Molecular gas freeze-out in the pre-stellar core L1689B

C17O (J=2-1) observations have been carried out towards the pre-stellar core L1689B. By comparing the relative strengths of the hyperfine components of this line, the emission is shown to be optically thin. This allows accurate CO column densities to be determined and, for reference, this calculation is described in detail. The hydrogen column densities that these measurements imply are substantially smaller than those calculated from SCUBA dust emission data. Furthermore, the C17O column densities are approximately constant across L1689B whereas the SCUBA column densities are peaked towards the centre. The most likely explanation is that CO is depleted from the central regions of L1689B. Simple models of pre-stellar cores with an inner depleted region are compared with the results. This enables the magnitude of the CO depletion to be quantified and also allows the spatial extent of the freeze-out to be firmly established. We estimate that within about 5000 AU of the centre of L1689B, over 90% of the CO has frozen onto grains. This level of depletion can only be achieved after a duration that is at least comparable to the free-fall timescale.Comment: MNRAS letters. 5 pages, 5 figure

Comparison of on-line and off-line methods to quantify reactive oxygen species (ROS) in atmospheric aerosols

Atmospheric aerosol particle concentrations have been linked with a wide range of pulmonary and cardio-vascular diseases but the particle properties responsible for these negative health effects are largely unknown. It is often speculated that reactive oxygen species (ROS) present in atmospheric particles lead to oxidative stress in, and ultimately disease of, the human lung. The quantification of ROS is highly challenging because some ROS components such as radicals are highly reactive and therefore short-lived. Thus, fast analysis methods are likely advantageous over methods with a long delay between aerosol sampling and ROS analysis. We present for the first time a detailed comparison of conventional off-line and fast on-line methods to quantify ROS in organic aerosols. For this comparison a new and fast on-line instrument was built and characterized to quantify ROS in aerosol particles with high sensitivity and a limit of detection of 4 nmol H2O2 equivalents per m3 air. ROS concentrations are measured with a time resolution of approximately 15 min, which allows the tracking of fast changing atmospheric conditions. The comparison of the off-line and on-line method shows that, in oxidized organic model aerosol particles, the majority of ROS have a very short lifetime of a few minutes whereas a small fraction is stable for a day or longer. This indicates that off-line techniques, where there is often a delay of hours to days between particle collection and ROS analysis, may severely underestimate true ROS concentrations and that fast on-line techniques are necessary for a reliable ROS quantification in atmospheric aerosol particles and a meaningful correlation with health outcomes.This work was supported by the Natural Environment Research Council (NE/H52449X/1), the Velux Stiftung (Project 593) and an ERC starting grant (grant no. 279405).This is the accepted manuscript version. The final published version is available from Elsevier at http://www.sciencedirect.com/science/article/pii/S1352231014002787

A Corona Australis cloud filament seen in NIR scattered light II: Comparison with sub-millimeter data

We study a northern part of the Corona Australis molecular cloud that consists of a filament and a dense sub-millimetre core inside the filament. Our aim is to measure dust temperature and sub-mm emissivity within the region. We also look for confirmation that near-infrared (NIR) surface brightness can be used to study the structure of even very dense clouds. We extend our previous NIR mapping south of the filament. The dust colour temperatures are estimated using Spitzer 160um and APEX/Laboca 870um maps. The column densities derived based on the reddening of background stars, NIR surface brightness, and thermal sub-mm dust emission are compared. A three dimensional toy model of the filament is used to study the effect of anisotropic illumination on near-infrared surface brightness and the reliability of dust temperature determination. Relative to visual extinction, the estimated emissivity at 870um is kappa(870) = (1.3 +- 0.4) x 10^{-5} 1/mag. This is similar to the values found in diffuse medium. A significant increase in the sub-millimetre emissivity seems to be excluded. In spite of saturation, NIR surface brightness was able to accurately pinpoint, and better than measurements of the colour excesses of background stars, the exact location of the column density maximum. Both near- and far-infrared data show that the intensity of the radiation field is higher south of the filament.Comment: 9 pages, 9 figures, accepted to A&

A comparison of acyltransferase activities in vitro with the distribution of fatty acids in lecithins and triglycerides in vivo

The location and configuration of a double bond in a fatty acid influences the rate of its acyltransferase‐catalyzed esterification to form lecithin and its distribution in vivo between the primary and secondary positions of triglycerides and lecithins.Saturated acids of shorter chain length are transferred at rates similar to the long chain unsaturated acids.The positional distributions of acids in the diglyceride units of liver triglycerides appear to be similar to that found in the lecithins.Acyltransferase activities measured in vitro have a considerable predictive value in terms of the ultimate distribution of fatty acids in glycerolipids in vivo.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141483/1/lipd0224.pd

