micro wires the three-dimensional wires that push directly on a micro-fabricated chip, making electrical contact. A small wire cross section (~1 mmm), nearly non-magnetic components, and functionality at low temperatures make the quantum socket ideal to operate solid-state qubits. The wires have a coaxial geometry and operate over a frequency range from DC to 8 GHz, with a contact resistance of ~150 mohm, an impedance mismatch of ~10 ohm, and minimal crosstalk. As a proof of principle, we fabricated and used a quantum socket to measure superconducting resonators at a temperature of ~10 mK.Comment: Main: 31 pages, 19 figs., 8 tables, 8 apps.; suppl.: 4 pages, 5 figs. (HiRes figs. and movies on request). Submitte

Height-related risk factors for prostate cancer

Previous studies have reported that adult height is positively associated with the risk of prostate cancer. The authors carried out a population-based case–control study involving 317 prostate cancer cases and 480 controls to further investigate the possibility that height is more strongly associated with advanced, compared with localized forms of this disease. Since the inherited endocrine factors, which in part determine height attained during the growing years, may influence the risk of familial prostate cancer later in life, the relationship with height was also investigated for familial versus sporadic prostate cancers. Adult height was not related to the risk of localized prostate cancer, but there was a moderate positive association between increasing height and the risk of advanced cancer (relative risk (RR) = 1.62; 95% confidence interval (CI) 0.97–2.73, upper versus lowest quartile, P -trend = 0.07). Height was more strongly associated with the risk of prostate cancer in men with a positive family history compared with those reporting a negative family history. The RR of advanced prostate cancer for men in the upper height quartile with a positive family history was 7.41 (95% CI 1.68–32.67, P -trend = 0.02) compared with a reference group comprised of men in the shortest height quartile with a negative family history. Serum insulin-like growth factor-1 levels did not correlate with height amongst men with familial or sporadic prostate cancers. These findings provide evidence for the existence of growth-related risk factors for prostate cancer, particularly for advanced and familial forms of this disease. The possible existence of inherited mechanisms affecting both somatic and tumour growth deserves further investigation. © 2000 Cancer Research Campaig

Iterated colorings of graphs

AbstractFor a graph property P, in particular maximal independence, minimal domination and maximal irredundance, we introduce iterated P-colorings of graphs. The six graph parameters arising from either maximizing or minimizing the number of colors used for each property, are related by an inequality chain, and in this paper we initiate the study of these parameters. We relate them to other well-studied parameters like chromatic number, give alternative characterizations, find graph classes where they differ by an arbitrary amount, investigate their monotonicity properties, and look at algorithmic issues

Effect of high temperature heat treatments on the quality factor of a large-grain superconducting radio-frequency niobium cavity

Large-grain Nb has become a viable alternative to fine-grain Nb for the fabrication of superconducting radio-frequency cavities. In this contribution we report the results from a heat treatment study of a large-grain 1.5 GHz single-cell cavity made of "medium purity" Nb. The baseline surface preparation prior to heat treatment consisted of standard buffered chemical polishing. The heat treatment in the range 800 - 1400 C was done in a newly designed vacuum induction furnace. Q0 values of the order of 2x1010 at 2.0 K and peak surface magnetic field (Bp) of 90 mT were achieved reproducibly. A Q0-value of (5+-1)1010 at 2.0 K and Bp = 90 mT was obtained after heat treatment at 1400 C. This is the highest value ever reported at this temperature, frequency and field. Samples heat treated with the cavity at 1400 C were analyzed by secondary ion mass spectrometry, secondary electron microscopy, energy dispersive X-ray, point contact tunneling and X-ray diffraction and revealed a complex surface composition which includes titanium oxide, increased carbon and nitrogen content but reduced hydrogen concentration compared to a non heat-treated sample