StreamJIT: A Commensal Compiler for High-Performance Stream Programming

There are many domain libraries, but despite the performance benefits of compilation, domain-specific languages are comparatively rare due to the high cost of implementing an optimizing compiler. We propose commensal compilation, a new strategy for compiling embedded domain-specific languages by reusing the massive investment in modern language virtual machine platforms. Commensal compilers use the host language's front-end, use host platform APIs that enable back-end optimizations by the host platform JIT, and use an autotuner for optimization selection. The cost of implementing a commensal compiler is only the cost of implementing the domain-specific optimizations. We demonstrate the concept by implementing a commensal compiler for the stream programming language StreamJIT atop the Java platform. Our compiler achieves performance 2.8 times better than the StreamIt native code (via GCC) compiler with considerably less implementation effort.United States. Dept. of Energy. Office of Science (X-Stack Award DE-SC0008923)Intel Corporation (Science and Technology Center for Big Data)SMART3 Graduate Fellowshi

Signal and noise characteristics of patterned media

©2002 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.Analytical expressions of the replay spectra from single- and multiple-recorded bits in patterned media have been derived. The expressions were extended to include position jitter noise and bit-size variations

LoanSTAR Energy Auditing: Update and Changes

Annual savings identified by detailed LoanSTAR audits during the period January, 1989 -December, 1991 are $13.7 million with an investment cost of$46.1 million. These savings represent retrofit projects in state-owned buildings, local government-owned facilities, and independent school districts, accounting for 80%, 16%, and 4% of the investment cost, respectively. A summary of retrofit projects by type is presented and modifications to chillers and chilled water systems account for 26% of the savings and 32% of the cost, followed by lighting retrofits which account for 24% of the savings and 24% of the cost. The Governor's Energy Office has implemented changes to simplify the audit process by eliminating some calculations. Independent calculations and maintenance and operating procedures calculations are no longer required, and some retrofit projects may depend on standard paybacks to identify cost savings

Oestrogen receptor positive breast cancer metastasis to bone: inhibition by targeting the bone microenvironment in vivo

Clinical trials have shown that adjuvant Zoledronic acid (ZOL) reduces the development of bone metastases irrespective of ER status. However, post-menopausal patients show anti-tumour benefit with ZOL whereas pre-menopausal patients do not. Here we have developed in vivo models of spontaneous ER+ve breast cancer metastasis to bone and investigated the effects of ZOL and oestrogen on tumour cell dissemination and growth. ER+ve (MCF7, T47D) or ER−ve (MDA-MB-231) cells were administered by inter-mammary or inter-cardiac injection into female nude mice ± estradiol. Mice were administered saline or 100 μg/kg ZOL weekly. Tumour growth, dissemination of tumour cells in blood, bone and bone turnover were monitored by luciferase imaging, histology, flow cytometry, two-photon microscopy, micro-CT and TRAP/P1NP ELISA. Estradiol induced metastasis of ER+ve cells to bone in 80–100 % of animals whereas bone metastases from ER−ve cells were unaffected. Administration of ZOL had no effect on tumour growth in the fat pad but significantly inhibited dissemination of ER+ve tumour cells to bone and frequency of bone metastasis. Estradiol and ZOL increased bone volume via different mechanisms: Estradiol increased activity of bone forming osteoblasts whereas administration of ZOL to estradiol supplemented mice decreased osteoclast activity and returned osteoblast activity to levels comparable to that of saline treated mice. ER−ve cells require increased osteoclast activity to grow in bone whereas ER+ve cells do not. Zol does not affect ER+ve tumour growth in soft tissue, however, inhibition of bone turnover by ZOL reduced dissemination and growth of ER+ve breast cancer cells in bone

Foliar Fungicides in Seed Corn Production

Since 1982, we have conducted a program to determine the fungicides that may be effective for controlling foliar diseases in inbred and hybrid com. For the past seven years we have limited our research to only inbreds or sister line hybrids. In 1990, we started a cooperative program with seed companies and have conducted our research in commercial seed production fields in five greatly different years in terms of weather patterns. Thirty experiments have been established in seed production fields and 25 fields have been harvested for yield. Five experiments were abandoned because of herbicide injury interactions (2,4-D) with the fungicides, excessive Stewarts disease (a bacterial disease that can not be controlled with fungicides and was devastating), or drought